NRCL - Research Achievments

Genetic Resource Management and Crop Improvement

  • Three new varieties of litchi namely ‘Gandaki Yogita’, ‘Gandaki Sampada’ and ‘Gandaki Lalima’ were developed
  • One new variety of longan ‘Gandaki Longan-1’ was identified and released at institute level
  • Seventy two accessions of litchi and allied species were collected from indigenous sources and are being maintained in the germplasm repository
  • One hundred and fifty one accessions of longan have been collected and being maintained in the Genetic Resources Field GeneBank
  • DUS guidelines for evaluation of litchi cultivars have been standardized
  • Protocol for long term storage of litchi pollens has been standardized
  • Hybrid progeny involving litchi cvs. ‘Shahi’, ‘China’, ‘Bedana’ and ‘Kasba’ were developed and are under evaluation
  • Eighty nine superior clones of litchi were identified and propagated for their detailed evaluation
  • About 1200 seedlings of cvs. ‘Shahi’ and ‘China’ are under evaluation. Further, seedlings are also being raised from the selected clones

Crop Production

  • Rejuvenation technique for old senile orchard was standardized, demonstrated and adopted by farmers
  • Refined potting media for healthy and vigorous plant with higher survival in nursery. For raising air layers in nursery potting mixture containing river bed soil+ vermicompost (2:1) +DAP (5 g) was found the best. Dip treatment with Rhizobacteria (2.0 %) increased survival rate of litchi air-layers up to 90%
  • Suitable crops for growing under shade of litchi trees were identified. Inter-space utilization protocol for young non-bearing litchi orchards has been developed with (1) Litchi-Banana (2) Litchi–Cowpea-Potato-Onion (3) Litchi-Okra-Gladiolus models with high B:C ratio of 2.38, 1.53 and 1.37, respectively
  • Elephant foot yam, turmeric, colocasia, maize and potato were found highly suitable as intercrops under partial shade of juvenile litchi plants
  • Tree spacing of plants at 6×4 m was found the best for optimum space utilization and yield optimization. Significantly higher yield was harvested at 8×4 m and 6×4 m spacing of the trees as compared to 10×10 or 8×8 m spacing
  • An integrated nutrient management (INM) schedule was developed. Optimum doses of NPK and their split application were standardized for cvs. ‘Shahi’ and ‘China’
  • Problem of alternate bearing in litchi solved by girdling the litchi primary branches after emergence of second vegetative flush. Technology was demonstrated successfully in farmers’ orchards with beneficial impact on yield and fruit quality.
  • Foliar application of planofix @ 2.5 ml/10 L or NAA 20 mg/ L one week after fruit set significantly checked fruit drop
  • Beneficial effect of microbial consortia including myorrhizal association was established. A technology viz, ‘NRCL microbial consortium for enhanced growth, productivity and quality of litchi” was released which is a carrier based formulation of three microbes, Arbuscular mycorrhiza, Azotobacter chroococcum and Trichoderma viride isolate NRCLT-01.
  • Chemicals / growth regulators for flower induction were identified. Ethrel spray @150 ppm in litchi cv. ‘Shahi’, ensured regular flowering, and hastened fruit maturity by 5-6 days (with TSS 18 degree brix). Paclobutrazol (PBZ) @ 4.0 g per m canopy diameter applied in alternate years in litchi cv. ‘China’ during September month bore the highest no. of panicles per tree (265 panicles)
  • Bagging of individual litchi bunches in cv.Shahi with perforated butter paper was found the best for production more class-I category fruits with reduced sun-burn and cracked fruits
  • Litchi-based cropping system for pond and lowland areas was developed with model-I (banana + cowpea-cabbage) and model-II (papaya + cowpea-cabbage with fishery) to be the best

Crop Protection

  • Major pests of litchi prevalent in the area were identified. Borer complex of litchi are most important as they extensively damage the developing and matured fruits reducing the yields and marketability
  • Three new threats of pests in litchi were identified viz., red weevil (Apoderus blandus), semilooper (Perixera illepidaria) and bagworm (Eumeta crameri)
  • Panicle blight caused by Alternaria alternata was identified as the most important disease of litchi. Disease incidence and severity of blights of leaf, panicle and fruits was continuously were recorded over the years. Ecophysiology of A. alternata and epidemiology of the disease was studied.
  • Integrated management schedule for economically most damaging pests and diseases of litchi were developed
  • Pesticides residue analysis of recommended insecticides and safe waiting period for insecticides used in litchi were determined
  • Technology for mass production of NRCL Trichoderma (Trichoderma viride strain NRCL T-01) and development of microbial consortium for quality litchi production.
  • An effective management strategy for wilt using NRCL Trichoderma was developed

Postharvest and Value Addition

  • Correct harvest maturity in litchi have been standardized
  • Quantum of pre- and post-harvest losses incurred at different stages of litchi production and marketing (Farm to Fork) have been established
  • Hydro-cooling protocol for litchi has been standardized
  • Pre and postharvest protocol for maintaining fruit quality and improving shelf life has been developed
  • Technology for bagging of litchi bunches for improving fruit quality has been developed
  • Physiological and biochemical basis of pericarp browning in litchi has been established
  • Different packaging techniques such as CFB box, thermocol, and modified atmosphere packaging have been standardized
  • Technique for preparation of litchi wine has been standardized
  • Technique for preparation of litchi nut has been standardized
  • Osmo-mechanical method of prepration of dehydrated litchi pulp has been developed and refined
  • Techniques for preparation and preservation of litchi pulp and beverages have been developed