Title : Soil fumigation with dazomet and metham -sodium for manangement of root- knot nematodes in protected cultivation
Phytonematodes are microscopic ubiquitous browsers of plants. Among 10 % of 30,000 parasites identified so far, root- knot nematodes ( Meloidogyne incognita and M. javanica) are attacking almost all agricultural and horticultural crops across the country. These root- knot nematodes have more than 3000 host plants. About 125million dollars are estimated to be lost due to different plant parasitic nematodes globally. Among different agricultural and horticultural crops, horticultural crops are more prone to phytonematodes. Because of the most congenial conditions prevailing in protected cultivation/ poly houses, plant parasitic nematodes especially root- knot nematodes ( Meloidogyne spp.) become more aggressive on crops like cucumber, capsicum, gerbera, carnation and other flowering plants, tomato and many vegetable crops grown in it. If nematodes attack in the early crop growth stage., then crop is totally failed incurring heavy financial losses to the farmers. In the first year, farmers may harvest good production but nematodes infection will certainly be there which is generally not noticed by farmers as no clear symptoms are visible on the crop by the farmers e.g. cucumber, capsicum, etc. However when farmers grow second crop either cucumber or capsicum without taking any control measures, then the entire crop gets failed due to severity of nematode infection. Therefore, there is a need to fumigate soils of poly houses with effective soil fumigants to bring down nematode population and subsequently, it should be fumigated every alternative year to manage nematodes in order to get desired and profitable crop production.
Among 8 different treatments including soil fumigation with metham- sodium and formalin tried on tomato, capsicum and carnation in poly houses at SKSHPAU, Palampur (HP),MPKV, Rahuri ( MS) and UAS, GKVK, Bangalore ( Karnataka) respectively, soil fumigation with Metham-Sodium @ 30 ml/m2 alone or in combination with neemcake @ 200 g/ m2 enriched with either Purpureocillium lilacinum or Pseudomonas fluorescens reduced root- knot infection by 95.45 % and there by increased tomato production by 100.91 % (ICBR : 1:3.38) over control- untreated check at Palampur. Similarly at Rahuri also, there was 54.6 % reduction in root- knot disease with 32.84 % increase in yield of capsicum (ICBR : 1:2.58). The same treatment on when tried on carnation at Bangalore also could check root- knot disease by 68.16 % and there by increased 361.65% flower production over control. However .soil fumigation with Formalin even @ 225 ml/m2 alone on in combination with neem cake enriched with either bio agents was not effective and was almost at par with control treatment for nematode management in tomato, capsicum and carnation at respective center. During 2013-14 and 2014-15, experiments conducted to manage root- knot nematodes through soil fumigation with Dazomet and Metham Sodium on tomato and cucumber in poly houses at CSKHPAU, Palampur in poly houses indicated that soil fumigation with Dazomet and Metham Sodium each @ 40 g or ml/ m2 significantly reduced root- knot disease by 78.3 % and 74.7 % with 110.9 % (ICBR 1:4.38) and 144.2 % ( ICBR: 1:5.69) increase in yields of tomato respectively. While Dazomet and Metham Sodium each @ 40 g or ml/ m2 significantly reduced root- knot disease by 74.0 % and 74.2% with 63.7 % (ICBR 1:3.76) and 65.1 % ( ICBR: 1:3.84) increase in yields of cucumber respectively.
It is, therefore, advised that farmers must go for soil fumigation either with Dazomet or Metham Sodium before taking any crop in protected cultivation.