Rice, a staple cereal crop in many parts of the world, has been confronted with multiple environmental stresses including high temperature, negatively impacts the booting as well as anthesis growth stages. The situati...Rice, a staple cereal crop in many parts of the world, has been confronted with multiple environmental stresses including high temperature, negatively impacts the booting as well as anthesis growth stages. The situation is further complicated by the changing climatic conditions, resulting in gradual escalation of temperature as well as changing the rainfall pattern and frequency, thus raising a concern of food security worldwide. The situation can be combat by developing rice varieties with excellent genetics with improved morpho-physiological, biochemical, and molecular mechanisms, together can minimize the adverse effects of heat stress. Here, several strategies(encompassing genetic and genomic, and mechanisms involved) for mitigating the impact of high temperature on rice have been discussed. Finally, the utilization of genomic knowledge in augmenting the conventional breeding approaches have been comprehensively elaborated to develop heat tolerant germplasm.展开更多
Genotyping by sequencing(GBS) is the recent approach of next-generation sequencing technique for discovering and genotyping single nucleotide polymorphisms(SNPs) in crop species. Genotypic variation studies(SNPs and i...Genotyping by sequencing(GBS) is the recent approach of next-generation sequencing technique for discovering and genotyping single nucleotide polymorphisms(SNPs) in crop species. Genotypic variation studies(SNPs and insertion-deletions/In Dels) were performed using four rice lines based on GBS data by aligning to the reference genome Nipponbare. Local aromatic rice landrace Tulaipanji was crossed with Ranjit, and two distinct lines were identified from the progenies: one line with awns and aroma traits and the other without awns and aroma. Total number of SNPs and In Dels identified were 52 810 and 4 327 at read depth 10, respectively. Out of the total polymorphic SNPs/In Dels, 16 490 were intergeneric, 7 812 were inside gene, and 4 435 were intronic. Phylogenetically, Tulaipanji was closer to the reference genome nipponbare. Based on recurrent parent genome analysis, out of 10 013 alleles, 92.52% was introgressed into progeny-awn from Tulaipanji and 7.48% from Ranjit, whereas progeny-awnless carried 89.19% alleles from Ranjit and only 10.81% alleles from Tulaipanji. In addition, progeny-awn was the highest heterozygous(83.88%) and progeny-awnless was the least(2.24%) at this fifth generation of recombinant inbred lines. These SNP variations may be linked to the phenotypic traits and can be utilized in crop improvement through linkage mapping. These results suggest that adding a high density of SNP markers to a mapping or breeding population through GBS has a great value for numerous applications in rice breeding and genetics research.展开更多
The current study investigated the comparative oxidative damage in twomaize seedlings induced by saline,drought,and combined stress and the ameliorative role of two different doses(20 and 80μM)of 5-aminolevulinic aci...The current study investigated the comparative oxidative damage in twomaize seedlings induced by saline,drought,and combined stress and the ameliorative role of two different doses(20 and 80μM)of 5-aminolevulinic acid(ALA)against the above-mentioned stresses.Hydroponically grown 10-day-old maize(Zea mays,var.BARI Hybrid Maize-7(BHM-7)and BARI Hybrid Maize-9(BHM-9))seedlings were exposed to 12 dS/m of saline solution,200 mM mannitol-induced drought stress alone and their combined stress for 7 days.Result revealed that individual stresses retard the plant growth to some degrees,however,their combined stress has more detrimental effects,which might be correlated with lipid peroxidation(MDA)-induced oxidative stress in seedlings,enhanced Na+/K+ratio,and augmented generation of superoxide(O_(2)•^(−))and hydrogen peroxide(H_(2)O_(2)).In contrast,exogenous ALA supplementation at 20μM concentration markedly recovered from chlorosis and growth inhibition,substantially scavenged reactive oxygen species(ROS)and MDA by preserving ionhomeostasis and relaxing oxidative stress,also,by boosting catalase(CAT)and glutathione S-transferase(GST),and exclusively via depressing the activity of lipoxygenase(LOX)antioxidant enzyme.On the contrary,80μM ALA made things worse,nevertheless,higher activities shown by other antioxidant enzymes,like,superoxide dismutase(SOD),ascorbate peroxidase(APX),peroxidase(POD),and glutathione peroxidase(GPX),which were related to lessen the oxidative damage by highly produced O_(2)•^(−)and H_(2)O_(2) under combined stress.Non-denaturing gel electrophoresis was done for further confirmation.However,ALA importantly increased the photosynthetic pigment contents in both genotypes irrespective of doses.Nevertheless,GST might have assisted the plants to escape from the herbicidal effect by detoxification.However,in the combined stress condition,high ALA concentration may have some positive role to play.Our findings also showed that BHM-9 performed better than BHM-7.Therefore,ALA at lower concentration was effective for single stress of saline and drought,while higher concentration can improve plant survival under combined stress.展开更多
