Effect of withholding irrigation water after complete heading on rice yield and seed quality in mwea, Kirinyaga County-Kenya

Abstract

Rice is considered main source of calories and protein especially in many countries of Africa as it constitutes a major part of the diet. It is steadily becoming a major staple food for many households in Kenya as annual consumption has increased by 12 % for rice; compared with 4% for wheat and 1% for maize hence, increasing its productivity is paramount, as eating habits changes especially among the youth. Threat of climate change continues to impede agricultural activities, resulting to droughts and floods. Hence, the research investigated effect of withholding water after complete heading on morphological characters, yield and its components and seed quality attributes of rice at KARI Mwea and MIAD in 2012. Experimental layout was split plots in randomized complete block design (RCBD) where water was supplied intermittently, and withheld 10 days after complete heading, 15 days, and 20 days. Water withholding were the main plots. Four rice varieties which included Nerica-1, Nerica-4, Nerica-10 and Basmati-370 were selected for the study and used as sub plots. All agricultural agronomic practices were applied as recommended. Variables were scored from five mother (tagged) plants on panicle length, number of matured tillers, grain size, filled and unfilled grain per panicle, filled and unfilled grain weight per panicle, grain weight per five hills sample, 1,000 grain weight, filter and sand germination, seedling length and seedling vigor index. ANOVA was done using SAS program version 9.2. Results from the study indicate that there were no significant differences on the yield components when irrigation was withheld. There were significant differences (p<0.05) for morphological characters of varieties which indicated that the varieties were distinct from each other probably due to differences in the genotypes. Seed quality attributes were improved by withholding water. The results showed that water can be economized without affecting productivity and that quality of seed is affected when threshold level is interfered.