Revealing contrasting genetic variation and study of genetic diversity in urdbean (Vigna mungo (L.) Hepper) using SDS-PAGE of seed storage proteins

Total seed storage protein profiles of 20 urdbean genotypes including the popular variety T9 were analysed by Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). 14 genotypes could be clearly identified based on genotype-specific seed protein fingerprints while rest of the test genotypes were categorized into three protein types. Dendrogram based on electrophoretic data clustered the genotypes into seven groups at 78.5% phenon level.  TU 95-1 with TU 12-25-4 revealed lowest similarity index value (0.33) followed by TU 95-1 with PU 30 and KU 96-3(SI=0.35). Clustering pattern revealed distinctly divergent group formed by TPU 95-1 and TPU 4. These may serve as a valuable source genotype in recombination breeding.   Key words: Seed storage protein profiling, SDS-PAGE, Genetic variation, urdbean

Identification of seed storage protein markers for drought tolerance in mungbean

A set of 292 mungbean germplasm accessions including 62 popularly adapted local land races and two wild forms (Vigna radiata var. sublobata), important breeding lines and standard ruling varieties were screened for drought stress tolerance at seedling stage.  Eight genotypes e.g., C. No. 35, OUM 14-1, OUM 49-2, Pusa 9072, OM 99-3, Banapur local B, Nipania munga, Kalamunga 1-A) have been identified to possess drought tolerance.  Globulin seed storage protein profiling was carried out in 19 selected mungbean genotypes comprising eight drought tolerant, seven drought sensitive, two wild forms of mungbean (TCR 20 and TCR 213) and two standard checks (LGG 460 and T 2-1) to explore differentially expressed polypeptides. Seed protein profiles revealed 15 scorable polypeptide bands with molecular weights ranging from 10.0 to 102.2kD. A specific 12.8kD polypeptide band was present in all above drought tolerant test genotypes including the wild accession TCR 20. Such a polypeptide band may serve as useful biochemical marker for identification of drought tolerant genotypes in mungbean.             Key words: Genetic diversity, seed storage protein profile, wild and cultivated Vigna radiata

Globulin seed storage protein based genotyping and Study of genetic diversity in core accessions of mungbean under drought stress

Globulin seed storage protein profiles of 19 mungbean genotypes including two wild forms of Vigna radiata var. sublobata(TCR 20 and TCR 213) and two standard  checks(T 2-1 and LGG 460) were analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Thirteen genotypes could be clearly identified based on genotype-specific seed protein fingerprints. The combined dendrogram showed six genetic clusters within 68% phenon level. The clustering based on the combined clustering analysis revealed discrimination of all test genotypes even immediately beyond 88% phenon level, whereas individual clustering analysis based on protein and agro-morphological level failed to do so. Nipania munga, TCR 213, T 2-1, LGG 460, TCR 20 and Banapur local B were identified to be highly divergent genotypes. TCR 20 appears to have more genetic proximity to the mungbean genotypes than TCR 213. T 2-1, LGG 460 and TCR 20 are potentially high yielding. These may serve as valuable materials for recombination breeding in mungbean

Gene actions and combining ability effects on grain yield and its constituent traits in inbred lines of quality protein maize

In the present study twenty-eight hybrid combinations resulting from the half-diallel mating of eight quality protein maize (QPM) inbred lines were chosen in order to examine the potential to combine and gene activity for ten yield and component attributes. As part of the All India Coordinated Research Project (AICRP) on maize during the kharif-2020 season, the experiment was done at the research farm of college of Agriculture, Odisha University of Agriculture & Technology (OUAT) Bhubaneswar, using a randomized complete block design replicated thrice. Every observation recorded was subjected to statistical evaluation and it was revealed that the mean squares derived from the general combining ability (gca) and specific combining ability (sca) were highly significant (p ≥0.01). Estimates of sca effects   were greater than that of gca effects for all of the variables used in the study, suggesting to the predominance of dominant gene action. The inbred lines Q4-DQL 2221-1-1(833.792), Q2-DQL 2099 (517.658) and Q3- DQL 2159 (350.325) shows high gca effects for yield and its attributing traits due to more additive gene action thus identified as good general combiners for yield. Twelve of the twenty-eight crosses showed significant (p ≥0.01 and 0.05) positive sca effect on grain yield. The best experimental crosses for grain yield based on per se performance and sca effects were Q2 x Q8 (2106.748), Q1 x Q6 (2053.048), Q3 x Q7 (2027.082), and Q3 x Q6 (1719.884)

