Multiple resistance to Fusarium wilt and Phytophthora damping-off and seedling blight in safflower

Abstract

Safflower (Carthamus tinctorius L.), an important edible oilseed crop in India, succumbs to wilt (Fusarium oxysporum f.sp. carthami) and Phytophthora damping-off and leaf blight (Phytophthora parasitica var. nicotianae). Chemical control is not very effective in controlling these diseases. Host-plant resistance is an effective mode to manage them. Hence, an attempt was made in this investigation to identify and develop safflower genotypes resistant to wilt and Phytophthora. Inbred lines developed through pedigree method followed by inbreeding were screened against wilt in wilt sick plot and the same were screened against Phytophthora using agar disc inoculation technique in greenhouse. Four inbred lines viz., W-05-2028, W-2026, DSI-101 and DSI-118 exhibited resistance to wilt (>20% wilt incidence) in wilt sick plots across locations where the susceptible checks, Nira and PBNS-12 exhibited 80-90% wilt incidence. The same inbred lines were also found to be resistant to Phytophthora with <20% disease severity while the susceptible check, PBNS-12 showed 85% disease. These multiple resistant inbred lines would be of great value to breeders for simultaneous incorporation of resistance to wilt and Phytophthora blight in elite safflower lines and hybrids.