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NOTES ON TAXONOMY AND BIOLOGY: Like other cyst forming nematodes, it has sedentary endoparasitic habits. Cysts are persistent tanned sacs derived by the female body that contain the eggs. Cysts persist in soil for many years. Second-stage juveniles (J2) emerge from the cysts, penetrate host roots, and establish a specialized feeding site (syncytium) in the stele. They develop into swollen females, which retain the eggs. They rupture root cortex, protrude from root surface.and produce egg masses. At the end of the reproductive phase, females die and become lemon shaped brown cysts. These cysts are ambifenestrate and provided by a well-developed underbridge and bullae.
GEOGRAPHICAL DISTRIBUTION: Egypt, India and Pakistan.
HOSTS: Black gram (Vigna mungo), clusterbean (Cyamopsis tetragonoloba), cow-pea (Vigna unguiculata), garden pea (Pisum sativum), kidney bean (Phaseolus vulgaris), lablab (Lablab purpureus), moth bean (Vigna aconitifolia) and sesame (Sesamum indicum) are the most damaged field crops by this nematode. Other hosts include Corkwood tree (Sesbania cannabina), Rhynchosia and sunn hemp (Crotalaria juncea).
CROP LOSSES: Nematode damage has been reported on many agronomic crops. Results of greenhouse studies showed crop losses ranging 14-24% on pigeon pea (Sharma et al., 1993).
MEANS OF MOVEMENT AND DISPERSAL: Nematodes are dispersed by soil debris and plant material contaminated with the cysts.
RATING: (M) Although the crop losses caused by this nematode have not been quantified under field conditions, the widespread damage observed in India and the establishment of this pest in Egypt indicates that a complete PRA should be completed for this nematode.
REFERENCES:
CAB International. 2001. Heterodera cajani in
Crop protection compendium, global module, 3rd editon. Wallingford, UK:
CAB International.
Luc, M. 1986. Cyst nematodes in equatorial and hot
tropical regions Pp.355-372. in F. Lamberti and C.E. Taylor
eds. Cyst nematodes. New York and London: Plenum Press.
Sharma, S. B., Y. L. Nene, M. V. Reddy, and D. McDonald.
1993. Effect of Heterodera cajani on biomass and grain yield of
pigeon pea on vertisol in pot and field experiments. Plant Pathology 42
(2): 163-167.
Sikora, R. A. and N. Greco. 1990. Nematode parasites
of food legumes. Pp. 181-235 in M. Luc, R. A. Sikora, and J. Bridge
eds. Plant parasitic nematodes in tropical and subtropical agriculture.
Wallingford, UK: CAB International.