Rice grain size and chalkiness are important traits that influence grain yield and quality,respectively.Mining of genes for grain yield and appearance quality and clarification of their action modes are of great impor...Rice grain size and chalkiness are important traits that influence grain yield and quality,respectively.Mining of genes for grain yield and appearance quality and clarification of their action modes are of great importance in rice breeding.In this study,a rice protein disulfide isomerase-like enzyme PDIL2-3 was characterized.Expression analysis revealed that PDIL2-3 was highly expressed in endosperm and spikelet hulls.The PDIL2-3-cri lines generated by CRISPR/Cas9 technology exhibited a chalky grain phenotype with altered storage substance accumulation and increased grain size and weight,whereas exactly opposite results were obtained for PDIL2-3 overexpression lines.Cytological experiments revealed that PDIL2-3-cri increased rice seed length mainly by increasing the cell number and rice seed width mainly by increasing the cell size in grains,implying that PDIL2-3 regulates the grain size by influencing both cell division and expansion of spikelet hulls.Further flow cytometric analysis validated that PDIL2-3 has a negative effect on cell proliferation,preventing DNA duplication and cell division in spikelet hulls.Moreover,q RT-PCR results showed that the expression levels of genes related to cell cycle and storage substance synthesis were significantly changed in PDIL2-3-cri transgenic lines.Thus,our results indicated that PDIL2-3 plays a pivotal role in influencing grain size and quality of rice by affecting cell division/expansion and storage substance accumulation,providing new insights into the function of PDIL family members in rice and enriching the genetic resources for rice breeding.展开更多
Appearance and cooked rice elongation are key quality traits of rice. Although some QTL for these traits have been identified, understanding of the genetic relationship between them remains limited. In the present stu...Appearance and cooked rice elongation are key quality traits of rice. Although some QTL for these traits have been identified, understanding of the genetic relationship between them remains limited. In the present study, large phenotypic variation was observed in 760 accessions from the 3 K Rice Genomes Project for both appearance quality and cooked rice elongation. Most component traits of appearance quality and cooked rice elongation showed significant pairwise correlations, but a low correlation was found between appearance quality and cooked rice elongation. A genome-wide association study identified 74 QTL distributed on all 12 chromosomes for grain length, grain width, length to width ratio, degree of endosperm with chalkiness, rice elongation difference, and elongation index. Thirteen regions containing QTL stably expressed in multiple environments and/or exerting pleiotropic effects on multiple traits were detected. By gene-based association analysis and haplotype analysis, 46 candidate genes, including five cloned genes, and 49 favorable alleles were identified for these 13 QTL. The effect of the candidate gene Wx on rice elongation difference was validated by a transgenic strategy. These results shed light on the genetic bases of appearance quality and cooked rice elongation and provide gene resources for improving rice quality by molecular breeding.展开更多
A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines(A)and 5 restorer lines(R)along with their F1(A×R)and F2 populations.The unconditional and conditional analyses of...A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines(A)and 5 restorer lines(R)along with their F1(A×R)and F2 populations.The unconditional and conditional analyses of genetic models and the corresponding statistic methods,including endospermic,cytoplasmic,and maternal plant genetic systems,were used to analyze the genetic relationships between protein content(PC)and the appearance quality traits of indica rice(Oryza sativa L.).The results from unconditional analysis indicated that PC was significantly correlated with the appearance quality traits of rice,except for the brown rice thickness(BRT).Only the genetic covariance between PC and the brown rice width(BRW)was positively correlative,whereas all the other pairwise traits were negatively correlative.The results from conditional analysis revealed that the weight of brown rice(WBR)or the amylose content(AC)could significantly affect the relationships between PC and the appearance quality traits of indica rice.The conditional analysis showed that WBR might negatively affect the relationships between PC and the brown rice length(BRL),BRW,or BRT through the geuotype x environmental(GE)interaction effects,but positively affected the relationships between PC and the ratio of brown rice length to width(RLW)or the ratio of brown rice length to thickness(RLT).The amylase content could positively affect the relationships between PC and BRL,RLW,RLT through the cytoplasmic effects and maternal additive effects,but negatively affected the relationships between PC and BRW.展开更多
This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype ×...This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length （CGL） and cooked grain shape （CGSH）. General combining ability （GCA） and specific combining ability （SCA） effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index （GEI）. In the controlling of the inheritance of milled grain shape （GSH）, milled grain width （MGW）, GEI, milled grain length （MGL）, CGSH and cooked grain width （CGW）, the additive gene effects were more important than non-additive one. The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 （GSH） to 0.36 （CGL）. GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.展开更多
To elucidate the relationship between ethylene evolution from the grains and the appearance quality of rice, ten different rice genotypes were used to determine the ethylene evolution rate, 1-aminocylopropane-1-carbox...To elucidate the relationship between ethylene evolution from the grains and the appearance quality of rice, ten different rice genotypes were used to determine the ethylene evolution rate, 1-aminocylopropane-1-carboxylic acid （ACC） concentration in grains during grain filling and the appearance quality of rice, and the effects of chemical regulators on concentrations of ethylene and ACC in the grains during grain filling were also investigated to verify the roles of ethylene in the rice quality formation. The ethylene evolution rates and ACC concentrations in grains during the mid and late grain filling stages were very significantly and positively correlated with chalky kernel percentage and chalkiness. The cultivars with a low ACC concentration in grains exhibited a close amyloplast arrangement and small space between starch granules, whereas those with a high ACC concentration in grains showed a loose arrangement and wide space between the granules. Application of 1 μmol/L ACC to panicles at mid and late grain filling stages significantly loosened amyloplast arrangement and increased chalky kernel percentage, chalky area and chalkiness, and the results were reversed when 1 μmol/L amino-ethoxyvinylglycine, an inhibitor of ACC synthesis enzyme, was applied to panicles. A practice of moderate dry-wet alternate irrigation reduced ethylene evolution and ACC concentration in grains and thereby reduced chalkiness. The results suggested that ethylene and ACC in grains play an important role in the endosperm structure and appearance quality of rice, and the appearance quality would be improved by reducing ethylene evolution and ACC in grains through either variety breeding and selection, or chemical regulations or cultivation techniques.展开更多
To clarify the optimal water management in large-scale fields under high temperatures at the ripening period,effective water managements during this period for improvement of yield,appearance quality and palatability ...To clarify the optimal water management in large-scale fields under high temperatures at the ripening period,effective water managements during this period for improvement of yield,appearance quality and palatability were investigated.Compared with intermittent irrigation and flooded irrigation,the soil temperature with saturated irrigation remained low throughout the day,and the decrease rate of the bleeding rate of hills was the lowest.These results suggested that the saturated irrigation maintained root activity.For the three irrigation types,the number of spikelets per m2 and 1000-grain weight were similar,however,saturated irrigation resulted in significantly higher rice yield due to improvement in the percentage of ripened grains.The saturated irrigation produced a high percentage of perfect rice grains and thicker brown rice grain,furthermore,the palatability of cooked rice was excellent because protein content and hardness/adhesion ratio were both low.Thus,under high-temperature ripening conditions,soil temperature was lowered and root activity was maintained when applying saturated irrigation after heading time.The results indicated that saturated irrigation is an effective countermeasure against high-temperature ripening damage.展开更多
