Survey and Molecular Identification of Begomovirus Associated with Chilli Leaf Curl Disease in Kurnool District of Andhra Pradesh

Abstract

Background: Chilli is an important spice and vegetable crop grown in tropical and sub-tropical climate. Recently, Chilli leaf curl disease has become a serious threat to chilli growing farmers. Methods: The present study was aimed to know prevalence of leaf curl disease in chilli. For this, roving field survey was carried out in 63 randomly selected chilli fields covering 21 villages in seven mandals of Kurnool district in Andhra Pradesh during 2019-20. Attempts were also made on molecular diagnosis of begomovirus associated with chilli leaf curl disease. Result: The average mean per cent incidence of chilli leaf curl virus in Kurnool district was 50.76% ranging from 25.0% to 82.2%. During the field survey, the highest mean leaf curl incidence was noticed in Peddakadubur mandal (71.1%) followed by Gonegandla (59.96%) and Nandavaram (52.27%) mandals, while the lowest leaf curl incidence was observed at Adoni (37.83%) mandal in Kurnool district. The amplified coat protein gene was sequenced and obtained 770bp sequence which was deposited in Gen Bank. The obtained sequence shared maximum identity of 99.7% with chilli leaf curl virus Guntur isolate (MN417112). As per species demarcation and nomenclature criteria of begomovirus, the virus associated with chilli leaf curl disease in Kurnool district shared greater than 94% sequence identity with Chilli leaf curl virus. Hence it was identified as chilli leaf curl virus (ChiLCV).