Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we e...Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we employed two recombinant inbred line(RIL)populations with the common resistant parental line CML304 to identify FER-resistance loci.Initial QTL analysis identified 23 FER-resistance QTL,each explaining 5.21%-30.51%of the total phenotypic variation.Notably,one major QTL,qRfv2,on chromosome 2 was repeatedly detected,accounting for 11.92%-30.51%of the total phenotypic variation.qRfv2 was fine mapped to an interval of 1.01 Mb,flanked by the markers IDP8 and IDP10.qRfv2 is a semidominant resistance gene that could reduce the disease severity index(DSI)by 12.4%-20%,suggesting its potential for enhancing FER resistance in maize.Transcriptome analysis showed that 22 of the 28 annotated functional genes in the qRfv2 region displayed differential expression between parental lines in response to FER.One of the candidate genes,ZmLOX6,was validated to presumably provide a positive effect on FER resistance.Our study provides a basis for the potential cloning and application of FER resistance genes in maize breeding.展开更多
The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome edit...The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent selection.For HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive behaviors.Leveraging marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid identification.We show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCHEL morphogenetic factors.Finally,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk testers.The strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops.展开更多
Zero tillage with residues retention and optimizing nitrogen fertilization are important strategies to improve soil quality and wheat (Triticum aestivum L.) yield in rice (Oryza sativa L.)-wheat system. Field expe...Zero tillage with residues retention and optimizing nitrogen fertilization are important strategies to improve soil quality and wheat (Triticum aestivum L.) yield in rice (Oryza sativa L.)-wheat system. Field experiments were conducted on silty clay soil (Hyperthermic, and Typic Torrilfuvents) in D. I. Khan, Pakistan, to explore the impact of six tillage methods (zero tillage straw retained (ZTsr), ZT straw burnt (ZTsb), reduced tillage straw incorporated (RTsi, including tiller and rotavator), RT straw burnt (RTsb), conventional tillage straw incorporated (CTsi, including disc plow, tiller, rotavator, and leveling operations), CT straw burnt (CTsb)) and ifve nitrogen rates, i.e., 0, 100, 150, 200, and 250 kg ha-1 on wheat yield. Mean values for N revealed that spikes m-2, grains/spike, 1 000-grain weight (g), and grain yield (kg ha-1) were signiifcantly higher at 200 kg N ha-1 in both the years as well as mean over years than all other treatments. Mean values for tillage revealed that ZTsr produced highest number of spikes m-2 among tillage methods. However, grains/spike, 1 000-grain weight, and grain yield were higher in tillage methods with either straw retained/incorporated than tillage methods with straw burnt. Interaction effects were signiifcant in year 1 and in mean over years regarding spikes m-2, 1 000-grain weight, total soil organic matter (SOM), and total soil N (TSN). ZTsr produced the most spikes m-2 and 1 000-grain weight at 200 kg N ha-1. ZTsr also produced higher SOM and TSN at 200-250 kg N ha-1 at the end of 2 yr cropping. Thus ZTsr with 200 kg N ha-1 may be an optimum and sustainable approach to enhance wheat yield and soil quality in rice-wheat system.展开更多
A ifeld experiment was conducted to study the impact of tillage, crop residue management and nitrogen (N) splitting on spring wheat (Triticum aestivum L.) yield over 2 yr (2010-2012) in a rice (Oryza sativa L....A ifeld experiment was conducted to study the impact of tillage, crop residue management and nitrogen (N) splitting on spring wheat (Triticum aestivum L.) yield over 2 yr (2010-2012) in a rice (Oryza sativa L.)-wheat system in northwestern Pakistan. The experiment was conducted as split plot arranged in randomized complete blocks design with three replications. Treatments comprised six tillage and residue managements:zero tillage straw retained (ZTsr), zero tillage straw burnt (ZTsb), reduced tillage straw incorporated (RTsi), reduced tillage straw burnt (RTsb), conventional tillage straw incorporated (CTsi), and conventional tillage straw burnt (CTsb) as main plots and N (200 kg ha-1) was applied as split form viz., control (no nitrogen&no splitting, N0S0);2 splits of total N, half at sowing and half at the 1st irrigation (i.e., 20 d after sowing (DAS)) (NS1);3 splits of total N, 1/3 at sowing, 1/3 at the 1st irrigation, and 1/3 at the 2nd irrigation (NS2);4 splits of total N, 1/4 at sowing, 1/4 at the 1st irrigation, 1/4 at the 2nd irrigation (45 DAS), and 1/4 at the 3rd irrigation (70 DAS) (NS3);and 4 splits of total N, 1/4 at the 1st irrigation, 1/4 at the 2nd irrigation, 1/4 at the 3rd irrigation, and 1/4 at the 4th irrigation (95DAS) (NS4) as sub plots. The results showed that the most pikes m-2, grains/spike, 1 000-grain weight, grain yield, and N use efifciency (NUE) were obtained at zero tillage, straw retained and 4 splits application of total N (i.e., at sowing 20, 45 and 70 d after sowing). The results indicated that ZTsr with application of 200 kg N ha-1 in 4 equal splits viz. at sowing 20, 45 and 70 d after sowing is an appropriate strategy that enhanced wheat yield (7 436-7 634 kg ha-1) and N efifciency (28.6-29.5 kg kg-1) in rice-wheat system.展开更多
Translational regulation,especially tissue-or cell type-specific gene regulation,plays essential roles in plant growth and development.Thermo-sensitive genic male sterile(TGMS)lines have been widely used for hybrid br...Translational regulation,especially tissue-or cell type-specific gene regulation,plays essential roles in plant growth and development.Thermo-sensitive genic male sterile(TGMS)lines have been widely used for hybrid breeding in rice(Oryza sativa).However,little is known about translational regulation during reproductive stage in TGMS rice.Here,we use translating ribosome affinity purification(TRAP)combined with RNA sequencing to investigate the reproductive tissue-specific translatome of TGMS rice expressing FLAG-tagged ribosomal protein L18(RPL18)from the germline-specific promoter MEIOSIS ARRESTED AT LEPTOTENE1(MEL1).Differentially expressed genes at the transcriptional and translational levels are enriched in pollen and anther-related formation and development processes.These contain a number of genes reported to be involved in tapetum programmed cell death(PCD)and lipid metabolism during pollen development and anther dehiscence in rice,including several encoding transcription factors and key enzymes,as well as several long non-coding RNAs(lnc RNAs)that potentially affect tapetum and pollenrelated genes in male sterility.This study represents the comprehensive reproductive tissue-specific characterization of the translatome in TGMS rice.These results contribute to our understanding of the molecular basis of sterility in TGMS rice and will facilitate further genetic manipulation of TGMS rice in two-line breeding systems.展开更多
