Forty Years of Papaya Research at Pusa, Bihar, India

Systematic research work on papaya was started during 1966-67 at Indian Agricultural Research Institute Regional Station, Pusa, Bihar, India with an objective to breed the varieties of uniform, high yielding with better quality for wider adaptability. Four varieties viz., Pusa Delicious, Pusa Majesty (Gynodioecious), Pusa Giant and Pusa Dwarf (Dioecious) were developed through continuous sibmating and selection by conventional breeding. Pusa Nanha (Mutant dwarf) was developed through mutation breeding by treating the seeds of papaya strain Pusa 1-15 with 15 Kr gamma rays. Comprehensive studies on sex inheritance in inter and intra-varietal crosses of papaya were attempted and a significant deviation of male and hermaphrodite from the expected ratio was observed. Genetic constitution of sex reversing male in papaya was established. Standardized the production technology of papaya in respect to planting density, time, nutrition and papaya based cropping system under North Bihar conditions. A marked reduction in viral infection was found by transplanting the papaya in month of October with heavy manurial doses. A new fungal disease "bud and fruit stalk rot of papaya" was discovered and standardized its control measure. Seed production of papaya under controlled pollination and isolation were done and found that seed produced under controlled pollination maintains maximum varietal purity with very high cost and less seed where as seed produced in isolation is more with low cost.