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2019 - 201912020 - 20211
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Subject: Genetics and Plant Breeding × Author: Amit × Start date: 1997 ×
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    ThesisItemOpen Access
    Line x Tester analysis (fixed effect model) for yield and its components in fieldpea (Pisum sativum L.)
    (CCSHAU,HiSAR, 2021-08) Amit; Yadav, Rajesh
    Recombinant breeding is the most appropriate approach to combine various desirable attributes in self-pollinated crops. Genetic variability parameters, combining ability and heterosis were studied for days to flowering, maturity, primary and secondary branches per plant, nod per plant, height of first pod, plant height, pods per plant, seeds per pod, 100-seed weight, biological and seed yield per plant and harvest index in fieldpea (Pisum sativum L.) using line x tester design involving nine lines, three testers and their 27 crosses. The results revealed significant differences among the parents and hybrids for almost all the traits implying presence of adequate variability. Significant interaction between lines and testers was for almost all the traits expressed existence of sufficient amount of heterosis for most of the characters studied. Narrow differences between PCV and GCV of different traits indicated lesser influence of environment on the expression of these traits. Low heritability coupled with low genetic advance were observed for most of traits expect days to maturity, height of first pod and plant height suggesting that these traits are genetically controlled by non-additive gene action. The lines HFP 715 and Aman and the tester GP02/1108 and the crosses HFP 715 x GP02/1108, Aman x GP02/1108 and Pant P-243 x HFP 1426 were observed to be the best general and specific combiners, respectively for seed yield and its components. The σ2SCA >σ2GCA in almost all the traits indicating control of non-additive gene effects. High manifestation of heterobeltiosis for seed yield was evidenced by the superiority of 24 out of 27 crosses over better parent. High heterosis was observed in the cross HFP 715 x GP02/1108 followed by IPF 14-16 x GP02/1108, IPF 14-16 x HFP 1426, DDR-23 x HFP 1426, DDR-23 x GP02/1108 and Aman x GP02/1108 for yield and its attributes. The lines and crosses exhibited superiority in the present study can be exploited for isolating desirable transgressive segregants in advanced generations in future fieldpea improvement programmes.
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    ThesisItemOpen Access
    Studies on diversity for quality characters, cane yield and its contributing traits in sugarcane (Saccharum spp. complex) clones
    (CCSHAU, 2019) Amit; Ramesh Kumar
    Sugarcane (Saccharum species complex) is one of the important cash crop and playing a vital role in improving the economy of the country. It has unusual ability to store sucrose in stem cell vacuoles. In this study, 51 sugarcane genotypes were evaluated for morphological and quality characters in randomized block design (RBD) with two replications during 2018-19 at CCS Haryana agricultural university, regional research station, karnal. The sufficient genetic variability was observed from significant genotypic differences for all the 22 characters studied, indicated the appropriateness of the material selected. Phenotypic coefficient of variation (PCV) was higher than genotypic coefficient of variation (GCV) for all the characters representing more environmental impact on these characters for total variation. High heritability (broad sense) coupled with high genetic advance was observed for cane yield, commercial cane sugar (t/ha), germination % at 45 days after planting, number of millable canes at harvest, single cane weight, sucrose % at 8th month stage and commercial cane sugar % at 8th month stage. Therefore, it indicates that simple selection will be effective for these traits. Phenotypic correlation coefficients for cane yield showed significant and positive relationship with commercial cane sugar (t/ha), number of tillers at 120 days after planting, number of shoots at 240 days after planting, number of millable canes at harvest, single cane weight, stalk length, stalk diameter and brix % 10th at month stage. These traits play a greater role as an important contributing character for higher cane yield. The path coefficient analysis revealed that cane yield was shown by commercial cane sugar % at 10th month stage followed by commercial cane sugar (t/ha), sucrose % 12th at month stage, number of millable canes at harvest, single cane weight and stalk length had highest positive direct effect on cane yield. Therefore, in order to improve cane yield, effective selection can be accomplished for the characters having high direct effects. Based on D2 value, the clustering of 51 genotypes was carried out which resulted in 7 diverse clusters. The maximum inter-cluster distance (86.81) was observed between cluster II and cluster III. Bi-parental mating or poly-cross method involving genotypes belonging to cluster II (Co 7717, CoH 110, CoH 167, CoS 767 ) and cluster III (12-41, 11-703, 12-184, 12-263, 12- 493, 12-521, Co 89003) may be utilized in the hybridization programme as crossing between diverse parents is likely to produce wide genetic variability among the progenies.