SCREENING OF SUNFLOWER GERMPLASM ACCESSIONS FOR RESISTANCE TO ALTERNARIA LEAF SPOT

Abstract

Leaf spot of sunflower caused by Alternaria helianthi (Hansf.) Tubaki &
Nishihara is a serious disease in India and under favourable conditions yield
losses may go upto 80 per cent (Agrawath et al., 1979; Balasubrahmanyam
and Kolte, 1980). Though destructive levels of Alternaria leaf spot have been
reported in India, no concerted efforts to screen systematically the available
germplasm is made to locate field resistance (Morris et al., 1983). However,
significant genetic variability for Alternaria leaf spot has been reported in
sunflower (Agrawath et al., 1979; Nagaraju et al., 1992a, 1992b). It is in this
context, that further studies were carried out to screen the available sunflower
germplasm and to determine and document the variability existing, if any,
against this disease under field conditions.