Integrated management of Papaya ringspot virus.

Papaya ringspot virus (PRSV) infection is a global threat to papaya (Carica papaya L.) cultivation. According to a survey conducted in western Maharashtra (India), about 32% of area under papaya cultivation was infected with PRSV. Farmers suffered about 20% yield losses when they failed to manage PRSV effectively. Based on trials at IARI, Regional Station, Pune and experience gained from farmers' fields, an integrated approach was developed to minimize losses due to PRSV infection. Since PRSV is transmitted mainly by aphid-vectors, avoiding and eliminating them is main theme of PRSV management. By transplanting papaya during the lean period of aphid-vectors population (spring season), PRSV infection was delayed till monsoon, by that time plants had crossed fruit bearing stage. PRSV infection till flowering was minimum on plants transplanted in early spring (18.25%), followed by mid (22.91%) and late (33.33%) spring. Border crop of banana reduced aphid population in papaya plantation from 31 to 18 aphids/trap. Papaya production increased marginally in the vicinity of uprooted infected plants. An integrated PRSV management is incorporation of above factors in various horticultural practices, such as selection of plantation season, raising border crop around papaya plantation, cultivar preference, use of virus-free seedlings, application of insecticides, regular weeding, and roguing of infected plants. Recent work on transgenic cultivars and their use as a parent in breeding programme is raising hope for development of PRSV resistant cultivars in near future. However, an integrated approach towards PRSV management can be the best option for successful cultivation of papaya under PRSV infected regimes till PRSV resistant cultivars are released.