This study was undertaken to investigate oxidative stress tolerant mechanisms in chilli(Capsicum annuum L.)under drought genotypes through evaluating morphological,physiological,biochemical and stomatal parameters.Twe...This study was undertaken to investigate oxidative stress tolerant mechanisms in chilli(Capsicum annuum L.)under drought genotypes through evaluating morphological,physiological,biochemical and stomatal parameters.Twenty genotypes were evaluated for their genetic potential to drought stress tolerant at seedling stage.Thirty days old seedlings were exposed to drought stress induced by stop watering for the following 10 days and rewatering for the following one week as recovery.Based on their survival performance,two tolerant genotypes viz.BD-10906 and BD-109012 and two susceptible genotypes viz.BD-10902 and RT-20 were selected for studying the oxidative stress tolerance mechanism.Drought reduced root and shoot length,dry weight,ratio,petiole weight and leaf area in both tolerant and susceptible genotypes,and a higher reduction was observed in susceptible genotypes.Lower reduction of leaf area and photosynthetic pigments were also found in tolerant genotypes.Moreover,tolerant genotypes showed higher recovery than susceptible genotypes after the removal of stress.A higher reduction of relative water content(RWC)may cause an imbalance between absorbed and transpirated water in susceptible genotypes.Higher accumulation of proline in tolerant genotypes might be helpful to for better osmotic maintenance than that in susceptible genotypes.Tolerant genotypes showed higher antioxidant activity as they showed DPPH radical scavenging percentage than the susceptible genotypes.Moreover,closer stomata in tolerant genotypes than susceptible ones helped to avoid dehydration in tolerant genotypes.Thus,the above morphological,physiological,biochemical and stomatal parameters helped to show better tolerance in chilli under drought stress.展开更多
To grasp protein content and composition of pea resource in Tibet Plateau,54 pea materials from different eco-geographical environments of Tibet were collected and arranged in this paper.Based on SDS-PAGE,electrophore...To grasp protein content and composition of pea resource in Tibet Plateau,54 pea materials from different eco-geographical environments of Tibet were collected and arranged in this paper.Based on SDS-PAGE,electrophoresis and genetic diversity analysis of water-solubility and salt-solubility proteins from 54 pea materials were conducted,and the relationship between geographical ecological factors(longitude,latitude and altitude) and total protein content was studied.The research results showed that total protein contents of 54 pea materials were between17.58% and 28.67%,in which water-solubility protein accounted for 86.12%-91.40%,while salt-solubility protein accounted for 4.76-8.29%.Total protein content of Tibet pea showed significantly positive correlation with longitude,certain positive correlation with latitude and certain negative correlation with altitude.SDS-PAGE of water-solubility and salt-solubility proteins from 54 pea materials respectively detected 1588 and 699 protein bands.Based on different mobility ratios,there were 43 kinds of water-solubility protein bands,and diversity index was between 0 and 0.5.Its relative molecular weight was between 24.87 and 149.54 ku,showing the low molecular weight region of24.71-50.41 ku and high molecular weight region of 56.34-88.08 ku.There were 24 salt-solubility protein bands based on different mobility ratios,with the diversity index of 0-0.5,and relative molecular weight was between 24.85 and 91.24 ku.According to the altitude,54 pea resources were divided into 4 geographical groups.Gene diversity indexes of each group were respectively 0.23,0.18,0.35 and 0.31,and Shannon information indexes were respectively 0.33,0.41,0.52 and 0.46.It showed that the variation of pea protein was related to altitude.In clustering analysis,the tested resources were divided into seven classes,showing that water-solubility and salt-solubility proteins could reflect genetic relationship among germplasm resources at certain degree.The research could provide theoretical basis for the development of Tibet pea resources and selection of good parents.展开更多
文摘Rice, a staple cereal crop in many parts of the world, has been confronted with multiple environmental stresses including high temperature, negatively impacts the booting as well as anthesis growth stages. The situation is further complicated by the changing climatic conditions, resulting in gradual escalation of temperature as well as changing the rainfall pattern and frequency, thus raising a concern of food security worldwide. The situation can be combat by developing rice varieties with excellent genetics with improved morpho-physiological, biochemical, and molecular mechanisms, together can minimize the adverse effects of heat stress. Here, several strategies(encompassing genetic and genomic, and mechanisms involved) for mitigating the impact of high temperature on rice have been discussed. Finally, the utilization of genomic knowledge in augmenting the conventional breeding approaches have been comprehensively elaborated to develop heat tolerant germplasm.
