Investig ation of sink - source relations in different planting systems rice (Oryza Sativa L.) Fajr cultivar

Inorder to investijation the effect of source and sink relationship and the planting systems in the rice of Fajr cultivar, an experiment performed in the rice investigations institute of researches center in Amol at 2010. This experiment performed as split plot with 3 replication. Different planting system including three levels (traditional planting, improved planting and SRI planting) were cutting in main plots and 3 levels of sink- source relations (omitting)1/3 panicle, omitting flag leaf and control in flowering) were allocated in sub plots. maximum grain yield(873/9 gram at m2) produced under system of improved planting. Grain yield has significant increasing in the improved planting compared to traditional and or SRI planting to 18/3% and 25/1 % respectively; because maximum and minimum number of empty spikelet in the panicle obtained respectively for SRI and improved planting systems. Minimum number of empty spikelet in the per panicle producedin cutting of 1/3 panicle that has significant decrease in comparision to control at 39/5 ratio that showing limitation of photo synthesis source in the fair cultivar. Number of empty spikelet at ten panical obtained by cutting of flag leaf have increased about 7/3% compared with control that showing importance of filled in spikelet the flag leaf. Grain yield decreased about 16/4% by cutting flag leaf compared to control. Treatment Intraction effect of different planting systems with source- sink relations was significant only on the number of empty spikelet on panicle, statistically 5 percent.