supported by a grant from the National High-Tech R＆D Program of China （2014AA10A603, 2014AA10A604）;a grant from the Youth Foundation in Sichuan, China （2011JTD0022）;the special fund for China Agricultural Researc...supported by a grant from the National High-Tech R＆D Program of China （2014AA10A603, 2014AA10A604）;a grant from the Youth Foundation in Sichuan, China （2011JTD0022）;the special fund for China Agricultural Research System （CARS-01-08）;the Provincial Specialized Funds for Innovation Ability Promotion in Sichuan, China （2013GXJS005）展开更多
Development of hybrid rice with high yield and grain quality is a goal of rice breeding.To investigate the genetic mechanism of heterosis for rice milling and appearance quality in indica/xian rice,QTL mapping was con...Development of hybrid rice with high yield and grain quality is a goal of rice breeding.To investigate the genetic mechanism of heterosis for rice milling and appearance quality in indica/xian rice,QTL mapping was conducted using 1061 recombinant inbred lines(RILs)derived from a cross of the xian rice cultivars Quan 9311B(Q9311B)and Wu-shan-si-miao(WSSM),and a backcross F_(1)(BC_(1)F_(1)) population developed by crossing the RILs with Quan 9311A(Q9311A),combined with phenotyping in two environments.The F_(1) hybrid(Q9311A×WSSM)showed various degrees of heterosis for milling and appearance quality.A total of 142 main-effect QTL(M-QTL)and 407 pairs of epistatic QTL(E-QTL)were identified for five milling and appearance quality traits and grain yield per plant(GYP)in the RIL,BC_(1)F_(1) and mid-parental heterosis(H_(MP)) populations.Differential detection of QTL in three populations revealed that most additive loci detected in the RILs did not show heterotic effects,but some of them did contribute to BC_(1)F_(1) trait performance.Unlike heterosis of GYP,single-locus overdominance and epistasis were the main contributors to heterosis for milling and appearance quality.Epistasis contributed more to the heterosis for milling quality than to that for appearance quality.Three(four)QTL regions harboring opposite(consistent)directions of favorable allele effects for GYP and grain quality were identified,indicating the presence of partial genetic overlaps between GYP and grain quality.Three strategies are proposed to develop hybrid rice with high yield and good grain quality:1)pyramiding favorable alleles with consistent directions of gene effects for GYP and grain quality at the M-QTL on different chromosomes;2)introgressing favorable alleles for GYP and grain quality into the parents and then pyramiding and fixing these additive effects in hybrids;and 3)pyramiding overdominant and dominant loci and minimizing or eliminating underdominant loci from the parents.展开更多
This study aimed to clarify the appearance quality,sensory quality,and their relationship of different flue-cured tobacco varieties in Chenzhou,Hunan.A total of 183 samples of C3F-grade tobacco leaves were collected f...This study aimed to clarify the appearance quality,sensory quality,and their relationship of different flue-cured tobacco varieties in Chenzhou,Hunan.A total of 183 samples of C3F-grade tobacco leaves were collected from Chenzhou from 2021 to 2023,and the relationship between the appearance quality and sensory quality was analyzed by the correlation analysis.The results showed that‘Yunyan 87’and‘K326’showcased the typical burnt-sweetness and bouquet-sweetness aroma in Nanling area,while‘Yunyan 301’,‘Xiangyan 5’,and‘Xiangyan 7’presented a bouquet-sweetness aroma.Maturity had a significantly negative correlation with the typical burnt-sweetness and bouquet-sweetness aroma.A suitable level of maturity was beneficial for highlighting the burnt-sweetness aroma of flue-cured tobacco in Chenzhou.The oil content,softness,and color difference between leaf front and back had significantly positive correlations with the aroma quality of tobacco.Maturity and leaf structure had significantly negative correlations with off-odours and irritating odour.In conclusion,‘Yunyan 87’and‘K326’in Chenzhou could manifest the burntsweetness and bouquet-sweetness aroma,and suitable maturity was conducive to the release of the burnt-sweetness aroma.展开更多
Applying iodine fertilizers to cultivate iodine-rich crops for daily intake is an effective approach for iodine supplementation,especially for aromatic rice.Field experiments were conducted during the early growing se...Applying iodine fertilizers to cultivate iodine-rich crops for daily intake is an effective approach for iodine supplementation,especially for aromatic rice.Field experiments were conducted during the early growing seasons of 2021 and 2022 to evaluate the impacts of foliar application of iodine fertilizer on aromatic rice and to explore the optimal iodine fertilizer concentration.At the full heading stage,six different concentrations of sodium iodide solutions of 0%(CK),0.010%(T1),0.025%(T2),0.050%(T3),0.075%(T4),and 0.100%(T5)were applied to indica aromatic rice cultivars Meixiangzhan 2 and Xiangyaxiangzhan.The results showed that sodium iodide treatments significantly increased the iodine and sodium contents in both leaves and grains.Compared with the CK,the T1 and T2 treatments increased the 2-acetyl-1-pyrroline(2-AP)content in mature grains by 8.41%-101.66%and 13.58%-74.60%,respectively.Improvements in the contents of 1-pyrroline-5-carboxylic acid,proline,1-pyrroline,and methylglyoxal,as well as the activity of proline dehydrogenase were also detected.Additionally,sodium iodide treatments remarkably decreased the chalky grain rate,chalkiness area,and chalkiness degree of aromatic rice,with the T2 treatment exhibiting a 17.79%-47.42%decrease in chalkiness degree compared with the CK.Meanwhile,T1 and T2 treatments showed beneficial impacts on chlorophyll content,photosynthetic characteristics,and yield components,while T3,T4,and T5 treatments exhibited adverse effects on leaf and grain yields.The linear discriminant analysis revealed significant differences between treatments.The correlation analysis and piecewise structural equation modeling showed that the iodine and sodium influenced the photosynthetic characteristics and chlorophyll content of the leaves,thereby regulating the 2-AP biosynthesis and yield components,ultimately affecting the 2-AP content and yield.Overall,this study suggests that foliar application of 0.025%sodium iodide is an effective method to enrich the iodine content in rice grains,improve the grain aroma and appearance quality of aromatic rice,without detrimental effects on grain yield.展开更多
Rice grain size is a primary characteristic essential for artificial domestication and breeding,governed by grain length,width,and thickness.In this study,we cloned Grain Size 10(GS10),a novel gene via mapbased clonin...Rice grain size is a primary characteristic essential for artificial domestication and breeding,governed by grain length,width,and thickness.In this study,we cloned Grain Size 10(GS10),a novel gene via mapbased cloning.Biochemical,molecular,and genetic studies were performed to elucidate the GS10 involved grain size mechanism in rice.Mutant of GS10 lead to reduced grain size due to alterations in cell expansion.Additionally,GS10 is responsible for the formation of notched-belly grains,especially in smaller grain varieties possessing loss-function mutations.Overexpression of GS10 in Nipponbare results in increasing grain length,grain weight and improve the appearance quality of rice.GS10 encodes conserved protein with uncharacterized function.Furthermore,GS10 regulates the grain size by interacting OsBRICK1,a subunit of the WAVE complex that governs actin nucleation and affects the assembly of microfilaments in rice.Together,our study demonstrates that,GS10 positively regulates the grain length and grain weight,which is beneficial for further improvements in yield characteristics.展开更多