An experiment was carried out at the Agroforestry and Environment Research Farm, Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh, during April, 2014 to January 2015. The experiment was la...An experiment was carried out at the Agroforestry and Environment Research Farm, Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh, during April, 2014 to January 2015. The experiment was laid out in two factors Randomized Complete Block Design (RCBD) with three replications. Among the two factors, one factor like A was two production systems: S1 = Mango + Turmeric and S2 = Turmeric (sole crop);another factor like B was three turmeric variety: V1 = BARI Holud-1, V2 = BARI Holud-2 and V3 = BARI Holud-3. So, the treatment combinations were: S1V1 = Mango + BARI Holud-1, S1V2 = Mango + BARI Holud-2, S1V3 = Mango + BARI Holud-3, S2V1 = sole cropping of BARI Holud-1, S2V2 = sole cropping of BARI Holud-2 and S2V3 = sole cropping of BARI Holud-3. The result of the experiment revealed that interaction effect of production systems and variety was found significant on plant height, number of leaf per plant, length of leaf blade, breadth of leaf blade, number of finger per rhizome, fresh and dry yield per hectare. The higher fresh yield of turmeric (34.75 t/ha) and dry yield (6.10 t/ha) was found from S1V1 treatment (Mango + BARI Holud-1). Whereas the lowest fresh yield (33.41 t/ha) and dry yield (4.93 t/ha) was found from S2V2 treatment (sole cropping of BARI Holud-2). However, the suitability of the cultivation of different turmeric variety under mango based agroforestry systems may be ranked as S1V1 > S2V1 > S1V3 > S2V3 > S1V2 > S2V2. Finally it may be concluded that, BARI Holud-1 would be the best variety to be grown under mango based agroforestry.展开更多
The genetic diversity of 50 parents or improved lines of two-line medium Indica hybrid rice were analyzed based on 48 pairs of SSR markers. The results showed that the clustering results were highly accordant with the...The genetic diversity of 50 parents or improved lines of two-line medium Indica hybrid rice were analyzed based on 48 pairs of SSR markers. The results showed that the clustering results were highly accordant with the parental pedigree information of the tested materials. The male sterile lines and the restoring lines were clustered into 2 distinct groups (Ⅰ and Ⅱ), respectively. There were no significant difference in intra-group average genetic distances (GD) between the 2 groups. Most of the male sterile lines from Hunan Longping High-tech Seed Science Research Institute Co., Ltd. were grouped into a single subgroup (Ⅰ-4) under the male sterile group with the largest average GD compared with the rest male sterile subgroups. Huazhan derived lines and Guangzhou inbred lines were founded to be independent of 9311 and its derivatives or closely-related lines. Meanwhile, they have obviously been differentiated into 2 subgroups (Ⅱ-2 and Ⅱ-3). The lines derived from Huazhan (or genetic closely related lines) showed a genetic homogenization phenomenon. Therefore, the Huazhan-derived lines should be further improved by the utilization of germplasms with good quality, high resistance and wide adaptability from Southern China to widen the GD between Huazhan derived lines and the male sterile subgroup developed by Hunan Longping High-tech Seed Science Research Institute Co., Ltd., so as to further promote the heterosis level between the groups.展开更多
Horsegram is an important and unexploited tropic and sub-tropic legume crop grown mostly in dry land agriculture. The study involving 23 cultivars of horsegram (Dolichos uniflorus) was conducted at the Seed Research...Horsegram is an important and unexploited tropic and sub-tropic legume crop grown mostly in dry land agriculture. The study involving 23 cultivars of horsegram (Dolichos uniflorus) was conducted at the Seed Research & Technology Centre in Rajendranagar, Hyderabad, India during the early spring seasons of 2008 and 2009 to assess the nature and magnitude of variability in the existing species and also to identify diverse parents for use in further breeding programmes. The results indicated significant differences among the 23 cultivars for all characters studied, indicating the presence of sufficient genetic variation. High variability and heritability coupled with high genetic advance were reported for seed yield per plant and pod hulm per plant, indicating additive gene action and a possible scope for the improvement of these characters. Mahalanobis D2 statistics grouped all the 23 cultivars of horsegram into six ,clusters. The maximum inter cluster distance (62.39) was noticed between cluster IV (HG 50) and cluster V (HG 11). The maximum Jntra cluster distance ranged from 0 (clusters III, IV, V and VI) to 15.17 (cluster I), indicating that the genotypes in these clusters were relatively more diverse than the genotypes within other clusters. Seed yield per plant contributed the maximum (33.20%) to the genetic divergence.展开更多
Dormancy is undesirable character for the peanut seed(Arachis hypogeae).KK 84-7 and KK 6 varieties are characterized to the Virginia type and its dormant period has been one to two months after harvest.The recommendat...Dormancy is undesirable character for the peanut seed(Arachis hypogeae).KK 84-7 and KK 6 varieties are characterized to the Virginia type and its dormant period has been one to two months after harvest.The recommendation for breaking peanut seed dormancy by the International Seed Testing Association(ISTA)rules is preheat at 40°C up to 168 h.The total germination test is 17 d,if breaking dormant seed is required.Effect of ethephon on peanut seed dormancy release was studied in this experiment to reduce the analysis time compared to preheat method.Both varieties of peanut seeds were directly mixed with 0.96%ethephon and preheated at 40°C for 168 h.Standard germinations were conducted for all treated and untreated seeds.Ethephon was the most beneficial to release dormant seed at fresh harvest that achieved 86%and 84%normal seedlings for KK 84-7 and KK 6,respectively.The normal seedlings of preheat treatment showed 75%for KK 84-7,and 66%for KK 6.Only 6%normal seedlings were observed in untreated seeds of KK 84-7 and 56%of KK 6.After storage at 20°C for 28 d,KK 84-7 had over 90%normal seedlings with both ethephon and preheat methods,but only 42%germination was observed in untreated seeds.In KK 6,the highest germination by 90%was found in ethephon,followed by untreated and preheated seeds that were 87%and 83%,respectively.The paired t test of normal seedlings between ethephon and preheat treatments demonstrated that the greater average germination was found in ethephon method for both varieties.This research suggests that ethephon is the advantageous method for breaking peanut seed dormancy.The germination test duration is more rapid,only 10 d,since preheat for 168 h is not necessary.展开更多
