Integrated potato cyst nematode (Globodera sp) management strategies for south Indian hills
The eggs present in the hard coated cysts of potato cyst nematodes (PCN) Globodera sp hatch out only in the presence of potato (Solanum tuberosum L) root exudates of host plants. Non-availability of host plant along with the application of synthetic chemicals is expected to control this hard coated soil borne pest without much negative impact on the environment. Thus, the effects of seven different two year crop rotations of susceptible (Kufri Jyoti) and resistant (Kufri Swarna) cultivars of potato along with three non-host crops (cabbage-Brassica oleracea, carrot-Dacus carota and radish-Raphanus sativus) of PCN, in different crop rotation combinations were evaluated with an aim to find out the best rotation suitable to manage the PCN population. Effective nematode reduction (47% in 2 years) could be achieved by rotating susceptible potato variety with the resistant (resistant to both G. pallida and G. rostochiensis) one, and application of carbofuran @ 2.0 kg a.i. ha−1 for each crop of potato. However, higher economic returns (BC ratio: 2.91) were recorded in the treatment potato-cabbage-carrot-potato, along with carbofuran application to potato, which could not contain the nematode buildup substantially (5%) in two years rotation. Alternating the resistant potato with non-solanaceous crop in between two susceptible potato crops could bring down the PCN population only to the extent of 20–25%. The effectiveness of growing non-solanaceous crops to contain PCN populations in rotation is comparatively lower (20 to 25%) when compared with resistant potato varieties (47%). This integrated strategy with negligible negative impact on environment is recommended for PCN management.