基金the Authority of the University of North Bengal for giving financial assistance and field work facility to carry out this Research Project on Molecular Breeding on Rice(2015–2016)
文摘Genotyping by sequencing(GBS) is the recent approach of next-generation sequencing technique for discovering and genotyping single nucleotide polymorphisms(SNPs) in crop species. Genotypic variation studies(SNPs and insertion-deletions/In Dels) were performed using four rice lines based on GBS data by aligning to the reference genome Nipponbare. Local aromatic rice landrace Tulaipanji was crossed with Ranjit, and two distinct lines were identified from the progenies: one line with awns and aroma traits and the other without awns and aroma. Total number of SNPs and In Dels identified were 52 810 and 4 327 at read depth 10, respectively. Out of the total polymorphic SNPs/In Dels, 16 490 were intergeneric, 7 812 were inside gene, and 4 435 were intronic. Phylogenetically, Tulaipanji was closer to the reference genome nipponbare. Based on recurrent parent genome analysis, out of 10 013 alleles, 92.52% was introgressed into progeny-awn from Tulaipanji and 7.48% from Ranjit, whereas progeny-awnless carried 89.19% alleles from Ranjit and only 10.81% alleles from Tulaipanji. In addition, progeny-awn was the highest heterozygous(83.88%) and progeny-awnless was the least(2.24%) at this fifth generation of recombinant inbred lines. These SNP variations may be linked to the phenotypic traits and can be utilized in crop improvement through linkage mapping. These results suggest that adding a high density of SNP markers to a mapping or breeding population through GBS has a great value for numerous applications in rice breeding and genetics research.
文摘The current study investigated the comparative oxidative damage in twomaize seedlings induced by saline,drought,and combined stress and the ameliorative role of two different doses(20 and 80μM)of 5-aminolevulinic acid(ALA)against the above-mentioned stresses.Hydroponically grown 10-day-old maize(Zea mays,var.BARI Hybrid Maize-7(BHM-7)and BARI Hybrid Maize-9(BHM-9))seedlings were exposed to 12 dS/m of saline solution,200 mM mannitol-induced drought stress alone and their combined stress for 7 days.Result revealed that individual stresses retard the plant growth to some degrees,however,their combined stress has more detrimental effects,which might be correlated with lipid peroxidation(MDA)-induced oxidative stress in seedlings,enhanced Na+/K+ratio,and augmented generation of superoxide(O_(2)•^(−))and hydrogen peroxide(H_(2)O_(2)).In contrast,exogenous ALA supplementation at 20μM concentration markedly recovered from chlorosis and growth inhibition,substantially scavenged reactive oxygen species(ROS)and MDA by preserving ionhomeostasis and relaxing oxidative stress,also,by boosting catalase(CAT)and glutathione S-transferase(GST),and exclusively via depressing the activity of lipoxygenase(LOX)antioxidant enzyme.On the contrary,80μM ALA made things worse,nevertheless,higher activities shown by other antioxidant enzymes,like,superoxide dismutase(SOD),ascorbate peroxidase(APX),peroxidase(POD),and glutathione peroxidase(GPX),which were related to lessen the oxidative damage by highly produced O_(2)•^(−)and H_(2)O_(2) under combined stress.Non-denaturing gel electrophoresis was done for further confirmation.However,ALA importantly increased the photosynthetic pigment contents in both genotypes irrespective of doses.Nevertheless,GST might have assisted the plants to escape from the herbicidal effect by detoxification.However,in the combined stress condition,high ALA concentration may have some positive role to play.Our findings also showed that BHM-9 performed better than BHM-7.Therefore,ALA at lower concentration was effective for single stress of saline and drought,while higher concentration can improve plant survival under combined stress.
