I - --ii

hand hoeing. During the early growth phase, the crop grows very slowly and the
weeds which grow fast deplete soil moisture and nutrients. The important weeds
in the crop are Chenopodium album, Asphodelus tunnifolius, Argemone mexicana,
Convolvulus arvense and Trigonella polycerrata.
Harvesting and Threshing Methods
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The crop is harvested manually with sickle when most of the pods and leaves turn
brown. The crop is stacked in the fields till it becomes dry. Threshing is done
either by trampling the crop with bullocks or by running a stone roller over it.
The winnowing is done to separate the grain from the straw.
Ascochyta Blight Research
This disease is known by various names such as gram blight, ascochytosis,
anthracnose, rabia or scorch of chickpea. The causal organism of chickpea blight
was first named Zythia rabiei by Passerini (1867). The other synonyms of the
fungus are Mycosphaerella rabiei, Phyllosticta rabiei, Phoma rabiei and Ascochyta
rabiei, the last name being the most accepted.
Inheritance of Resistance to Ascochyta Blight
Hafiz and Ashraf (1953) crossed F8 and Fl 0 (two resistant types) to two susceptible
Punjab types Pb7 and C7; Vir et al. (1975) crossed 1-13 (resistant) and Pb7,
NP58 and RSI0 (susceptible type) including the reciprocals. In all the cases, the
Fls were resistant and the F2s gave fit to 3 resistant:l susceptible, indicating
monogenic difference between the lines used in the crosses and resistance being
dominant.
Review of Past Research on Ascochyta Blight
Many workers (Luthra and Bedi 1932; Sattar 1933; and Luthra et al. 1935), have
investigated the life history of blight and its control measures and have reported
that zhe maximum, optimum and minimum temperatures for germination of
spores and growth of the fungus were 32.5, 20, and below 10°C, respectively. The
disease was carried from one season to the other by sowing infected seeds and by
diseased plant debris which remain lying on the surface of the soil. They also
reported that the disease spreads from plant to plant and field to field by
secondary infection carried by spores and diseased parts of plants. The fungal
spores are not blown by wind in dry weather. They recommended the use of
disease-free seed, sanitation and a 2-to 3-year rotation for control of the disease.
Sattar (1933) observed that susceptibility of plants increased with age, being