Abstract

                                In no phase of agriculture there is greater need for careful planning than in the maintenance of the purity of the improved strains of crops dur- ing the course of their multiplication and distribution. It is more so in the case of crops which are mainly cross-fertilized. The criterion of the methods adopted should be such as to combine minimum cost with efficiency in ensuring against cross-fertilization with other varieties. Otherwise, costly methods of selfing followed in the seed nucleus plots would soar to a staggering amount when adopted for large scale seed farms. Lack of cheap and suitable methods for protecting the purity of the crop have all along proved a sericus handicap for the rapid spread of high yielding cumbu strains in the black soils of the Tinnevelly District.

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