Abstract

In plantations, various diseases may affect the outplanted seedlings right from the beginning, till the time of harvest. Thr rotation period of most of the SF crops depends and decided on the basis of tree species as well as local demand and end use. Since, the same species are raised under different biogeoclimatic conditions throughout the country, a species which is highly susceptible to a particular pathogen in certain climatic zone may prove to be resistant in other due to unfavourable edaphic and climatic conditions prevailing. Similarly, disease which becomes progressive and spread to an epidemic proportion in an extensive monoculture plantation may appear insignificant and less hazarduous in small block or strip plantations of the same species under the same climatic conditions and vice versa. Thus, occurrence, spread and severity of disease and host responses may vary and a less important disease in a particular area may become devastating in other. Hence, it is