Tuesday, November 14, 2006 - 11:15 AM

Extending New Technologies for Nitrogen Management in Corn Production.

Roger Teal1, Robert Woods2, Kyle Freeman2, Brian Arnall2, Clinton Mack2, and William Raun2. (1) Univ of Georgia, 2608 Northfield Road, Tifton, GA 31793, (2) Oklahoma State Univ, 230 W. Okmulgee, Suite C, Muskogee, OK 74401

Fuel and fertilizer costs have risen drastically and commodity prices mirror those from half a century ago.  As a result, great opportunity exists for increased farmer cooperation to develop more sustainable production practices. Recent research has shown that nitrogen use efficiency (NUE) can be improved by 10% in corn (Zea mays L.) using in-season yield potential prediction and N response determination. As an effort to extend this technology, trials were implemented on nine farmers’ fields across Northeast and Central Oklahoma in the spring of 2005. The trials were designed in a randomized complete block design (RCBD) with four replications. Treatments consisted of: a check (0 N), farmer’s practice (N rate of farmer’s choice), N rich (336 kg ha-1), and in-season N determination (84 kg ha-1 preplant followed by sidedress N determined at eight leaf stage). At the time of sidedress N rate determination, the farmers were present to demonstrate how the new technology worked in their fields. The in-season N rate determination was superior to the farmers’ N management practices overall with a 50 $ ha-1 gain in gross return as a result of a 36% reduction in total N applied. In addition, at two locations, sidedress N applications were withheld since no detection of response to preplant N was evaluated using the in-season N determination method. In February of 2006, three producer meetings were held at sites strategically located near the field trials where the results of the data was presented and discussed. As a result of this out-reach program, greater interest has been shown in adopting the technology with high attendance at a two-day training seminar held for county extension agents and producers alike to use this technology.