Occurrence of aflatoxins in cotton seeds at harvest in relation to location of growth and field temperatures

• Published in: Journal of environmental quality Vol. 2; no. 2; pp. 276 - 281
• Main Authors: Marsh, P.B, Simpson, M.E, Craig, G.O, Donoso, J, Ramey, H.H
• Format: Journal Article
• Language: English
• Published: American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America 01.04.1973
• Subjects: Aspergillus flavus; boll rot; fluorescence; free fatty acid; mycotoxin; temperature
• ISSN: 0047-2425; 1537-2537
• DOI: 10.2134/jeq1973.00472425000200020024x

Cotton seeds (Gossypium hirsutum L.) from 13 locations across the US Cotton Belt in 1969 and 11 locations in 1970 were analyzed for aflatoxins. Samples from most locations did not exhibit detectable aflatoxin contamination. However, aflatoxins B1 and B2 were found in one or more samples collected near Brawley, California; Phoenix, Arizona; and Weslaco, Texas, all in areas where a boll rot caused by Aspergillus flavus Link has been noted repeatedly since the crop of 1953. Aflatoxins occurred especially in seeds whose fiber exhibited a bright greenish yellow (BGY) fluorescence which is diagnostic for this boll rot. When seeds from the 1970 crop were examined for internal fungal infection, A. flavus was detected only in the seeds from Brawley. Free fatty acids were high in seeds from several areas, both with and without accompanying aflatoxins. Weather records indicated that A. flavus boll rot occurs mainly, perhaps exclusively, in conjunction with exceptionally high field temperatures.