Effect of Foliar Nutrition of Chelate and Nanofertilizers of Iron and Zinc on Growth and Yield of Mung bean (Vigna radiata L.)

Micronutrient elements play a key role in the formation of chlorophyll and function of photosynthesis, respiration, enzyme system and physiological processes of the plant and their deficiency has destructive effects on the growth, production and yield of the plant. This research was conducted in a factorial experiment based on a randomized complete block design with three replications on mung bean plant in the Research Farm of Bu-Ali Sina University, Hamedan, Iran, in 2019-2020 growing season. Two cultivars of Gohar and Partu and foliar spraying of zinc chelate, iron chelate, zinc nano-fertilizer, iron nano-fertilizer, and control (spraying solution with water) were tested. The maximum leaf area index (3.12), maximum growth rate (16.2 g m-2 day-1), and leaf area duration (157 day) were achieved by Gohar cultivar in the presence of foliar application of zinc nano fertilizer. Zinc nano-fertilizer had the greatest effect on the pods/plant (21.7), grains/pod (8.08), and grains/plant (164) of Gohar cultivar, which increased by 62, 22 and 62, 77.6 percent respectively, compared to the control. The highest biological yield (8599 kg ha-1) was obtained with Gohar cultivar when receiving foliar application of iron nanofertilizer and zinc nanofertilizer. The highest grain yield (2657kg ha-1) was obtained with Gohar cultivar subjected to nano-zinc foliar spraying, which was not significantly different from Parto cultivar in foliar spraying with zinc nano-fertilizer and caused 38% and 35% increases in grain yield of the two cultivars compared to the control, respectively. The highest harvest index was also obtained with Gohar cultivar supplemented by foliar spraying of zinc nano fertilizer, which increased the harvest index by 24% compared to the control. Foliar spraying of iron and zinc fertilizers caused significant increases in growth, biological yield and grain yield, as well as the content of these elements in the grain of both cultivars. The effect of zinc and iron nanofertilizers on the studied traits was more pronounced in Gohar variety than in Parto variety.