ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice （Nanjing 44）. MethodThe rice seeds were soaked in 0 （water as a control）, 1, 2, 4 and 6 ...ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice （Nanjing 44）. MethodThe rice seeds were soaked in 0 （water as a control）, 1, 2, 4 and 6 g/L fulvic acid （FA） before sowed. Then, the rice morphological indices, leaf chlorophyll content, photosynthesis parameters, root activity and chlorophyll fluorescence parameters were measured in the following field studies. ResultCompared with the control, the leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance and dry matter weight and some fluorescence parameters such as the maximum photochemical efficiency of photosystem II （PSII） （Fv/Fm）, excitation energy capture efficiency of opened PSII reaction center （Fv’/Fm’） and efficiency of the open reaction centre （ΦPS II） increased by different levels at both jointing stage and heading stage of direct seeding rice, whose seeds were soaked by FA with different concentrations. High FA concentration （4-6 g/L） significantly increased the cultivated rice leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance, transpiration rate and dry matter weight by 10.32% -22.88% , 5.88% -13.11% , 12.16% -26.84% , 11.43% -88.46% , 10.63% -21.63% , 18.49% -19.68% , respectively, thereby improving the physiological function and light energy transform efficiency of rice at the growth stage. With FA concentration increasing, the yield, effective panicles, grain number per panicle and seed setting rate were increased significantly compared with the control by 17.52%-18.71%, 3.46%-3.85%, 6.30%- 6.51% and 7.82%-8.69% respectively. ConclusionSoaking rice seed with FA could be considered as an effective way to improve the rice competitiveness at early growth stage.展开更多
Field trials on a silt-loamy paddy soil derived from shallow-sea deposit in direct seeding rice fields were conducted in Zhejiang, China, in 1996 to compare N efficiency of controlled release fertilizers (LP fertilize...Field trials on a silt-loamy paddy soil derived from shallow-sea deposit in direct seeding rice fields were conducted in Zhejiang, China, in 1996 to compare N efficiency of controlled release fertilizers (LP fertilizers) with the conventional urea. Six treatments including CK (no N fertilizer), conventional urea and different types of LP fertilizers at different rates were designed for two succeeding crops of early and late rice. A blend of different types of LP fertilizers as a single preplant "co-situs" application released N in a rate and amount synchronizing with uptake pattern of direct seeding rice. A single preplant application of the LP fertilizers could meet the N requirement of rice for the whole growth period without need of topdressing. Using LP fertilizer blends, equivalent grain yields could be maintained even if the N fertilization rates were reduced by 25%～50% compared with the conventional urea. Agronomic efficiency of the LP fertilizers was 13.6%～ 86.4% higher than that of the conventional urea in early rice and 100%～164.1% in late rice, depending on the amounts of the LP fertilizers applied. N fertilizer recovery rate increased from 27.4% for the conventional application of urea to 41.7%～54.l% for the single preplant "co-situs" application of the LP fertilizers. Use of the LP fertilizers was promising if the increase in production costs due to the high LP fertilizer prices could be compensated by increase in yield and N efficiency, reduction in labor costs and improvement in environment.展开更多
Structure and sowing principles of rice rope direct seeding machine are introduced. In order to test the machine＇ s working performance, such as compacting effect, sowing depth, influence of sowing device to rice rop...Structure and sowing principles of rice rope direct seeding machine are introduced. In order to test the machine＇ s working performance, such as compacting effect, sowing depth, influence of sowing device to rice rope, etc., field experiments were conducted. It is concluded that mean slip ratio of compacting wheel 1 is 4.44%, wheel 2 is 5.58%, wheel 3 is 7.81%, and wheel 4 is 6.96%; mean depth of planting is 29.72 mm, and mean variability coefficient of planting depth is 6.39%. Maximum variability coefficient of planting depth is 8.40%. Rice rope＇s snapping is closely related with the machine＇s speed and guide thread wheel by sowing device orthogonal experiments. Test results show that the machine has a rational design, safe work and meets to the requirements of planting. This study has laid the foundation for further studying the project.展开更多
Chemical weeding in dry direct seeding fields of single cropping middle-late rice was studied in Huida vegetable farm of Huizhou City in 2012. The main treatment was herbicide（ pretilachlor ＋ bensulfuron-methyl,Yang...Chemical weeding in dry direct seeding fields of single cropping middle-late rice was studied in Huida vegetable farm of Huizhou City in 2012. The main treatment was herbicide（ pretilachlor ＋ bensulfuron-methyl,Yangguo and butachlor）,and the sub-treatment was application method（ soil treatments,seedling treatment and integrated treatment）. The results showed that 80 g pretilachlor ＋ bensulfuron-methyl（ 36% pretilachlor ＋ 4% bensulfuron-methyl） diluted with 50 kg water could be sprayed or 200 g Yangguo（ 23. 9% butachlor ＋ 1. 1% bensulfuron-methyl） mixed with 15 kg sandy soil could be broadcasted per 667 m2 on the sowing day or the second day under moist condition of soil,which could effectively control weeds in dry direct seeding fields of single cropping middle-late rice.展开更多
The research used bioassay method to explore seed tolerance of Cd in terms of seed germination and seedling growth. Specifically, 12 rice varieties of three types were investigated under Cd stress, covering germinatio...The research used bioassay method to explore seed tolerance of Cd in terms of seed germination and seedling growth. Specifically, 12 rice varieties of three types were investigated under Cd stress, covering germination rate, shooting index, vigor index, seedling and shoot lengths, and fresh weights. The results showed that as Cd concentration grew, seed germination and seedling growth kept increasingly inhibited; germination index, vigor index, root length, shoot length and fresh weights went down; inhibition effects on seed germination and seedling growth were conventional rice〉two-line hybrid rice〉three-line hybrid ,rice. Shanyou 9588, Tianyou 998, Chuanxiang 8, and Y Liangyou 1 performed ~rongly in Cd tolerance; C Liangyou 651, Nei 5 You 263, Xiangwanxian 16, Huanghuazhan, Xiangwanxian 13, and Zhunliangyou 527 performed poorly in Cd tolerance, and Cd tolerance of rest treatments were moderate.展开更多
