Mining new scab resistance alleles in apple (Malus × domestica Borkh.) germplasm of Kashmir: Towards breeding scab free apple cultivars

Jahangir Ahmad Dar; Sajad Majeed Zargar; Rameez Nazir Rather; Aijaz A. Wani

Jahangir Ahmad Dar Proteomics Laboratory, Division of Plant Biotechnology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Shalimar, Srinagar 190 025
Sajad Majeed Zargar Proteomics Laboratory, Division of Plant Biotechnology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Shalimar, Srinagar 190 025
Rameez Nazir Rather Proteomics Laboratory, Division of Plant Biotechnology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Shalimar, Srinagar 190 025
Aijaz A. Wani Proteomics Laboratory, Division of Plant Biotechnology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Shalimar, Srinagar 190 025

Keywords: Malus × domestica, Apple scab, Vf gene, Venturia inaequalis

Abstract

Apple an important fruit crop in Kashmir ranks first in all the fruits grown here. It is commercially the most important horticultural crop grown in temperate parts of the world. To control scab in Apple a lot of fungicides are being used however, an alternative approach to fungicide application is the use of scab resistant cultivars as a genetic stock. Therefore, there is an urgent need to identify more cultivars resistant to scab with maximum genes and can be used for apple breeding. In view of this, one hundred apple cultivars grown in Kashmir Valley were screened for the presence of Vf gene conferring resistance against apple scab. Eight trait linked markers were used so for and among them three markers like AL07, AM19, and CH05e03 proved to be useful to distinguish the resistant cultivars from the other apple germplasm. These three markers have amplified resistant fragments in five cultivars. Thus out of the total of 100 cultivars investigated in the present study, only five cultivars namely Shalimar I, Shalimar II, Dubhour, Gold Spur, and Crab apple were found to harbour resistant alleles which may be resistant to some of the races of V. inaequalis. Among the five cultivars harbouring the scab resistant alleles for some races of V. inaequalis, three cultivars namely, Shalimar I, Shalimar II, and Dubhour, which contain the maximum number of scab resistance alleles can be used as parents in further breeding programms to develop more resistant apple cultivars with high market acceptance.