Title : Nematodes – A burning problem in protected cultivation systems
Abstract:
Plant parasitic nematodes have emerged as formidable adversaries, rivaling soil borne fungal and bacterial pathogens in inflicting severe losses with protected cultivation systems in India. Their destructive impact is particularly evident in polyhouse grown vegetable crops such as cucumber, bell peppers, tomato as well as high value cut flowers like gerbera, carnations, etc. It is well evident that controlled conditions of the polyhouse and continuous cultivation of susceptible crops has escalated the nematode population growth, rapidly reaching levels that causes significant crop losses especially by root knot nematodes (Meloidogyne incognita and Meloidogyne javanica). Moreover early root colonization by these nematodes paves the way for the secondary infections by other soil borne pathogens often culminating in the total crop failure. Despite the training components embedded in the Indian Governments supported schemes, many growers remain ill- equipped to tackle this escalating pest. Root Knot nematode infestations have become critical bottle neck leading to substantial economic losses and even closure of the protected cultivation ventures. Remedial measures were urgently warranted to ‘PROTECT’ the protected cultivation systems and the planting materials. One of the basic approach is to ‘nip the evil in the bud’ by taking the preventive measures, so as to ward off the menace of nematodes by using nematode free sites. Most of these nematode problems can be addressed or at least deferred through certification procedures. It is very heartening to express that Government of Haryana is the first state in India to anticipate this problem and respond by enforcing certification on nematode infestations in the proposed sites for protected cultivation systems. Also our experimental trails India in the naturally infested farmers field in North India, has yielded the promising results using integrated biological control strategies. Combining the physical methods like soil solarization with the bio agents like local effective registered strians viz., Pochonia chlamydosporia, Trichoderma asperellum, Paecilomyces lilacinum etc. not only suppresses nematode population but also boosted free living nematode population numbers by 23-35% over control; delivered the highest yield i.e. 46.35% increase over control conditions in bell pepper while in cucumber yield increased to 18.02% over control and root knot nematodes population decreased by 95.95% after three successive years of treatment. Further the treatment with Farm yard manure or vermicompost improved the soil heath brining the considerable changes in parameters like EC, organic carbon content, available Phosphorus, Nitrogen, micronutrients such as sulphur, boron, sodium nitrate, etc. These findings underscore the urgent need for integrated nematode management and preventive certification to ensure the sustainability and profitability of protected cultivation systems in India.
