VIEW ARTICLE

Disease Detection and Losses

Effect of Ratoon Stunting Disease on Yield of Sugarcane Grown in Multiple Three-Year Plantings. Michael P. Grisham, Research plant pathologist, U.S. Department of Agriculture, Agricultural Research Service (USDA-ARS), U.S. Sugarcane Research Unit, P.O. Box 470, Houma, LA 70361; Phytopathology 81:337-340. Accepted for publication 8 November 1990. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1991. DOI: 10.1094/Phyto-81-337.

Yield losses in sugarcane caused by ratoon stunting disease were observed for seven of eight cultivars tested in four to six crop cycles of 3-yr plantings. In the seven cultivars, average 3-yr losses ranged from 29 to 60 t/ha; sugar losses ranged from 2,627 to 7,369 kg/ha. Losses tended to increase with the number of years a planting was cropped. Cane losses averaged 14% in the first-year crop and increased to 27% in the third-year (second-ratoon) crop. For a given cultivar, the magnitude of losses varied among plantings; however, the planting × disease treatment interaction was not significant. Losses from ratoon stunting disease were observed for six cultivars that currently occupy approximately 93% of the sugarcane hectarage in Louisiana.