The variation among Chinese genotypes of Brassica napus L. for seed tocopherols content and their analysis using gas chromatography has not been comprehensively reported till to date. In the present study, the tocophe...The variation among Chinese genotypes of Brassica napus L. for seed tocopherols content and their analysis using gas chromatography has not been comprehensively reported till to date. In the present study, the tocopherol contents of four Chinese genotypes of Brassica napus L., namely, Gaoyou 605, Zhejiang 619, Zheshuang 758, and Zheshuang 72, were evaluated using three modified sample preparation protocols (P1, P2, and P3) for tocopherol extraction. These methods were distinguished as follows. Protocol one (P1) included the evaporation of solvent after extraction without silylation. Protocol two (P2) followed the direct supernatant collection after overnight extraction without drying and silylation. Protocol three (P3) included trimethylsilylation with N,O-bis(trimethylsilyl) trifluoroacetamide. Genotypic comparison of tocopherol and its isoforms revealed that Gaoyou 605 was dominant over the other genotypes with (140.5+ 10.5), (316.2+ 9.2), and (559.1+ 24.3) ~tg g-~ of seed meal ct-, 7-, and total (T-) tocopherol, respectively, and a 0.44+0.04 ^- to 7-tocopherol ratio. The comparison of the sample preparation protocols, on the other hand, suggests that P3 is the most suitable method for the tocopherol extraction from Brassica oilseeds and for the analysis of tocopherols using gas chromatography flame ionization detector (GC-FID). Trimethylsilylation is the key step differentiating P3 from P1 and P2. Variations detected in tocopherol contents among the Chinese rapeseed (B. napus) genotypes signify the need to quantify a wide range of rapeseed germplasm for seed tocopherol dynamics in short and crop improvement in long.展开更多
Recently, drought-induced damaging impact in reducing the crop growth and development is drastically ranked at the top under various abiotic stresses. And especially water stress at the reproductive growth stages term...Recently, drought-induced damaging impact in reducing the crop growth and development is drastically ranked at the top under various abiotic stresses. And especially water stress at the reproductive growth stages termed as terminal drought has become a severe threat for mungbean productivity. To mitigate the drought stress condition, "bio-priming" has emerged as a newly agronomic and sustainable technique in improving the mungbean production. A 2-year field study during Kharif season 2017–2018 was conducted to investigate the efficacy of rhizobacteria seed priming in mungbean(AZRI mung-06), at Agronomic Research Area, Department of Agronomy, Bahauddin Zakariya University, Multan, Pakistan. The experiment comprised two factors containing FA(seed treatments, control(dry seeds), hydro-priming, silicon(Si)-priming, and bio-priming(mixture strains of Pseudomonas fluorescens+Rhizobium phaseoli)) and FB(irrigation water-regimes at various growth stages including leaf formation(L), stem elongation(S)+flowering(F)+pod formation(P) containing treatments are normal irrigation(I(L+S+F+P)) and terminal drought stress(I(F+P))). All the treatments were arranged in randomized complete block design under factorial design and were replicated thrice. Results indicated that the exposure of drought stress at flowering and pod formation stages hampered the morpho-physiological growth and yield of mungbean. Nevertheless, seed priming treatments particularly bio-priming were effective in alleviating the detrimental effects of drought stress. Bio-priming significantly increased the yield and yield components(seeds/plant, 1 000-grain weight and harvest index) of mungbean and regulated the activities/levels of antioxidants(superoxide dismutase, catalase, peroxidase, ascorbic acid, and total phenolics) under drought stress. Compared with the control, bio-priming increased the seed yield of mungbean by 8–12% under normal as well as drought stress conditions during both years of study. Bio-priming also improved the nutrient uptake behavior