This study aimed to optimize the application rates and base-topdressing ratios of nitrogen and potassium for flue-cured tobacco in Chaling,Zhuzhou,Hunan.The tobacco variety‘Yunyan 87’was planted and subjected to eig...This study aimed to optimize the application rates and base-topdressing ratios of nitrogen and potassium for flue-cured tobacco in Chaling,Zhuzhou,Hunan.The tobacco variety‘Yunyan 87’was planted and subjected to eight different treatments with different application rates and base-topdressing ratios of nitrogen and potassium.The effect of different treatments on the agronomic traits,dry matter accumulation,yield,and quality of tobacco were compared.The results showed that the growth period of each treatment became shortened as the application rates of nitrogen and potassium decreased and as the base-topdressing ratios of nitrogen and potassium increased.The dry matter accumulation decreased with the reduction in the application rates of nitrogen and potassium.The yield and output value of T1 were the highest,reaching 2097.39 kg/hm^(2)and 65018.90 yuan/hm^(2),respectively,both significantly increasing by 57.5%compared with those of the control(CK).In addition,the proportions of leaves of high and mid-high grade in T1 were also the highest,reaching 73.31%and 88.79%,respectively,both higher than those of CK.The appearance evaluation results showed that the appearance quality scores of tobacco leaves of grades B2F and C3F in T1 were the highest,reaching 51 points,both of which were 3 points higher than that those of CK.All the treatments were consistent in terms of color,maturity,leaf structure,body,oil,and color intensity.Therefore,it was suggested that the tobacco production in Chaling should appropriately increase the proportions of nitrogen and potassium as base fertilizers on the basis of conventional fertilization,which was conducive to improving the yield and appearance quality of flue-cured tobacco.展开更多
This study was designed to elucidate the relationship between root chemical signals and the quality of rice. Various rice genotypes were used. Zeatin （Z） ＋ zeatin riboside （ZR）, abscisic acid （ABA）, 1-aminocylo...This study was designed to elucidate the relationship between root chemical signals and the quality of rice. Various rice genotypes were used. Zeatin （Z） ＋ zeatin riboside （ZR）, abscisic acid （ABA）, 1-aminocylopropane -1-carboxylic acid （ACC）, and organic acids in roots during grain filling and the appearance quality, cooking/eating quality were investigated. The correlations among them were analyzed. The results showed that Z ＋ ZR concentrations in the roots at mid- and lategrain-filling stages were significantly and positively correlated with the gel consistency and alkali spreading value （r = 0.72^＊ - 0.90^＊＊）, whereas negatively correlated with the amylose content （r = -0.68^＊ - -0.78^＊＊）. ABA concentrations in roots at mid- grain-filling stage were significantly and negatively correlated with the gel consistency and alkali spreading value （r = -0.90^＊＊-0.91^＊＊）, and positively correlated with the amylose content （r = 0.87^＊＊）. ACC concentrations in root exudates at mid-grain-filling stage were very significantly correlated with the percentage of chalky grains and chalkiness （r = 0.97^＊＊ - 0.98^＊＊）, and those at late-grain-filling stage Were significantly correlated with chalkiness and chalky size （r = 0.69^＊ - 0.96^＊＊）. The more the malic acid and succinic acid exuded from roots for a cultivar, the greater the breakdown values and the smaller the setback values in the starch profile, and the results were reversed for a cultivar with more tartaric acid and citric acid exuded from roots during the grain-filling period. The cultivar with more lactic acid in exudates had smaller gel consistency and alkali spreading values, but had greater amylose content. When roots were treated with exogenous ZR, ABA, and ACC during grain filling, effects of the chemicals on the rice quality were consistent with the relationships of the endogenous hormones （Z ＋ ZR, ABA, and ACC） with the quality indexes. Using rape cake as organic fertilizer can increase the concentrations of malic acid and succinic acids exuded from roots as well as the breakdown value in starch profile and reduce the setback value. The results suggest that root chemical signals play important roles in the formation of rice quality, and dee quality could be improved through regulating the signals.展开更多
The interplanting with zero-tillage of rice, i.e. direct sowing rice 10-20 days before wheat harvesting, and remaining about 30-cm high stubble after cutting wheat or rice with no tillage, is a new cultivation technol...The interplanting with zero-tillage of rice, i.e. direct sowing rice 10-20 days before wheat harvesting, and remaining about 30-cm high stubble after cutting wheat or rice with no tillage, is a new cultivation technology in wheat-rice rotation system. To study the effects of interplanting with zero tillage and straw manure on rice growth and quality, an experiment was conducted in a wheat-rotation rotation system. Four treatments, i.e. ZIS （Zero-tillage, straw manure and rice interplanting）, Zt （Zero-tillage, no straw manure and rice interplanting）, PTS （Plowing tillage, straw manure and rice transplanting）, and PT （Plowing tillage, no straw manure and rice transplanting）, were used. ZtS reduced plant height, leaf area per plant and the biomass of rice plants, but the biomass accumulation of rice at the late stage was quicker than that under conventional transplanting cultivation. In the first year （2002）, there was no significant difference in rice yield among the four treatments. However, rice yield decreased in interplanting with zero-tillage in the second year （2003）. Compared with the transplanting treatments, the number of filled grains per panicle decreased but l000-grain weight increased in interplanting with zero-tillage, which were the main factors resulting in higher yield, tnterplanting with zero-tillage improved the milling and appearance qualities of rice. The rates of milled and head rice increased while chalky rice rate and chalkiness decreased in interplanting with zero-tillage. Zero-tillage and interplanting also affected rice nutritional and cooking qualities. In 2002, ZIS showed raised protein content, decreased amylose content, softer gel consistency, resulting in improved rice quality. In 2003, zero-tillage and interplanting decreased protein content and showed similar amylose content as compared with transplanting treatments. Moreover, protein content in PTS was obviously increased in comparison with the other three treatments. The rice in interplanting with zero-tillage treatments had higher peak viscosity and breakdown, lower setback, showing better rice taste quality. The straw manure had no significant effect on rice viscosity under interplanting with zero-tillage, but had the negative influence on the rice taste quality under transplanting with plowing tillage.展开更多
High temperature(HT)accompanied with strong light(SL)often occurs in early indica rice production during grout filling stage in Southern China,which accelerates grain ripening.Two indica rice cultivars with different ...High temperature(HT)accompanied with strong light(SL)often occurs in early indica rice production during grout filling stage in Southern China,which accelerates grain ripening.Two indica rice cultivars with different amylose content(Zhongjiazao17,ZJZ17,high amylose content;Xiangzaoxian45,XZX45,low amylose content)were grown under control(CK),HT,and HT+SL conditions during grout filling to determine the effects on grain yield and quality of rice.The results showed that compared with CK,HT and HT+SL significantly reduced the 1000-grain weight and filled grain rate whether in high or low amylose content early indica rice cultivars during grout filling,resulting in a significantly lower grain yield.Meanwhile,HT and HT+SL significantly decreased the milled rice rate,brown rice rate and head rice rate,whereas significantly increased chalky rate and chalky degree;and breakdown decreased and setback,pasting temperature increased in the cultivars,leading to the poor processing,appearance and cooking and eating quality of early indica rice cultivars.Compared with HT,the yield of ZJZ17 was significantly decreased under HT+SL,due to the lower 1000-grain weight.However,the effect of HT+SL on rice quality varied in the cultivars.In general,the yield and rice quality of ZJZ17 were relatively poor under HT+SL.Our results suggested that HT and HT+SL during grout filling had significant damage to the yield and quality of early indica rice cultivars,especially HT+SL,while the high amylose cultivar ZJZ17 showed a higher negative effect under HT+SL.展开更多
