Journal of Economic Entomology (2007) 100, 88-94

Charles F. Chilcutt and John E. Matocha (2007)
Effects of crop rotation, tillage, and fertilizer applications on sorghum head insects
Journal of Economic Entomology 100 (1), 88-94
Abstract: Rotations, tillage, and fertilizer treatments can affect yield, costs, and profitability in sorghum, Sorghum bicolor (L.) Moench, depending on their effects on pests. Rotation or planting different crops reduces soil erosion and pests that build up when a field is planted to the same crop each year. Minimum tillage reduces the number of trips over a field, lessening soil compaction and reducing costs. We examined the effects of fertilizer, tillage, and rotation with cotton, Gossypium hirsutum L., on sorghum head insects during three sampling periods each year from 2000 to 2003. We found that fertilizer treatments did not affect pests or predators. Also, predators were unaffected by rotation and tillage, which some years affected Helicoverpa zea (Boddie) and Oebalus pugnax (F.), both pests that feed on developing sorghum kernels, thereby reducing yield. In 2000, H. zea densities were greater in continuous sorghum, regardless of tillage practice, than in sorghum-cotton rotation. However, in 2003, H. zea densities were greater in minimum tillage plots within sorghum-cotton rotation than minimum tillage plots within continuous sorghum. In 2000, in sorghum-cotton rotation, O. pugnax densities were greater in minimum tillage than conventional tillage plots, whereas in continuous sorghum the opposite was true, O. pugnax were greater in conventional tillage. Also, O. pugnax were greater in sorghum-cotton rotation than in continuous sorghum. In 2002, O. pugnax densities were greater in conventional than minimum tillage plots. These results suggest that rotation of sorghum with cotton can sometimes reduce H. zea, but this reduction may occur with increased density of O. pugnax. Also, reducing tillage may reduce O. pugnax in some instances.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Charles F. Chilcutt

Research topic(s) for pests/diseases/weeds:
environment - cropping system/rotation

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Helicoverpa zea	Sorghum (crop)
	Oebalus pugnax	Sorghum (crop)