Physical Sciences and Mathematics Commons^™

Starter Nitrogen Source And Preflood Nitrogen Rate Effects On Rice Grown On Clay Soils, Linda Rachelle Martin

Graduate Theses and Dissertations

Seedling rice (Oryza sativa L.) grown on clayey-textured soils generally develops slowly as compared to loamy-textured soils. Our research examined the effects of starter-N source and preflood-N rates on canopy closure, total aboveground N uptake, and grain yield of rice grown on clayey-textured soils. Eleven field trials were established in Arkansas and Mississippi including five trials with a hybrid cultivar and six trials using a pure-line cultivar. Starter-N sources included no starter-N (NONE), ammonium sulfate (AMS), diammonium phosphate (DAP), and urea (UREA) applied at 24 kg N ha-1 at the rice 2-leaf stage and five preflood-N rates ranging from 0-224 …