Investigating the Effect of Amendments of Zeolite, Superabsorbent Polymer, and Different Amounts of Irrigation on Sesame Yield

In order to investigate the effect of soil amendments, zeolite and superabsorbent polymer, on the quantity and quality of sesame yield under drought stress, a factorial experiment was performed in randomized complete block design with three replications, at Research Field of College of Agriculture, University of Birjand, in 2017-2018. Treatments included irrigation at two levels of 50% and 100% water requirement and amendment materials at 6 levels of Z0, Z1, Z2, Z3, Z4 and Z5. (Z0= Control, Z1=adsorbent polymer (125 kg / ha), Z2 = 11.2 ton/ hect of zeolite and Z3 =6.2 ton/hect of zeolite, Z4= zeolite 11.2 ton / hect of zeolite + 125 kg / hect of adsorbent polymer, Z5 =6.2 ton/ hect of zeolite + 125 kg /hect/ of adsorbent polymer) In this study, 1000-grain weight, percentage of crude grain oil, crude protein of grain, plant height, grain yield, harvest index, and water use efficiency were investigated. The results showed that 1000-grain weight, oil percentage, grain protein, plant height, and sesame grain yield were affected by different levels of irrigation and amendments at 1% probability level. Also, harvest index and water use efficiency were affected by different levels of amendments at 1% probability level. Oil percentage, grain yield and harvest index were affected by interaction effects of irrigation levels and amendments at 1% probability level. The highest grain weight, percentage of crude grain oil, crude protein of grain, plant height, grain yield, harvest index, and water use efficiency were observed in Z4 treatment. The results showed that the change in irrigation level from 100% to 50% significantly reduced yield. The highest amount of 1000-grain weight in different levels of amendments was 4.12 g in Z4 and the lowest was 2.89 g. in Z0 treatments Also, the highest amount of crude grain oil in irrigation and different levels of amendments was 56.8% and 40.5%, respectively. The highest and the lowest amount of crude protein in response to different levels of amendments were 15.7% and 13.1%, respectively. The results showed that drought stress had a negative effect on plant growth, but the use of zeolite and superabsorbent polymer partially offset this effect.