followed by Si-and hydro-priming treatments under terminal drought stress. The study emphasized the effectiveness of bio-priming as dual seed treatment method may be helpful for vigorous germination of mungbean production along with plant tolerance against terminal drought stress. Among the various treatments, plants treated with bio-priming technique compensated the grain yield due to having strong antioxidant defense system and better nutrient uptake behaviour under terminal drought stress. Economic analysis also concluded that bio-priming is the easiest, cost-effective, friendly, and sustainable approach for the maximization of the mungbean production.展开更多
Rapeseed (Brassica napus),an important oilseed crop,has adapted to diverse climate zones and latitudes by forming three main ecotype groups,namely winter,semiwinter,and spring types. However,genetic variations underly...Rapeseed (Brassica napus),an important oilseed crop,has adapted to diverse climate zones and latitudes by forming three main ecotype groups,namely winter,semiwinter,and spring types. However,genetic variations underlying the divergence of these ecotypes are largely unknown. Here,we report the global pattern of genetic polymorphisms in rapeseed determined by resequencing a worldwide collection of 991 germplasm accessions.A total of 5.56 and 5.53 million singlenucleotide polymorphisms (SNPs)as Well as 1.86 and 1.92 million InDels were identified by mapping reads to the reference genomes of "Darmor-bzh"and "Tapidor,"respectively.We generated a map of allelic drift paths that shows splits and mixtures of the main populations,and revealed an asymmetric evolution of the two subgenomes of B.napus by calculating the genetic diversity and linkage disequilibrium parameters.Selective-sweep analysis revealed genetic changes in genes orthologous to those regulating various aspects of plant development and response to stresses.A genome-wide association study identified SNPs in the promoter regions of FLOWERING LOCUS T and FLOWERING LOCUS C orthologs that corresponded to the different rapeseed ecotype groups. Our study provides important insights into the genomic footprints of rapeseed evolution and flowering-time divergence among three ecotype groups,and will facilitate screening of molecular markers for accelerating rapeseed breeding.展开更多
基金supported by the National Natural Science Foundation of China (30971700 and 31171463)Natural Science Foundation of Zhejiang Province (Z3100130)
文摘The variation among Chinese genotypes of Brassica napus L. for seed tocopherols content and their analysis using gas chromatography has not been comprehensively reported till to date. In the present study, the tocopherol contents of four Chinese genotypes of Brassica napus L., namely, Gaoyou 605, Zhejiang 619, Zheshuang 758, and Zheshuang 72, were evaluated using three modified sample preparation protocols (P1, P2, and P3) for tocopherol extraction. These methods were distinguished as follows. Protocol one (P1) included the evaporation of solvent after extraction without silylation. Protocol two (P2) followed the direct supernatant collection after overnight extraction without drying and silylation. Protocol three (P3) included trimethylsilylation with N,O-bis(trimethylsilyl) trifluoroacetamide. Genotypic comparison of tocopherol and its isoforms revealed that Gaoyou 605 was dominant over the other genotypes with (140.5+ 10.5), (316.2+ 9.2), and (559.1+ 24.3) ~tg g-~ of seed meal ct-, 7-, and total (T-) tocopherol, respectively, and a 0.44+0.04 ^- to 7-tocopherol ratio. The comparison of the sample preparation protocols, on the other hand, suggests that P3 is the most suitable method for the tocopherol extraction from Brassica oilseeds and for the analysis of tocopherols using gas chromatography flame ionization detector (GC-FID). Trimethylsilylation is the key step differentiating P3 from P1 and P2. Variations detected in tocopherol contents among the Chinese rapeseed (B. napus) genotypes signify the need to quantify a wide range of rapeseed germplasm for seed tocopherol dynamics in short and crop improvement in long.
