Radical changes in crop production have occurred in the southeastern USA in recent years. Peanut (Arachis hypogaea L.) and cotton (Gossypium hirsutum L.) are now planted in direct rotation, and conservation tillage is commonly used for both crops. Comprehensive data is lacking on crop and pest management recommendations in those systems, so a long‐term study was conducted in Tifton, GA on the effects of tillage systems on crop and pest management in a peanut–cotton rotation. Systems evaluated were conventional, reduced, and minimum tillage. Plots in conventional tillage systems were harrowed, deep‐turned, and planted each year. In reduced tillage systems, plots were harrowed in the fall and planted to rye (Secale cereale L.), and crops were planted into killed rye. In minimum tillage systems, plots were neither tilled nor planted to rye and remained nontilled during the winter, and crops were planted directly into the previous crop stubble. Weed control was based on species present and tillage system. Peanut was either treated with flutolanil [3′‐isopropoxy‐2‐(trifluoromethyl) benzanilide] for soil‐borne disease control or not treated (control). Yields were sustained for 5 yr with no difference in peanut or cotton yields among tillage systems. Flutolanil controlled soil‐borne diseases and increased peanut yields, working equally well in all three tillage systems. Weed densities and species composition changed, causing more intensive and costly weed control in reduced and minimum tillage systems than in conventional tillage systems. Spotted wilt (tomato spotted wilt tospovirus) incidence was 42% lower in reduced and minimum tillage systems than in conventional tillage systems and is now part of the recommended strategy to manage the disease.

Theoretically, cotton planted in narrow rows at high plant populations has a potential of reducing production cost by promoting earlier maturity. The cost of controlling insects, weeds, and harvest due to a once‐over harvest would all be reduced. Studies were conducted to determine how a cultivar developed for conventional production methods would respond to a narrow row system. Coker 310 was planted in conventional 91.4 cm rows at a population of 107,489 plants/ha, in four 40.6 cm rows on a 182.9 cm bed and in twin 25.4 cm rows on a 91.4 cm bed at populations of 214,977; 286,636; and 358,295 plants/ha for 3 years. There were no differences in yield, earliness, lint percent, fiber length or strength between narrow row and the conventional check. The conventional check produced larger bolls, fewer blooms, a lower potential yield and set a higher percent of early blooms. Narrow rows gave no differences in total yield, earliness, lint percent, fiber length, or strength resulting from row patterns or plant populations. The highest plant population gave more blooms in twin 25.4 cm rows, but not in 40.6 cm rows. Potential yield was not influenced by population within row patterns, but there was a row pattern response at the same plant population. Boll size tended to be inversely related to plant population. The highest plant population in the 40.6 cm rows produced a finer fiber than other treatments. This study indicates the potential of high population — narrow row planting is lost mainly through excessive shedding of young bolls during the first 3 weeks of blooming.

The effect of crop rotation (main plots) and pesticide treatment (subplots) on stem rot (Sclerotium rolfsii), Meloidogyne arenaria, and the nematode antagonist Pasteuria penetrans was determined in a field experiment. The field site was naturally infested with all three organisms. Peanut (P) was rotated with 2 years of either cotton (Ct), corn (C), or bahiagrass (B). The pesticide treatments for the peanut crop were aldicarb (31 g a.i. per 100-m row), flutolanil (1.7 kg a.i./ha), aldicarb + flutolanil, and a control without either pesticide. Populations of M. arenaria were lower in peanut in the Ct-Ct-P than in P-P-P, C-C-P, or B-B-P plots and tended to be lower in plots treated with aldicarb. Abundance of P. penetrans endospores was highest in the P-P-P plots, intermediate in the B-B-P rotations, lowest in all other rotations, and was unaffected by aldicarb. The high endospore densities in the P-P-P plots may have contributed to the uncharacteristically low nematode populations in the monoculture. Incidence of stem rot in peanut was lowest in treatments with flutolanil, intermediate in the control, and highest in treatments with aldicarb alone. The greater canopy cover in aldicarb-treated plots may have created a conducive environment for S. rolfsii infection.

Moths of the soybean looper (SBL), Pseudoplusia includens (Walker), were released into 1.8 × 3.7 m field cages (10 male:female moth pairs/cage) containing nectaried (floral and extrafloral nectaries) or nectariless (no extrafloral nectaries) cotton cultivars. Cages containing moths were left undisturbed for 7 days, at the end of which time, plants within cages were sampled for SBL eggs. In three separate tests conducted in 1982, 1983, and 1984, moths oviposited significantly more eggs/plant in caged nectaried cotton than in caged nectariless cotton. High larval SBL populations in cotton-soybean agroecosystems are attributed to SBL moth utilization of cotton nectars to increase fertility and fecundity prior to oviposition in nearby soybean fields. Thus, use of nectariless cotton cultivars may reduce SBL pest populations on soybean by decreasing the amount of cotton nectar available.