Kaolin reflectant treatments have been shown to reduce stress due to the environment, pests, and pathogens in many plants. We tested the effect of kaolin on yield, beet curly top virus (BCTV) incidence, and physiological parameters (measured as hyperspectral reflectance) of field-grown chile pepper (Capsicum annuum L.) in southern New Mexico. Curly top incidence was significantly lower in kaolin-treated chile blocks than untreated blocks. Peppers treated with the kaolin-reflectant showed significantly less water stress and higher photochemical reflectance than untreated plants during active growth periods. Treated plants had significantly higher levels of chlorophyll a and higher reflectance than untreated plants. Yield from treated plants was not significantly different from that from untreated plants. We did not detect any deleterious effects on peppers due to application of kaolin. Kaolin treatments suppressed beet curly top virus on chile and reduced water stress parameters during the hottest months of the growing season, suggesting that it would be useful in New Mexico chile production in years with moderate disease pressure.
Rebecca Creamer, Soumaila Sanogo, Osama A. El-Sebai, Jared Carpenter, and Robert Sanderson
Robert F. Bevacqua and Dawn M. VanLeeuwen
Chile pepper (Capsicum annuum L.) yields are highly variable and are strongly influenced by disease and weather. The goal of two field experiments was to evaluate crop management factors, especially planting date, that could contribute to improved and more consistent crop production. Current practice in New Mexico is to direct seed the crop from 13 to 27 Mar. In the first experiment, chile pepper was direct seeded on three planting dates, 13, 20, and 27 Mar. 2000, without or with a fungicide treatment of pentachloronitrobenzene and mefenoxam for the control of damping off. The results indicate planting date had no effect on stand establishment or yield. Fungicide treatment, significantly reduced stand, but had no effect on yield. In the second experiment, chile pepper was direct seeded on six planting dates, 13, 20, 27 Mar. and 3, 10, 17, Apr. 2001, with or without an application of phosphorus fertilizer, P at 29.4 kg·ha-1, banded beneath the seed row. During the growing season, this experimental planting suffered, as did commercial plantings in New Mexico, from high mortality and stunting due to beet curly top virus, a disease transmitted by the beet leafhopper. The results indicate planting date had a significant effect on crop performance. The best stand establishment and highest yield were associated with the earliest planting date, 13 Mar. This date also resulted in the least viral disease damage. Phosphorus fertilizer had no effect on stand establishment or yield. Chemical names used: pentachloronitrobenzene (PCNB); (R)-2-[(2,6-dimethylphenyl)-methoxyacetylamino]-propionic acid methyl ester (mefenoxam).
Paul W. Bosland
During a natural field epidemic of curly top virus, accessions within five species of Capsicum were evaluated for resistance. Accessions were considered resistant if 0% to 25% of the individual plants were devoid of curly top virus symptoms. Resistance was found in three accessions each of C. annuum L. and C. frutescens L. and one accession each of C. chacoense Hunz. and C. chinense Jacq. The resistant C. annuum accessions were `Burpee Chiltepin', `NuMex Bailey Piquin', and `NuMex Twilight', while the C. frutescens resistant accessions were USDA-Grif 9322 from Costa Rica, PI 241675 from Ecuador and `Tabasco'. The resistant C. chacoense accession was PI 273419 from Argentina and the C. chinense resistant accession was USDA-Grif 9303 from Colombia.
Brian A. Kahn and John P. Damicone
disease problem is beet curly top virus (BCTV), a curtovirus that is transmitted by the beet leafhopper ( Circulifer tenellus ). Beet curly top virus typically is a sporadic disease of Oklahoma tomato crops; but in 2003, a devastating outbreak caused
Paul W. Bosland and Carl A. Strausbaugh
Curtovirus species: Beet curly top virus (BCTV; formerly Cal/Logan strain), Beet severe curly top virus (BSCTV; formerly CFH strain), and Beet mild curly top virus (BMCTV; formerly Worland strain). In the United States, cayenne pepper ( Capsicum annuum L
Mark E. Uchanski and Adam Blalock
immediately after harvest, separated, and weighed separately. Cayenne pods infected with Beet curly top virus or other disorders without tissue or pod necrosis were considered marketable. Red pod percentage was calculated as red pod fresh yield divided by
Bielinski M. Santos, Teresa P. Salame-Donoso, and Alicia J. Whidden
. 2005 Kaolin-based foliar reflectant affects physiology and incidence of beet curly top virus but not yield of chili pepper HortScience 40 574 576 Glenn, D.M. Prado, E. Erez, A. McFerson, J. Puterka, G.J. 2002 A reflective, processed-kaolin particle film