Larry G. Heatherly

Arthropod populations in early soybean production systems in the mid-South.

Abstract We compared the severity of insect problems in early and conventional soybean, Glycine max (L.) Merrill, production systems in the mid-South. The conventional soybean production system (cultivars in maturity groups V–VII planted in May) experienced significantly higher populations of late-season defoliators than the early soybean production system (cultivars in maturity group IV planted in April). However, the early soybean production system harbored significantly larger populations of southern green stink bug, Nezara viridula (L.) and threecornered alfalfa hopper, Spissistilus festinus (Say). Predators were significantly more abundant in the early soybean production system compared with the conventional soybean production system, early in the growing season. Late in the growing season, predator populations were lower in both productions systems and differences between the two systems were not significant. The results from the current study illustrated the benefits of early-planted early-maturing cultivars (early soybean production system) in avoiding lepidopterous and coleopterous defoliators that occur late in the growing season. However, our data also indicate that arthropod management will be essential in the early soybean production system because widespread use of this system will result in an abundance of suitable hosts for early-season pests.

Yield and economics of traditional and early soybean production system (ESPS) seedings in the midsouthern United States

Abstract Drought stress reduces yield of traditional May and June seedlings of soybean in midsouthern USA. Field experiments using Maturity Group (MG) IV and MG V soybean cultivars were conducted at Stoneville, Mississippi (latitude 33°26′ N) for five years to determine effects of earlier-than-normal (April) and normal (May) seeding on net returns from soybean grown with, and without, irrigation. Net returns were calculated as the difference between income and all direct and indirect costs excluding those for land, management, and general farm overhead. In the irrigated environment, average net returns from April seedings of MG IV cultivars were greater than those from May seedings in all years, while average net returns from April seedings of MG V cultivars were greater than those from May seedings in all years except 1997. These greater net returns resulted from larger seed yields, lower estimated costs, higher prices received for harvested seed, or a combination of the three. Average net returns from April seedings ranged from US

Influence of early-season nitrogen and weed management on irrigated and nonirrigated glyphosate-resistant and susceptible soybean

148 to US

Effects of storage environment and duration on impermeable seed coat in soybean

617/ha, while average net returns from May seedings ranged from US

Midsouthern USA Soybean Yield Affected by Maturity Group and Planting Date

69 to US

Managing Inputs for Peak Production

567/ha. Use of MG IV vs. MG V cultivars had no consistent effect on net returns from either April or May seedings. In the nonirrigated environment, average net returns from April seedings of all cultivars were greater than those from May seedings in all years. Average annual net returns from cultivars seeded in April ranged from US

Influence of Large Amounts of Nitrogen on Nonirrigated and Irrigated Soybean

74 to US

Drought stress and irrigation effects on germination of harvested soybean seed

374/ha, while average annual net returns from May seedings ranged from US

Soybean Cultivars' Response to Flood Irrigation of Clay Soil

−9 to US

Yield and Germinability of Seed from Irrigated and Nonirrigated Early- and Late-Planted MG IV and V Soybean

325/ha. In three of the five years, MG V cultivars sown in April produced more yield and greater net return than did MG IV cultivars, while April-sown MG IV cultivars produced the highest yield and net return in one of the five years in the nonirrigated study. These results indicate that earlier-than-normal (April) seedings of either MG IV or MG V soybean cultivars will result in increased net return vs. that attained from traditional (May or later) seedings in the midsouthern USA. These results also indicate that choosing cultivars within an MG is more critical than choosing between MG IV and V.