[Objective] The aim was to explore tobacco varieties which satisfy tobacco formula and is suitable to be grown in ecotopes simultaneously. [Method] Interior and exterior qualities of tobacco were compared and identifi...[Objective] The aim was to explore tobacco varieties which satisfy tobacco formula and is suitable to be grown in ecotopes simultaneously. [Method] Interior and exterior qualities of tobacco were compared and identified based on agronomic and economic characters of tobacco in fields. [Result] Yunshai No.1 was better in both agronomic and economic characters. Specifically, the fragrance was dominated by empyreumatique and aroma; the highly-qualified variety is fragrant and sweet, with little irritation, which gives the tobacco smoke a light, mild flavor. As for Virgini- a934, economic characters were better, but agronomic characters were just ordinary. Similar to Yunshai No.l, dominated by empyreumatique and aroma, the variety was with distinctive resin and herbaceous fragrance. What＇s more, it tasted good with high quality and usability. Cunsanpi was ordinary in agronomic characters, and poor in economic characters, with coordinated quality and chemical composition. It is fra- grant and the smoke is clean. However, the quality was not so high and it tasted not so good. Tengruan No.2 was good in agronomic characters, but poor in eco- nomic characters, which gives delicate fragrance, but not clean enough. Waiweiba and Mijie Qinggeng neither taste well nor smell sweet, performing ordinary in agro- nomic and economic characters. Hence, the two varieties seem bad in quality and ranks poorly. [Conclusion] In terms of sensory quality, the varieties from high to low were Yunshai No.1, Virginia 934, Cunsanpi, Tengruan No.2, Waiweiba and Mijie Qinggeng.展开更多
To select elite germplasms, 112 mutants derived from japonica rice cultivar Wuyujing 3 were evaluated. The yield components such as panicle number per square meter, grain number per panicle, and grain weight were meas...To select elite germplasms, 112 mutants derived from japonica rice cultivar Wuyujing 3 were evaluated. The yield components such as panicle number per square meter, grain number per panicle, and grain weight were measured. The quality traits such as percentage of chalky grains（PCG）, brown rice yield（BRY）, milled rice yield（MRY）, degree of milling（DM）, amylose content（AC）, protein content（PC）, and relationships among traits were inverstigated. Results showed that grain yield ranged from 2.15 to 12.49 t/hm2 with a mean of 6.4 t/hm2 and number of grains per square meter contributed for 94.64% in grain yield variation. For quality traits, all rice mutants had short size（grain length ≤ 5.5 mm） and bold shape（grain length to width ratio = 1.10-2.00）. Most of rice mutants（87.5%） had PCG values below 20%. All mutants had MRY values above 50%, AC values below 20%, and PC values below 10%. Percentage of chalky grains was significantly negatively correlated with MRY and positively correlated with DM. BRY and MRY were significantly negatively correlated with DM. PC was significantly and positively correlated with MRY and negatively correlated with DM, while AC had no significant correlation with these quality traits. It was concluded that there were 25 rice mutants which fulfilled the major requirements of Jiangsu standard japonica rice such as low percentage of chalky grains, low amylose content, optimal protein content, and which could be used as elite germplasms. Thus the mutants identified may lead to significant progress in improvement of rice quality.展开更多
[Objective] The aim of this study was to evaluate the effects of soil amend- ment composed of biochar and inorganic mineral material on growth and develop- ment, yield and output value of flue-cured tobacco in South A...[Objective] The aim of this study was to evaluate the effects of soil amend- ment composed of biochar and inorganic mineral material on growth and develop- ment, yield and output value of flue-cured tobacco in South Anhui Province. [Method] A field plot experiment was conducted. The agronomic traits, yield and output value, as well as appearance quality and flavor of flue-cured tobacco were evaluated. [Re- suit] The soil amendments composed of biochars and inorganic mineral materials could significantly increase plant height, stem diameter, leaf size, yield and output of flue-cured tobacco, as well as proportion of first-grade tobacco leaves at the middle and late growth period. The yield in the X3 treatment group （70% T20 ＋ 30% ZC） was highest, and it was higher than that in the control group by 398 kg/hm2. Com- pared with that in the control group, the output of flue-cured tobacco in the X3 treatment group was increased by 10 290 yuan/hm2. In terms of appearance quality and flavor, the flue-cured tobacco leaves in the soil amendment treatment groups were all better than those in the control group. [Conclusion] The application of soil amendment composed of biochar and inorganic mineral material is an effective mea- sure to improve tobacco-growing soil, promote tobacco growth and development, im- prove tobacco yield and output and improve tobacco leaf quality in South Anhui re- gion.展开更多
In laser wakefield acceleration,injecting an external electron beam at a certain energy is a promising approach for achieving a high-quality electron beam with low energy spread and low emittance.In this paper,the pro...In laser wakefield acceleration,injecting an external electron beam at a certain energy is a promising approach for achieving a high-quality electron beam with low energy spread and low emittance.In this paper,the process of laser wakefield acceleration with an external injection at 10 pC has been studied in simulations.A Bayesian optimization method is used to optimize the key laser and plasma parameters so that the electron beam is accelerated to the expected energy with a small emittance and energy spread growth.The effect of the rising edge of the plasma on the transverse properties of the electron beam is simulated and optimized in order to ensure that the external electron beam is injected into the plasma without significant emittance growth.Finally,a high-quality electron beam with an energy of 1.5 GeV,a normalized transverse emittance of 0.5 mm·mrad and a relative energy spread of 0.5%at 10 pC is obtained.展开更多
Improving grain quality, which is composed primarily of the appearance of the grain and its cooking and milling attributes, is a major objective of many rice-producing areas in China. In the present study, we conducte...Improving grain quality, which is composed primarily of the appearance of the grain and its cooking and milling attributes, is a major objective of many rice-producing areas in China. In the present study, we conducted a marker-based genetic analysis of the appearance and milling quality of rice （Oryza sativa L.） grains using a doubled-haploid population derived from a cross between the indica inbred Zhenshan 97 strain and the japonica inbred Wuyujing 2 strain. Quantitative trait locus （QTL） analysis using a mixed linear model approach revealed that the traits investigated were affected by one to seven QTLs that individually explained 4.0%-30.7% of the phenotypic variation. Cumulatively, the QTL for each trait explained from 12.9% to 61.4% of the phenotypic variation. Some QTLs tended to have a pleiotropic or location-linked association as a cause of the observed phenotypic correlations between different traits. Improvement of the characteristics of grain appearance and grain weight, as well as an improvement in the milling quality of rice grains, would be expected by a recombination of different QTLs using marker-assisted selection.展开更多
基金supported in part by grants from the National Natural Science Foundation of China(32472141,32101746,and 32102231)Natural Science Foundation of Hubei Province(JCZRLH202500540,2021CFB033,and 2022CFB393)。
文摘Rice grain size and chalkiness are important traits that influence grain yield and quality,respectively.Mining of genes for grain yield and appearance quality and clarification of their action modes are of great importance in rice breeding.In this study,a rice protein disulfide isomerase-like enzyme PDIL2-3 was characterized.Expression analysis revealed that PDIL2-3 was highly expressed in endosperm and spikelet hulls.The PDIL2-3-cri lines generated by CRISPR/Cas9 technology exhibited a chalky grain phenotype with altered storage substance accumulation and increased grain size and weight,whereas exactly opposite results were obtained for PDIL2-3 overexpression lines.Cytological experiments revealed that PDIL2-3-cri increased rice seed length mainly by increasing the cell number and rice seed width mainly by increasing the cell size in grains,implying that PDIL2-3 regulates the grain size by influencing both cell division and expansion of spikelet hulls.Further flow cytometric analysis validated that PDIL2-3 has a negative effect on cell proliferation,preventing DNA duplication and cell division in spikelet hulls.Moreover,q RT-PCR results showed that the expression levels of genes related to cell cycle and storage substance synthesis were significantly changed in PDIL2-3-cri transgenic lines.Thus,our results indicated that PDIL2-3 plays a pivotal role in influencing grain size and quality of rice by affecting cell division/expansion and storage substance accumulation,providing new insights into the function of PDIL family members in rice and enriching the genetic resources for rice breeding.
