CHARACTERIZATION OF MAIZE (Zea mays L.) GENOTYPES USING MORPHOPHYSIOLOGICAL TRAITS AND MOLECULAR MARKER
| dc.contributor.advisor | Manigopa Chakraborty | |
| dc.contributor.author | Priyanka Kumari | |
| dc.date.accessioned | 2023-11-14T15:02:14Z | |
| dc.date.available | 2023-11-14T15:02:14Z | |
| dc.date.issued | 2023 | |
| dc.description.abstract | Maize (Zea mays L.) belongs to family, Poaceae, having worldwide growing versatility ranges from 58° N to 40° S; from below sea level to altitudes higher than 3000 m and in areas with 250 mm to more than 5000 mm of rainfall per year. Germplasm distribution across the world’s geographical area represents the wide spectrum of exploitable genetic variability for specific purpose like higher productivity or quality or combination thereof under drought stress. Drought stress being the integral part of any agro-ecosystem affecting the growth and development of crop plants. Drought is one of the major constraints in deciding maize productivity all over the world. In India, out of total maize area about 4.0 million hectares are prone to drought. Drought effects the growth and development of plants in variety of ways. For development of drought tolerant maize cultivars, the knowledge of critical sensitive stages and consequences of moisture stress, variability of germplasm, screening techniques and breeding strategies to be adopted are having very crucial importance for getting the effective result. Classical and/or molecular breeding approaches can be adopted for incorporation of available drought stress tolerant genes in appropriate genetic background. The present experiment was conducted to identify the inbreds and hybrids suitable for irrigated (30kpa) and moisture stress (50kpa) for that significant traits to be used for selection under theses environments. To determine best selection method, mean performance values, correlation coefficient, components of variance and heritability, diversity, Stress tolerance indices were analysed. Keeping above facts in mind 4 testers (drought tolerant) and 8 lines were used for development of thirty two single cross hybrids to study the genetics of yield and yield attributes under normal moisture (30kpa) and under, moisture stress condition (50kpa). Twelve parents (8 lines and 4 testers) were mated in LX T mating design, thirty two hybrids were developed and compared with checks (CM600 (inbreds), Suwan Composite, BAUMH-5 (hybrids), 1532 X Suwan (hybrids)). All the forty eight genotypes were evaluated at Research Farm, Birsa Agricultural University, Kanke, Ranchi, Jharkhand, during kharif 2020 seasons. Extensive phenotyping for morphophysiological characters along with stress indices were done for all the trials. The experimental materials were found to be significantly different from each other for all the characters under normal moisture (30kpa) and under, moisture stress condition (50kpa) and this is evident from the analysis of variance for RBD. This showed the inherent genetic difference among the genotypes under study. Correlation studies delineated that crop yield under moisture stress indicated highly significant positive genotypic and phenotypic correlation with plant height, ear height, number of plants with grain yield and number of kernels per row. This suggested that these characters can be considered for selection of plants tolerant to moisture stress. This reflected preponderance of nonadditive gene action in controlling these traits which further suggested reliable crop improvement through selection of such traits. Different genotypes responded differentially under different environments for the expression of different quantitative traits. The genotype which performs well in one environment may not perform same on the other environments. Grain yields were higher under the optimum environment compared to stress environments. Four tester parents BAUIM-1, BAUIM-2, BAUIM-5, IC622968 were found to be significantly superior stress condition for maximum number of traits including grain yield (GY/P) and yield attributing traits. These tester parents may be used for development of improved lines and hybrids for the respective environments where they were found to be significant. All the thity two Hybrids viz., IC624174 XBAUIM-2, IC624159 X BAUIM-2, IC624148 X BAUIM-2, IC624160 X BAUIM-2, IC624180 X BAUIM-2,IC624161X BAUIM-2, IC624157 XBAUIM-2, IC624151 X BAUIM-2, IC624174 XIC622968, IC624159 XIC622968, IC624148 XIC622968, IC624160XIC622968, IC624180X IC622968, IC624161 XIC622968, IC624157 X IC622968, IC624151 XIC622968, IC624174 XBAUIM-5, IC624159 XBAUIM-5, IC624148 XBAUIM-5, IC624160X BAUIM-5, IC624180 X BAUIM-5, IC624161X BAUIM-5, IC624157X BAUIM-5, IC624151 XBAUIM-5, IC624174 XBAUIM-1, IC624159 X BAUIM-1, IC624148 X BAUIM-1, IC624160 X BAUIM-1, IC624180 XBAUIM-1, IC624161 XBAUIM-1, IC624157 X BAUIM-1, IC624151 X BAUIM-1 under stress condition were found to be significantly superior for maximum number of traits than the best check including grain yield (GY/P ) observed through the standard heterosis. These superior hybrids may be used for cultivation or development of superior segregants depending upon their gene action and effect. The analysis of variances for L x T analysis under normal moisture condition (30kpa) and moisture stress (50kpa) revealed significant difference in environments for all the forty six morphophysiological traits confirming diverse nature of environments selected, which influenced the expression of the traits studied among each other in relation to the performance of the genotypes. All The traits showed non-additive genetic variance with over dominance effect of genes under all the environmental situations indicating the over expression of heterozygous loci for these characters. The predominance of non-additive gene action on implies that breeding gains can be made via inbreeding followed by crossbreeding. The type of genetic effects for grain yield is highly variable, depending on the type of parents and environments under consideration. Molecular analysis indicated that the genotypes IC622968 and IC624176 were the most diverse ones. These diverse parents can be used for development of superior hybrids and segregants tolerant to stress condition. These superior hybrids may be used for cultivation or development of superior segregants depending upon their gene action and effect. The hybrids were good performer (heterotic) across the different moisture regimes under variable moisture regimes. These hybrids may be recommended for cultivation under wide range of environment. For leaf characters angle between blade and stem under irrigated condition and non-irrigated condition maximum frequency of (55.55%) and (72.22%) as found for “small” state of expression while minimum frequency (4.44) found for “medium” state of expression under moisture stress condition. AMOVA (Analysis of molecular variance) revealed mean sum of squares due to genotypes showed highly significant differences for all the traits under study at 5% and 1% level of significance. In molecular Dendrogram picture using Jaccard’s similarity coefficient ranged from 0.52 to 0.95. Further this 2 main clusters were classified into 6 subcluster. Further, Cluster A showed four subcluster and Cluster B showed two subcluster. | |
| dc.identifier.uri | https://krishikosh.egranth.ac.in/handle/1/5810201136 | |
| dc.language.iso | English | |
| dc.pages | 211 | |
| dc.publisher | Birsa Agricultural University, Ranchi | |
| dc.sub | Genetics and Plant Breeding | |
| dc.theme | CHARACTERIZATION OF MAIZE (Zea mays L.) GENOTYPES USING MORPHOPHYSIOLOGICAL TRAITS AND MOLECULAR MARKER | |
| dc.these.type | Ph.D | |
| dc.title | CHARACTERIZATION OF MAIZE (Zea mays L.) GENOTYPES USING MORPHOPHYSIOLOGICAL TRAITS AND MOLECULAR MARKER | |
| dc.type | Thesis |