Ultrafine bubbles and low doses of gamma irradiation had a positive effect on seed germination.This research tested the effectiveness of ultrafine bubbles(UFB)water and gamma irradiation for improving the viability an...Ultrafine bubbles and low doses of gamma irradiation had a positive effect on seed germination.This research tested the effectiveness of ultrafine bubbles(UFB)water and gamma irradiation for improving the viability and vigor of Albizia chinensis(Osbeck)Merr.seeds that had been stored for four years.A completely randomized two-factor experiment,i.e.,UFB water and gamma irradiation treatments,were used to determine the best seed treatment.The UFB water treatment had a significant effect on all seed germination parameters;the gamma irradiation treatment did not have a significant effect on improving the viability and vigor of the seeds,with a very low initial germination(11.7%).Soaking the seeds in UFB water for 30 min gave the best germination(51.3%).These improvements also occurred in other germination parameters such as germination rate,germination value,radicle length and vigor index.The UFB water treatment has the potential to improve the germination of seeds with low physiological qualities.展开更多
Fresh-cut lettuce is popular,but highly perishable product.Genetic studies of two bi-parental populations derived from crossing parents with rapid and slow rates of deterioration showed that the deterioration rate is ...Fresh-cut lettuce is popular,but highly perishable product.Genetic studies of two bi-parental populations derived from crossing parents with rapid and slow rates of deterioration showed that the deterioration rate is a heritable trait(broad spectrum heritability,H2 of 0.56–0.87).The major genetic determinant of the deterioration rate in both populations was the quantitative trait locus(QTL),qSL4,located on linkage group 4.This QTL explained 40–74%of the total phenotypic variation of the trait in the two populations.Saturating the qSL4 region with single-nucleotide(SNP)markers allowed detection of six haplotypes in a set of 16 lettuce accessions with different rates of deterioration.Three of the haplotypes were always associated with very rapid rates of deterioration,while the other three haplotypes were associated with slow rates of deterioration.Two SNPs located 53 bp apart were sufficient to separate the 16 accessions into two groups with different rates of deterioration.The accuracy of markers-trait association was subsequently tested on 350 plants from seven F2 families that originated from crossing parents with different rates of deterioration.The H2 of deterioration rate in these seven families ranged from 0.64 to 0.90.The SNP-based analysis accurately identified individuals with rapid,intermediate,and slow rates of deterioration in each family.Intermediate rate of deterioration was found in individuals having heterozygous alleles at qSL4,indicating an additive effect of the alleles.The assay can be used for fast,accurate,and reliable identification of deterioration rate after processing for salad.展开更多
Pre-harvest desiccation in order to minimize the time of exposure to abiotic factors after physiological maturity is a practice used in the production of quality seeds. The aim of this work was to evaluate the physica...Pre-harvest desiccation in order to minimize the time of exposure to abiotic factors after physiological maturity is a practice used in the production of quality seeds. The aim of this work was to evaluate the physical, physiological and sanitary quality of wheat seeds from plants that received non-selective herbicide application at pre-harvest. For this, the treatments were applied on pre-harvest culture. A completely randomized design was applied. We use the herbicides (glufosinate-ammonium, glyphosate and paraquat), phenological stages of herbicide application (Z-83, Z-85, Z-87, Z-92) and additional treatment (without application). The routine tests that express the physical, physiological and sanitary integrity of seeds were evaluated. For herbicide treatments, there was an 8% and 26% reduction in germination under laboratory conditions for BRS Parrudo and Sinuelo, respectively. Soil emergence was 14% higher for the control treatment, not statistically different for the Z-87 and Z-92 stages and also for the herbicides glufosinate-ammonium and glyphosate for both cultivars. The application of non-selective herbicides on wheat pre-harvest impairs the physical and physiological quality and promotes faster deterioration. Vigor is reduced under stress conditions by cold test and accelerated aging. There is no influence on seed sanity.展开更多
Efficient genotype-independent transformation and genome editing are highly desirable for plant biotechnology research and product development efforts.We have developed a novel approach to enable fast,high-throughput,...Efficient genotype-independent transformation and genome editing are highly desirable for plant biotechnology research and product development efforts.We have developed a novel approach to enable fast,high-throughput,and genotype-flexible Agrobacterium-mediated transformation using the important crop soybean as a test system.This new method is called GiFT(genotype-independent fast transformation)and involves only a few simple steps.The method uses germinated seeds as explants,and DNA delivery is achieved through Agrobacterium infection of wounded explants as in conventional in vitro-based methods.Following infection,the wounded explants are incubated in liquid medium with a sublethal level of selection and then transplanted directly into soil.The transplanted seedlings are then selected with herbicide spray for 3 weeks.The time required from initiation to fully established healthy T0 transgenic events is about 35 days.The GiFT method requires minimal in vitro manipulation or use of tissue culture media.Because the regeneration occurs in planta,the GiFT method is highly flexible with respect to genotype,which we demonstrate via successful transformation of elite germplasms from diverse genetic backgrounds.We also show that the soybean GiFT method can be applied to both conventional binary vectors and CRISPR-Cas12a vectors for genome editing applications.Analyses of T1 progeny demonstrate that the events have a high inheritance rate and can be used for genome engineering applications.By minimizing the need for tissue culture,the novel approach described here significantly improves operational efficiency while greatly reducing personnel and supply costs.It is the first industry-scale transformation method to utilize in planta selection in a major field crop.展开更多
Ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)is a pivotal enzyme that mediates the fixation of CO_(2).As the most abundant protein on earth,Rubisco has a significant impact on global carbon,water,and nitrog...Ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)is a pivotal enzyme that mediates the fixation of CO_(2).As the most abundant protein on earth,Rubisco has a significant impact on global carbon,water,and nitrogen cycles.However,the significantly low carboxylation activity and competing oxygenase activity of Rubisco greatly impede high carbon fixation efficiency.This review first summarizes the current efforts in directly or indirectly modifying plant Rubisco,which has been challenging due to its high conservation and limitations in chloroplast transformation techniques.However,recent advancements in understanding Rubisco biogenesis with the assistance of chaperones have enabled successful heterologous expression of all Rubisco forms,including plant Rubisco,in microorganisms.This breakthrough facilitates the acquisition and evaluation of modified proteins,streamlining the measurement of their activity.Moreover,the establishment of a screening system in E.coli opens up possibilities for obtaining high-performance mutant enzymes through directed evolution.Finally,this review emphasizes the utilization of Rubisco in microorganisms,not only expanding their carbon-fixing capabilities but also holding significant potential for enhancing biotransformation processes.展开更多
Breeding semi-dwarf varieties to improve lodging resistance has been proven to be enormously successful in increasing grain yield since the advent of the "green revolution." However, the breeding of the majority of ...Breeding semi-dwarf varieties to improve lodging resistance has been proven to be enormously successful in increasing grain yield since the advent of the "green revolution." However, the breeding of the majority of semi-dwarf rice varieties in Asia has been dependent mainly on genetic introduction of the mutant alleles of SD1, which encodes a gibberellin (GA) 20-oxidase, OsGA20ox2, for catalyzing GA biosynthesis. Here, we report a new rice lodging-resistance gene, Shortened Basal lnternodes (SBI), which encodes a gibberellin 2- oxidase and specifically controls the elongation of culm basal internodes through deactivating GA activity. SBI is predominantly expressed in culm basal internodes. Genetic analyses indicate that SBI is a semidominant gene affecting rice height and lodging resistance. SBI allelic variants display different activities and are associated with the height of rice varieties. Breeding with higher activity of the SBI allele generates new rice varieties with improved lodging resistance and increased yield. The discovery of the SB! provides a desirable gene resource for producing semi-dwarf rice phenotypes and offers an effective strategy for breeding rice varieties with enhanced lodging resistance and high yield.展开更多
Dear Editor,Many Cas9-derived base editors have been developed for precise C-to-T and A-to-G base editing in plants(Molla et al.,2021).They are typically based on a SpCas9 nickase or its engineered variants with alter...Dear Editor,Many Cas9-derived base editors have been developed for precise C-to-T and A-to-G base editing in plants(Molla et al.,2021).They are typically based on a SpCas9 nickase or its engineered variants with altered protospacer adjacent motif(PAM)requirements(Molla et al.,2021).CRISPR-Cas12a enables highly efficient multiplexed genome editing in plants,and its T-rich PAM preference complements the G-rich PAM requirement of SpCas9 in genome targeting(Zhang et al.,2019,2021).Because of the lack of an efficient Cas12a nickase,it has been challenging to develop efficient Cas12a base editors.Nevertheless,Cas12a cytosine base editors(CBEs)and adenine base editors(ABEs)have been developed in mammalian cells(Li et al.,2018;Kleinstiver et al.,2019)with low DNA damage(Wang et al.,2020)because deactivated Cas12a(dCas12a)was used.However,efficient dCas12a base editors are yet to be developed in plants.展开更多
The Oronogo-Duenweg mining belt is a designated United States Environmental Protection Agency Superfund site due to lead-contaminated soil and groundwater by former mining and smelting operations.Sites that have under...The Oronogo-Duenweg mining belt is a designated United States Environmental Protection Agency Superfund site due to lead-contaminated soil and groundwater by former mining and smelting operations.Sites that have undergone remediation-in which the O,A,and B horizons have been removed alongside the lead contamination-have an exposed C horizon and are incalcitrant to revegetation efforts.Soils also continue to contain quantifiable Cd and Zn concentrations.To improve soil conditions and encourage successful site revegetation,our study employed three biochars,sourced from different feedstocks(poultry litter,beef cattle manure,and lodgepole pine),at two rates of application(2.5%,and 5%),coupled with compost(0%,2.5%and 5%application rates).Two plant species-switchgrass(Panicum virgatum)and buffalograss(Bouteloua dactyloides)-were grown in the amended soils.Amendment of soils with poultry litter biochar applied at 5%resulted in the greatest reduction of soil bioavailable Cd and Zn.Above-ground biomass yields were greatest with beef cattle manure biochar applied at 2.5%with 5%compost,or with 5%biochar at 2.5%and 5%compost rates.Maximal microbial biomass was achieved with 5%poultry litter biochar and 5%compost,and microbial communities in soils amended with poultry litter biochar distinctly clustered away from all other soil treatments.Additionally,poultry litter biochar amended soils had the highest enzyme activity rates forβ-glucosidase,N-acetyl-β-D-glucosaminidase,and esterase.These results suggest that soil reclamation using biochar and compost can improve mine-impacted soil biogeophysical characteristics,and potentially improve future remediation efforts.展开更多
基金financially funded by the National Natural Science Foundation of China(U2004205)the China Agricultural University-Syngenta Project.
