Effect of Mycorrhiza on Growth, Biochemical Constituents and Yield of Snap Bean Plants under Water Deficit Conditions
A field experiment was carried out during two successive growing seasons of 2013 and 2014, at The Experimental Farm, Faculty of Agriculture, Ain Shams University, Shoubra El-Kheima, Egypt. The aim of this study was to investigate the effect of mycorrhiza on vegetative growth and yield productivity of snap bean (Phaseolus vulgaris L.) under water deficit conditions. Results indicated that irrigation at 60 or 45 % of water holding capacity reduce all vegetative growth parameters such as plant height, branches number per plant, shoot fresh weight and shoot dry weight in both seasons as compared with irrigation at 75% of water holding capacity. Mycorrhiza gave a significant effect on enhancing growth vegetative characteristics, so its effect was clearly significant increment on snap bean yield. For the biochemical constituents, mycorrhiza increased total sugars, total protein, N, P, K, Mg, Ca, Fe, Zn, Mn and Cu concentrations in snap bean leaves under all irrigation treatments as compared to non mycorrhizal plants in both seasons. In contrast, mycorrhiza reduced proline concentration in snap bean leaves as compared to non mycorrhizal plants in both seasons. Mycorrhiza increased number of pods per plant, pod weight, pod length and pod yield per plant under all water treatments in the two tested seasons. Generally, the interaction between irrigation at 75 % of water holding capacity with mycorrhiza gave the highest values for all growth parameters, yield traits and biochemical constituents except the highest concentration of proline which resulted when snap bean irrigated at 45 % of water holding capacity without mycorrhiza in both seasons.