M. D. Jasani, J. H. Kamdar, A. K. Maurya and S. K. Bera QTL MAPPING FOR RESISTANCE TO PEANUT BUD NECROSIS DISEASE (PBND) IN PEANUT (Arachis hypogaea L.) M. D. Jasani, J. H. Kamdar, A. K. Maurya and S. K. Bera ICAR-Directorate of Groundnut Research, Junagadh, Gujarat.

Peanut Peanut is an economically important oilseed crop cultivated in an area of ~25.44 m ha, with a production of ~45.22 m tons Peanut is a valuable source of edible oil (48–50%) and protein (26–28%) for human beings and fodder for livestock India alone produces ~ 20% (9.47 m tons) of total peanut production in the world Gujarat ranked first in area and production and produces more then 50% of total peanut production in India

Peanut Bud Necrosis Disease PBND is caused by Peanut bud necrosis virus (PBNV), vectored by Thrips palmi Karny PBND has emerged as a serious yield constraint of peanut especially in South Asia and in parts of China, Nepal, Sri Lanka and Thailand It can cause yield losses up to 70-80% in peanut and many other crops Thus, it is very important to identify markers linked to PBND resistance for widening the genetic base of cultivated peanut.

Symptoms of PBND Infected

Methodology Plant Material JL 24 : susceptible to PBND NRCGCS 85 : resistant to PBND Hybridization and generation advancement 108 RILs were derived from cross between JL 24 x NRCGCS 85 by selfing of F1 seeds Phenotyping and genotyping Phenotyping of RILs - UAS, Raichur, Karnataka Genotyping of RILs - polymorphic SSRs markers Linkage and QTL mapping Genetic linkage groups and QTL mapping were constructed using the statistical software QTL IciMapping V4.1

Result Phenotyping Phenotyping of 108 RILs with both parents was done under natural field conditions in the field of UAS, Raichur, Karnataka during Rabi 2017. Frequency distribution for PBND incidence

Genotyping A total of 1980 SSRs were used in polymorphism survey, 227 (11.46%) SSRs were found polymorphic Among them only 49 SSRs found co-dominant which were further used in linkage analysis and QTL mapping

Linkage mapping A genetic linkage map comprising of 47 SSRs on 8 linkage groups with total genome distance of 977.42 cM. The longest linkage group was LG6 (201.61cM) and shortest was LG5 (20.27cM).

Linkage map prepared using 47 SSRs in peanut

Single marker Analysis QTL mapping Single marker Analysis

Composite Interval mapping Two major QTLs were identified for resistance to PBND on linkage group six and seven. QTLPBND-01 is flanked by IPAHM 509 and AHS0006 and QTLPBND-02 is flanked by TC4G10 and TC9C08. LOD score and phenotypic variation ranged from 3.13 to 3.62 and 12.38 to 16.88, respectively. Trait QTL name Linkage Group Position (cM) Marker interval LOD PVE (%) Additive effect PBND QTLPBND-01 6 29.00 IPAHM509- AHS0006 3.62 16.88 2.90 QTLPBND-02 7 80.00 TC4G10- TC9C08 3.13 12.38 2.47

Location of QTL for resistance to PBND

Conclusion To our understanding this is the first report on QTLs for PBND resistance in peanut The identified linked SSRs (IPAHM509, AHS0006, TC4G10, TC9C08) may be used in peanut breeding programme for developing PBND resistance peanut varieties after validation in different background

Thank you