文摘Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we employed two recombinant inbred line(RIL)populations with the common resistant parental line CML304 to identify FER-resistance loci.Initial QTL analysis identified 23 FER-resistance QTL,each explaining 5.21%-30.51%of the total phenotypic variation.Notably,one major QTL,qRfv2,on chromosome 2 was repeatedly detected,accounting for 11.92%-30.51%of the total phenotypic variation.qRfv2 was fine mapped to an interval of 1.01 Mb,flanked by the markers IDP8 and IDP10.qRfv2 is a semidominant resistance gene that could reduce the disease severity index(DSI)by 12.4%-20%,suggesting its potential for enhancing FER resistance in maize.Transcriptome analysis showed that 22 of the 28 annotated functional genes in the qRfv2 region displayed differential expression between parental lines in response to FER.One of the candidate genes,ZmLOX6,was validated to presumably provide a positive effect on FER resistance.Our study provides a basis for the potential cloning and application of FER resistance genes in maize breeding.
文摘The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent selection.For HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive behaviors.Leveraging marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid identification.We show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCHEL morphogenetic factors.Finally,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk testers.The strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops.
文摘Zero tillage with residues retention and optimizing nitrogen fertilization are important strategies to improve soil quality and wheat (Triticum aestivum L.) yield in rice (Oryza sativa L.)-wheat system. Field experiments were conducted on silty clay soil (Hyperthermic, and Typic Torrilfuvents) in D. I. Khan, Pakistan, to explore the impact of six tillage methods (zero tillage straw retained (ZTsr), ZT straw burnt (ZTsb), reduced tillage straw incorporated (RTsi, including tiller and rotavator), RT straw burnt (RTsb), conventional tillage straw incorporated (CTsi, including disc plow, tiller, rotavator, and leveling operations), CT straw burnt (CTsb)) and ifve nitrogen rates, i.e., 0, 100, 150, 200, and 250 kg ha-1 on wheat yield. Mean values for N revealed that spikes m-2, grains/spike, 1 000-grain weight (g), and grain yield (kg ha-1) were signiifcantly higher at 200 kg N ha-1 in both the years as well as mean over years than all other treatments. Mean values for tillage revealed that ZTsr produced highest number of spikes m-2 among tillage methods. However, grains/spike, 1 000-grain weight, and grain yield were higher in tillage methods with either straw retained/incorporated than tillage methods with straw burnt. Interaction effects were signiifcant in year 1 and in mean over years regarding spikes m-2, 1 000-grain weight, total soil organic matter (SOM), and total soil N (TSN). ZTsr produced the most spikes m-2 and 1 000-grain weight at 200 kg N ha-1. ZTsr also produced higher SOM and TSN at 200-250 kg N ha-1 at the end of 2 yr cropping. Thus ZTsr with 200 kg N ha-1 may be an optimum and sustainable approach to enhance wheat yield and soil quality in rice-wheat system.
文摘A ifeld experiment was conducted to study the impact of tillage, crop residue management and nitrogen (N) splitting on spring wheat (Triticum aestivum L.) yield over 2 yr (2010-2012) in a rice (Oryza sativa L.)-wheat system in northwestern Pakistan. The experiment was conducted as split plot arranged in randomized complete blocks design with three replications. Treatments comprised six tillage and residue managements:zero tillage straw retained (ZTsr), zero tillage straw burnt (ZTsb), reduced tillage straw incorporated (RTsi), reduced tillage straw burnt (RTsb), conventional tillage straw incorporated (CTsi), and conventional tillage straw burnt (CTsb) as main plots and N (200 kg ha-1) was applied as split form viz., control (no nitrogen&no splitting, N0S0);2 splits of total N, half at sowing and half at the 1st irrigation (i.e., 20 d after sowing (DAS)) (NS1);3 splits of total N, 1/3 at sowing, 1/3 at the 1st irrigation, and 1/3 at the 2nd irrigation (NS2);4 splits of total N, 1/4 at sowing, 1/4 at the 1st irrigation, 1/4 at the 2nd irrigation (45 DAS), and 1/4 at the 3rd irrigation (70 DAS) (NS3);and 4 splits of total N, 1/4 at the 1st irrigation, 1/4 at the 2nd irrigation, 1/4 at the 3rd irrigation, and 1/4 at the 4th irrigation (95DAS) (NS4) as sub plots. The results showed that the most pikes m-2, grains/spike, 1 000-grain weight, grain yield, and N use efifciency (NUE) were obtained at zero tillage, straw retained and 4 splits application of total N (i.e., at sowing 20, 45 and 70 d after sowing). The results indicated that ZTsr with application of 200 kg N ha-1 in 4 equal splits viz. at sowing 20, 45 and 70 d after sowing is an appropriate strategy that enhanced wheat yield (7 436-7 634 kg ha-1) and N efifciency (28.6-29.5 kg kg-1) in rice-wheat system.