基金funded by the National Key Research and Development Program of China (2016YFD0100301)Project for Cultivating New Transgenic Varieties (2016ZX08009003-004)+2 种基金the Agricultural Science and Technology Innovation Program and the Cooperation and Innovation Mission (CAAS-ZDXT202001)Open Fund of Hubei Collaborative Innovation Center for Grain Industry (HCICGI2020-06)the National Natural Science Foundation of China (U19A2025 and 31870229)。
文摘Appearance and cooked rice elongation are key quality traits of rice. Although some QTL for these traits have been identified, understanding of the genetic relationship between them remains limited. In the present study, large phenotypic variation was observed in 760 accessions from the 3 K Rice Genomes Project for both appearance quality and cooked rice elongation. Most component traits of appearance quality and cooked rice elongation showed significant pairwise correlations, but a low correlation was found between appearance quality and cooked rice elongation. A genome-wide association study identified 74 QTL distributed on all 12 chromosomes for grain length, grain width, length to width ratio, degree of endosperm with chalkiness, rice elongation difference, and elongation index. Thirteen regions containing QTL stably expressed in multiple environments and/or exerting pleiotropic effects on multiple traits were detected. By gene-based association analysis and haplotype analysis, 46 candidate genes, including five cloned genes, and 49 favorable alleles were identified for these 13 QTL. The effect of the candidate gene Wx on rice elongation difference was validated by a transgenic strategy. These results shed light on the genetic bases of appearance quality and cooked rice elongation and provide gene resources for improving rice quality by molecular breeding.
基金This work was supported by National Natural Science Foundation of China(No.30571198)the Science and Technology Office of Zhejiang Province(No.2004C2020-2 and No.011102471).
文摘A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines(A)and 5 restorer lines(R)along with their F1(A×R)and F2 populations.The unconditional and conditional analyses of genetic models and the corresponding statistic methods,including endospermic,cytoplasmic,and maternal plant genetic systems,were used to analyze the genetic relationships between protein content(PC)and the appearance quality traits of indica rice(Oryza sativa L.).The results from unconditional analysis indicated that PC was significantly correlated with the appearance quality traits of rice,except for the brown rice thickness(BRT).Only the genetic covariance between PC and the brown rice width(BRW)was positively correlative,whereas all the other pairwise traits were negatively correlative.The results from conditional analysis revealed that the weight of brown rice(WBR)or the amylose content(AC)could significantly affect the relationships between PC and the appearance quality traits of indica rice.The conditional analysis showed that WBR might negatively affect the relationships between PC and the brown rice length(BRL),BRW,or BRT through the geuotype x environmental(GE)interaction effects,but positively affected the relationships between PC and the ratio of brown rice length to width(RLW)or the ratio of brown rice length to thickness(RLT).The amylase content could positively affect the relationships between PC and BRL,RLW,RLT through the cytoplasmic effects and maternal additive effects,but negatively affected the relationships between PC and BRW.
基金The projcct was carried out in the farm and laboratory of Rice Research Institute of Iran(RRII)in Rasht
文摘This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length （CGL） and cooked grain shape （CGSH）. General combining ability （GCA） and specific combining ability （SCA） effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index （GEI）. In the controlling of the inheritance of milled grain shape （GSH）, milled grain width （MGW）, GEI, milled grain length （MGL）, CGSH and cooked grain width （CGW）, the additive gene effects were more important than non-additive one. The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 （GSH） to 0.36 （CGL）. GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.
基金This paper was translated from its Chinese version in Chinese Journal of Rice Science.
文摘To elucidate the relationship between ethylene evolution from the grains and the appearance quality of rice, ten different rice genotypes were used to determine the ethylene evolution rate, 1-aminocylopropane-1-carboxylic acid （ACC） concentration in grains during grain filling and the appearance quality of rice, and the effects of chemical regulators on concentrations of ethylene and ACC in the grains during grain filling were also investigated to verify the roles of ethylene in the rice quality formation. The ethylene evolution rates and ACC concentrations in grains during the mid and late grain filling stages were very significantly and positively correlated with chalky kernel percentage and chalkiness. The cultivars with a low ACC concentration in grains exhibited a close amyloplast arrangement and small space between starch granules, whereas those with a high ACC concentration in grains showed a loose arrangement and wide space between the granules. Application of 1 μmol/L ACC to panicles at mid and late grain filling stages significantly loosened amyloplast arrangement and increased chalky kernel percentage, chalky area and chalkiness, and the results were reversed when 1 μmol/L amino-ethoxyvinylglycine, an inhibitor of ACC synthesis enzyme, was applied to panicles. A practice of moderate dry-wet alternate irrigation reduced ethylene evolution and ACC concentration in grains and thereby reduced chalkiness. The results suggested that ethylene and ACC in grains play an important role in the endosperm structure and appearance quality of rice, and the appearance quality would be improved by reducing ethylene evolution and ACC in grains through either variety breeding and selection, or chemical regulations or cultivation techniques.
基金supported by the grants from the Project of the National Agriculture and Food Research Organization Bio-oriented Technology Research Advancement Institution in Japan(the Special Scheme to Create Dynamism in Agriculture,Forestry and Fisheries through Deploying Highly Advanced Technology)(Grant No.shoNavi1000)。
文摘To clarify the optimal water management in large-scale fields under high temperatures at the ripening period,effective water managements during this period for improvement of yield,appearance quality and palatability were investigated.Compared with intermittent irrigation and flooded irrigation,the soil temperature with saturated irrigation remained low throughout the day,and the decrease rate of the bleeding rate of hills was the lowest.These results suggested that the saturated irrigation maintained root activity.For the three irrigation types,the number of spikelets per m2 and 1000-grain weight were similar,however,saturated irrigation resulted in significantly higher rice yield due to improvement in the percentage of ripened grains.The saturated irrigation produced a high percentage of perfect rice grains and thicker brown rice grain,furthermore,the palatability of cooked rice was excellent because protein content and hardness/adhesion ratio were both low.Thus,under high-temperature ripening conditions,soil temperature was lowered and root activity was maintained when applying saturated irrigation after heading time.The results indicated that saturated irrigation is an effective countermeasure against high-temperature ripening damage.
