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Proceedings ofthe Workshopon Ascochyta Blightand Winter Sowing ofChickpeas (Saxena, M.C.
and Singh, K.B., eds.), ICARDA. 4-7 May 1981. Aleppo, Syria
Evidence of Physiologic Races in A scochyta rabiei
of Chickpea
J.S. GREWAL
Senior Plant Pathologist, Division of Mycology and Plant Pathology,
Indian Agricultural Research Institute, New Delhi 110012, India
Blight caused by Ascochyta rabiei (Pass.) Lab. is of major importance in areas
where high humidity or rainfall occurs during the growing season of chickpea.
The disease has been reported from India (Butler 1918), Bulgaria (Atanasoff and
Kovacevski 1929), Morocco (Labrousse 1930), France (Labrousse 1931), Romania
(Savulescu 1932), Greece (Sarejanni 1929), USSR (Pavlova 1935), Iran
(Zalpoor 1963), Tanzania (Wallace 1948), Israel (Halfon-Meiri 1970) and Canada
(Morrall and McKenzie 1974). Blight was first observed in 1911 (Butler
1918) in the North Western Frontier Province of India. Luthra and Bedi (1932)
and Sattar (1933, 1934) worked out the cause and mode of perpetuation of the
disease.
Variation in Ascochyta rabiei
Luthra et al. (1939) reported six different forms of A. rabiei,namely, A, B,C, D,
E and F. Forms B, D, E and F which were biologically identical, differed from
form C morphologically while form A was non-pathogenic. Aujla (1964) reported
differences in cultural characters and pathogenic behavior of I1 isolates of
Phyllosticta rabiei on different varieties of chickpea. Later, Bedi and Aujla
(1969) suggested that the possible existence of physiologic races must be kept in
view while testing breeding material for resistance to chickpea blight.
Kaiser (1973) reported that isolates of A. rabiei from India, Iran, Turkey and
Pakistan varied greatly in growth rate, sporulation and colony appearance. He
further observed that in inoculation studies there appeared to be differences in
pathogenicity to different chickpea lines in the isolates of the pathogen from
India, Iran, Turkey and West Pakistan. Vir and Grewal (1974) reported the
existence of two physiologic races and one biotype of A. rabiei from India.
Grewal (1975) wrote a comprehensive review on ascochyta blight of chickpea.
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