基金supported by grants from the National Key Research and Development Program of China (2020YFA0509900)the National Natural Science Foundation of China (31788103, 32171284, 31991184 and 31701096)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences (XDA24010302)the State Key Laboratory of Plant Genomics, China
文摘Translational regulation,especially tissue-or cell type-specific gene regulation,plays essential roles in plant growth and development.Thermo-sensitive genic male sterile(TGMS)lines have been widely used for hybrid breeding in rice(Oryza sativa).However,little is known about translational regulation during reproductive stage in TGMS rice.Here,we use translating ribosome affinity purification(TRAP)combined with RNA sequencing to investigate the reproductive tissue-specific translatome of TGMS rice expressing FLAG-tagged ribosomal protein L18(RPL18)from the germline-specific promoter MEIOSIS ARRESTED AT LEPTOTENE1(MEL1).Differentially expressed genes at the transcriptional and translational levels are enriched in pollen and anther-related formation and development processes.These contain a number of genes reported to be involved in tapetum programmed cell death(PCD)and lipid metabolism during pollen development and anther dehiscence in rice,including several encoding transcription factors and key enzymes,as well as several long non-coding RNAs(lnc RNAs)that potentially affect tapetum and pollenrelated genes in male sterility.This study represents the comprehensive reproductive tissue-specific characterization of the translatome in TGMS rice.These results contribute to our understanding of the molecular basis of sterility in TGMS rice and will facilitate further genetic manipulation of TGMS rice in two-line breeding systems.
文摘An experiment was carried out at the Agroforestry and Environment Research Farm, Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh, during April, 2014 to January 2015. The experiment was laid out in two factors Randomized Complete Block Design (RCBD) with three replications. Among the two factors, one factor like A was two production systems: S1 = Mango + Turmeric and S2 = Turmeric (sole crop);another factor like B was three turmeric variety: V1 = BARI Holud-1, V2 = BARI Holud-2 and V3 = BARI Holud-3. So, the treatment combinations were: S1V1 = Mango + BARI Holud-1, S1V2 = Mango + BARI Holud-2, S1V3 = Mango + BARI Holud-3, S2V1 = sole cropping of BARI Holud-1, S2V2 = sole cropping of BARI Holud-2 and S2V3 = sole cropping of BARI Holud-3. The result of the experiment revealed that interaction effect of production systems and variety was found significant on plant height, number of leaf per plant, length of leaf blade, breadth of leaf blade, number of finger per rhizome, fresh and dry yield per hectare. The higher fresh yield of turmeric (34.75 t/ha) and dry yield (6.10 t/ha) was found from S1V1 treatment (Mango + BARI Holud-1). Whereas the lowest fresh yield (33.41 t/ha) and dry yield (4.93 t/ha) was found from S2V2 treatment (sole cropping of BARI Holud-2). However, the suitability of the cultivation of different turmeric variety under mango based agroforestry systems may be ranked as S1V1 > S2V1 > S1V3 > S2V3 > S1V2 > S2V2. Finally it may be concluded that, BARI Holud-1 would be the best variety to be grown under mango based agroforestry.
基金Supported by Open Project of State Key Laboratory of Hybrid Rice(2015KF05)China Postdoctoral Science Foundation(2015M572261)National Key Research and Development Program(2016YFD0101801)~~
文摘The genetic diversity of 50 parents or improved lines of two-line medium Indica hybrid rice were analyzed based on 48 pairs of SSR markers. The results showed that the clustering results were highly accordant with the parental pedigree information of the tested materials. The male sterile lines and the restoring lines were clustered into 2 distinct groups (Ⅰ and Ⅱ), respectively. There were no significant difference in intra-group average genetic distances (GD) between the 2 groups. Most of the male sterile lines from Hunan Longping High-tech Seed Science Research Institute Co., Ltd. were grouped into a single subgroup (Ⅰ-4) under the male sterile group with the largest average GD compared with the rest male sterile subgroups. Huazhan derived lines and Guangzhou inbred lines were founded to be independent of 9311 and its derivatives or closely-related lines. Meanwhile, they have obviously been differentiated into 2 subgroups (Ⅱ-2 and Ⅱ-3). The lines derived from Huazhan (or genetic closely related lines) showed a genetic homogenization phenomenon. Therefore, the Huazhan-derived lines should be further improved by the utilization of germplasms with good quality, high resistance and wide adaptability from Southern China to widen the GD between Huazhan derived lines and the male sterile subgroup developed by Hunan Longping High-tech Seed Science Research Institute Co., Ltd., so as to further promote the heterosis level between the groups.
文摘Horsegram is an important and unexploited tropic and sub-tropic legume crop grown mostly in dry land agriculture. The study involving 23 cultivars of horsegram (Dolichos uniflorus) was conducted at the Seed Research & Technology Centre in Rajendranagar, Hyderabad, India during the early spring seasons of 2008 and 2009 to assess the nature and magnitude of variability in the existing species and also to identify diverse parents for use in further breeding programmes. The results indicated significant differences among the 23 cultivars for all characters studied, indicating the presence of sufficient genetic variation. High variability and heritability coupled with high genetic advance were reported for seed yield per plant and pod hulm per plant, indicating additive gene action and a possible scope for the improvement of these characters. Mahalanobis D2 statistics grouped all the 23 cultivars of horsegram into six ,clusters. The maximum inter cluster distance (62.39) was noticed between cluster IV (HG 50) and cluster V (HG 11). The maximum Jntra cluster distance ranged from 0 (clusters III, IV, V and VI) to 15.17 (cluster I), indicating that the genotypes in these clusters were relatively more diverse than the genotypes within other clusters. Seed yield per plant contributed the maximum (33.20%) to the genetic divergence.
