The okra germplasm was screened for salinity tolerance at the seedling stage and during plant ontogeny. Substantial variation existed in okra for salinity tolerance at the seedling stage. An 80 mmol/L NaCI concentrati...The okra germplasm was screened for salinity tolerance at the seedling stage and during plant ontogeny. Substantial variation existed in okra for salinity tolerance at the seedling stage. An 80 mmol/L NaCI concentration was suitable for discriminating tolerant and non-tolerant okra genotypes. The pooled ranking of the genotypes, based on individual rankings for each trait （root and shoot length, germination percentage, and relative Na^＋ and K%＋） in individual NaCI concentrations, was effective for selecting tolerant genotypes. Genotypes selected at the seedling stage maintained their tolerance to NaCI during plant ontogeny, suggesting that screening of the germplasm entries and advanced breeding materials for salt tolerance at the seedling stage is effective. Among 39 okra genotypes, five were identified as the most tolerant genotypes and showed potential for use in breeding programs that focus on the development of salt-tolerant, high-yield okra cultivars.展开更多
Good quality deoxyribonucleic acid （DNA） is the pre-requisite for its downstream applications. The presence of high concentrations of polysaccharides, polyphenols, proteins, and other secondary metabolites in mango ...Good quality deoxyribonucleic acid （DNA） is the pre-requisite for its downstream applications. The presence of high concentrations of polysaccharides, polyphenols, proteins, and other secondary metabolites in mango leaves poses problem in getting good quality DNA fit for polymerase chain reaction （PCR） applications. The problem is exacerbated when DNA is extracted from mature mango leaves. A reliable and modified protocol based on the cetyl trimethylammonium bromide （CTAB） method for DNA extraction from mature mango leaves is described here. High concentrations of inert salt were used to remove polysaccharides; Polyvinylpyrrolidone （PVP） and 13-mercaptoethanol were employed to man＇age phenolic compounds. Extended chloroform-isoamyl alcohol treatment followed by RNase treatment yielded 950-1050 pg of good quality DNA, free of protein and RNA. The problems of DNA degradation,contamination, and low yield due to irreversible binding of phenolic compounds and coprecipitation of polysaccharides with DNA were avoided by this method, The DNA isolated by the modified method showed good PCR amplification using simple sequence repeat （SSR） primers, This modified protocol can also be used to extract DNA from other woody plants having similar problems.展开更多
基金Project supported by the Indigenous 5000 Fellowship Program(Batch II)of the Higher Education Commission,Pakistan
文摘The okra germplasm was screened for salinity tolerance at the seedling stage and during plant ontogeny. Substantial variation existed in okra for salinity tolerance at the seedling stage. An 80 mmol/L NaCI concentration was suitable for discriminating tolerant and non-tolerant okra genotypes. The pooled ranking of the genotypes, based on individual rankings for each trait （root and shoot length, germination percentage, and relative Na^＋ and K%＋） in individual NaCI concentrations, was effective for selecting tolerant genotypes. Genotypes selected at the seedling stage maintained their tolerance to NaCI during plant ontogeny, suggesting that screening of the germplasm entries and advanced breeding materials for salt tolerance at the seedling stage is effective. Among 39 okra genotypes, five were identified as the most tolerant genotypes and showed potential for use in breeding programs that focus on the development of salt-tolerant, high-yield okra cultivars.
基金Project supported by Punjab Agricultural Research Board (PARB)the project No.150 awarded to Dr.Iqrar Ahmad KHAN,Pakistan
文摘Good quality deoxyribonucleic acid （DNA） is the pre-requisite for its downstream applications. The presence of high concentrations of polysaccharides, polyphenols, proteins, and other secondary metabolites in mango leaves poses problem in getting good quality DNA fit for polymerase chain reaction （PCR） applications. The problem is exacerbated when DNA is extracted from mature mango leaves. A reliable and modified protocol based on the cetyl trimethylammonium bromide （CTAB） method for DNA extraction from mature mango leaves is described here. High concentrations of inert salt were used to remove polysaccharides; Polyvinylpyrrolidone （PVP） and 13-mercaptoethanol were employed to man＇age phenolic compounds. Extended chloroform-isoamyl alcohol treatment followed by RNase treatment yielded 950-1050 pg of good quality DNA, free of protein and RNA. The problems of DNA degradation,contamination, and low yield due to irreversible binding of phenolic compounds and coprecipitation of polysaccharides with DNA were avoided by this method, The DNA isolated by the modified method showed good PCR amplification using simple sequence repeat （SSR） primers, This modified protocol can also be used to extract DNA from other woody plants having similar problems.
