Nematodes intercepted in introduced germplasm of horticultural crops.
Imported germplasm of horticultural crops comprising seeds, stem cuttings, rhizomes, suckers, bulbs, rootstocks and tissue culture plantlets, was examined for associated plant parasitic nematodes by employing suitable detection techniques. Several plant parasitic nematodes were intercepted which include Scutellonema bradys on yams from USA; Ditylenchus dipsaci on flower bulbs (gladiolus, narcissus, tulips) and garlic bulbs from Denmark, the Netherlands and France; Aphelenchoides fragariae and Pratylenchus brachyurus in seedlings of chrysanthemum and strawberry from Australia, the Netherlands and USA; Heterodera humuli from Humulus lupulus (rooted cuttings) from Australia and Germany; Meloidogyne incognita, Pratylenchus coffeae, P. crenatus, P. penetrans. P. vulnus and Tylenchorhynchus spp. on rootstocks of apple, pear, peach, plum, apricot and Rubus species from Australia, Canada, France, Germany and USA. Interception of A. fragariae, D. dipsaci, H. humuli and P. penetrans are of high quarantine importance, as they are yet not recorded from India. Analysis of results revealed that import of horticultural crop germplasm in the form of stem cuttings, scions and tissue culture plantlets was the safest way of introduction. The infested material was salvaged using hot water treatment or nematicidal treatment. Post-entry quarantine inspection of released planting material revealed non-occurrence of exotic nematode species.