[Objective] The aim was to introduce the development and application of 2BDQ-8 rice direct sowing machine and provide a theoretical basis for rice mechanization production. [Method] 2BDQ-8 rice direct sowing machine w...[Objective] The aim was to introduce the development and application of 2BDQ-8 rice direct sowing machine and provide a theoretical basis for rice mechanization production. [Method] 2BDQ-8 rice direct sowing machine was used for the promotion test in field of several cities and counties in Jiangsu Province,and artificial rice planting and mechanization rice planting were compared to explore the production and economic situation. [Result] 2BDQ-8 rice direct sowing machine had advantages such as high efficiency and low cost,the rice direct sowing machine saved about 30% compared to the artificial rice planting and mechanization rice planting,and the overall efficiency was significant. [Conclusion] 2BDQ-8 rice sowing machine was a production technology that had low cost and high efficiency,which should be widely applied.展开更多
The great progress in super rice breeding both in China and other countries has been made in recent years. However, there were three main problems in super rice breeding： 1） the super rice varieties were still rare...The great progress in super rice breeding both in China and other countries has been made in recent years. However, there were three main problems in super rice breeding： 1） the super rice varieties were still rare; 2） most super rice varieties exhibited narrow adaptability; and 3） current breeding theories emphasized too much on the rice growth model, but they were unpractical in guidance for rice breeding. According to the authors＇ experience on the rice breeding, the breeding strategies including three steps （super parent breeding, super hybrid rice breeding and super hybrid rice seed production） were proposed, and the objectives of each step and the key technologies to achieve the goals were elucidated in detail. The super parent of hybrid rice should exhibit excellent performance in all agronomic traits, with the yield or sink capacity reached the level of the hybrid rice control in regional trials. The super hybrid rice combination should meet the following criteria： good rice quality, wide adaptation, lodging resistance, resistance to main insects and diseases, and the yield exceeded above 8% over the control varieties in the national and provincial regional trials. To achieve the goal, the technical strategies, such as selecting optimal combination of the parents, increasing selection pressure, paying more attention to harmony of ideal plant type, excellent physiological traits and all the agronomic traits, should be emphasized. The yield of seed production should reach 3.75 t/ha and 5.25 t/ha for the super hybrid rice combinations derived from early-season and middle-season types of male sterile lines, respectively. The main technologies for raising seed production yield included selecting optimum seed production site, using the male sterile line with large sink capacity and good outcrossing characteristics, and improving the amount of the pollen by intensive cultivation of the male parent. According to the technologies of the three-step breeding on super hybrid rice, two super rice parents, including a male parent 996 and a thermo（photo）-genic male sterile [T（P）GMS] line C815S, were bred. Furthermore, a super early hybrid rice combination, Luliangyou 996, which could be used as a double-season early rice variety in middle and lower reaches of the Yangtze River, China, was bred by using the super rice varlet3, 996 as the male parent, and several hybrid rice combinations with higher yield than control variety in regional trials both of Hunan Province and state were bred with the T（P）GMS line C815S as the female parent.展开更多
Lipoxygenase （LOX, EC1.13.11.12） is a key enzyme during the degradation of lipids in animals and even plants, and also the first key enzyme responsible for the biosynthesis of jasmonate. To purify and characterize t...Lipoxygenase （LOX, EC1.13.11.12） is a key enzyme during the degradation of lipids in animals and even plants, and also the first key enzyme responsible for the biosynthesis of jasmonate. To purify and characterize the OsLOX1 gene from rice seeds, the entire coding region of the OsLOX1 gene was inserted into an expression vector pET30a（＋） and transformed into Escherichia coil BL21 （DE3）. Expression of the fusion protein was successfully induced by isopropyl-β-D- thiogalactopyranoside （IPTG） and the purified recombinant protein was obtained by His.Bind Kits. Further assay showed that the purified recombinant protein exhibited the LOX activity. The optimum pH was 4.8 （acetate buffer） and the optimum temperature was 30℃ for the above enzyme. Thus, the recombinant might confer an available usage for the synthesis of jasmonate in vitro, and also provides a possibility for elucidating the inter-relationship between the primary structure of the plant seed lipoxygenase protein and its physiological functions.展开更多
