Response of Paddy Rice (Oryza sativa L.) Morphological Characteristics to Nitrogen Fertilizers in Taveta, Kenya

This study investigated the effect of applying nitrogenous fertilizers on the morphological traits in six paddy rice varieties in Taveta, Kenya. The six paddy rice varieties, including local control, were tested during the 2018 and 2019 seasons. The experiments were laid out in a split-plot design with three replications. The main plot was the fertilizer treatment while the subplot was the varieties tested including NIBAM-11, K2-9, MWIR-2, R-1081, Silewa, and a local control Saro. The fertilizer treatments were no fertilizer, farm yard manure (FYM) alone, FYM+Urea fertilizer, and FYM+CAN fertilizer. Significant differences (P < 0.05) among varieties were observed for all the morphological traits that were assessed. Silewa was the tallest plant (111 cm), had the highest number of grains per panicle (163), and also the highest 1000-grain weight (29.2 g). Fertilizer treatments had significant effects on plant height, leaf length, number of tillers, panicle length, and number of grains per panicle. FYM+Urea resulted in the highest number of grains per panicle while FYM alone resulted in the highest 1000- grain weight (25.56 g). Varieties significantly interacted with fertilizers for the number of grains per panicle. Leaf length had significant direct association with 1000-grain weight (r = 0.427) and grains per panicle (r = 0.874). It can be recommended that there is an opportunity to use farm yard manure alone or in combination with an inorganic fertilizer to improve yield traits while reducing dependence on inorganic fertilizers.