基金supported by a grant from the National High-Tech R&D Program of China (2014AA10A603, 2014AA10A604)a grant from the Youth Foundation in Sichuan, China (2011JTD0022)+1 种基金the special fund for China Agricultural Research System (CARS-01-08)the Provincial Specialized Funds for Innovation Ability Promotion in Sichuan, China (2013GXJS005)
文摘supported by a grant from the National High-Tech R＆D Program of China （2014AA10A603, 2014AA10A604）;a grant from the Youth Foundation in Sichuan, China （2011JTD0022）;the special fund for China Agricultural Research System （CARS-01-08）;the Provincial Specialized Funds for Innovation Ability Promotion in Sichuan, China （2013GXJS005）
基金funded by the Key Research and Development Project of Hainan Province(ZDYF2021XDNY128)the Hainan Yazhou Bay Seed Lab Project(B21HJ0216)+1 种基金the Agricultural Science and Technology Innovation Programthe Cooperation and Innovation Mission(CAAS-ZDXT202001)。
文摘Development of hybrid rice with high yield and grain quality is a goal of rice breeding.To investigate the genetic mechanism of heterosis for rice milling and appearance quality in indica/xian rice,QTL mapping was conducted using 1061 recombinant inbred lines(RILs)derived from a cross of the xian rice cultivars Quan 9311B(Q9311B)and Wu-shan-si-miao(WSSM),and a backcross F_(1)(BC_(1)F_(1)) population developed by crossing the RILs with Quan 9311A(Q9311A),combined with phenotyping in two environments.The F_(1) hybrid(Q9311A×WSSM)showed various degrees of heterosis for milling and appearance quality.A total of 142 main-effect QTL(M-QTL)and 407 pairs of epistatic QTL(E-QTL)were identified for five milling and appearance quality traits and grain yield per plant(GYP)in the RIL,BC_(1)F_(1) and mid-parental heterosis(H_(MP)) populations.Differential detection of QTL in three populations revealed that most additive loci detected in the RILs did not show heterotic effects,but some of them did contribute to BC_(1)F_(1) trait performance.Unlike heterosis of GYP,single-locus overdominance and epistasis were the main contributors to heterosis for milling and appearance quality.Epistasis contributed more to the heterosis for milling quality than to that for appearance quality.Three(four)QTL regions harboring opposite(consistent)directions of favorable allele effects for GYP and grain quality were identified,indicating the presence of partial genetic overlaps between GYP and grain quality.Three strategies are proposed to develop hybrid rice with high yield and good grain quality:1)pyramiding favorable alleles with consistent directions of gene effects for GYP and grain quality at the M-QTL on different chromosomes;2)introgressing favorable alleles for GYP and grain quality into the parents and then pyramiding and fixing these additive effects in hybrids;and 3)pyramiding overdominant and dominant loci and minimizing or eliminating underdominant loci from the parents.
文摘This study aimed to clarify the appearance quality,sensory quality,and their relationship of different flue-cured tobacco varieties in Chenzhou,Hunan.A total of 183 samples of C3F-grade tobacco leaves were collected from Chenzhou from 2021 to 2023,and the relationship between the appearance quality and sensory quality was analyzed by the correlation analysis.The results showed that‘Yunyan 87’and‘K326’showcased the typical burnt-sweetness and bouquet-sweetness aroma in Nanling area,while‘Yunyan 301’,‘Xiangyan 5’,and‘Xiangyan 7’presented a bouquet-sweetness aroma.Maturity had a significantly negative correlation with the typical burnt-sweetness and bouquet-sweetness aroma.A suitable level of maturity was beneficial for highlighting the burnt-sweetness aroma of flue-cured tobacco in Chenzhou.The oil content,softness,and color difference between leaf front and back had significantly positive correlations with the aroma quality of tobacco.Maturity and leaf structure had significantly negative correlations with off-odours and irritating odour.In conclusion,‘Yunyan 87’and‘K326’in Chenzhou could manifest the burntsweetness and bouquet-sweetness aroma,and suitable maturity was conducive to the release of the burnt-sweetness aroma.
基金supported by the National Natural Science Foundation of China(Grant No.31971843)the Technology System of Modern Agricultural Industry in Guangdong Province,China(Grant No.2020KJ105)+1 种基金the Guangzhou Science and Technology Project,Guangdong Province,China(Grant No.202103000075)the Special Rural Revitalization Funds of Guangdong Province,China(Grant No.2021KJ382)。
文摘Applying iodine fertilizers to cultivate iodine-rich crops for daily intake is an effective approach for iodine supplementation,especially for aromatic rice.Field experiments were conducted during the early growing seasons of 2021 and 2022 to evaluate the impacts of foliar application of iodine fertilizer on aromatic rice and to explore the optimal iodine fertilizer concentration.At the full heading stage,six different concentrations of sodium iodide solutions of 0%(CK),0.010%(T1),0.025%(T2),0.050%(T3),0.075%(T4),and 0.100%(T5)were applied to indica aromatic rice cultivars Meixiangzhan 2 and Xiangyaxiangzhan.The results showed that sodium iodide treatments significantly increased the iodine and sodium contents in both leaves and grains.Compared with the CK,the T1 and T2 treatments increased the 2-acetyl-1-pyrroline(2-AP)content in mature grains by 8.41%-101.66%and 13.58%-74.60%,respectively.Improvements in the contents of 1-pyrroline-5-carboxylic acid,proline,1-pyrroline,and methylglyoxal,as well as the activity of proline dehydrogenase were also detected.Additionally,sodium iodide treatments remarkably decreased the chalky grain rate,chalkiness area,and chalkiness degree of aromatic rice,with the T2 treatment exhibiting a 17.79%-47.42%decrease in chalkiness degree compared with the CK.Meanwhile,T1 and T2 treatments showed beneficial impacts on chlorophyll content,photosynthetic characteristics,and yield components,while T3,T4,and T5 treatments exhibited adverse effects on leaf and grain yields.The linear discriminant analysis revealed significant differences between treatments.The correlation analysis and piecewise structural equation modeling showed that the iodine and sodium influenced the photosynthetic characteristics and chlorophyll content of the leaves,thereby regulating the 2-AP biosynthesis and yield components,ultimately affecting the 2-AP content and yield.Overall,this study suggests that foliar application of 0.025%sodium iodide is an effective method to enrich the iodine content in rice grains,improve the grain aroma and appearance quality of aromatic rice,without detrimental effects on grain yield.
基金supported by Projects of International Cooperation NSFC(31961143016,31101203)Guizhou Provincial Science and Technology Projects(QKHJC-ZK[2022]YB537)+4 种基金the Fundamental Research Funds of Central Public Welfare Research Institutions(CPSIBRF-CNRRI-202102,Y2020YJ17)Independent Project of State Key Laboratory of Rice Biology(2020Z2KT10201)High-quality and Resistant Hybrid Rice Germplasm Creation and New Varieties Development with International Competitiveness(2022KJCX45,YBXM2437)Zhejiang Provincial Science and Technology Projects(2022R51009)Inner Mongolia Breeding Joint Research Project(YZ2023004).
