الفهرس | Only 14 pages are availabe for public view |
Abstract The objective of this study was designed to investigate the effect of seed priming with different concentrations of growth bioregulators (i.e. indole acetic acid, gibberellic acid or kinetin) on growth and metabolism as well as productivity of Vigna sinensis L. Cream 7 plants throughout various stages of plant growth and development. Also, particular interest was focused on the effect of these growth bioregulators on the biochemical and physiological aspects of yielded seeds of Vigna sinensis plants. In general, the results of this study showed that, indole acetic acid, gibberellic acid or kinetin at different concentrations stimulated the growth vigor of cowpea plants (root length, root fresh and dry weights shoot length, shoot fresh and dry weights and leaf area production) allover growth periods. Although seed pretreatment with IAA or kinetin induced significant increases in total leaf conductivity and transpiration rate that was accompanied by decrease in R.W.C.; GA3 induced opposite results in these parameters. In the majority of cases seed priming with different concentrations of different growth regulators increased photosynthetic pigments, photosynthetic characteristics, Hill activity as well as carbohydrate content in leaves of cowpea plants. It is clear from this investigation that seed presoaking in different concentrations of IAA, GA3 or kinetin improved yield and yield quality of cowpea plants by inducing a massive increase in seed biomass, pod length, number of pods/plant, number of seeds/pod as well as increased protein content, total soluble sugars, sucrose, polysaccharide level and endogenous growth stimulators (auxins, gibberellins and cytokinins). On the other hand these growth bioregulators induced massive decrease in growth inhibitors equivalent to abscisic acid in the yielded seeds of cowpea plant. Also, it is evident from this study that kinetin application appeared to be the most effective hormone in improving growth and productivity of cowpea plants. |