In India, on an average, a national loss of Rs. 21,068.73 million has been estimated due to plant-parasitic nematodes. An overall average annual yield loss in major horticultural crops due to nematodes goes up to 60% under protected cultivation. The rapid spread of nematode infestation through the soil, crop residues and indiscriminate use of agro-chemicals in horticultural ecosystems is a major concern for crop protection specialists and policy makers.
Demand for high quality, export-oriented horticultural products and the need for the availability of horticultural crop produce round the year especially in off season, compelled the growers to cultivate select crops under protected cultivation in the 1980s. As a result, people started cultivation of horticultural crops under protected conditions in all the states of India. Soon nematode incidence under protected cultivation particularly became severe and led to complete crop losses because of congenial conditions of higher temperature, humidity and use of high agronomic inputs like fertilizers and plant growth promoters in poly houses.
Symptoms such as chlorosis and stunting appear after sufficient damage is inflicted. The proliferation rates of nematodes in polyhouse cultivation reached up to 10 to 30 folds more than in the open field cultivation. As yet farmers continue to incur losses in crops under protected cultivation without appropriate solutions to problems posed by nematodes. The population build up is very rapid in the poly houses, and nematode population reaches 5 – 6 times of threshold levels within 18 – 24 months, making the polyhouse cultivation a wasteful exercise. In tomato, dynamics of root knot nematode showed enhanced population build up from 1 to 30 juveniles J2/c.c. Soil within 6-12 months, which is comparatively higher in contrast to the open cultivation.
Crops such as capsicum (bell-pepper), tomato, chilli, okra, gherkins, muskmelon, watermelon, carnations, roses, gerbera and anthuriums are being grown under protected cultivation (in poly houses/ green houses/
Shade nets). These crops grown throughout India are seriously infested with nematodes such as Meloidogyne incognita, M. javanica (root-knot nematodes) and Rotylenchulus reniformis (reniform nematode). Nematode problems on all these crops under protected conditions have assumed alarming proportions leading to huge crop losses (up to 80%) in select crops. The nematode infestations exacerbate the severity of fungal diseases leading to complete crop losses.
M. incognita infection makes the plants highly susceptible to the attack of Fusarium oxsporum f.sp. dianthi. Phytophthora parasitica + M. incognita interact to produce a disease complex in gerbera leading to a reduction in the yield around 40 to 60 %. In capsicum, a pathogenic bacteria Ralstonia solanacearum gets entry into the roots infested by root-knot nematode and together produce wilting disease that reduces yield to 60-70%.
Management practices adopted by farmers include the continual use of chemical nematicides, often at higher than recommended rates resulting in a build-up of resistance. Also, biomagnification and environment deterioration due to hazardous chemicals have rendered several cultivated ecosystems unstable and non-profitable.
Nematologists at IIHR, Bengaluru standardized successful management strategies of nematodes and other disease complex using biopesticides like Paecilomyces lilacinus, Pochonia chlamydosporia, Trichoderma harzianum, T. viride and Pseudomonas fluorescens. Farmers who adopted IIHR technology reduced the use of agro-chemicals to 40 to 45% and obtained 30 to 35% increased yields in capsicum, gerbera, and carnations.
Preparation of beds
- Land should be thoroughly plowed, and soil should be brought to a fine tilth. Before preparation of the beds in the poly-house, incorporate 20 tons of FYM enriched with the biopesticides in the soil.
- Raised beds are to be prepared after bringing the soil to ?ine tilth. Bed size can be according to the requirement and the type of crop grown.
- Add recommended doses of fertilizers. Also add carbofuran or phorate @ 50g/sq.m + 200g neem/ pongamia/ mahua cake enriched by bio-pesticides per sq. m.
- Further, incorporate bio-pesticide enriched FYM@ 2kg/sq. M or biopesticides enriched vermicompost @ 500g/sq.m in top 18 cm of soil in the beds.
- Water the beds for 7-10 days for proper decomposition of these organic materials.
Process of Enrichment of FYM
1 ton of Farm Yard Manure has to be enriched by mixing with 2 kg each of Pseudomonas fluorescens + Trichoderma harzianum + Paecilomyces lilacinus. It has to be covered with mulch and optimum moisture of 25
– 30% has to be maintained for 15 days.
Process of Enrichment of neem/ pongamia/ mahua cake
- 1 ton of neem/ pongamia/ mahua cake has to be enriched by mixing with 2 kg of each of Pseudomonas fluorescens + Trichoderma harzianum + Paecilomyces lilacinus. It has to be covered with mulch
, and optimum moisture of 25 – 30% has to be maintained for a period of 15 days.
- Once in a week thoroughly mix the neem cake for maximum multiplication and homogenous spread of the microorganisms in the entire lot of neem cake
Process of Enrichment of vermicompost
- 1 ton of vermicompost has to be enriched by mixing with 2 kg of each of Pseudomonas fluorescens + Trichoderma harzianum + Paecilomyces lilacinus. It has to be covered with mulch and optimum moisture of 25 – 30% has to be maintained for a period of 15 days.
- Once in a week thoroughly mix the vermicompost for maximum multiplication and homogenous spread of the microorganisms in the entire lot of vermicompost.
- The organic formulation containing Pseudomonas fluorescens and Trichoderma harzianum has to be sprayed on the plants at regular intervals of 20 days at a dosage of 5g/ lit or 5ml/lit.
- Alternately, take 20 kg of neem/ pongamia/ mahua cake enriched in the above-mentioned manner and mix it in 200 litres of water, leave it for a period of 2-3 days. Filter this suspension and use it for spraying
by mixing 250ml of suspension in 1 lit. of water at regular interval of 20 days.
Drenching or application through drip irrigation system
- The IIHR patented organic formulation has to be given through drip/ by drenching @ 5g/ lit or 5ml/ lit. at regular interval of 20 days.
- Alternately, take 20 kg of neem/ pongamia/ mahua cake enriched in an above-mentioned manner and mix it in 200 litres of water, leave it for a period of 2-3 days. Filter this suspension and use it for
drenching at regular interval of 20 days.
- Indian Institute of Horticultural Research