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The insidious flower bug, Orius insidiosus (Say), is reported to effectively suppress Frankliniella species thrips populations. The objective of this study was to determine the effectiveness of this predator in reducing thrips populations in cotton (Gossypium hirsutum L.). Population fluctuations of the predator and thrips on the leaves, squares, and flowers were tracked on plots in Quincy and Marianna, FL, in 2006 and 2007, and weekly predator-to-prey ratios were used to assess the effectiveness of the predator in regulating the thrips populations. The bulk (> 95%) of the Frankliniella thrips were found in flowers and F. tritici (Fitch) constituted > 98% of the adult thrips population. Other thrips recorded were F. occidentalis (Pergande) and F. bispinosa (Morgan). The highest and lowest weekly predator-prey ratios in the flowers in Quincy were 1:5 and 1:1170, and 1:92 and 1:1900 in Marianna. No correlation was observed between O. insidiosus and thrips abundance. Results of this study indicate that O. insidiosus may not be an effective predator of F. tritici in field cotton during the reproductive stage. [ABSTRACT FROM AUTHOR]

Cotton (Gosspium hirsutum L.) growth and yield following a white lupin (Lupinus albus L.) grain crop may be influenced by tillage system and rate of N fertilizer application. Field studies were conducted on Dothan sandy loam from 1995 through 1997 to evaluate the influence of conventional (CT) and strip-tillage (ST) systems in combination with four rates (0,67,134, and 202 kg N ha-1) of sidedress N on growth, development, and yield of 'Deltapine 5409' cotton following a white lupin grain crop. The 202 kg N ha-1 rate was split into two applications so that 134 kg ha-1 was applied 4 wks after planting and 68 kg ha-1 was applied 7 wks after planting. There were significant year by tillage by N rate interactions for lint yield, plant height, bolls plant', and bolls meter-2, and significant tillage by N rate interactions for boll weight and lint weight boll'. Because of higher bolls m-2, lint yields were greater from cotton grown under ST than CT. For every 1 kg N ha-1 applied to cotton, lint yield increased by 2.49 kg ha' under ST in 1995, 1.07 and 1.69 kg ha-1 under CT and ST, respectively, in 1996, and 1.81 kg ha-1 for CT in 1997. Based on regression analysis, maximum lint yields were achieved with the application of 76 kg N ha-1 under CT in 1995, and 78 kg N ha' under ST in 1997. Plant height, bolls plant-1, and bolls m-2, and boll weight increased with increasing N rates. Lint yields were primarily correlated with bolls m-2. Following a white lupin grain crop, cotton can be successfully grown in ST. Nitrogen application to cotton increased lint yields due to increased bolls m-2. The optimal N rate for cotton following white lupin was 78 kg N ha-1. [ABSTRACT FROM AUTHOR]

In 2001 and 2002, a field study was conducted in Quincy, FL, with glyphosate-resistant cotton (Gossypium hirsutuni L.) to evaluate the influ- ence tillage on weed control, plant development, and yield. Two tillage systems, conventional and strip-till, were evaluated. The plots were broadcast sprayed with glyphosate (Roundup Ultra; Monsanto, St. Louis, MO) at 427 g a.i. ha-1 when cotton plants were at the 3- to 5-node stage and direct-sprayed at the same rate at the 8- to 10- and the 12- to 15-node stages. Averaged across years, tillage system did not influence cot- ton yields (957 and 964 kg ha-1 for conventional and strip tillage, respectively). For most traits, responses were not affected by tillage or by the tillage by year interaction. Greater weed control was obtained for conventional than strip-tilled cotton (1.3 and 4.1% of the soil surface covered with weeds, respectively) at 30 days after treatment (DAT), but weed control at 10 and 60 DAT was similar between treatments. Plant stand at 14 days after planting (DAP) was greater in conventional tillage in 2002. Plants were taller in conventional tillage at 90 DAP in 2002, but number of main stem nodes were greater in strip tillage at 90 and 120 DAP in 2002. Strip tillage increased the total number of bolls per plant, and the number of bolls on the second and third position of the fruiting branch in 2002. These results indicate that growing cotton in strip-tillage is comparable to conventional tillage. [ABSTRACT FROM AUTHOR]