THE EFFECT OF DITYLENCHIASIS INFESTATION OF SEED TUBERS ON POTATO PRODUCTIVITY

Abstract

In a field experiment to study the harmfulness of potato ditylenchiasis, 15 externally healthy, 15 with weak signs of ditylenchiasis (from 1/10 to 1/5 of the surface of potatoes affected by ditylenchiasis) and 15 with pronounced symptoms of ditylenchiasis (from 1/3 to 1/2 of the surface of potatoes affected by ditylenchiasis) of tubers of the Nadezhda variety were planted. When planting potato tubers severely affected by ditylenchiasis, 40% of the tubers rotted due to their defeat by wet rot. Another 40% of plants showed a slowdown in growth, a decrease in the size of leaves and their chlorosis. After a month, the plants did not differ from those unaffected by ditylenchiasis. In the remaining 20% of plants grown from poorly affected tubers, potato bushes practically did not differ from unaffected plants. In the variant of the experiment with seed tubers slightly affected by ditylenchiasis, the height of the invaded plants on July 1, was on average 25% lower than that of the control plants (on average 51.7 cm). On August 1, the height of plants infested with tuberous nematode was 14 cm lower compared to control plants (on average 72.9 cm). The average number of stems per invaded plant was also less – by 14%, compared with control plants. The mass of tubers in plants grown from tubers affected by ditylenchiasis (490 g) was 29.3% less than that of the control tubers (693 g). The average number of tubers in the control plants (6.7 tubers) was higher than in the invasive plants – by 22.4%. The number of non-standard tubers (38%) in the invaded plants was greater than in plants grown from apparently healthy tubers (26.9%).