With the use of a seed washing technique, more than 4000 Gram negative bacteria were isolated by two improved isolation methods from 446 batches of 1 kg rice seed samples obtained from 22 provinces in the Philippines....With the use of a seed washing technique, more than 4000 Gram negative bacteria were isolated by two improved isolation methods from 446 batches of 1 kg rice seed samples obtained from 22 provinces in the Philippines. They were initially characterized on the basis of colony morphology and results of biochemical and pathogenicity tests. Six hundred and fifty two strains were further identified by Biolog, from which 133 were selected for fatty acid methyl ester (FAME) analysis together with 80 standard reference!strains. Sixteen species or types of Pseudomonas and 17 genera of non pseudomonads were identified, more than one third of which have not been recorded in rice. The most predominant species observed were P. putida and P. fulva. About 17% of the strains of Pseudomonas and 2% of the non pseudomonads were antagonistic to one or more fungal or bacterial pathogens of rice. Rice seed is an important source of biological control agents.展开更多
The purpose was to define the control efficiency and safety of 20% cy- halofop-butyl WP on grass weeds in direct seeded rice fields, in order to provide the basis for chemical weeding. This study measured Leptochloa c...The purpose was to define the control efficiency and safety of 20% cy- halofop-butyl WP on grass weeds in direct seeded rice fields, in order to provide the basis for chemical weeding. This study measured Leptochloa chinensis（L.） Nees, Echinoch/oa crusgalli （L.） Beauv and other gramineous weed control efficiency with four concentrations of 20% cyhalofop-dutyl WP and 100 g/L cyhalofop-dutyl EC in direct seeded rice fields, and analyzed the yield-increasing effect and safety of rice. The results showed that 20% cyhalofop-butyl WP had a good control efficiency on grass weeds such as Leptochloa chinensis（L.） Nees, Echinoch/oa crusgalli（L.） Beauv and other grasses. The effective dosage of 90-150 g/hm2 was over 90.7% on Lep- foch/oa chinensis（L.） Nees and the comprehensive control effect of the grass weeds was above 86.7%, which was basically consistent with 100 g/L cyhalofop-dutyl EC. Furthermore, 20% cyhalofop-dutyl WP was high security for direct seeded rice fields. The yield of rice was increased by 10.18%-11.22% after spraying herbicide. There- fore, 20% of cyhalofop-dutyl WP can be used as a special herbicide for controlling Leptochloa chinensis（L.） Beauv in direct seeded rice fields, and has a good applica- tion prospect.展开更多
Ultraweak chemiluminescence(UCL)is the sponta-neous light emission radiated from various biological sys-tems derived from chemiexcitation of biological molecules during oxidative metabolicprocesses(Popp et al,1988).Th...Ultraweak chemiluminescence(UCL)is the sponta-neous light emission radiated from various biological sys-tems derived from chemiexcitation of biological molecules during oxidative metabolicprocesses(Popp et al,1988).Therefore,this weak light is a possible representation of physiological or pathological conditions of cells and tis-sues.Detection of UCL makes it possible to acquire im-mediate information on biological activities non-invasively(Popp et al,1988).The most important aspect of the chemiluminescence(CL)in biological systems is that it gives readily detectable,continuously monitorable,non-invasive signals of oxidative metabolism.展开更多
Traditional rice seed germination rate detection methods have low efficiency,poor accuracy and high specialization.The paper proposed a novel method by using fluorescent spectrometry combined with Deep Belief Network(...Traditional rice seed germination rate detection methods have low efficiency,poor accuracy and high specialization.The paper proposed a novel method by using fluorescent spectrometry combined with Deep Belief Network(DBN)to establish forecasting model for rice seed germination rate.Firstly,two varieties of seeds,Lianjing 7 and Wuyunjing,with 0~7 artificial aged days separately were soaked intopurified water for 5~30 minutes with every 5 minutes'interval.Then the fluorescence spectrums of the soak solutions were detected using fluorescence spectrometer.In addition,the spectrum data were centralized and then denoised with Ensemble Empirical Mode Decomposition(EEMD).The characteristic fluorescence wavelength of 441.5nm was extracted using Principal Component Anamysis(PCA).Finally,the rice seed germination predicting models were establishee with Partial Least Squares Regression(PLSR),Back Propagation Neural Network(BPNN),Radial Basis Function Neural Network(RBFNN)and Deep Belief Network(DBN),respectively.The results showed that the accuracy of DBN model was the highest in the case ofless data and weak signal,and R p=0.9792,RMSEP=0.101.At the same time,we got the best soaking time is 22.1 min by analyzing the changing trend of mixed rice seed fluorescent data Rp,actually,it took about 5 min to get the accuracy more than 0.95(R p).The research results demonstrated the feasibility and high accuracy for predicting rice seed germination rate non-invasively by combining the fluorescent spectrometry and EEMD-DBN model,moreover,itadapts to the detection of rice seeds with different colors and contaminated levels.展开更多
A machine vision system was developed to inspect the quality of rice seeds. Five varieties of Jinyou402, Shanyou10, Zhongyou207, Jiayou and IIyou were evaluated. The images of both sides of rice seed with black backg...A machine vision system was developed to inspect the quality of rice seeds. Five varieties of Jinyou402, Shanyou10, Zhongyou207, Jiayou and IIyou were evaluated. The images of both sides of rice seed with black background and white background were acquired with the image processing system for identifying external features of rice seeds. Five image sets consisting of 600 original images each were obtained. Then a digital image processing algorithm based on Hough transform was developed to inspect the rice seeds with incompletely closed glumes. The algorithm was implemented with all image sets using a Matlab 6.5 procedure. The results showed that the algorithm achieved an average accuracy of 96% for normal seeds, 92% for seeds with fine fissure and 87% for seeds with incompletely closed glumes. The algorithm was proved to be applicable to different seed varieties and insensitive to the color of the background.展开更多
