Effects of gamma ray on grain yield, yield components and morphological triats related to lodging in the rice of (Oryza sativa L.)

Gamma ray is one of the electromagnetic rays that has the capacity of ionization and inspiration and its penetrating power is more than that of beta and alphas. Therefore، To determine the effect of gamma ray on agronomic and morphological traits related to lodging in the rice (Oryza Sative L.) an experiment based on randomized complete block design (RCBD) was performed in four replications in the growth year of 1388 (2010) in the city of Qaemshahr. Treatments were rice seeds under different dozes of gamma rays (60 cobalt) in four levels (100،200 and 300 Gy and control or without shining). The results showed that the bending movement of third and fourth inter nodes with an increase in the gamma ray doze up to 300 Gy in comparison with the control 27. 4% and 28. 1%، respectively had a decreasing movement. The maximum grain yield with shining 300 Gy (259 gm2) was obtained. Because the highest number of spikelet in panicle (170. 15 ones) and number of panicle in a square meter (401. 25) was obtained for the same doze of shining. The lowest grain yield (173. 75 gm2) was obtained for the control group. The minimum plant height was obtained with shining 300 Gy that was equal to 145. 01centemeters and the maximum plant height was for the shining of 100 Gy and control respectively that was 153. 07 and 156. 56 centimeters.