文摘Recently, drought-induced damaging impact in reducing the crop growth and development is drastically ranked at the top under various abiotic stresses. And especially water stress at the reproductive growth stages termed as terminal drought has become a severe threat for mungbean productivity. To mitigate the drought stress condition, "bio-priming" has emerged as a newly agronomic and sustainable technique in improving the mungbean production. A 2-year field study during Kharif season 2017–2018 was conducted to investigate the efficacy of rhizobacteria seed priming in mungbean(AZRI mung-06), at Agronomic Research Area, Department of Agronomy, Bahauddin Zakariya University, Multan, Pakistan. The experiment comprised two factors containing FA(seed treatments, control(dry seeds), hydro-priming, silicon(Si)-priming, and bio-priming(mixture strains of Pseudomonas fluorescens+Rhizobium phaseoli)) and FB(irrigation water-regimes at various growth stages including leaf formation(L), stem elongation(S)+flowering(F)+pod formation(P) containing treatments are normal irrigation(I(L+S+F+P)) and terminal drought stress(I(F+P))). All the treatments were arranged in randomized complete block design under factorial design and were replicated thrice. Results indicated that the exposure of drought stress at flowering and pod formation stages hampered the morpho-physiological growth and yield of mungbean. Nevertheless, seed priming treatments particularly bio-priming were effective in alleviating the detrimental effects of drought stress. Bio-priming significantly increased the yield and yield components(seeds/plant, 1 000-grain weight and harvest index) of mungbean and regulated the activities/levels of antioxidants(superoxide dismutase, catalase, peroxidase, ascorbic acid, and total phenolics) under drought stress. Compared with the control, bio-priming increased the seed yield of mungbean by 8–12% under normal as well as drought stress conditions during both years of study. Bio-priming also improved the nutrient uptake behavior followed by Si-and hydro-priming treatments under terminal drought stress. The study emphasized the effectiveness of bio-priming as dual seed treatment method may be helpful for vigorous germination of mungbean production along with plant tolerance against terminal drought stress. Among the various treatments, plants treated with bio-priming technique compensated the grain yield due to having strong antioxidant defense system and better nutrient uptake behaviour under terminal drought stress. Economic analysis also concluded that bio-priming is the easiest, cost-effective, friendly, and sustainable approach for the maximization of the mungbean production.
基金the National Key Basic Research Project (no. 2015CB150205)Natural Science Foundation of China,China (no. 31671597,31370313,31670283)+1 种基金Sino-German Science Center for Research Promotion,China (GZ 1099)Jiangsu Collaborative Innovation Center for Modern Crop Production,China,and the Singapore National Research Foundation Investigatorship Program,Singapore (NRF-NRFI2016-02).
文摘Rapeseed (Brassica napus),an important oilseed crop,has adapted to diverse climate zones and latitudes by forming three main ecotype groups,namely winter,semiwinter,and spring types. However,genetic variations underlying the divergence of these ecotypes are largely unknown. Here,we report the global pattern of genetic polymorphisms in rapeseed determined by resequencing a worldwide collection of 991 germplasm accessions.A total of 5.56 and 5.53 million singlenucleotide polymorphisms (SNPs)as Well as 1.86 and 1.92 million InDels were identified by mapping reads to the reference genomes of "Darmor-bzh"and "Tapidor,"respectively.We generated a map of allelic drift paths that shows splits and mixtures of the main populations,and revealed an asymmetric evolution of the two subgenomes of B.napus by calculating the genetic diversity and linkage disequilibrium parameters.Selective-sweep analysis revealed genetic changes in genes orthologous to those regulating various aspects of plant development and response to stresses.A genome-wide association study identified SNPs in the promoter regions of FLOWERING LOCUS T and FLOWERING LOCUS C orthologs that corresponded to the different rapeseed ecotype groups. Our study provides important insights into the genomic footprints of rapeseed evolution and flowering-time divergence among three ecotype groups,and will facilitate screening of molecular markers for accelerating rapeseed breeding.
基金supported by the National Natural Science Foundation of China(Nos.31171463 and 31371542)the Chinese Ministry of Education(No.20130101110077)the Department of Science and Technology of Zhejiang Province(No.2013C32004),China