The Effect of Different Planting Dates on the Anatomy of the Flag Leaf and Grain Yield of Rice Varieties in the Khuzestan Region, Iran

This study aims at investigating the effect of different planting dates (change of ambient temperature conditions) on the flag leaf anatomy and function in rice and a village located 70 km north of Ahvaz, Khuzestan, Iran. A split plot experiment was used based on randomized complete block design with three replications. The main factor was in the three levels of planting date (25 May, 9 June, and 25 June) and the second factor was in three levels including Red Anbori varieties (long and short) and Champa. Analysis of variance showed that in all characteristics there is a significant difference between the impact of different planting dates and numbers at 1% level and there is a significant difference between these two factor interactions in the surface characteristics of wood and xylem bundles drain at 5% and 1% levels respectively. The highest and lowest yields and levels of large vascular bundles, small, wood and phloem belonged respectively to the first and third planting dates. Grain yield had the most significant positive correlation with the level of the small vessel (0.905**), the timber vessel (0.810**) and phloem (0.428*) which indicates a direct high impact of these characteristics on increasing the performance and also reveals the need for further remedial investigation so as to improve the performance. Among figures, the highest one belonged to the performance of Champa with the average 3795.4 kg per hectare. Number of large (on the 1 length mm) and small (on the 5 length mm) vascular bundles and buliform cells (on the 5 length mm) were not affected by planting date and were identical in all figures.