DNA methylation, an important epigenetic modification, serves as a key function in the polyploidization of numerous crops. In this study, early generations of resynthesized Brassica napus （F1,S1-S3）, ancestral paren...DNA methylation, an important epigenetic modification, serves as a key function in the polyploidization of numerous crops. In this study, early generations of resynthesized Brassica napus （F1,S1-S3）, ancestral parents B. rapa and B. oleracea were analyzed to characterize their DNA methylation status during polyploidization, applying DNA methylation-sensitive amplifica- tion polymorphism （MSAP） and high-performance liquid chromatography methods. In F, 53.4% fragments were inherited from both A- and C-genomes. Besides, 5.04 and 8.87% fragments in F were inherited from A- and C- genome, respectively. 5.85 and 0.8% fragments were newly appeared and disappeared in resynthesized B. napus, respectively. 13.1% of these gene sites were identified with methylation changes in F, namely, hypermethylation （7.86%） and hypomethylation （5.24%）. The lowest methylation status was detected in F （38.7%） compared with in S1-S3. In S3, 40.32% genes were methylated according to MSAP analysis. Sequencing of methylated fragments indicated that genes involved in multiple biological processes were modified, including transcription factors, protein modification, and transporters. Expression ananlysis of DNA methyltransferase I and DNA methyltransferase chromomethylase 3 in different materials was consistent to the DNA methylation status. These results can generally facilitate dissection of how DNA methylation contributes to genetic stability and improvement of B. napus during polypLoidization.展开更多
In the last decade,some disease occurred on our experimental farms that had caused serious losses.They were not caused by fungi,bacteria or viruses.By loop-mediated isothermal amplification(LAMP)technique,the detectio...In the last decade,some disease occurred on our experimental farms that had caused serious losses.They were not caused by fungi,bacteria or viruses.By loop-mediated isothermal amplification(LAMP)technique,the detection results pointed to the possible pathogen as phytoplasma.The investigation results implied that phytoplasmas could cause more than 13 kinds of symptoms in almost all parts of plants in B.napus L.,including witches’broom,multi-stems,aggregate main inflorescences,and flat stems.The incidences of these phytoplasma-associated diseases in our experimental farms rose from 1.61%in 2010 to 6.00%in 2021.Some phytoplasma infected plants died without any growing points.These studies would be helpful for detecting phytoplasmas diseases,selecting disease resistant germplasm and improving varieties with disease resistances in B.napus L.展开更多
Nitrogen(N)assimilation is a wide pathway in plants because of its fundamental importance for growth and development.The transport,assimilation and recycling of nitrogen is a highly complex and regulated process,as it...Nitrogen(N)assimilation is a wide pathway in plants because of its fundamental importance for growth and development.The transport,assimilation and recycling of nitrogen is a highly complex and regulated process,as it is the mineral nutrient that is required in great abundance by the plants.Basic approach to enhance agriculture sustainability is dependent on exploration of the elite germplasm where new cultivars could perform better even under low N.To test the effect of nitrogen levels at 100 and 125 kg ha-1 on photosynthetic pigments and N assimilation in oilseed rape(B.napus L.)canola variety GSC-7 and hybrid Hyola PAC 401 were selected for comparison with new hybrid PGSH-52 in pipeline.N assimilating enzymes were assayed at vegetative,flowering and siliquing stages of crop growth to visualise the impact of N on the productivity.Nitrogen assimilating enzymes were highest at flowering stage and enhanced with increased N level.Nitrate reductase(NR)activity improved by 11.5%,nitrite reductase(NiR)by 24.2%,glutamine synthetase(GS)by 12.2%and glutamate synthase(GOGAT)by 35.2%over recommended N dose(N100)at flowering stage.Hyola PAC 401 registered maximum enzymatic activities trailed by GSC-7 at all the three stages of crop growth.Differences existed within the genotypes for photosynthetic pigments which varied with N levels.Chlorophyll a,chlorophyll b,total chlorophyll and carotenoids increased with nitrogen at 125 kg N ha^(-1)whereas chlorophyll a/b declined at three stages of crop growth.At flowering total chlorophyll and carotenoids were maximum and enhanced by 12.8%and 5%respectively with higher nitrogen level.展开更多
Long developmental stage and late harvest time of winter rapeseed (Brassica napus L.) have great negative effects on rice planting of rice-rapeseed farming system in China. Early maturity improvement of rapeseed is ne...Long developmental stage and late harvest time of winter rapeseed (Brassica napus L.) have great negative effects on rice planting of rice-rapeseed farming system in China. Early maturity improvement of rapeseed is necessary. ‘Zhongshuang 11’, an elite winter rapeseed cultivar, was used in consecutive field experiments during 2010-2012. At initial flowering stage, plants were consecutively sprayed with 0.1 mg/L 2-4-Epibrassinolide(BR) for 3 d. Two hundred sampling pods from different plants were randomly collected to measure seed related indexes with a 4 d interval from 7 to 47 d after peak anthesis (DAPA).Seed color turned light brown at 31 or 35 DAPA after BR treatment, seed dry weight (DWT)was increased while seed moisture content (SMC) was decreased during seed development.DWT almost reached the maximum value when SMC was 33.20% at 31 DAPA in 2010-2011 and 35.29% at 35 DAPA in 2011-2012 growing season after BR treatment. Similarly,the maximum values of standard germination test (SGT), accelerated aging test (AAT)and cold test (CT) were observed at 31 or 35 DAPA after BR treatment respectively. The high yield and seed oil content appeared at 31 or 35 DAPA accompanied with rapid decrease in total non-structural carbohydrate (TNC) in stems and leaves. Our study indicated that BR application advanced maturity of winter rapeseed by 4 to 8 days.展开更多
基金supported by the National Key Basic Research Program of China (2015CB150201)the National Natural Science Foundation of China (NSFC, 31330057, 31401414)+2 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions of Chinathe Jiangsu Province Science Foundation, China (BK20140478, 14KJB210008)the Jiangsu Province Graduate Inno vation Fund, China (KYZZ15_0367)
文摘DNA methylation, an important epigenetic modification, serves as a key function in the polyploidization of numerous crops. In this study, early generations of resynthesized Brassica napus （F1,S1-S3）, ancestral parents B. rapa and B. oleracea were analyzed to characterize their DNA methylation status during polyploidization, applying DNA methylation-sensitive amplifica- tion polymorphism （MSAP） and high-performance liquid chromatography methods. In F, 53.4% fragments were inherited from both A- and C-genomes. Besides, 5.04 and 8.87% fragments in F were inherited from A- and C- genome, respectively. 5.85 and 0.8% fragments were newly appeared and disappeared in resynthesized B. napus, respectively. 13.1% of these gene sites were identified with methylation changes in F, namely, hypermethylation （7.86%） and hypomethylation （5.24%）. The lowest methylation status was detected in F （38.7%） compared with in S1-S3. In S3, 40.32% genes were methylated according to MSAP analysis. Sequencing of methylated fragments indicated that genes involved in multiple biological processes were modified, including transcription factors, protein modification, and transporters. Expression ananlysis of DNA methyltransferase I and DNA methyltransferase chromomethylase 3 in different materials was consistent to the DNA methylation status. These results can generally facilitate dissection of how DNA methylation contributes to genetic stability and improvement of B. napus during polypLoidization.
