Incidence of Sugarcane Smut in Louisiana and Its Effect on Yield

Abstract

hectare. All cane stalks were cut by hand Hoy, J. W., Hollier, C. A., Fontenot, D. B., and Grelen, L. B. 1986. Incidence of sugarcane smut in at ground level, topped above the last Louisiana and its effect on yield. Plant Disease 70:59-60. hard stalk internode, and stripped of all leaf and leaf sheath material. Sugarcane (interspecific hybrids of Saccharum) infected by Ustilago scitaminea was observed in 13 The mean weight for smutfree stalks of 15 sugarcane-growing parishes in 1984. Frequency of observed infested fields and incidence of was estimated for the entire field in two diseased plants within fields were highest in susceptible cultivars CP 73-351 and NCo 310, wastimate for th entireieint intermediate in moderately susceptible cultivars CP 65-357 and CP 74-383, lowest in resistant plt-cantae fields(A and B)by determining cultivars CP 70-330 and CP 72-370, and absent in CP 70-321 and CP 72-356. Cane tonnage yields the mean stalk weight from five 15-stalk were negatively correlated (P= 0.01) with increasing levels of smut incidence observed in small samples collected at different locations plots in three plant-cane and one ratoon-cane field of CP 73-35 . The most significant effect of smut within the field. In the third plant-cane on yield was a reduction in number of healthy stalks in diseased plots, field (C) and the ratoon-cane field (D), a mean weight for smutfree stalks was determined for each individual plot from Smut, caused by Ustilago scitaminea within four commercial fields of CP 73- the total weight of the first 15 smutfree Syd., is an important disease of sugarcane 351 in which smut had spread naturally. stalks in each plot. (interspecific hybrids of Saccharum) that Stalk samples collected from individual has spread to all of the major cane- MATERIALS AND METHODS plots in fields C and D were milled, and growing areas of the world except Survey. A survey was conducted on 61 percent sucrose and fiber content