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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]