Dry seeding is a resource-saving rice establishment method. With an equivalent yield, dry seeded flooded rice （DSR） has been considered as a replacement for traditional transplanted flooded rice （TFR）. However, th...Dry seeding is a resource-saving rice establishment method. With an equivalent yield, dry seeded flooded rice （DSR） has been considered as a replacement for traditional transplanted flooded rice （TFR）. However, the differences in leaf and root senescence during grain filling between DSR and TFR were seldom identified. In this study, the root length, root tip number and leaf senescence of rice varieties Huanghuazhan and Yangliangyou 6 during ripening were compared between DSR and TFR. Results showed that top three leaves in DSR had the characteristics of relatively lower SPAD value, lower N content and premature leaf senescence. In addition, both the total root length and total root tip number of DSR were significantly lower than those of TFR. In conclusion, premature and quick leaf senescence was related with inadequate root length and root tip number during ripening, which might result from the deficiency of nitrogen supply in DSR. Techniques on improving leaf nitrogen status and delaying the leaf senescence during grain-filling in DSR should be developed in future researches.展开更多
A digital image analysis algorithm based color and morphological features was developed to identify the six varieties （ey7954, syz3, xsl 1, xy5968, xy9308, z903） rice seeds which are widely planted in Zhejiang Provi...A digital image analysis algorithm based color and morphological features was developed to identify the six varieties （ey7954, syz3, xsl 1, xy5968, xy9308, z903） rice seeds which are widely planted in Zhejiang Province. Seven color and fourteen morphological features were used for discriminant analysis, Two hundred and forty kernels used as the training data set and sixty kernels as the test data set in the neural network used to identify rice seed varieties. When the model was tested on the test data set, the identification accuracies were 90.00%, 88.00%, 95.00%, 82.00%, 74.00%, 80.00% for ey7954, syz3, xsl1, xy5968, xy9308, z903 respectively.展开更多
A survey on isolation and detection of the casual organism of bacterial grain rot of rice was conducted during 1997-2006. In 2006, six pathogenic bacterial strains were isolated from two symptomless seed samples of ri...A survey on isolation and detection of the casual organism of bacterial grain rot of rice was conducted during 1997-2006. In 2006, six pathogenic bacterial strains were isolated from two symptomless seed samples of rice （Oryza sativa L.） originally produced in Hainan Province and then planted in Zhejiang Province, China. They were identified as Burkholderia glumae which is the causal organism of bacterial grain rot of rice by physiological characteristics, colony morphology, pathogenicity test, Biolog, fatty acid methyl ester （FAME） analysis and RAPD-PCR compared with the four standard reference strains. It is confirmed that there is the infection of B. glumae in so-called ＇health looking seeds＇.展开更多
We studied the influence of seed priming with beta-amino butyric acid（BABA） on the growth, physiological and biochemical parameters of seedlings with varied abiotic stress tolerance, which were raised and grown unde...We studied the influence of seed priming with beta-amino butyric acid（BABA） on the growth, physiological and biochemical parameters of seedlings with varied abiotic stress tolerance, which were raised and grown under unstressed and stressed（NaCl/PEG-6000） conditions. Under stressed conditions, the growth of rice seedlings was less when compared to control plants. After BABA priming, the seedling growth increased both under unstressed and stressed conditions as compared to the respective controls. BABA priming of rice seeds caused increase in the photosynthetic pigment content of the leaves, modified the chlorophyll a fluorescence related parameters and also enhanced the photosystem activities of seedlings when compared to their respective non-primed controls. BABA priming also caused increased mitochondrial activities of the rice seedlings. Moreover, BABA priming significantly reduced malondialdehyde content in the seedlings and also resulted in accumulation of proline especially in the NaCl tolerant variety Vyttila 6. BABA seed priming also enhanced the activity of nitrate reductase enzyme and activities of antioxidant enzymes like guaiacol peroxidase and superoxide dismutase. The presence of BABA was detected by high performance thin layer chromatography analysis in the rice seeds whereas in the seedlings it was not detected. Thus, it can be inferred that the seed priming effect of BABA mainly occurred within the seeds, which was further carried to the seedlings. It is concluded that BABA priming of seeds improved the drought and salinity stress tolerance of all the three rice varieties and it was significantly evident in the drought tolerant variety Vaisakh and NaCl tolerant variety Vyttila 6, when compared to the stress sensitive variety Neeraja.展开更多
We developed a computerized seed identification system. Fifteen rice varietiesthat were widely used in China were analyzed by AFLP fingerprinting. 12 primerpairs were screened, In order to simplify the procedure and c...We developed a computerized seed identification system. Fifteen rice varietiesthat were widely used in China were analyzed by AFLP fingerprinting. 12 primerpairs were screened, In order to simplify the procedure and cut down the cost inseed identification. the least number of primer pairs for practical seed identifi-cation should be seleeled. In this study. 3 primer pairs were selected. They展开更多
The effect of La(NO3)(3) on natural or artificial aged rice seeds vigor was studied. The results show that the germination rate, germination index and vigor index of aged rice seed increase. Activities of superoxide d...The effect of La(NO3)(3) on natural or artificial aged rice seeds vigor was studied. The results show that the germination rate, germination index and vigor index of aged rice seed increase. Activities of superoxide dismutase, catalase and peroxidase are enhanced. . O-2(-) and malond ialdehyde contents decrease in germinating stage of aged rice seed, and cell membrane permeability of aged rice seeds reduces by treating with La(NO3)(3). The vigor increase of rice natural aged seed is greater than that of artificial aged rice seeds by treating with La(NO3)(3).展开更多