基金the financial support provided by project of Science and Technology Tackling Key Problems in Henan Province(Grant No.182102110430)the National Key Research and Development Program of China(Grant No.2016YFD0101300)by China Agricultural Research system(CARS-12).
文摘In the last decade,some disease occurred on our experimental farms that had caused serious losses.They were not caused by fungi,bacteria or viruses.By loop-mediated isothermal amplification(LAMP)technique,the detection results pointed to the possible pathogen as phytoplasma.The investigation results implied that phytoplasmas could cause more than 13 kinds of symptoms in almost all parts of plants in B.napus L.,including witches’broom,multi-stems,aggregate main inflorescences,and flat stems.The incidences of these phytoplasma-associated diseases in our experimental farms rose from 1.61%in 2010 to 6.00%in 2021.Some phytoplasma infected plants died without any growing points.These studies would be helpful for detecting phytoplasmas diseases,selecting disease resistant germplasm and improving varieties with disease resistances in B.napus L.
文摘Nitrogen(N)assimilation is a wide pathway in plants because of its fundamental importance for growth and development.The transport,assimilation and recycling of nitrogen is a highly complex and regulated process,as it is the mineral nutrient that is required in great abundance by the plants.Basic approach to enhance agriculture sustainability is dependent on exploration of the elite germplasm where new cultivars could perform better even under low N.To test the effect of nitrogen levels at 100 and 125 kg ha-1 on photosynthetic pigments and N assimilation in oilseed rape(B.napus L.)canola variety GSC-7 and hybrid Hyola PAC 401 were selected for comparison with new hybrid PGSH-52 in pipeline.N assimilating enzymes were assayed at vegetative,flowering and siliquing stages of crop growth to visualise the impact of N on the productivity.Nitrogen assimilating enzymes were highest at flowering stage and enhanced with increased N level.Nitrate reductase(NR)activity improved by 11.5%,nitrite reductase(NiR)by 24.2%,glutamine synthetase(GS)by 12.2%and glutamate synthase(GOGAT)by 35.2%over recommended N dose(N100)at flowering stage.Hyola PAC 401 registered maximum enzymatic activities trailed by GSC-7 at all the three stages of crop growth.Differences existed within the genotypes for photosynthetic pigments which varied with N levels.Chlorophyll a,chlorophyll b,total chlorophyll and carotenoids increased with nitrogen at 125 kg N ha^(-1)whereas chlorophyll a/b declined at three stages of crop growth.At flowering total chlorophyll and carotenoids were maximum and enhanced by 12.8%and 5%respectively with higher nitrogen level.
文摘Long developmental stage and late harvest time of winter rapeseed (Brassica napus L.) have great negative effects on rice planting of rice-rapeseed farming system in China. Early maturity improvement of rapeseed is necessary. ‘Zhongshuang 11’, an elite winter rapeseed cultivar, was used in consecutive field experiments during 2010-2012. At initial flowering stage, plants were consecutively sprayed with 0.1 mg/L 2-4-Epibrassinolide(BR) for 3 d. Two hundred sampling pods from different plants were randomly collected to measure seed related indexes with a 4 d interval from 7 to 47 d after peak anthesis (DAPA).Seed color turned light brown at 31 or 35 DAPA after BR treatment, seed dry weight (DWT)was increased while seed moisture content (SMC) was decreased during seed development.DWT almost reached the maximum value when SMC was 33.20% at 31 DAPA in 2010-2011 and 35.29% at 35 DAPA in 2011-2012 growing season after BR treatment. Similarly,the maximum values of standard germination test (SGT), accelerated aging test (AAT)and cold test (CT) were observed at 31 or 35 DAPA after BR treatment respectively. The high yield and seed oil content appeared at 31 or 35 DAPA accompanied with rapid decrease in total non-structural carbohydrate (TNC) in stems and leaves. Our study indicated that BR application advanced maturity of winter rapeseed by 4 to 8 days.
基金Supported by "11thFive-Year" Crop Breeding Research of SichuanProvince "11thFive-Year" Joint Breeding Research Project Fun-ding of Sichuan Province.~~
