ENHANCEMENT OF GUAR GROWTH AND PRODUCTIVITY BY BradyrhizobiumINOCULATION UNDER DIFFERENT NPK FERTILIZATION LEVELS

Abstract

Two field experiments were carried out during the two consecutive summer seasons of 2019 and 2020 at Experimental Farm (Ghazala Farm) of Agric. Fac., Zagazig Univ., Egypt. This study was to try to enhance the growth and yield of guar plant. The experiment was set up as split-plot design between NPK fertilization as main plot and bio-fertilization as sub-plot. The NPK fertilization levels were (0.0, 75, 100 and 125% of recommended level), while, the Bradyrhizobium inoculation rates were (0.0, 200 and 400 g/feddan). The NPK fertilization recommended rate (RR) was Ammonium sulfate (20.5% N) at 200 kg/feddan, calcium super phosphate (15.5% P 2 O 5 ) at 200 kg/feddan and potassium sulfate (48% K 2 O) at 100 kg/feddan. The obtained results revealed that fertilized guar plants with 125% RR significantly increased plant growth (plant height, number of leaves and branches/ plant, fresh and dry weights of branches, leaves and roots/plant and root length), yield components (pods number per plant and seed yield per plant and per feddan) as well as total carbohydrates content compared to control and the other levels under study. Moreover, the highest Bradyrhizobium inoculation rate (400 g/feddan) significantly recorded the highest values of all abovementioned parameters compared to control and lowest one. Predominantly, the results of this study showed that fertilized guar plants with 125% RR of NPK fertilization could help to enhance growth and productivity of guar (Cyamopsis tetragolnoloba Taub.) plant combined with 400 g/feddan of Bradyrhizobium inoculation rate under Sharkia Governorate conditions.