|Roof, M - CLEMSON UNIV.|
Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Abstract Only
Publication Acceptance Date: January 9, 2002
Publication Date: January 9, 2002
Citation: ROOF, M.E., BAUER, P.J. EFFECTS OF VARIETY, PLANTING DATE AND N LEVELS OF STINK-BUG INFESTATIONS IN COTTON. CD-ROM. NATIONAL COTTON COUNCIL BELTWIDE COTTON CONFERENCE. 2002. Technical Abstract: Stink bugs are now considered a major insect pest of cotton but little is known about factors that might influence their selection of cotton plants as hosts. This study provided an opportunity to measure damage caused by natural infestations of stink bugs to different cotton varieties, N levels and planting dates. Four different varieties (Dp 5415, Dp 5690, Dp 458B, and Dp 655B) were planted on 15 April, 1 May, and 15 May with N rates of 40, 80 and 120 lbs/acre in a split-split plot design. Collections of 25 quarter-sized bolls per plot were made on 3 August in 2000 and 31 July and 13 August in 2001. The majority of stink bugs found during the weekly field monitoring were green stink bugs, Acrosternum hilare. In 2000, the average boll damage rating of 6.3% was below Clemson's economic threshold of 15% and there were no significant differences between planting dates. Boll damage ratings were higher in 2001, averaging 13.7% on 31 July and 24% on 13 August. There was significantly less boll damage when collections were made on 31 July in 2001 from cotton planted 15 May (6.3%), than either 1 May (14.3%) or 15 April (20.7%). The same numerical trend for damage was shown in the 13 August collection, but differences were not significant. In 2001, damage ratings exceeded 15% in the majority of plots on 31 July, and by 13 August, the 15 April planting sustained 27% damage. There were no significant differences in stink bug damaged bolls between varieties or N levels in 2000, or on either sampling date in 2001.