Identification of Rice Varieties/Cultures Resistant to Virulent Gall Midge Biotype 4 for North Coastal Districts of Andhra Pradesh

A special research programme, to find out the causes of outbreak of virulent gall midge that devastated GMR varieties Phalguna and Surekha during 1986 Kharif and to identify and popularize alternative resistant varieties, was organized on the pest stricken farmers’ fields of Srikakulam district in North coastal Andhra Pradesh through 1987–1991. Susceptible reaction of crop grown from breeder's seed of Phalguna and Surekha, which showed resistance upto year 1985, confirmed that the outbreak was due to development of a new virulent biotype different from previously identified biotypes 1, 2 and 3. Of eighteen advanced genetic lines resistant in the field screening during 1987 and 1988 to gall midge populations of Srikakulam, 14 were derived form Velluthacheera resistant donor, 2 each from Orumundakan and Ptb 10. As a result of on-farm verification cum demonstrations from 1988 to 1990 and compact block demonstrations, farming community picked up the resistant varieties - Suraksha, Abhaya and IET10831 for cultivation to encounter new biotype and realized high yields.