Biochemical characterization of maize (Zea mays L.) hybrids under excessive soil moisture stress

A set of 32 maize hybrids were evaluated under excessive soil moisture (ESM) stress. The plants were subjected to waterlogging for 12 days at the flowering stage by maintaining 3–5 cm water level. Physiological and biochemical traits were examined to analyze plants’ response to waterlogging stress. The chlorophyll a, b and total chlorophyll content declined due to ESM stress, and the decrease was relatively higher in the case of susceptible hybrids. The decrease in chlorophyll content had shown a significant impact on total carbohydrate content, but the tolerant hybrids thrive better under stress with a capacity to maintain higher carbohydrate concentration. Proline accumulation was enhanced in all hybrids in response to the above stress, but it was tremendously increased in tolerant hybrids to offer osmotic protection compared to the sensitive genotypes. Total chlorophyll, chlorophyll-a, carbohydrate, proline as well as an increase in proline content in response to stress, revealed a significant positive association with seed yield, while percentage decline in chlorophyll, decrease in carbohydrate and senescence percentage maintained the reverse trend. Further, the chlorophyll ‘a' followed by an increase in proline content can be considered as important parameters for assessing tolerance to ESM stress owing to their high positive direct effects on seed yield

Association Mapping for Quantitative Trait Loci Controlling Superoxide Dismutase, Flavonoids, Anthocyanins, Carotenoids, γ-Oryzanol and Antioxidant Activity in Rice

Antioxidant-rich rice is a cheaper way to solve stress-related disorders and other health benefits for the global rice-eating population. Five antioxidant traits, namely, superoxide dismutase, flavonoids, anthocyanins, γ-oryzanol and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) activity were mapped using a representative panel population through association mapping. Potential landraces carrying multiple antioxidant compounds were identified from the population. The population represented four genetic groups and correspondence for presence of antioxidants traits in each group was noticed. The population showed linkage disequilibrium for the studied traits based on the Fst values. A total of 14 significant marker–trait associations were detected for these antioxidant traits. The study validated the QTLs, qANC3 and qPAC12-2 for anthocyanin content and qAC12 for ABTS activity will be useful in marker-assisted breeding. Eleven QTLs such as qTAC1.1 and qTAC5.1 controlling anthocyanin content, qSOD1.1, qSOD5.1 and qSOD10.1 for superoxide dismutase (SOD), qTFC6.1, qTFC11.1 and qTFC12.1 for total flavonoids content (TFC), qOZ8.1 and qOZ11.1 for γ-oryzanol (OZ) and qAC11.1 for ABTS activity were detected as novel loci. Chromosomal locations on 11 at 45.3 cM regulating GO, TFC and TAC, and on the chromosome 12 at 101.8 cM controlling TAC and ABTS activity, respectively, were detected as antioxidant hotspots

Revealing contrasting genetic variation and study of genetic diversity in urdbean (Vigna mungo (L.) Hepper) using SDS-PAGE of seed storage proteins

Total seed storage protein profiles of 20 urdbean genotypes including the popular variety T9 were analysed by Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). 14 genotypes could be clearly identified based on genotype-specific seed protein fingerprints while rest of the test genotypes were categorized into three protein types. Dendrogram based on electrophoretic data clustered the genotypes into seven groups at 78.5% phenon level.  TU 95-1 with TU 12-25-4 revealed lowest similarity index value (0.33) followed by TU 95-1 with PU 30 and KU 96-3(SI=0.35). Clustering pattern revealed distinctly divergent group formed by TPU 95-1 and TPU 4. These may serve as a valuable source genotype in recombination breeding.   Key words: Seed storage protein profiling, SDS-PAGE, Genetic variation, urdbean