I

INVESTIGATOR: Bollich, P. K.

PERFORMING INSTITUTION:
RICE RESEARCH STATION
LOUISIANA STATE UNIVERSITY
BATON ROUGE, LOUISIANA 70893

ENHANCING RICE PRODUCTION WITH IMPROVED FERTILITY AND CULTURAL MANAGEMENT STRATEGIES

OBJECTIVES: Evaluate improved rice varieties and advanced experimental lines and develop agronomic production information for Louisiana; develop cultural management systems for use in conservation tillage rice production, with emphasis on plant population and nitrogen interactions; evaluate the effectiveness of slow-release nitrogen fertilizers in water- and dry-seeded rice culture and in conventional and conservation tillage systems; and determine the phosphorus and potassium requirements for main and ratoon crop rice.

APPROACH: Experiments will be conducted on- and off-station in Louisiana rice production areas. Statewide variety by N trials will generate agronomic information on new commercial varieties. This information will assist growers in variety selection and cultural management. Conservation tillage studies are also expected to provide grower information related to varieties, seeding rates, fertilization, and other cultural practices. A slow release urea material will be evaluated statewide to determine its potential for use in flooded rice systems. The benefits of such a product include reduced application costs, lower use rates, and increased efficiency. Phosphorus and potassium rate studies will be conducted on numerous soils statewide to assist in refining current recommendations and to identify soils where economical responses to their application might occur.

PROGRESS: 2001/01 TO 2001/12
Twenty commercial varieties and/or advanced experimental lines and two hybrids were evaluated statewide (five locations) in variety by nitrogen (N) trials. Francis (experimental line AR1081 from Arkansas) was released for commercial production for year 2002. It is a short stature long grain with good disease and lodging resistance and excellent yield potential. Three experimental lines developed in Louisiana for the Clearfield system are expected to be commercialized for production in 2002 also. Yield potential ranges from moderate to very good. Two hybrids developed by RiceTec Inc. displayed excellent yield potential, average milling quality, and very good lodging resistance. These hybrids, XL-7 and XL-8, are more agronomically suitable for Louisiana rice production than XL-6 previously evaluated. A N timing study was conducted statewide to compare single and two-way split N applications with five varieties. Overall, there was very little difference in grain yield across varieties and locations, indicating the effectiveness of each of these approaches. Variety by N trials conducted with a conventional tillage and stale seedbed comparison showed yields were similar. Paraquat and sodium chlorate were evaluated for their effectiveness as harvest desiccants on three rice varieties. Slight yield reductions in the ratoon crop have been observed, and milling yield in the main crop also has been decreased slightly with desiccant application. Paraquat is not labeled for use as a rice desiccant at this time, and the recommendation for sodium chlorate application has been changed. Application timing should be a 3- to 7-day preharvest period to minimize potential reductions in main crop milling yield and ratoon crop grain yields. Seeding rate evaluations with the varieties Cypress, Cocodrie, Earl, Wells, and Bengal indicated that 108 to 161 plants/m2 were required to optimize grain yields in both conventional and stale seedbeds when drill seeded.

IMPACT: 2001/01 TO 2001/12
Variety by N trials are essential in determining the rate of N required to optimize grain yield, minimize environmental concerns, and increase economic returns. Harvest desiccants improve harvest efficiency by desiccating the upper portion of the rice canopy; although, timing is critical to avoid reductions in head rice yield and ratoon crop yield losses. Optimum stand densities are important in maintaining optimum grain yields and minimizing disease problems associated with excessive stand densities. Additionally, higher seed costs are a reality with the new rice technology being developed, and seeding rates will be an important consideration.

PUBLICATIONS: 2001/01 TO 2001/12
1. Salassi, M.E. and Bollich, P.K. 2001. Less tillage, more $. Rice Journal 104 (3):14-15.
2. Bollich, P.K., Regan, R.P., Romero, G.R., and Walker, D.M. 2000. Ann. Res. Rpt., Rice Res. Stn., La. Agri. Exp. Stn., L.S.U. Agricultural Center, 92:88-151.
3. Bollich, P.K., Regan, R.P., Romero, G.R., Walker, D.M., Groth, D.E., Linscombe, S.D., Davis, W.E., and Grymes, III, J.M.. 2000. Louisiana rice variety trials 2000. LAES Research Summary No. 126. 81 pp.
4. Linscombe, S.D., Jodari, F., Bollich, P.K., Groth, D.E., White, L.M., Chu, Q.R., and Dunand, R.T. 2001. Registration of `Earl' Rice. Crop Science 41(6):2003-2004.

I

INVESTIGATOR: Bollich, P. K.; Leonard, B. R.; Drapcho, C.; Gaston, L.; Southern, L.

PERFORMING INSTITUTION:
ADMINISTRATION
LOUISIANA STATE UNIVERSITY
BATON ROUGE, LOUISIANA 70893

TILLAGE, SILVICULTURE AND WASTE MANAGEMENT

OBJECTIVES: 1. Develop cultural practices for producing rice using conservation tillage systems. 2. Determine cotton and corn insect control strategies to enable the use of conservation tillage systems. 3. Determine the contribution of dairy grazing systems to environment bacterial loading in surface waters. 4. Determine the environmental fate of poultry litter and develop beneficial uses including forest fertilization. 5. Determine phosphorus retention and movement rates in coastal plain soils. 6. Determine the effects of poultry diet modifications using phytase to reduce excreted phosphorus and ultimately reduce the amount moving into the environment.

APPROACH: Evaluate the effects of plant population, nitrogen fertilization, and water-seeded or drill-seeded systems on rice production. Evaluate soil insecticides for corn and management strategies for aphids and cutworms for cotton. Evaluate dairy management practices as they affect the quality of surface runoff from pastures and develop systems to differentiate between fecal and non-fecal origins of coliform in runoff. Determine the effects of poultry litter when used to fertilize pine trees and forage crops, measure the effects of poultry litter on pine tree growth, and determine the related effects on water quality. Determine the fate of phosphorus contained in poultry litter as it moves through soils, is absorbed by soils, or is discharged from amended soils. Evaluate poultry diet modification with phytase to determine the effect on pasture runoff water quality after litter has been applied to the landscape.

PROJ CONTACT:

Name: Brown, W. H.
Phone: 225-578-4181
Fax: 225-578-6032
Email: bbrown@agctr.lsu.edu