Prevalence and development of storage fungi in peanut Arachis hypogaea seed

Summary A batch of peanutArachis hypogaea seed were divided into 4 2-kilogram portions and stored 6 months at 22–28° C. One portion was stored with the moisture content slowly increasing from 4 to 28 %; the other portions were maintained at approximately 4.5, 8.9 and 11.5 %. After 1, 2, 3, 4, and 6 months storage, 100 seed of each treatment were cultured on malt-10 % NaCl agar and the fungi isolated identified. The storage fungi present after intervals of storage were compared with those initially present. In seed stored at 4.4 % moisture,Aspergillus species remained about the same andPenicillium decreased. At 8.9 % moistureA. flavus, A. repens andPenicillium were reduced, andA. amstelodami andA. ruber increased. At 11.5 % moisture, 100% of the seed yieldedA. ruber after 4 months storage and the other storage fungi decreased to 0–2 %. The moisture content of seed stored at 99 % R. H. increased slowly to 28 % and resulted in monthly changes in the dominant fungi. Under such a circumstance with competition between these storage fungi,A. ruber grew best at 12–15 %,A. repens at 18.5 %,A. flavus andPenicillium at 20 %, andA. amstelodami between 20–28 %.Fusarium increased very rapidly as moisture content increased above 18 %.This investigation was supported by Agricultural Research Service, U.S. Department of Agriculture, Contract No. 12-14-100-8179 (34), administered by the Crops Research Division, Beltsville, Maryland.Former Research Associate, North Carolina State University, Raleigh, N. C., currently Research Plant Pathologist, Market Quality Research Division, Agricultural Research Service, United States Department of Agriculture; and Professor, North Carolina State University, Raleigh, N.C.Paper number 2489 of the Journal Series of the North Carolina State University Agricultural Experiment Station, Raleigh, North Carolina.