Mycoflora, aflatoxins and free fatty acids in California cottonseed during 1967–1968

Abstract

In central California, neither fungal infections nor aflatoxins are significant problems in cottonseed during the receiving and storage seasons. However, in southern California, the 1967 harvest contained a relatively high percentage of seed which were invaded before harvest by fungi, includingAspergillus flavus. Seed infection and concentrations of aflatoxins in seed increased significantly during the time between harvest and storage in southern California. For a short time during storage, seed infection byA. flavus increased because of the moisture the seed received late in the season; however, aflatoxin concentrations in seed did not increase in storage. The aflatoxin content of the seed removed from storage was a reflection of the relative amount of aflatoxins the seed contained when they were received for storage. In 1967, the conditions that existed in the large, densely packed seed pile did not favor accummulation of aflatoxins in seed, even thoughA. flavus was active.

Fungi That Infect Cottonseeds Before Harvest

“…have been reported to cause infections in U.S.-produced cottonseeds (1,2,8,26, 27, R. B. Streets, A. M. Boyle, and H. Simonsen, Phytopathology 47:535, 1957); and A. flavus has been observed in seeds from the Imperial Valley of California (3,19). Seed infection with A. flavus has been noted in association with the characteristic BGY fluorescence in the fiber (19).…”

Field accumulation of aflatoxin in cottonseed as influenced by irrigation termination dates and pink bollworm infestation

“…Aflatoxins B1 and B2, produced by some members of the fungal groupAspergillus flavus Link, are common identifiable contaminants of cottonseed grown in the lower desert regions of central and southwestern Arizona, southwest Texas, and California (3,6). In these regions, bolls develop under summer time temperature highs which consistently exceed 35 C (6).…”