A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development

Thesis (M.Sc.) - Asian Institute of Technology, 1985

In this study fungal invasion in paddy was characterized based on three method, namely, dilution plating, ergosterol assay and carbon dioxide production. Rewetted paddy samples having narrow moisture range of 13-14, 18-20 and 24-26 percent wet basis were stored at a room temperature of 30 +_ 10 ̕c and monitored for fungal growth for storage periods of 1,3,5,7, and 9 day. Paddy samples having 13-14 percent moisture content showed low fungal growth and consequently lower value of ergosterol and carbon dioxide production. Higher moisture content paddy samples were infected heavily by fungi within a short storage period indicating higher values of measured parameters such as fungal count, ergosterol content and carbon dioxide production. the fungal growth in high moisture paddy was suppressed by heat treatment. however, the heat treatment of paddy without cooling resulted in an uneven distribution of moisture causing vigorous fungal growth at the surface of the stored sample and damaging it rapidly. The logarithm of fungal count appeared to be highly correlated with either the ergosterol content of logarithm of carbon dioxide production. A third degree polynomial represented these relationships adequately, However, the relationship between fungal count and carbon dioxide production was observed to be more satisfactory based on overall considerations.