The Impact of Some Growth Regulators on Growth and Productivity of Faba bean Plant Grown under Newly Reclaimed Soil Conditions

Abstract

Two field experiments were conducted during two winter successive seasons 2019/2020 and 2020/2021 at the National Research Station, Area, Egypt. The purpose of the study was to investigate the link between vegetative development, yield, yield components, and numerous metabolic variables components of the "Giza 716" Egyptian faba bean cultivar (Vicia faba L.) to foliar application of three growth regulators; paclobutrazol (PBZ; 30, 60 and 90 ppm), mepiquat chloride (MC; 500, 1000 and 1500 ppm) and baritone (AGR; 400, 600 and 800 ppm). The foliar application of PBZ, MC, and AGR had positive effects on all growth and yield parameters. On the other hand, the three growth regulators reduced plant height, fresh and dry weights of branches and leaves/plant, fourth leaf area and leaf area index, specific leaf weight, crop growth rate, net assimilation rate, relative growth rate, and yield (number of pods per plant, number of seeds per pod, pod weight/plant, seed and straw yield/plant, seed and straw yield/feddan, seed index), and harvest index), when used in high concentrations. By boosting total carbs, crude protein, total free amino acids, nitrogen, phosphate, and potassium, PBZ, MC, and AGR considerably boosted total photosynthetic pigments content in leaves and improved seed quality and nutritional value. Generally, foliar application of PBZ, MC, and AGR When used at low quantities, it had a favorable impact on growth parameters, photosynthetic pigments, seed yield and yield components, as well as several biochemical components of the faba bean seeds yield. net assimilation rate (NAR), and relative growth rate (RGR), as compared with untreated control plants, highly significant. Data also show the most effectiveness treatments were AGR at 400 and 600 ppm followed by PBZ at 30 ppm for all growth parameters. Foliar application of PBZ up to 60 ppm, significantly increased the area of fourth leaf (4 th LA), leaf area index (LAI), specific leaf weight (SLW), crop growth rate (CGR), net assimilation rate (NAR), and relative growth rate (RGR) compared with relevant untreated control units. compared control plants.