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conidia were not blown about by wind but were carried in rain water and rain
splashing from diseased plants to healthy adjacent plants when strong winds.
accompanied rains. However, infected parts of the blighted plants become brittle,
break off easily, and are carried by strong winds for some distance (Luthra et
al. 1935).
The viability of the blight fungus in chickpea debris was studied by Luthra et
al. (1935). They found that 1-year old debris carried viruient infection whereas
the infective capacity of the 2-year old debris declined considerably and the 3year
old debris could cause little or no infection. It was not possible to isolate the
fungus from blighted seed kept for 2 years in the laboratory. The blighted debris
exposed to summer rain was rendered less harmful than the material lying in dry
condition where the rainfall was 50 mm. A period of 60-70 days was sufficient to
kill the fungus totally. The diseased debris buried in the soil at any depth from
5-15 cm was rendered harmless for subsequent chickpea crops, especially in the
presence of high soil moisture (Sattar and Hafiz 1952).
Treatment of the infected chickpea seed with sulphur and copper carbonate
could not completely control the disease. The fungus when grown in culture and
kept in dried form retained its viability even after a period of 8 months (Sattar
and Hafiz 1952).
Epidemiology of Chickpea Blight
Serious epidemics of blight have occurred in Pakistan and scientists have tried to
determine a relationship between temperature and rainfall with the spread of the
disease. Because weather data are scarce in the areas where chickpea blight
usually occurs, it has not been possible yet to pinpoint the factors which trigger
the spread of the disease in epidemic form. No regular studies have so far been
made to elucidate the phenomenon.
Kausar (1960, 1968), Kausar and Ahmad (1967) and others have reported
chickpea blight epidemics during the following years:
1928-29, 1929-30 and 1930-31 The crop badly suffered in Attock; the chickpea area
was reduced drastically.
1936-37, 1937-38, 1938-39 and Almost complete failure of the crop in Attock
1939-40 and other adjoining districts.
1947-48, 1948-49, 1949-50, Blight years in succession. The crop suffered to varying
1951-52 and 1953-54 degrees in different years.
1956--57, 1957-58 and 1958-59 Severe blight epidemic in chickpea growing area
1972-73 and 1973-74* Mild blight years
1975-76* Mild blight years
1978-79 and 1979-80" Severe epidemic of chickpea blight.
1980-81* Up to 15% crop loss caused by chickpea Nlight; most of the
chickpea area was diverted to wheat and oilseed crops.
* Annual Research reports, PL-480 Project on Gram Improvement
from 1971-1981, University of Agriculture, Faisalabad.