Sources of peanut bud necrosis disease resistance in groundnut with desirable yield parameters and pod features

Abstract

Groundnut (Arachis hypogea L.) is an important oilseed, food and fodder crop which is one of the five most important oil seed crops of the world. In India, groundnut is grown in an area of 5.47 million ha with a production of 5.51 million tones (2). Peanut bud necrosis disease (PBND) caused by peanut bud necrosis tospovirus (PBNV) vectored by Thrips palmi Karny (9) is a major disease of groundnut in South East Asia especially in India causing an yield loss of 89 million US dollars (1). The yield loss due to PBND in groundnut mainly depends on the time of infection. If the infection occurs on young plants (<60 days) pod yield loss will be 100% (6). On the basis of severity of PBNV incidence, a number of “hotspots” such as Mainpuri (Uttar pradesh), Rajendranagar,Kadiri and Palem (Andra Pradesh), Latur (Maharashtra),Tikamgarh (Madhya Pradesh) and Raichur (Karnataka) have been identified (3). Host plant resistance is an economical as well as desirable component in the management of viral diseases. Since, PBND is destructive disease, identification of genotypes that can resist/tolerate the disease during early stages of crop growth are useful in minimizing ield loss due to the disease. Although, some varieties are identified as resistant/tolerant to PBND but most of them do not have the desirable pod features. Screening procedures to identify groundnut genotypes with resistance to PBND have relied mainly on natural field infection (4). Since, Raichur is one of the ‘hot spots’ for PBNV infection in groundnut and the incidence of PBND can reach up to 75 per cent (5), it is suitable for screening of germplasm against the disease. Hence, during the present study 419 interspecific derivatives of groundnut obtained from Directorate of Groundnut Research (DGR), Junagadh were screened against the disease under natural epiphytotic condition and the resistant lines were evaluated for the pod features.