Browsing by Author "JAGMEET SINGH"
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ThesisItem Open Access CHARACTERIZATION AND GENOME WIDE ASSOCIATION STUDIES FOR INSECT RESISTANCE AND YIELD IN POTATO(UHF,NAUNI, 2023-10-12) JAGMEET SINGH; DHARMINDER KUMARABSTRACT The present investigation was planned to assess theABSTRACT The present investigation was planned to assess the genetic variability, correlation among tuber yield and its component traits, their direct and indirect effects on tuber yield, clustering pattern of genotypes, and genome-wide association studies for Tuta absoluta resistance and yield components in potato. The experimental material comprising of 357 potato genotypes including varieties, advanced breeding lines and exotic germplasm was evaluated in augmented block design for two consecutive years during the winter seasons of 2021-22 and 2022-23 at Nagrota Bagwan, Kangra, Himachal Pradesh. Data were recorded on average tuber yield per plant and 22 morphological and biochemical traits in addition to 5 entomological traits. Sufficient genetic variability was observed for yield and its related traits. Based on adjusted mean values, it was revealed that Kufri Garima, CP 3585, CP 1767, CP 2390 and CP 1989 were the superior/desirable performing genotype mainly due to the significant contribution of the number of tubers per plant and average tuber weight. High PCV and GCV were observed for the number of stems per hill, plant height, number of compound leaves per plant, number of tubers per plant, average tuber weight, average tuber yield per plant, total polyphenols and total carotenoids content irrespective of years. High heritability coupled with high genetic advance was observed for majority of traits during both the years indicating the importance of additive gene action for the inheritance of these traits. Correlation and path analysis revealed that the number of tubers per plant and average tuber weight in addition to tuber dry matter content could be advantageous for developing high-yielding genotypes. The cluster analysis revealed maximum inter-cluster distance between CP 3081 and JEX/A 683, JEX/A 19 and CP 3091, JEX/A 1081 and CP 4594 during 2021-22, 2022-23 and pooled over the years, respectively. GWAS analysis indicated significant marker-trait associations for different traits viz., tuber dry matter content, number of compound leaves per plant, plant height, non-reducing sugars, tuber width, leaf damage and total plant damage. Further it was observed that one SNP for plant height (chr04_3551782), two SNPs number of compound leaves per plant (chr05_17842252 and chr08_14450306 for) while for Tuta absoluta resistance one SNP each i.e. chr05_10199243 for leaf damage and chr09_53321787 for total plant damage were common in different environments. The physical region in the candidate region of significant SNPs was inspected for putative candidate genes for each test trait. For morphological and biochemical traits, candidate genes were identified on six chromosomes i.e. chr04 (PGSC0003DMG400029501), chr05 (PGSC0003DMG401016322), chr06 (PGSC0003DMG400043458), chr08 (PGSC0003DMG400009402), chr09 (PGSC0003DMG400037214, PGSC0003DMG400040489) and chr12 (PGSC0003DMG402002888, PGSC0003DMG400042800) which encodes for specific functional groups or proteins. Besides, for Tuta absoluta resistance traits, candidate gene ‘PGSC0003DMG400018458’ were identified on chr05 involved in electron carrier and gene ‘PGSC0003DMG402001013’ present on chr09, encodes for DNA polymerase eta.y, correlation among tuber yield and its component traits, their direct and indirect effects on tuber yield, clustering pattern of genotypes, and genome-wide association studies for Tuta absoluta resistance and yield components in potato. The experimental material comprising of 357 potato genotypes including varieties, advanced breeding lines and exotic germplasm was evaluated in augmented block design for two consecutive years during the winter seasons of 2021-22 and 2022-23 at Nagrota Bagwan, Kangra, Himachal Pradesh. Data were recorded on average tuber yield per plant and 22 morphological and biochemical traits in addition to 5 entomological traits. Sufficient genetic variability was observed for yield and its related traits. Based on adjusted mean values, it was revealed that Kufri Garima, CP 3585, CP 1767, CP 2390 and CP 1989 were the superior/desirable performing genotype mainly due to the significant contribution of the number of tubers per plant and average tuber weight. High PCV and GCV were observed for the number of stems per hill, plant height, number of compound leaves per plant, number of tubers per plant, average tuber weight, average tuber yield per plant, total polyphenols and total carotenoids content irrespective of years. High heritability coupled with high genetic advance was observed for majority of traits during both the years indicating the importance of additive gene action for the inheritance of these traits. Correlation and path analysis revealed that the number of tubers per plant and average tuber weight in addition to tuber dry matter content could be advantageous for developing high-yielding genotypes. The cluster analysis revealed maximum inter-cluster distance between CP 3081 and JEX/A 683, JEX/A 19 and CP 3091, JEX/A 1081 and CP 4594 during 2021-22, 2022-23 and pooled over the years, respectively. GWAS analysis indicated significant marker-trait associations for different traits viz., tuber dry matter content, number of compound leaves per plant, plant height, non-reducing sugars, tuber width, leaf damage and total plant damage. Further it was observed that one SNP for plant height (chr04_3551782), two SNPs number of compound leaves per plant (chr05_17842252 and chr08_14450306 for) while for Tuta absoluta resistance one SNP each i.e. chr05_10199243 for leaf damage and chr09_53321787 for total plant damage were common in different environments. The physical region in the candidate region of significant SNPs was inspected for putative candidate genes for each test trait. For morphological and biochemical traits, candidate genes were identified on six chromosomes i.e. chr04 (PGSC0003DMG400029501), chr05 (PGSC0003DMG401016322), chr06 (PGSC0003DMG400043458), chr08 (PGSC0003DMG400009402), chr09 (PGSC0003DMG400037214, PGSC0003DMG400040489) and chr12 (PGSC0003DMG402002888, PGSC0003DMG400042800) which encodes for specific functional groups or proteins. Besides, for Tuta absoluta resistance traits, candidate gene ‘PGSC0003DMG400018458’ were identified on chr05 involved in electron carrier and gene ‘PGSC0003DMG402001013’ present on chr09, encodes for DNA polymerase eta.ThesisItem Open Access Management of Major Sucking Pests of Cowpea [Vigna unguiculata (L.) Walp](COLLEGE OF AGRICULTURE, BIKANER SWAMI KESHWANAND RAJASTHAN AGRICULTURAL UNIVERSITY, BIKANER, 2020) JAGMEET SINGH; H. L. DeshwalCowpea [Vigna unguiculata (L.) Walp] is a drought tolerant pulse crop belongs to the family fabaceae. It is believed to be originated in Cenral Africa, the largest producer. It is usually grown as Kharif crop, however, can be grown as a Rabi or spring summer crop in different parts of country. Cowpea is a multipurpose grain legumes, poor man’s source of protein and used as a pulse, vegetable as well as fodder crop in India. The young leaves and green pods are used as vegetables while several snacks and many meal dishes are prepared from the grain. All the plant parts that are used for food are nutritious. It comprises of over one hundred different type of species widely found in the tropical and sub tropical regions, and it has great morphological and ecological diversification (Quinn,1999; Paino D urzo, et al.1990).