Cytological Study of Anthers for Pollen Sterility in the F7 Generation of a Rice (Oryza sativa L.) Cross

The present research work was proficiently done at the experimental plot of Birsa Agricultural University, Kanke under the rainfed conditions of Jharkhand, India during kharif 2021. The F7 generation seeds of the cross Pusa-1176 x BPT-5204 was sown as panicle to progeny rows in the seed bed nursery and thereafter transplanted into the field. In this investigation, the study has been oriented more towards the male sterility as it is more sensitive than female gametes based on the observation recorded in previous generation (F6) regarding spikelet sterility percentage. Henceforth, the study has been focussed on the microscopic study of pollen grains to validate the reason behind the cause of spikelet sterility in the panicles. To understand this phenomenon, pollen viability test was done by staining the anthers with 1% Iodine- potassium iodide in order to know the extent of fertility or sterility present in the pollen grains of the rice segregants. Through microscopic study, segregation was observed in the pollen sterility % among the families studied which might be due to the change in the environmental conditions such as temperature, photoperiod and humidity etc. The expected genetic ratio obtained was 9:3:3:1(partially sterile+highly fertile/completely fertile/ highly sterile/completely sterile) revealing that it is controlled by 2 genes since the ratio fitted in digenic ratio.