The relation between seed viability and waterstatus in seed was studied.The experimentwas carried out at Zhongshan University.Seeds of hybrid rice Shanyou 63 were collectedfrom Guangdong Academy of Agriculture Sci-enc...The relation between seed viability and waterstatus in seed was studied.The experimentwas carried out at Zhongshan University.Seeds of hybrid rice Shanyou 63 were collectedfrom Guangdong Academy of Agriculture Sci-ences in 1993 and then stored for one year inopen air or with silica gel.Before and afterstorage,the relative content of free water andbound water in seeds were measured with展开更多
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201303022)National Key Technology Research and Development Program during the 12th Five-Year Plan Period(2012BAD19B02)~~
文摘ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice （Nanjing 44）. MethodThe rice seeds were soaked in 0 （water as a control）, 1, 2, 4 and 6 g/L fulvic acid （FA） before sowed. Then, the rice morphological indices, leaf chlorophyll content, photosynthesis parameters, root activity and chlorophyll fluorescence parameters were measured in the following field studies. ResultCompared with the control, the leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance and dry matter weight and some fluorescence parameters such as the maximum photochemical efficiency of photosystem II （PSII） （Fv/Fm）, excitation energy capture efficiency of opened PSII reaction center （Fv’/Fm’） and efficiency of the open reaction centre （ΦPS II） increased by different levels at both jointing stage and heading stage of direct seeding rice, whose seeds were soaked by FA with different concentrations. High FA concentration （4-6 g/L） significantly increased the cultivated rice leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance, transpiration rate and dry matter weight by 10.32% -22.88% , 5.88% -13.11% , 12.16% -26.84% , 11.43% -88.46% , 10.63% -21.63% , 18.49% -19.68% , respectively, thereby improving the physiological function and light energy transform efficiency of rice at the growth stage. With FA concentration increasing, the yield, effective panicles, grain number per panicle and seed setting rate were increased significantly compared with the control by 17.52%-18.71%, 3.46%-3.85%, 6.30%- 6.51% and 7.82%-8.69% respectively. ConclusionSoaking rice seed with FA could be considered as an effective way to improve the rice competitiveness at early growth stage.
文摘Field trials on a silt-loamy paddy soil derived from shallow-sea deposit in direct seeding rice fields were conducted in Zhejiang, China, in 1996 to compare N efficiency of controlled release fertilizers (LP fertilizers) with the conventional urea. Six treatments including CK (no N fertilizer), conventional urea and different types of LP fertilizers at different rates were designed for two succeeding crops of early and late rice. A blend of different types of LP fertilizers as a single preplant "co-situs" application released N in a rate and amount synchronizing with uptake pattern of direct seeding rice. A single preplant application of the LP fertilizers could meet the N requirement of rice for the whole growth period without need of topdressing. Using LP fertilizer blends, equivalent grain yields could be maintained even if the N fertilization rates were reduced by 25%～50% compared with the conventional urea. Agronomic efficiency of the LP fertilizers was 13.6%～ 86.4% higher than that of the conventional urea in early rice and 100%～164.1% in late rice, depending on the amounts of the LP fertilizers applied. N fertilizer recovery rate increased from 27.4% for the conventional application of urea to 41.7%～54.l% for the single preplant "co-situs" application of the LP fertilizers. Use of the LP fertilizers was promising if the increase in production costs due to the high LP fertilizer prices could be compensated by increase in yield and N efficiency, reduction in labor costs and improvement in environment.
基金supported by the National Natural Science Foundation of China(50775150)
文摘Structure and sowing principles of rice rope direct seeding machine are introduced. In order to test the machine＇ s working performance, such as compacting effect, sowing depth, influence of sowing device to rice rope, etc., field experiments were conducted. It is concluded that mean slip ratio of compacting wheel 1 is 4.44%, wheel 2 is 5.58%, wheel 3 is 7.81%, and wheel 4 is 6.96%; mean depth of planting is 29.72 mm, and mean variability coefficient of planting depth is 6.39%. Maximum variability coefficient of planting depth is 8.40%. Rice rope＇s snapping is closely related with the machine＇s speed and guide thread wheel by sowing device orthogonal experiments. Test results show that the machine has a rational design, safe work and meets to the requirements of planting. This study has laid the foundation for further studying the project.
基金Supported by National Science and Technology Support Program(2007BAD89B14)Special Fund for Agro-scientific Research in the PublicInterest(00803028)+3 种基金Major Technical Research Project of Ministry of Agriculture for Agricultural Structure Adjustment(06-03-07B)Project ofGuangdong Provincial Finance Department(YCY[2005]No.11,YCJ[2006]No.187)Agricultural Research Project of Guangdong ProvincialScience and Technology Department(2005B20101001)Special Fund forAgro-scientific Research in the Public Interest(201103001)
文摘Chemical weeding in dry direct seeding fields of single cropping middle-late rice was studied in Huida vegetable farm of Huizhou City in 2012. The main treatment was herbicide（ pretilachlor ＋ bensulfuron-methyl,Yangguo and butachlor）,and the sub-treatment was application method（ soil treatments,seedling treatment and integrated treatment）. The results showed that 80 g pretilachlor ＋ bensulfuron-methyl（ 36% pretilachlor ＋ 4% bensulfuron-methyl） diluted with 50 kg water could be sprayed or 200 g Yangguo（ 23. 9% butachlor ＋ 1. 1% bensulfuron-methyl） mixed with 15 kg sandy soil could be broadcasted per 667 m2 on the sowing day or the second day under moist condition of soil,which could effectively control weeds in dry direct seeding fields of single cropping middle-late rice.
