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

We compared the severity of insect problems in early and conventional soybe an, Glycine max (L.) Merrill, production systems in the mid-South. The conv entional soybean production system (cultivars in maturity groups V-VII plan ted in May) experienced significantly higher populations of late-season def oliators than the early soybean production system (cultivars in maturity gr oup IV planted in April). However, the early soybean production system harb ored significantly larger populations of southern green stink bug, Nezara v iridula (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 t he growing season. Late in the growing season, predator populations were lo wer in both productions systems and differences between the two systems wer e not significant. The results from the current study illustrated the benef its of early-planted early-maturing cultivars (early soybean production sys tem) in avoiding lepidopterous and coleopterous defoliators that occur late in the growing season. However, our data also indicate that arthropod mana gement will be essential in the early soybean production system because wid espread use of this system will result in an abundance of suitable hosts fo r early-season pests.