Breeding and Characteristics of a Pepper (Capsicum annuum L.) Rootstock Cultivar ‘Murasaki L4 Daisuke’ with Violet Hypocotyl and Resistance to Bacterial Wilt and PMMoV

Abstract

In the present study, ‘Murasaki L4 Daisuke’ was bred as a new cultivar for the rootstock of pepper (Capsicum annuum L.), showing resistance to both bacterial wilt caused by Ralstonia solanacearum and to mosaic caused by Pepper mild mottle virus (PMMoV). Moreover, ‘Murasaki L4 Daisuke’ had the marked advantage of easy identification between the scion and rootstock at the time of grafting because of the development of anthocyanin on the hypocotyl. In the inoculation test of a highly virulent strain of R. solanacearum, ‘S’, ‘Murasaki L4 Daisuke’ showed resistance similar to ‘Dai-Power’ and ‘Daisuke’. In the inoculation test of PMMoV, which is classified as pathotype P_1.2.3, ‘Murasaki L4 Daisuke’ was recognized to have an L⁴ gene. By the quantification of anthocyanin, ‘Murasaki L4 Daisuke’ was confirmed to develop an approximately three-fold greater amount of anthocyanin on its hypocotyl compared with conventional cultivars. ‘Murasaki L4 Daisuke’ showed the same fruit productivity compared with ‘Daisuke’, when accompanying the scion ‘Miogi’.