Study of assimilate remobilization as affected by heat stress in rice cultivars in north of Khuzestan
Subject Areas : agronomyAbdolali Gilani1 1 , Seyed Ataallah Siadat2 2 , Sami Jalali3 3 , Kaveh Limouchi4 4
1 - 1- Assistant Professor of Seed and Plant Improvement Research Department, Khozestan Agricultural and Natural Resources Research Center, AREEO, Ahvaz, Iran
2 - 2- Professor., University of Agricultural and Natural Resources of Ramin, Ahwaz, Iran
3 - 3- M.sc of Research Center of Seed and Plant Improvement Research Department, Khozestan Agricultural and Natural Resources Research Center, AREEO, Ahvaz, Iran
4 - 4- Ph.D Agronomy. Young Researchers and Elite Club, Dezful Branch, Islamic Azad University, Dezful, Iran
Keywords: current photosynthesis, organs portion, remobilization efficiency, sowing dates,
Abstract :
An experiment was carried out to study of heat stress on assimilate remobilization of rice in north of Khuzestan province in a split-plot arrangement using randomized complete blokes design with three replication in 2006 and 2007 at Shavoor Agricultural Research Station, Dependent in Research Center of Agricultural and Natural Resources of Khuzestan. For exposing rice cultivars to different higher temperature regimes, main plot were assigned to three sowing dates from 5 May, 26 May and 16 Jun and cultivars were; Hoveizeh, Hamar (heat tolerance) Ghermez Anbori, Champa (heat sensitive) and Danial (relatively heat tolerant) were in sub-plots. Results showed that the highest dry matter redistribution was in Ghermez Anbori and heat tolerant cultivars. The grain, stem and leaf portions were significant on sowing date and cultivars. The second and third planting dates and heat tolerant cultivars had higher content. The highest remobilization, current photosynthesis and the portion of organs in filling grain yield were 1140.8 kg.ha-1, 3923.3 kg.ha-1, and 22.5%, respectively, in 26 May planting. But the highest share portion of current photosynthesis in grain yield was in 5 may in the planting date.
_||_