Effect of Zn of the panicle structure and yield of coarse rice. ir-6

The study was carried out to evaluate the effect of four zinc levels on the growth and yield of coarse rice cv IR-6 at Faisalabad, Pakistan during 1991. All the four zinc levels viz. 2.5, 5.0, 7.5 and 10 kg ZnSO/sub 4/ha caused increase in yield and yield component of IR-6 as compared with control. Final plant height, number of tillers/hill, panicle bearing tillers, number of primary and secondary spikelets: panicle size, 1000-grain weight, paddy and straw yield and harvest index showed positive correlation with the increase in ZnSO/sub 4/ levels from 2.5 to 10 kg/ha. However sterility percentage decreased as the level of ZnSO/sub 4/ increased. All the yield components exhibited significant increase, except harvest index, thought, had increased but not significantly indicating that a still higher level of zinc may be required to obtain a significant difference or otherwise. It is concluded that not only Basmati rice, but the coarse rice like IR-6 is also affected by various levels of zinc for growth and yield of rice. (author)