omparision Of Yield, Yield Components And Remobilization Of Assimilates In Old And New Rice Genotypes

This experiment was conducted to determine the most important effective component on grain yield of rice and share of assimilates، remobilization of each section of shoot organs on grain yield with 10 genotypes of rice on the base of randomized complete block design with 3 replications in Rice Research Institute (Amol-Mazandaran) in 1383-84. The genotypes included of 8 new lines and two cultivars، Fajr and Neda. Some criteria were studied such as 1000- grain weight، number of grains in punicule، number of punicules per area unit and number of grains per surface unit as yield components and share of assimilates remobilization of each shoot organs such as stem، flag leaf، other leaves and leaf area index at flowering stage. According to the results of variance analysis، rice genotypes had significant difference (P≥0. 01) in the point of all criteria except of grain weight and mature grain percent. Among genotypes، line 106 and line 104 had the highest and lowest grain yield، respectively. Line 106 in comparision to other genotypes had highest average of 1000- grain weight، number of punicules per area unit and number of grain in punicule. It had high percentage of mature grains، too. Also، high leaf area index at flowering stage in this line caused to increase remobilization during grain filling. The results of this research showed that 1000- grain weight and number of punicules per area unit have high correlation with yield. So، it is possible to use them to choose superior genotypes to improve grain yield.