Microbial damage to raw cotton, sometimes referred to as weathering damage, is a common event in most parts of the world. Microbes, viz. bacteria and fungi, are omnipresent in the environment. In the case of cotton production, microbes form an essential part of the biology and health of the soil in which the cotton plants grow. After the opening of the boll, wind-blown dust and soil components are deposited on the cotton fibres, carrying with them various bacteria and fungi. Thus the microorganisms are always present and only require favourable conditions for their growth. Ideal conditions occur when rain delays the harvest.