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A study was carried out at Cotton Research Institute, AARI, Faisalabad Pakistan during the year 2013 to determine the cause and effect of some morphological traits viz. number of leaves per plant, number of sympodial branches per plant, number of bolls per plant and plant height on seed yield per plant in upland cotton. Seventy two cotton genotypes at F5 generation were sown in a RCBD with three replications. The results indicated that number of leaves (0.2334), sympodial branches (0.4859) and number of bolls per plant (0.3722) had exerted positive and significant to highly significant correlation at genotypic level with seed cotton yield per plant. The data also revealed that number of leaves showed positive and highly significant correlation with sympodial branches (0.3427"") plant height (0.6924"") and bolls per plant (0.4238""). Number of leaves, bolls per plant and sympodial branches showed positive direct effect on seed-cotton yield per plant. Direct effect of sympodial branches on cotton yield was very high and positive. However, number of leaves showed positive indirect effect via sympodial branches, bolls per plant and plant height. Similarly sympodial branches had shown positive indirect effect on seed yield per plant via number of leaves and bolls per plant. Direct effect of number of leaves on seed-cotton yield per plant was low while indirect effect via number of bolls per plant was positive. The number of bolls per plant also showed positive indirect effect via number of leaves, sympodial branches and plant height but effect of plant height on cotton yield was negative via number of bolls and sympodial branches. The results conclude that sympodial branches per plant influenced the cotton yield per plant to greater extent. Hence selection based on this trait may lead to development of genotypes having high seed cotton yield potential. [ABSTRACT FROM AUTHOR]

Present study was conducted during 2011-12 in COMSAT Institute of Information Technology, Abbottabad, Pakistan. Two parent genotypes diploid wheat's (A-genome donor) along with their 48 recombinant in bred lines (RILs) at F7 were evaluated for estimating components of variance, phenotypic and genotypic coefficients, heritability and genetic advance for seed yield and its components. Experiment was laid out in RCBD with three replications. Highly significant differences were observed for all the characters. Phenotypic coefficients of variation (PCV) estimates were found higher than genotypic coefficients of variation (GCV) estimates for all the studied characters in all genotypes showing the influence of environment on traits. A very small difference between GCV and PCV was observed for the traits of plant height, peduncle length and spike length showing less influence of environmental factors on these characters. Large difference between GCV and PCV was observed for the number of tillers per plant, total biomass, spikelets per spike, 1000-grain weight and grain yield per plant. This specified the role of environmental influence on these characters. High heritability (0.579bs) coupled with high genetic advance (6.983%) was observed for 1000-grain weight signifying that this character was under the control of additive genetic effects. The results suggested that selection on the basis of this trait would certainly useful for the breeding program. [ABSTRACT FROM AUTHOR]

Genetic potential of 20 cotton (Gossypium hirsutum L.) varieties was evaluated against different levels of salinity stress under green house conditions in the Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad during 2011-12. Plants were grown in polythene bags in CRD with three replications. Four NaCl concentrations (0, 100, 150 and 200 mM) were applied to the genotypes after one week of emergence of seedlings. Data on root length, shoot length, root fresh weight, shoot fresh weight, root dry weight, shoot dry weight and fresh seedling weight were recorded. The results clearly indicated varying growth potential of seedlings of all varieties under low and high saline conditions. Based upon absolute data, varieties NIAB-78, MNH-554, and CIM-448 proved to be more tolerant than MS-94, RH-112 and MNH-147. Estimates of broad sense heritability appeared to be high under low and high salinity suggesting that salinity tolerance in cotton genetically controlled. Superiority in salt tolerance of NIAB-78, MNH-554 and CIM-448 may be attributed to low uptake of Na+ and greater K+/Na+ ratio. [ABSTRACT FROM AUTHOR]

The present study was carried out to estimate genotypic and phenotypic correlation coefficients to create a path for the improvement in yield of linseed (Linum usitatissimum L). For this purpose nine linseed accessions (LS-1, LS- 15, LS-16, LS-20, LS-27, LS-29, LS-35, LS-40, LS-48) and a check variety Chandani were tested at Department of Plant Breeding and Genetics, PMAS, Arid Agriculture University, Rawalpindi, Pakistan during 2011-12. The experiment was laid out in RCBD. Genotypic correlation estimates showed that seed yield of a plant is positively affected by primary branches, number of capsules per plant, number of seeds in each capsule, thousand seed weight and oil content while days to flower initiation, number of days to complete flowering and number of days to physiological maturity has a negative impact on seed yield of plant. Phenotypic correlation estimate results showed the similar findings except the thousand seed weight which has a significantly positive effect on seed yield. Estimates of the genotypic correlation coefficients were further used to determine the path coefficient of analysis by partitioning the correlation into indirect and direct effects. Path coefficient analysis depicted that the number of capsules per plant (0.432), oil content (0.194%), number of primary branches of each plant (0.196), thousand seed weight (0.100 g) and number of seeds in each capsule (0.116) had a direct influence on seed yield in positive direction. This predicted that while designing a breeding strategy for the improvement of linseed a trait should be kept in mind to enhance seed yield in linseed. Therefore focusing on these traits, would improve breeding efficiency of linseed in the future breeding programs. [ABSTRACT FROM AUTHOR]

Present study was conducted on 9 advanced linseed genotypes (LS-9, LS-10, LS-21, LS-22, LS-23, LS-37, LS-38, LS-39, LS-42 (Linum usitatissimum L.) and a check variety Chandni for genetic evaluation at NARC, Islamabad, Pakistan under Oilseeds Research Programme. These genotypes were sown in RCBD with three replications during rabi 2011-12 at research area. At maturity stage data of ten different yield and its related parameters were recorded. Genetic variability, heritability and genetic advance indicated that genotypic mean squares were highly significant for all the traits. Phenotypic variance was greater than genotypic variance that indicates influence of environment on the traits under study. Heritability estimate values ranged from 0.51% for oil content to 0.99% for days to flower initiation. Heritability estimates for different characters were found maximum (0.99) for days to flower initiation followed by days to maturity (0.96), 1000 seed weight (0.96), seed yield/plot (0.94) and days to flower completion (0.92). High heritability estimates indicated that improvement could be made through selection. Maximum relative expected genetic advance was recorded for seed yield/plot (22.75%) followed by number of primary branches/plant (20.10%). Genetic advance as percent of mean was calculated highest (22.75) for seed yield/plot followed by number of primary branches/plant (20.10) and number of capsules/plant (17.39). [ABSTRACT FROM AUTHOR]