Sugarcane Aphid Spatial Distribution in Grain Sorghum Fields

Abstract

Abstract. Sorghum, Sorghum bicolor (L.) Moench, is an important summer grain crop in the United States. In 2014, the U.S. produced 432 million bushels of sorghum valued at $1.67 billion on more than 2.43 million ha. The sugarcane aphid, Melanaphis sacchari (Zehntner), was discovered in damaging numbers in grain sorghum in Texas and Louisiana in 2013. The sugarcane aphid can be very damaging to sorghum grown for grain and forage and is capable of explosive population growth. An objective sampling plan based on knowledge of spatial distribution of the aphid in sorghum would be useful for pest management decision making. We sampled 94 commercial grain sorghum fields in five southern states during 2 years to obtain data that were used to assess several aspects of sugarcane aphid distribution within and among sorghum plants in commercial grain sorghum fields. There were frequently significant differences in number of aphids among upper and lower leaves in fields in each state. However, there were no consistent...