Evaluation of F2 intergeneric population of papaya (Carica papaya L.) for resistance to papaya ringspot virus (PRSV)

- Attempts were made to evaluate the F2 intergeneric population of Carica papaya (var. Pusa Nanha, CP 50 and CO 7) and Vasconcellea cauliflora for PRSV resistance.
- Estimated the mean performance, genetic parameters in F2 population, mean and variability in F3 generation and reaction to the PRSV.
- Based on overall evaluation of F2 population, 18 progenies from Pusa Nanha × V. cauliflora, five progenies from CP 50 × V. cauliflora and one progeny from CO 7 × V. cauliflora were selected for further evaluation in F3 generation.

The present investigations were undertaken to evaluate the F2 intergeneric population of Carica papaya (var. Pusa Nanha, CP 50 and CO 7) and Vasconcellea cauliflora for PRSV resistance. Investigations were also made to estimate the mean performance, genetic parameters governing different traits and reaction to the PRSV in the F2 population. Among the crosses, Pusa Nanha × V. cauliflora recorded superior mean performance for fruit yield, number of fruits per tree and fruit biochemical parameters than other two crosses in F2 generation. Mean performance for papain recovery per fruit and the enzyme activity were high in CP 50 × V. cauliflora. Fruit quality parameters were high in CO 7 × V. cauliflora. Desirable mean performance for days taken for disease after inoculation and disease intensity score were recorded by Pusa Nanha × V. cauliflora. Among the various characters studied, higher GCV, PCV, heritability and genetic advance as percent of mean were registered by the cross Pusa Nanha × V. cauliflora for all the morphological characters and fruit yield parameters. From the F2 population 24 plus trees were selected for further evaluation based on their performance viz., morphological, yield, quality and biochemical characters and reaction to PRSV.