基金Supported by Loudi City Science and Technology Project(2014-1)State Key Laboratory of Hybrid RiceKey Laboratory of Pesticide Harmless Application of Hunan Province~~
文摘The research used bioassay method to explore seed tolerance of Cd in terms of seed germination and seedling growth. Specifically, 12 rice varieties of three types were investigated under Cd stress, covering germination rate, shooting index, vigor index, seedling and shoot lengths, and fresh weights. The results showed that as Cd concentration grew, seed germination and seedling growth kept increasingly inhibited; germination index, vigor index, root length, shoot length and fresh weights went down; inhibition effects on seed germination and seedling growth were conventional rice〉two-line hybrid rice〉three-line hybrid ,rice. Shanyou 9588, Tianyou 998, Chuanxiang 8, and Y Liangyou 1 performed ~rongly in Cd tolerance; C Liangyou 651, Nei 5 You 263, Xiangwanxian 16, Huanghuazhan, Xiangwanxian 13, and Zhunliangyou 527 performed poorly in Cd tolerance, and Cd tolerance of rest treatments were moderate.
基金Supported by the Subprogram " the Mechanization Development of High Speed Rice Sowing-Rice Direct Sowing Machine" of the Programs of Science Research for the "10th Five-year Plan" of MinistryScience and Technology (2001BA504B01-02)~~
文摘[Objective] The aim was to introduce the development and application of 2BDQ-8 rice direct sowing machine and provide a theoretical basis for rice mechanization production. [Method] 2BDQ-8 rice direct sowing machine was used for the promotion test in field of several cities and counties in Jiangsu Province,and artificial rice planting and mechanization rice planting were compared to explore the production and economic situation. [Result] 2BDQ-8 rice direct sowing machine had advantages such as high efficiency and low cost,the rice direct sowing machine saved about 30% compared to the artificial rice planting and mechanization rice planting,and the overall efficiency was significant. [Conclusion] 2BDQ-8 rice sowing machine was a production technology that had low cost and high efficiency,which should be widely applied.
文摘The great progress in super rice breeding both in China and other countries has been made in recent years. However, there were three main problems in super rice breeding： 1） the super rice varieties were still rare; 2） most super rice varieties exhibited narrow adaptability; and 3） current breeding theories emphasized too much on the rice growth model, but they were unpractical in guidance for rice breeding. According to the authors＇ experience on the rice breeding, the breeding strategies including three steps （super parent breeding, super hybrid rice breeding and super hybrid rice seed production） were proposed, and the objectives of each step and the key technologies to achieve the goals were elucidated in detail. The super parent of hybrid rice should exhibit excellent performance in all agronomic traits, with the yield or sink capacity reached the level of the hybrid rice control in regional trials. The super hybrid rice combination should meet the following criteria： good rice quality, wide adaptation, lodging resistance, resistance to main insects and diseases, and the yield exceeded above 8% over the control varieties in the national and provincial regional trials. To achieve the goal, the technical strategies, such as selecting optimal combination of the parents, increasing selection pressure, paying more attention to harmony of ideal plant type, excellent physiological traits and all the agronomic traits, should be emphasized. The yield of seed production should reach 3.75 t/ha and 5.25 t/ha for the super hybrid rice combinations derived from early-season and middle-season types of male sterile lines, respectively. The main technologies for raising seed production yield included selecting optimum seed production site, using the male sterile line with large sink capacity and good outcrossing characteristics, and improving the amount of the pollen by intensive cultivation of the male parent. According to the technologies of the three-step breeding on super hybrid rice, two super rice parents, including a male parent 996 and a thermo（photo）-genic male sterile [T（P）GMS] line C815S, were bred. Furthermore, a super early hybrid rice combination, Luliangyou 996, which could be used as a double-season early rice variety in middle and lower reaches of the Yangtze River, China, was bred by using the super rice varlet3, 996 as the male parent, and several hybrid rice combinations with higher yield than control variety in regional trials both of Hunan Province and state were bred with the T（P）GMS line C815S as the female parent.
基金grants from the National Basic Research Program of China (Grant No. 2004CB2117204)the National High-tech Research and Development Program of China (Grant No. 2006AA100101)+1 种基金the National Program of Science Technology and Tackle Key Problem of Chinathe Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT) of China
文摘Lipoxygenase （LOX, EC1.13.11.12） is a key enzyme during the degradation of lipids in animals and even plants, and also the first key enzyme responsible for the biosynthesis of jasmonate. To purify and characterize the OsLOX1 gene from rice seeds, the entire coding region of the OsLOX1 gene was inserted into an expression vector pET30a（＋） and transformed into Escherichia coil BL21 （DE3）. Expression of the fusion protein was successfully induced by isopropyl-β-D- thiogalactopyranoside （IPTG） and the purified recombinant protein was obtained by His.Bind Kits. Further assay showed that the purified recombinant protein exhibited the LOX activity. The optimum pH was 4.8 （acetate buffer） and the optimum temperature was 30℃ for the above enzyme. Thus, the recombinant might confer an available usage for the synthesis of jasmonate in vitro, and also provides a possibility for elucidating the inter-relationship between the primary structure of the plant seed lipoxygenase protein and its physiological functions.
