Effect of BAP, ethrel and stem gtrdling on growth and partitioning of photosynthates in Y-shaped mungbean

During early vegetative growth, pots grown mungbean (Vigna radiata (L) Wilczek cv, Pusa 105) were forced to develop a Y-shaped stem consisting of two symmetrical branches. At preflowering stage, the plants were treated with 6-Benzyl amino purine (BAP-20 ppm) and elhrel (500 ppm). Stem girdling was also done just below the junction of the two symmetrical branches and hormonal application (BAP) was done on one of the branches and its effect was observed in other branch of the same plant. Suitable controls were kept.

BAP delayed the leaf senescence, enhanced photosynthetic rate and its duration on the treated as well as untreated leaf, whereas ethrel enhanced leaf senescence, reduced photosynthetic rate and its duration. ¹⁴C studies indicated that the translocation of photosyntnates was diverted differentially to other plant parts through hormonal application. Girdling on main stem affected the remote effects of hormones and about 98% ¹⁴C remained on the applied branch itself indicating that growth regulators showed their effect on the other branch through roots only.