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SummaryThe development oi D. dipsaci depends on the cultivar; differences being observed in the rate of multiplication following artificial inoculation of seedlings, in the rate of development of eggs and in the number of progeny.The plant reacts to the penetration by stem nematode in different ways: generally D. dipsaci induces a distinct swelling of the stem-root junction. With oat, a relation exists between the percentage of swelling plants and the numbers of nematodes in plants; for a susceptible variety, the quantities of nematodes are higher if the percentage of plants with swelling is high. With lucerne, lack of swelling and inhibition of shoot elongation is connected with resistance to development. There is a correlation between symptoms and the multiplication rate of the nematode. It is possible to determine a visual lest of resistance. |