文摘With the use of a seed washing technique, more than 4000 Gram negative bacteria were isolated by two improved isolation methods from 446 batches of 1 kg rice seed samples obtained from 22 provinces in the Philippines. They were initially characterized on the basis of colony morphology and results of biochemical and pathogenicity tests. Six hundred and fifty two strains were further identified by Biolog, from which 133 were selected for fatty acid methyl ester (FAME) analysis together with 80 standard reference!strains. Sixteen species or types of Pseudomonas and 17 genera of non pseudomonads were identified, more than one third of which have not been recorded in rice. The most predominant species observed were P. putida and P. fulva. About 17% of the strains of Pseudomonas and 2% of the non pseudomonads were antagonistic to one or more fungal or bacterial pathogens of rice. Rice seed is an important source of biological control agents.
基金Supported by Natural Science Foundation of Hunan Province(12JJ6026)Innovation Platform in Higher Educational Institutions of Hunan Province(14K053)Hunan Province Higher Educational Institutions Industrialization Program(13CY030)~~
文摘The purpose was to define the control efficiency and safety of 20% cy- halofop-butyl WP on grass weeds in direct seeded rice fields, in order to provide the basis for chemical weeding. This study measured Leptochloa chinensis（L.） Nees, Echinoch/oa crusgalli （L.） Beauv and other gramineous weed control efficiency with four concentrations of 20% cyhalofop-dutyl WP and 100 g/L cyhalofop-dutyl EC in direct seeded rice fields, and analyzed the yield-increasing effect and safety of rice. The results showed that 20% cyhalofop-butyl WP had a good control efficiency on grass weeds such as Leptochloa chinensis（L.） Nees, Echinoch/oa crusgalli（L.） Beauv and other grasses. The effective dosage of 90-150 g/hm2 was over 90.7% on Lep- foch/oa chinensis（L.） Nees and the comprehensive control effect of the grass weeds was above 86.7%, which was basically consistent with 100 g/L cyhalofop-dutyl EC. Furthermore, 20% cyhalofop-dutyl WP was high security for direct seeded rice fields. The yield of rice was increased by 10.18%-11.22% after spraying herbicide. There- fore, 20% of cyhalofop-dutyl WP can be used as a special herbicide for controlling Leptochloa chinensis（L.） Beauv in direct seeded rice fields, and has a good applica- tion prospect.
文摘Ultraweak chemiluminescence(UCL)is the sponta-neous light emission radiated from various biological sys-tems derived from chemiexcitation of biological molecules during oxidative metabolicprocesses(Popp et al,1988).Therefore,this weak light is a possible representation of physiological or pathological conditions of cells and tis-sues.Detection of UCL makes it possible to acquire im-mediate information on biological activities non-invasively(Popp et al,1988).The most important aspect of the chemiluminescence(CL)in biological systems is that it gives readily detectable,continuously monitorable,non-invasive signals of oxidative metabolism.
基金The National Natural Science Foundation of China Youth Foundation of China(11604154)the Three New Project of Agricultural Machinery in Jiangsu Province(SZ120170036)the Fundamental Research Funds for the Central Universities(KJQN2017011)
文摘Traditional rice seed germination rate detection methods have low efficiency,poor accuracy and high specialization.The paper proposed a novel method by using fluorescent spectrometry combined with Deep Belief Network(DBN)to establish forecasting model for rice seed germination rate.Firstly,two varieties of seeds,Lianjing 7 and Wuyunjing,with 0~7 artificial aged days separately were soaked intopurified water for 5~30 minutes with every 5 minutes'interval.Then the fluorescence spectrums of the soak solutions were detected using fluorescence spectrometer.In addition,the spectrum data were centralized and then denoised with Ensemble Empirical Mode Decomposition(EEMD).The characteristic fluorescence wavelength of 441.5nm was extracted using Principal Component Anamysis(PCA).Finally,the rice seed germination predicting models were establishee with Partial Least Squares Regression(PLSR),Back Propagation Neural Network(BPNN),Radial Basis Function Neural Network(RBFNN)and Deep Belief Network(DBN),respectively.The results showed that the accuracy of DBN model was the highest in the case ofless data and weak signal,and R p=0.9792,RMSEP=0.101.At the same time,we got the best soaking time is 22.1 min by analyzing the changing trend of mixed rice seed fluorescent data Rp,actually,it took about 5 min to get the accuracy more than 0.95(R p).The research results demonstrated the feasibility and high accuracy for predicting rice seed germination rate non-invasively by combining the fluorescent spectrometry and EEMD-DBN model,moreover,itadapts to the detection of rice seeds with different colors and contaminated levels.
基金Project supported by the National Natural Science Foundation ofChina (No. 60008001) and the Natural Science Foundation of Zhe-jiang Province (No. 300297), China
文摘A machine vision system was developed to inspect the quality of rice seeds. Five varieties of Jinyou402, Shanyou10, Zhongyou207, Jiayou and IIyou were evaluated. The images of both sides of rice seed with black background and white background were acquired with the image processing system for identifying external features of rice seeds. Five image sets consisting of 600 original images each were obtained. Then a digital image processing algorithm based on Hough transform was developed to inspect the rice seeds with incompletely closed glumes. The algorithm was implemented with all image sets using a Matlab 6.5 procedure. The results showed that the algorithm achieved an average accuracy of 96% for normal seeds, 92% for seeds with fine fissure and 87% for seeds with incompletely closed glumes. The algorithm was proved to be applicable to different seed varieties and insensitive to the color of the background.