文摘Dormancy is undesirable character for the peanut seed(Arachis hypogeae).KK 84-7 and KK 6 varieties are characterized to the Virginia type and its dormant period has been one to two months after harvest.The recommendation for breaking peanut seed dormancy by the International Seed Testing Association(ISTA)rules is preheat at 40°C up to 168 h.The total germination test is 17 d,if breaking dormant seed is required.Effect of ethephon on peanut seed dormancy release was studied in this experiment to reduce the analysis time compared to preheat method.Both varieties of peanut seeds were directly mixed with 0.96%ethephon and preheated at 40°C for 168 h.Standard germinations were conducted for all treated and untreated seeds.Ethephon was the most beneficial to release dormant seed at fresh harvest that achieved 86%and 84%normal seedlings for KK 84-7 and KK 6,respectively.The normal seedlings of preheat treatment showed 75%for KK 84-7,and 66%for KK 6.Only 6%normal seedlings were observed in untreated seeds of KK 84-7 and 56%of KK 6.After storage at 20°C for 28 d,KK 84-7 had over 90%normal seedlings with both ethephon and preheat methods,but only 42%germination was observed in untreated seeds.In KK 6,the highest germination by 90%was found in ethephon,followed by untreated and preheated seeds that were 87%and 83%,respectively.The paired t test of normal seedlings between ethephon and preheat treatments demonstrated that the greater average germination was found in ethephon method for both varieties.This research suggests that ethephon is the advantageous method for breaking peanut seed dormancy.The germination test duration is more rapid,only 10 d,since preheat for 168 h is not necessary.
基金supported by the Forest Tree Seed Technology Research and Development Center,Ministry of Environment and Forestry,Republic of Indonesia
文摘Ultrafine bubbles and low doses of gamma irradiation had a positive effect on seed germination.This research tested the effectiveness of ultrafine bubbles(UFB)water and gamma irradiation for improving the viability and vigor of Albizia chinensis(Osbeck)Merr.seeds that had been stored for four years.A completely randomized two-factor experiment,i.e.,UFB water and gamma irradiation treatments,were used to determine the best seed treatment.The UFB water treatment had a significant effect on all seed germination parameters;the gamma irradiation treatment did not have a significant effect on improving the viability and vigor of the seeds,with a very low initial germination(11.7%).Soaking the seeds in UFB water for 30 min gave the best germination(51.3%).These improvements also occurred in other germination parameters such as germination rate,germination value,radicle length and vigor index.The UFB water treatment has the potential to improve the germination of seeds with low physiological qualities.
基金This work was partly supported by the California Leafy Greens Research Program and the United States Department of Agriculture,National Institute of Food and Agriculture,Specialty Crop Research Initiative program award#s 2010-51181-21631 and 2015-51181-24283.
文摘Fresh-cut lettuce is popular,but highly perishable product.Genetic studies of two bi-parental populations derived from crossing parents with rapid and slow rates of deterioration showed that the deterioration rate is a heritable trait(broad spectrum heritability,H2 of 0.56–0.87).The major genetic determinant of the deterioration rate in both populations was the quantitative trait locus(QTL),qSL4,located on linkage group 4.This QTL explained 40–74%of the total phenotypic variation of the trait in the two populations.Saturating the qSL4 region with single-nucleotide(SNP)markers allowed detection of six haplotypes in a set of 16 lettuce accessions with different rates of deterioration.Three of the haplotypes were always associated with very rapid rates of deterioration,while the other three haplotypes were associated with slow rates of deterioration.Two SNPs located 53 bp apart were sufficient to separate the 16 accessions into two groups with different rates of deterioration.The accuracy of markers-trait association was subsequently tested on 350 plants from seven F2 families that originated from crossing parents with different rates of deterioration.The H2 of deterioration rate in these seven families ranged from 0.64 to 0.90.The SNP-based analysis accurately identified individuals with rapid,intermediate,and slow rates of deterioration in each family.Intermediate rate of deterioration was found in individuals having heterozygous alleles at qSL4,indicating an additive effect of the alleles.The assay can be used for fast,accurate,and reliable identification of deterioration rate after processing for salad.
基金the Higher-Level Personnel Improvement Coordination(Capes-Brazil)for the scholarship provided,The National Council for Scientific and Technological Development(CNPq).
文摘Pre-harvest desiccation in order to minimize the time of exposure to abiotic factors after physiological maturity is a practice used in the production of quality seeds. The aim of this work was to evaluate the physical, physiological and sanitary quality of wheat seeds from plants that received non-selective herbicide application at pre-harvest. For this, the treatments were applied on pre-harvest culture. A completely randomized design was applied. We use the herbicides (glufosinate-ammonium, glyphosate and paraquat), phenological stages of herbicide application (Z-83, Z-85, Z-87, Z-92) and additional treatment (without application). The routine tests that express the physical, physiological and sanitary integrity of seeds were evaluated. For herbicide treatments, there was an 8% and 26% reduction in germination under laboratory conditions for BRS Parrudo and Sinuelo, respectively. Soil emergence was 14% higher for the control treatment, not statistically different for the Z-87 and Z-92 stages and also for the herbicides glufosinate-ammonium and glyphosate for both cultivars. The application of non-selective herbicides on wheat pre-harvest impairs the physical and physiological quality and promotes faster deterioration. Vigor is reduced under stress conditions by cold test and accelerated aging. There is no influence on seed sanity.
基金The information described in this article is covered by two Syngenta patent publications:WO20211108336 and WO2021108337.
文摘Efficient genotype-independent transformation and genome editing are highly desirable for plant biotechnology research and product development efforts.We have developed a novel approach to enable fast,high-throughput,and genotype-flexible Agrobacterium-mediated transformation using the important crop soybean as a test system.This new method is called GiFT(genotype-independent fast transformation)and involves only a few simple steps.The method uses germinated seeds as explants,and DNA delivery is achieved through Agrobacterium infection of wounded explants as in conventional in vitro-based methods.Following infection,the wounded explants are incubated in liquid medium with a sublethal level of selection and then transplanted directly into soil.The transplanted seedlings are then selected with herbicide spray for 3 weeks.The time required from initiation to fully established healthy T0 transgenic events is about 35 days.The GiFT method requires minimal in vitro manipulation or use of tissue culture media.Because the regeneration occurs in planta,the GiFT method is highly flexible with respect to genotype,which we demonstrate via successful transformation of elite germplasms from diverse genetic backgrounds.We also show that the soybean GiFT method can be applied to both conventional binary vectors and CRISPR-Cas12a vectors for genome editing applications.Analyses of T1 progeny demonstrate that the events have a high inheritance rate and can be used for genome engineering applications.By minimizing the need for tissue culture,the novel approach described here significantly improves operational efficiency while greatly reducing personnel and supply costs.It is the first industry-scale transformation method to utilize in planta selection in a major field crop.
