Seed Health Management for Better Productivity - Govind Ballabh ...

(Seed Health Management for Better Productivity)Epidemiological Approaches to Disease Management through SeedTechnologyIntroduction(Mrs.) K. VishunavatDepartment of Plant Pathology, G.B.P.U.A.&T., Pantnagar-263145 (Uttarakhand)The quality of planted seeds has a critical influence on the ability of crops to becomeestablished and to realize their full potential of yield and value. A complex technology is required toensure high standards of seed quality that involves-Producing, harvesting, processing, storing andplating the seed.Throughout this process, careful handling to avoid mechanical injury and protection fromadverse environmental conditions, pests, and diseases are imperative. No one factor isnecessarily more important than another with respect to maintenance of seed quality but almost allseed crops require some measure of disease control. The knowledge of the epidemiology of seeddiseases can promote disease management through modern Seed technology.Disease impact on seed management systemsSeed Pathology emerged as a sub-discipline of plant pathology from analysis of seedquality in the early part of this century.Since than a world wide process of cataloguing microflorae of seeds have been associatedapproximately 2400 microorganisms with the seeds of 383 genera of plants. Concurrentlyepidemiological studies were carried out on the seed-borne phase of economically importantdiseases e.g. bacterial blight of beans, smuts of cereals and Stewart’s wilt of corn. There are threeenvironments in which seed exists:A. THE SEED PRODUCTION FIELDB. HARVESTING, PROCESSING AND STORING ANDC. THE PLANTED FIELDA. THE SEED PRODUCTION FIELDDisease can have an indirect effect on seed in the production field in that the seed is notassociated in any way with the pathogen but other plant parts are diseased; this renders the plantphysiologically ill equipped to complete the development and maturation of the seeds. Directeffects means that the seed itself is diseased, thus the viability and appearance of the seed isaffected and /or the pathogen is transmitted to the plant grown from the seed.(a). Seed infection in Seed production fieldSeed infection can occur during the three distinct physiological phases in the seed productionfield; anthesis, which covers the period from initiation of floral primordia to fertilization of theembryo; seed development, which represents the period during which the fruiting structures growand develop to full physiological maturity; and seed maturation, which is the dry down period thatcontinues until the seed is harvested.- 37 -