Survival and Population Dynamics of Foliar Nematode, Aphelenchoides besseyi Infecting Tuberose in West Bengal, India

Foliar nematode, Aphelenchoides besseyi is of great concern for profitable cultivation of tuberose (Polianthes tuberosa L.). Studies on various parts of tuberose plant for understanding their role in dissemination of A. besseyi revealed that flowers, stalk, leaf, scales and bulbs of ‘calcutta single’ cultivar were the major sources of nematode infection. Further, A. besseyi was found infecting tuberose in field naturally either through infected bulbs or infested plants parts. Fourteen weed species growing in the tuberose fields showed no foliar nematode infection. Among the other nematode species identified from rhizosphere of tuberose were Meloidogyne incognita, Hoplolaimus indicus, Helicotylenchus multicinctus, Tylenchorhynchus mashhoodi, Rotylenchulus reniformis, Criconemoides onoensis, Pratylenchus zeae and Mylonchulus spp. The nematode species which was consistently recovered from infested flowers was the foliar nematode, A. besseyi. However, the nematode species was not detected in soil samples over two years observation on the nematode infested fields. The high population of A. besseyi was observed when tuberose crop growing faster and producing greater flowers (April-July) and low population was recorded when the crop was entering into senescence during September to December months coinciding with low temperature, rainfall and relative humidity.