基金supported by the R&D projects of Ministry of Science and Technology,Government of the Bangladesh.
文摘This study was undertaken to investigate oxidative stress tolerant mechanisms in chilli(Capsicum annuum L.)under drought genotypes through evaluating morphological,physiological,biochemical and stomatal parameters.Twenty genotypes were evaluated for their genetic potential to drought stress tolerant at seedling stage.Thirty days old seedlings were exposed to drought stress induced by stop watering for the following 10 days and rewatering for the following one week as recovery.Based on their survival performance,two tolerant genotypes viz.BD-10906 and BD-109012 and two susceptible genotypes viz.BD-10902 and RT-20 were selected for studying the oxidative stress tolerance mechanism.Drought reduced root and shoot length,dry weight,ratio,petiole weight and leaf area in both tolerant and susceptible genotypes,and a higher reduction was observed in susceptible genotypes.Lower reduction of leaf area and photosynthetic pigments were also found in tolerant genotypes.Moreover,tolerant genotypes showed higher recovery than susceptible genotypes after the removal of stress.A higher reduction of relative water content(RWC)may cause an imbalance between absorbed and transpirated water in susceptible genotypes.Higher accumulation of proline in tolerant genotypes might be helpful to for better osmotic maintenance than that in susceptible genotypes.Tolerant genotypes showed higher antioxidant activity as they showed DPPH radical scavenging percentage than the susceptible genotypes.Moreover,closer stomata in tolerant genotypes than susceptible ones helped to avoid dehydration in tolerant genotypes.Thus,the above morphological,physiological,biochemical and stomatal parameters helped to show better tolerance in chilli under drought stress.
基金Supported by National Natural Fund(31560362)Key Item of Tibet Autonomous Region(XZXTCX-2016)Innovation Support Plan of Young Teacher in Tibet Colleges and Universities(QC2015-35)
文摘To grasp protein content and composition of pea resource in Tibet Plateau,54 pea materials from different eco-geographical environments of Tibet were collected and arranged in this paper.Based on SDS-PAGE,electrophoresis and genetic diversity analysis of water-solubility and salt-solubility proteins from 54 pea materials were conducted,and the relationship between geographical ecological factors(longitude,latitude and altitude) and total protein content was studied.The research results showed that total protein contents of 54 pea materials were between17.58% and 28.67%,in which water-solubility protein accounted for 86.12%-91.40%,while salt-solubility protein accounted for 4.76-8.29%.Total protein content of Tibet pea showed significantly positive correlation with longitude,certain positive correlation with latitude and certain negative correlation with altitude.SDS-PAGE of water-solubility and salt-solubility proteins from 54 pea materials respectively detected 1588 and 699 protein bands.Based on different mobility ratios,there were 43 kinds of water-solubility protein bands,and diversity index was between 0 and 0.5.Its relative molecular weight was between 24.87 and 149.54 ku,showing the low molecular weight region of24.71-50.41 ku and high molecular weight region of 56.34-88.08 ku.There were 24 salt-solubility protein bands based on different mobility ratios,with the diversity index of 0-0.5,and relative molecular weight was between 24.85 and 91.24 ku.According to the altitude,54 pea resources were divided into 4 geographical groups.Gene diversity indexes of each group were respectively 0.23,0.18,0.35 and 0.31,and Shannon information indexes were respectively 0.33,0.41,0.52 and 0.46.It showed that the variation of pea protein was related to altitude.In clustering analysis,the tested resources were divided into seven classes,showing that water-solubility and salt-solubility proteins could reflect genetic relationship among germplasm resources at certain degree.The research could provide theoretical basis for the development of Tibet pea resources and selection of good parents.