文摘Rice grain size is a primary characteristic essential for artificial domestication and breeding,governed by grain length,width,and thickness.In this study,we cloned Grain Size 10(GS10),a novel gene via mapbased cloning.Biochemical,molecular,and genetic studies were performed to elucidate the GS10 involved grain size mechanism in rice.Mutant of GS10 lead to reduced grain size due to alterations in cell expansion.Additionally,GS10 is responsible for the formation of notched-belly grains,especially in smaller grain varieties possessing loss-function mutations.Overexpression of GS10 in Nipponbare results in increasing grain length,grain weight and improve the appearance quality of rice.GS10 encodes conserved protein with uncharacterized function.Furthermore,GS10 regulates the grain size by interacting OsBRICK1,a subunit of the WAVE complex that governs actin nucleation and affects the assembly of microfilaments in rice.Together,our study demonstrates that,GS10 positively regulates the grain length and grain weight,which is beneficial for further improvements in yield characteristics.
文摘This study aimed to optimize the application rates and base-topdressing ratios of nitrogen and potassium for flue-cured tobacco in Chaling,Zhuzhou,Hunan.The tobacco variety‘Yunyan 87’was planted and subjected to eight different treatments with different application rates and base-topdressing ratios of nitrogen and potassium.The effect of different treatments on the agronomic traits,dry matter accumulation,yield,and quality of tobacco were compared.The results showed that the growth period of each treatment became shortened as the application rates of nitrogen and potassium decreased and as the base-topdressing ratios of nitrogen and potassium increased.The dry matter accumulation decreased with the reduction in the application rates of nitrogen and potassium.The yield and output value of T1 were the highest,reaching 2097.39 kg/hm^(2)and 65018.90 yuan/hm^(2),respectively,both significantly increasing by 57.5%compared with those of the control(CK).In addition,the proportions of leaves of high and mid-high grade in T1 were also the highest,reaching 73.31%and 88.79%,respectively,both higher than those of CK.The appearance evaluation results showed that the appearance quality scores of tobacco leaves of grades B2F and C3F in T1 were the highest,reaching 51 points,both of which were 3 points higher than that those of CK.All the treatments were consistent in terms of color,maturity,leaf structure,body,oil,and color intensity.Therefore,it was suggested that the tobacco production in Chaling should appropriately increase the proportions of nitrogen and potassium as base fertilizers on the basis of conventional fertilization,which was conducive to improving the yield and appearance quality of flue-cured tobacco.
基金supported by the National Natural Science Foundation of China(30370828)the Natural Science Foundation of Jiangsu Province,China(BK200341).
文摘This study was designed to elucidate the relationship between root chemical signals and the quality of rice. Various rice genotypes were used. Zeatin （Z） ＋ zeatin riboside （ZR）, abscisic acid （ABA）, 1-aminocylopropane -1-carboxylic acid （ACC）, and organic acids in roots during grain filling and the appearance quality, cooking/eating quality were investigated. The correlations among them were analyzed. The results showed that Z ＋ ZR concentrations in the roots at mid- and lategrain-filling stages were significantly and positively correlated with the gel consistency and alkali spreading value （r = 0.72^＊ - 0.90^＊＊）, whereas negatively correlated with the amylose content （r = -0.68^＊ - -0.78^＊＊）. ABA concentrations in roots at mid- grain-filling stage were significantly and negatively correlated with the gel consistency and alkali spreading value （r = -0.90^＊＊-0.91^＊＊）, and positively correlated with the amylose content （r = 0.87^＊＊）. ACC concentrations in root exudates at mid-grain-filling stage were very significantly correlated with the percentage of chalky grains and chalkiness （r = 0.97^＊＊ - 0.98^＊＊）, and those at late-grain-filling stage Were significantly correlated with chalkiness and chalky size （r = 0.69^＊ - 0.96^＊＊）. The more the malic acid and succinic acid exuded from roots for a cultivar, the greater the breakdown values and the smaller the setback values in the starch profile, and the results were reversed for a cultivar with more tartaric acid and citric acid exuded from roots during the grain-filling period. The cultivar with more lactic acid in exudates had smaller gel consistency and alkali spreading values, but had greater amylose content. When roots were treated with exogenous ZR, ABA, and ACC during grain filling, effects of the chemicals on the rice quality were consistent with the relationships of the endogenous hormones （Z ＋ ZR, ABA, and ACC） with the quality indexes. Using rape cake as organic fertilizer can increase the concentrations of malic acid and succinic acids exuded from roots as well as the breakdown value in starch profile and reduce the setback value. The results suggest that root chemical signals play important roles in the formation of rice quality, and dee quality could be improved through regulating the signals.
文摘The interplanting with zero-tillage of rice, i.e. direct sowing rice 10-20 days before wheat harvesting, and remaining about 30-cm high stubble after cutting wheat or rice with no tillage, is a new cultivation technology in wheat-rice rotation system. To study the effects of interplanting with zero tillage and straw manure on rice growth and quality, an experiment was conducted in a wheat-rotation rotation system. Four treatments, i.e. ZIS （Zero-tillage, straw manure and rice interplanting）, Zt （Zero-tillage, no straw manure and rice interplanting）, PTS （Plowing tillage, straw manure and rice transplanting）, and PT （Plowing tillage, no straw manure and rice transplanting）, were used. ZtS reduced plant height, leaf area per plant and the biomass of rice plants, but the biomass accumulation of rice at the late stage was quicker than that under conventional transplanting cultivation. In the first year （2002）, there was no significant difference in rice yield among the four treatments. However, rice yield decreased in interplanting with zero-tillage in the second year （2003）. Compared with the transplanting treatments, the number of filled grains per panicle decreased but l000-grain weight increased in interplanting with zero-tillage, which were the main factors resulting in higher yield, tnterplanting with zero-tillage improved the milling and appearance qualities of rice. The rates of milled and head rice increased while chalky rice rate and chalkiness decreased in interplanting with zero-tillage. Zero-tillage and interplanting also affected rice nutritional and cooking qualities. In 2002, ZIS showed raised protein content, decreased amylose content, softer gel consistency, resulting in improved rice quality. In 2003, zero-tillage and interplanting decreased protein content and showed similar amylose content as compared with transplanting treatments. Moreover, protein content in PTS was obviously increased in comparison with the other three treatments. The rice in interplanting with zero-tillage treatments had higher peak viscosity and breakdown, lower setback, showing better rice taste quality. The straw manure had no significant effect on rice viscosity under interplanting with zero-tillage, but had the negative influence on the rice taste quality under transplanting with plowing tillage.
基金the National Key Research&Development Project of China(2016YFD0300501)the Key Project of Jiangxi Provincial Natural Science Foundation(20202ACBL215004)the Key Research of&Development Project Jiangxi Province,China(20171BBF60030).