基金supported by the National Natural Science Foundation of China(Grant No.31371571)the National High Technology Research and Development Program of China(863 Program)(Grant No.2014AA10A605)the Fundamental Research Funds for the Central Universities(Grant No.2662017JC001)
文摘Dry seeding is a resource-saving rice establishment method. With an equivalent yield, dry seeded flooded rice （DSR） has been considered as a replacement for traditional transplanted flooded rice （TFR）. However, the differences in leaf and root senescence during grain filling between DSR and TFR were seldom identified. In this study, the root length, root tip number and leaf senescence of rice varieties Huanghuazhan and Yangliangyou 6 during ripening were compared between DSR and TFR. Results showed that top three leaves in DSR had the characteristics of relatively lower SPAD value, lower N content and premature leaf senescence. In addition, both the total root length and total root tip number of DSR were significantly lower than those of TFR. In conclusion, premature and quick leaf senescence was related with inadequate root length and root tip number during ripening, which might result from the deficiency of nitrogen supply in DSR. Techniques on improving leaf nitrogen status and delaying the leaf senescence during grain-filling in DSR should be developed in future researches.
基金Project supported by the National Natural Science Foundation of China (No. 60008001) and the Natural Science Foundation ofZhejiang Province, China (No. 300297)
文摘A digital image analysis algorithm based color and morphological features was developed to identify the six varieties （ey7954, syz3, xsl 1, xy5968, xy9308, z903） rice seeds which are widely planted in Zhejiang Province. Seven color and fourteen morphological features were used for discriminant analysis, Two hundred and forty kernels used as the training data set and sixty kernels as the test data set in the neural network used to identify rice seed varieties. When the model was tested on the test data set, the identification accuracies were 90.00%, 88.00%, 95.00%, 82.00%, 74.00%, 80.00% for ey7954, syz3, xsl1, xy5968, xy9308, z903 respectively.
基金the National Natural Science Foundation of China (Grant No. 30671397)
文摘A survey on isolation and detection of the casual organism of bacterial grain rot of rice was conducted during 1997-2006. In 2006, six pathogenic bacterial strains were isolated from two symptomless seed samples of rice （Oryza sativa L.） originally produced in Hainan Province and then planted in Zhejiang Province, China. They were identified as Burkholderia glumae which is the causal organism of bacterial grain rot of rice by physiological characteristics, colony morphology, pathogenicity test, Biolog, fatty acid methyl ester （FAME） analysis and RAPD-PCR compared with the four standard reference strains. It is confirmed that there is the infection of B. glumae in so-called ＇health looking seeds＇.
文摘We studied the influence of seed priming with beta-amino butyric acid（BABA） on the growth, physiological and biochemical parameters of seedlings with varied abiotic stress tolerance, which were raised and grown under unstressed and stressed（NaCl/PEG-6000） conditions. Under stressed conditions, the growth of rice seedlings was less when compared to control plants. After BABA priming, the seedling growth increased both under unstressed and stressed conditions as compared to the respective controls. BABA priming of rice seeds caused increase in the photosynthetic pigment content of the leaves, modified the chlorophyll a fluorescence related parameters and also enhanced the photosystem activities of seedlings when compared to their respective non-primed controls. BABA priming also caused increased mitochondrial activities of the rice seedlings. Moreover, BABA priming significantly reduced malondialdehyde content in the seedlings and also resulted in accumulation of proline especially in the NaCl tolerant variety Vyttila 6. BABA seed priming also enhanced the activity of nitrate reductase enzyme and activities of antioxidant enzymes like guaiacol peroxidase and superoxide dismutase. The presence of BABA was detected by high performance thin layer chromatography analysis in the rice seeds whereas in the seedlings it was not detected. Thus, it can be inferred that the seed priming effect of BABA mainly occurred within the seeds, which was further carried to the seedlings. It is concluded that BABA priming of seeds improved the drought and salinity stress tolerance of all the three rice varieties and it was significantly evident in the drought tolerant variety Vaisakh and NaCl tolerant variety Vyttila 6, when compared to the stress sensitive variety Neeraja.
文摘We developed a computerized seed identification system. Fifteen rice varietiesthat were widely used in China were analyzed by AFLP fingerprinting. 12 primerpairs were screened, In order to simplify the procedure and cut down the cost inseed identification. the least number of primer pairs for practical seed identifi-cation should be seleeled. In this study. 3 primer pairs were selected. They
文摘The effect of La(NO3)(3) on natural or artificial aged rice seeds vigor was studied. The results show that the germination rate, germination index and vigor index of aged rice seed increase. Activities of superoxide dismutase, catalase and peroxidase are enhanced. . O-2(-) and malond ialdehyde contents decrease in germinating stage of aged rice seed, and cell membrane permeability of aged rice seeds reduces by treating with La(NO3)(3). The vigor increase of rice natural aged seed is greater than that of artificial aged rice seeds by treating with La(NO3)(3).
文摘The relation between seed viability and waterstatus in seed was studied.The experimentwas carried out at Zhongshan University.Seeds of hybrid rice Shanyou 63 were collectedfrom Guangdong Academy of Agriculture Sci-ences in 1993 and then stored for one year inopen air or with silica gel.Before and afterstorage,the relative content of free water andbound water in seeds were measured with
