Influence of Variety, Seedling Transplanting Age and Nitrogen Fertilizer Rates on Selected Chemical Composition of Rice Grains and Straws

Abstract

The study was conducted under lowland ecological conditions at the Edozhigi and Badeggi National Cereal Research Institute (NCRI) farms in the Guinea savannah region of southern Nigeria during the 2015 and 2016 growing seasons. The objective was to determine the effect of seedling transplanting age and nitrogen fertilizer rates on nutrient content of two rice varieties. The trial was laid out in a split-split plot arrangement fitted into randomized complete block design (RBCD) and replicated three times. The treatments for the trial consisted of two rice varieties as the main factor (FARO 44 and FARO 52), the sub plot factor consisted of four seedling transplanting ages (7, 14, 21 and 28) and the sub-sub plot factor consisted of five inorganic N fertilizer rates (0, 60, 120, 180 and 240 kg N/ha). Rice grains and straw after harvest were analyzed for N, P, K, Fe and Zn content. The result of the rice grain and straw nutrient content revealed a significant effect of location on rice grain nitrogen and zinc content. Rice planted at Edozhigi gave significantly higher nitrogen and zinc content in rice grains in 2015 and 2016 planting seasons. Nitrogen fertilizer application had significant effect on rice grain nitrogen content in 2016 planting season. The result showed a significant (p<0.05) effect of variety on Zn content of rice grains. Rice variety Faro 44 produced significantly higher rice grain zinc content of 0.334 and 0.297 ppm during both planting seasons. Significantly (p<0.05) rice variety Faro 44 had higher rice straw nitrogen content of 0.172 and 0.165% in 2015 and 2016 planting seasons respectively. In conclusion, the application of 240 kg N/ha to 14 and 28 days old of Faro 44 rice variety revealed more nutrient content in rice grain and straw.