Effect of Inorganic Fertilizers and Farm Yard Manure on Agronomic Characteristics of Upland Rice Straw in Taita Taveta Highlands, Kenya

The study evaluated upland rice varietal agronomic characteristics and differences due to effects of fertilizer treatment and season at Taita Taveta University, Ngerenyi campus. The experiment was conducted during the short rains of 2018 and long rains of 2019. The experiment was a Randomized Complete Block Design with 3 replications. Individual plots measured 2.5 m by 2 m. Varieties evaluated were 17KH09010093B, WDR73 Hybrid, NERICA 1, NERICA 10 and Komboka. The treatments included were farm yard manure (8 tons ha-1), DAP at 75 kg ha-1, NPK (17:17:17) at 65 kg ha-1, and no fertilizer. Plant height, panicle length, leaf length, number of tillers, fresh weight, and dry weight were assessed. Variety, fertilizer and season had significant effects (P=0.05) on the morphological variables. NERICA 10 was the tallest variety at a mean of 72 cm in 2018 and a mean height of 61 cm in 2019. DAP treated plants were the tallest in both 2018 and 2019. Varieties were significantly different (P=0.0004) for panicle length. NERICA 10 had the longest panicles. Varietal effect was significant (P<0.001) for leaf length. NERICA 1 had the longest leaves in both seasons. DAP had the greatest effect on leaf length. Varieties differed significantly (P<0.001) in number of tillers per plant. Variety 17KH09010093B had the highest number of tillers per plant of 34.78 obtained in 2018. DAP resulted in the highest number of tillers. Variety and fertilizers interacted significantly (P=0.007) for foliage weight. WDR73 Hybrid out-yielded other varieties (149.31g) in fresh foliage weight. DAP resulted in the highest fresh morphological yield followed by NPK. There were significant differences in dry foliage weight among varieties and between seasons (P<0.001). Variety 17KH09010093B had the highest dry weight. Further studies on the socio–economics of fertilizer use should be conducted to provide reliable recommendations for upland rice production as forage.