Assessment of the role of growth reduction factors on some morpho-physiological and yield indicators of rice (Oryza sativa L.) cultivars in climate condition of Khuzestan

In order to Assessment of the role of growth reduction factors on some morpho-physiological and yield indicators of rice cultivars an experiment in the year 2018 was conducted as split plot in a randomized complete block design with three replications. Experimentation factors included various rice varieties: Champa, Chermez-anbori and Hoveizeh in the main plot and reducing growth factors include: control (without cutting), consumption of half a liter of medax top in 45 days after planting, cut 65 days after planting to a height of 35 cm and cut 85 days after planting at a height of 35 cm in the subplot was. the results showed difference between levels of reducing growth factors in terms of stem height, panicle number, number of hollow seed per panicle and seed yield were at 1% probability and 1000-seed weight at 5% level. the difference between cultivars in terms of number of hollow seed per panicle at 1% level and 1000 grain weight at 5% probability level. highest number of hollow seed per panicle was in the control and the lowest in the cut 65 days after planting. the highest grain yield was obtained in the application of medax top with average of 4.7 tons/h and the lowest grain yield with average of 3.19 tons/h was obtained by cutting in 85 days after planting. so it can be cut by 65 days after the planting and use of the medax top or using the hoveizeh cultivar to reach the desired results in the region.