|Namken, L - TX AGRIC EXP STN-WESLACO|
|Wolfenbarger, D - COOPERATOR|
Submitted to: Texas Agricultural Extension Service Regional Report
Publication Type: Experiment Station
Publication Acceptance Date: December 20, 1996
Publication Date: N/A
Interpretive Summary: The reniform nematode (Rotylenchulus reniformis) and the silverleaf whitefly (Bemisia argentifolii) are known pests to cotton (Gossypium hirsutum) producing areas of the Lower Rio Grande Valley of Texas. In 1995-1996, field studies were conducted at Weslaco, Texas, to determine and quantify the singular and combined effects of the reniform nematode and silverleaf whitefly on lint yield. Results indicated that reniform nematodes reduced total yield by 30%, while the silverleaf whitefly reduced yield by 22%. The most severe yield reduction by the silverleaf whitefly was observed in the second harvest. The severe effects on yield, especially the later maturing crop, demonstrate the importance of managing for an early crop, as well as the need to use cultural practices that reduce or avoid these pests.
Technical Abstract: Reniform nematodes (Rotylenchulus reniformis) are serious pests to cotton (Gossypium hirsutum) producing areas of the Lower Rio Grande Valley of Texas. In addition, the silverleaf whitefly (Bemisia argentifolii) can also cause severe damage. A two-year study was conducted in 1995-1996 to determine the singular and combined effects of these two pests on cotton at the USDA North Farm, Weslaco, Texas. Results showed that both pests are capable of causing severe yield losses. Across the two years, reniform nematodes reduced total yield by 29%, whereas whitefly infestations appeared to reduce yield by 22%. Whitefly damage was most observed in the second harvest, while reniform nematodes reduced both first and second harvest. The deleterious late season effects that the reniform nematode and silverleaf whitefly cause show the importance of managing the crop for early maturity.