基金supported by the National Key R&D Program of China(2021YFC2103500)the National Natural Science Foundation of China(32270057)the DNL Cooperation Fund,CAS(DNL202014).
文摘Ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)is a pivotal enzyme that mediates the fixation of CO_(2).As the most abundant protein on earth,Rubisco has a significant impact on global carbon,water,and nitrogen cycles.However,the significantly low carboxylation activity and competing oxygenase activity of Rubisco greatly impede high carbon fixation efficiency.This review first summarizes the current efforts in directly or indirectly modifying plant Rubisco,which has been challenging due to its high conservation and limitations in chloroplast transformation techniques.However,recent advancements in understanding Rubisco biogenesis with the assistance of chaperones have enabled successful heterologous expression of all Rubisco forms,including plant Rubisco,in microorganisms.This breakthrough facilitates the acquisition and evaluation of modified proteins,streamlining the measurement of their activity.Moreover,the establishment of a screening system in E.coli opens up possibilities for obtaining high-performance mutant enzymes through directed evolution.Finally,this review emphasizes the utilization of Rubisco in microorganisms,not only expanding their carbon-fixing capabilities but also holding significant potential for enhancing biotransformation processes.
基金This work was supported by the Chinese Academy of Sciences (CEMPS2016009 XDA08020203), the Ministry of Science and Technology of China (2013CB127002 2016YFD0102102), and the National Natural Science Foundation of China (31571635).
文摘Breeding semi-dwarf varieties to improve lodging resistance has been proven to be enormously successful in increasing grain yield since the advent of the "green revolution." However, the breeding of the majority of semi-dwarf rice varieties in Asia has been dependent mainly on genetic introduction of the mutant alleles of SD1, which encodes a gibberellin (GA) 20-oxidase, OsGA20ox2, for catalyzing GA biosynthesis. Here, we report a new rice lodging-resistance gene, Shortened Basal lnternodes (SBI), which encodes a gibberellin 2- oxidase and specifically controls the elongation of culm basal internodes through deactivating GA activity. SBI is predominantly expressed in culm basal internodes. Genetic analyses indicate that SBI is a semidominant gene affecting rice height and lodging resistance. SBI allelic variants display different activities and are associated with the height of rice varieties. Breeding with higher activity of the SBI allele generates new rice varieties with improved lodging resistance and increased yield. The discovery of the SB! provides a desirable gene resource for producing semi-dwarf rice phenotypes and offers an effective strategy for breeding rice varieties with enhanced lodging resistance and high yield.
基金Some linkers used in this study were disclosed in a Syngenta patent application(WO2021061507).No conflict of interest is declared.
文摘Dear Editor,Many Cas9-derived base editors have been developed for precise C-to-T and A-to-G base editing in plants(Molla et al.,2021).They are typically based on a SpCas9 nickase or its engineered variants with altered protospacer adjacent motif(PAM)requirements(Molla et al.,2021).CRISPR-Cas12a enables highly efficient multiplexed genome editing in plants,and its T-rich PAM preference complements the G-rich PAM requirement of SpCas9 in genome targeting(Zhang et al.,2019,2021).Because of the lack of an efficient Cas12a nickase,it has been challenging to develop efficient Cas12a base editors.Nevertheless,Cas12a cytosine base editors(CBEs)and adenine base editors(ABEs)have been developed in mammalian cells(Li et al.,2018;Kleinstiver et al.,2019)with low DNA damage(Wang et al.,2020)because deactivated Cas12a(dCas12a)was used.However,efficient dCas12a base editors are yet to be developed in plants.
基金The information in this document has been funded in part by the U.S.Environmental Protection Agency.
文摘The Oronogo-Duenweg mining belt is a designated United States Environmental Protection Agency Superfund site due to lead-contaminated soil and groundwater by former mining and smelting operations.Sites that have undergone remediation-in which the O,A,and B horizons have been removed alongside the lead contamination-have an exposed C horizon and are incalcitrant to revegetation efforts.Soils also continue to contain quantifiable Cd and Zn concentrations.To improve soil conditions and encourage successful site revegetation,our study employed three biochars,sourced from different feedstocks(poultry litter,beef cattle manure,and lodgepole pine),at two rates of application(2.5%,and 5%),coupled with compost(0%,2.5%and 5%application rates).Two plant species-switchgrass(Panicum virgatum)and buffalograss(Bouteloua dactyloides)-were grown in the amended soils.Amendment of soils with poultry litter biochar applied at 5%resulted in the greatest reduction of soil bioavailable Cd and Zn.Above-ground biomass yields were greatest with beef cattle manure biochar applied at 2.5%with 5%compost,or with 5%biochar at 2.5%and 5%compost rates.Maximal microbial biomass was achieved with 5%poultry litter biochar and 5%compost,and microbial communities in soils amended with poultry litter biochar distinctly clustered away from all other soil treatments.Additionally,poultry litter biochar amended soils had the highest enzyme activity rates forβ-glucosidase,N-acetyl-β-D-glucosaminidase,and esterase.These results suggest that soil reclamation using biochar and compost can improve mine-impacted soil biogeophysical characteristics,and potentially improve future remediation efforts.