Tillage, Seeding, and Nitrogen Rate Effects on Rice Density, Yield, and Yield Components of Two Rice Cultivars

Harrell, D.L.; Blanche, S.B.

Agronomy Journal 102(2): 592-597


ISSN/ISBN: 0002-1962
DOI: 10.2134/agronj2009.0390
Accession: 066229656

Download citation:  

Article/Abstract emailed within 0-6 h
Payments are secure & encrypted
Powered by Stripe
Powered by PayPal

Research was conducted for 2 yr on a Crowley silt loam soil (fine, smectitic, thermic Typic Albaqualfs) near Crowley, LA to evaluate the main effects of tillage, seeding and N rate and potential interactions on rice (Oryza saliva L.) density, yield, and yield components. Two tillage systems (conventional and fall-stale seedbed), four seeding rates (162, 323, 484, and 646 seed m(-2)) and four N rates (101, 134, 168, and 202 kg ha(-1)) were evaluated. 'Jupiter' and 'Chenicre' a medium and long grain cultivar, respectively, were evaluated in separate experiments. Conventional tillage reduced rice plant density as compared with fall-stale seedbed tillage due to crusting following flush irrigation during seedling emergence. A tillage by N rate interaction was not observed, suggesting optimal N rates are similar for rice grown using a conventional or fall-stale seedbed. Rough rice grain yield was optimized at 202 and 168 kg N ha(-1) for Jupiter and Cheniere, respectively. Grain yields were optimized for Jupiter at 323 seed m(-2), while Cheniere required a seeding rate of more than 323 seed m(-2). Panicle density was found to be the single most influential yield component on rice yield and was able to explain 49 and 51% of the variation in yield for Jupiter and Cheniere, respectively. Filled grain panicle(-1) was inversely related to panicle density highlighting the ability of rice to tiller as a yield compensatory measure when less than optimum rice densities exist. However, total yield compensation may not be feasible at low seeding rates.