文摘High temperature(HT)accompanied with strong light(SL)often occurs in early indica rice production during grout filling stage in Southern China,which accelerates grain ripening.Two indica rice cultivars with different amylose content(Zhongjiazao17,ZJZ17,high amylose content;Xiangzaoxian45,XZX45,low amylose content)were grown under control(CK),HT,and HT+SL conditions during grout filling to determine the effects on grain yield and quality of rice.The results showed that compared with CK,HT and HT+SL significantly reduced the 1000-grain weight and filled grain rate whether in high or low amylose content early indica rice cultivars during grout filling,resulting in a significantly lower grain yield.Meanwhile,HT and HT+SL significantly decreased the milled rice rate,brown rice rate and head rice rate,whereas significantly increased chalky rate and chalky degree;and breakdown decreased and setback,pasting temperature increased in the cultivars,leading to the poor processing,appearance and cooking and eating quality of early indica rice cultivars.Compared with HT,the yield of ZJZ17 was significantly decreased under HT+SL,due to the lower 1000-grain weight.However,the effect of HT+SL on rice quality varied in the cultivars.In general,the yield and rice quality of ZJZ17 were relatively poor under HT+SL.Our results suggested that HT and HT+SL during grout filling had significant damage to the yield and quality of early indica rice cultivars,especially HT+SL,while the high amylose cultivar ZJZ17 showed a higher negative effect under HT+SL.
基金Supported by China Tobacco Yunnan Industrial Co.,Ltd(2010YL02)~~
文摘[Objective] The aim was to explore tobacco varieties which satisfy tobacco formula and is suitable to be grown in ecotopes simultaneously. [Method] Interior and exterior qualities of tobacco were compared and identified based on agronomic and economic characters of tobacco in fields. [Result] Yunshai No.1 was better in both agronomic and economic characters. Specifically, the fragrance was dominated by empyreumatique and aroma; the highly-qualified variety is fragrant and sweet, with little irritation, which gives the tobacco smoke a light, mild flavor. As for Virgini- a934, economic characters were better, but agronomic characters were just ordinary. Similar to Yunshai No.l, dominated by empyreumatique and aroma, the variety was with distinctive resin and herbaceous fragrance. What＇s more, it tasted good with high quality and usability. Cunsanpi was ordinary in agronomic characters, and poor in economic characters, with coordinated quality and chemical composition. It is fra- grant and the smoke is clean. However, the quality was not so high and it tasted not so good. Tengruan No.2 was good in agronomic characters, but poor in eco- nomic characters, which gives delicate fragrance, but not clean enough. Waiweiba and Mijie Qinggeng neither taste well nor smell sweet, performing ordinary in agro- nomic and economic characters. Hence, the two varieties seem bad in quality and ranks poorly. [Conclusion] In terms of sensory quality, the varieties from high to low were Yunshai No.1, Virginia 934, Cunsanpi, Tengruan No.2, Waiweiba and Mijie Qinggeng.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.31171485 and 31470086)the National High Technology Research and Development Program of China(Grant No.2014AA10A605)the National Science and Technology Supporting Program of China(Grant Nos.2012BAD04B08 and 2013BAD07B09)
文摘To select elite germplasms, 112 mutants derived from japonica rice cultivar Wuyujing 3 were evaluated. The yield components such as panicle number per square meter, grain number per panicle, and grain weight were measured. The quality traits such as percentage of chalky grains（PCG）, brown rice yield（BRY）, milled rice yield（MRY）, degree of milling（DM）, amylose content（AC）, protein content（PC）, and relationships among traits were inverstigated. Results showed that grain yield ranged from 2.15 to 12.49 t/hm2 with a mean of 6.4 t/hm2 and number of grains per square meter contributed for 94.64% in grain yield variation. For quality traits, all rice mutants had short size（grain length ≤ 5.5 mm） and bold shape（grain length to width ratio = 1.10-2.00）. Most of rice mutants（87.5%） had PCG values below 20%. All mutants had MRY values above 50%, AC values below 20%, and PC values below 10%. Percentage of chalky grains was significantly negatively correlated with MRY and positively correlated with DM. BRY and MRY were significantly negatively correlated with DM. PC was significantly and positively correlated with MRY and negatively correlated with DM, while AC had no significant correlation with these quality traits. It was concluded that there were 25 rice mutants which fulfilled the major requirements of Jiangsu standard japonica rice such as low percentage of chalky grains, low amylose content, optimal protein content, and which could be used as elite germplasms. Thus the mutants identified may lead to significant progress in improvement of rice quality.
基金Supported by Special Project for Shanghai and Anhui Modern Tobacco Agricultural High-tech Demonstration Park(CF56.1-ZJ1)~~
文摘[Objective] The aim of this study was to evaluate the effects of soil amend- ment composed of biochar and inorganic mineral material on growth and develop- ment, yield and output value of flue-cured tobacco in South Anhui Province. [Method] A field plot experiment was conducted. The agronomic traits, yield and output value, as well as appearance quality and flavor of flue-cured tobacco were evaluated. [Re- suit] The soil amendments composed of biochars and inorganic mineral materials could significantly increase plant height, stem diameter, leaf size, yield and output of flue-cured tobacco, as well as proportion of first-grade tobacco leaves at the middle and late growth period. The yield in the X3 treatment group （70% T20 ＋ 30% ZC） was highest, and it was higher than that in the control group by 398 kg/hm2. Com- pared with that in the control group, the output of flue-cured tobacco in the X3 treatment group was increased by 10 290 yuan/hm2. In terms of appearance quality and flavor, the flue-cured tobacco leaves in the soil amendment treatment groups were all better than those in the control group. [Conclusion] The application of soil amendment composed of biochar and inorganic mineral material is an effective mea- sure to improve tobacco-growing soil, promote tobacco growth and development, im- prove tobacco yield and output and improve tobacco leaf quality in South Anhui re- gion.
基金supported by Science and Technology Major Project of Hubei Province in China(No.2021AFB001)。
文摘In laser wakefield acceleration,injecting an external electron beam at a certain energy is a promising approach for achieving a high-quality electron beam with low energy spread and low emittance.In this paper,the process of laser wakefield acceleration with an external injection at 10 pC has been studied in simulations.A Bayesian optimization method is used to optimize the key laser and plasma parameters so that the electron beam is accelerated to the expected energy with a small emittance and energy spread growth.The effect of the rising edge of the plasma on the transverse properties of the electron beam is simulated and optimized in order to ensure that the external electron beam is injected into the plasma without significant emittance growth.Finally,a high-quality electron beam with an energy of 1.5 GeV,a normalized transverse emittance of 0.5 mm·mrad and a relative energy spread of 0.5%at 10 pC is obtained.
基金国家重点基础研究发展计划(973计划)，国家自然科学基金，Foundation on Ministry of Education in China
文摘Improving grain quality, which is composed primarily of the appearance of the grain and its cooking and milling attributes, is a major objective of many rice-producing areas in China. In the present study, we conducted a marker-based genetic analysis of the appearance and milling quality of rice （Oryza sativa L.） grains using a doubled-haploid population derived from a cross between the indica inbred Zhenshan 97 strain and the japonica inbred Wuyujing 2 strain. Quantitative trait locus （QTL） analysis using a mixed linear model approach revealed that the traits investigated were affected by one to seven QTLs that individually explained 4.0%-30.7% of the phenotypic variation. Cumulatively, the QTL for each trait explained from 12.9% to 61.4% of the phenotypic variation. Some QTLs tended to have a pleiotropic or location-linked association as a cause of the observed phenotypic correlations between different traits. Improvement of the characteristics of grain appearance and grain weight, as well as an improvement in the milling quality of rice grains, would be expected by a recombination of different QTLs using marker-assisted selection.
