Awardees and their employment status
- First in the world to award post-graduate degree in Nematology. Awarded107 M.Sc. and 141 PhD in Nematology till 2016. Awardees from the Division of Nematology are well placed as Scientist, Assistant Professor, Administrators etc. in ICAR, State Agricultural Universities (SAUs), and Government Departments within India and abroad.
Professional Society of Nematology
- Founded Nematological Society of India in 1969, with its headquarters at this Division and started publication of Indian Journal of Nematology since 1971.
The Division has made the following achievements during the course of time
Nematode taxonomy and biosystematics:
- Identified and documented most of the genera and species ofplant, soil and insect nematodes occurring in India.
- Highlighted the emerging nematode problems in vegetables, cereals, pulses and oilseed based cropping systems.
- Utilized biochemical and molecular techniques for differentiation of closely resembling nematode species belonging to genera Meloidogyne and Heterodera.
- Identified races of root-knot, reniform and cyst nematodes using host differentials and DNA polymorphism.
- Identified genes of several plant and entomopathogenic nematodes and their sequences have been deposited in gene bank.
- Proposed novel classification schemes and developed diagnostic keys for nematode taxa.
- Characterized phytonematodes for easy identification of species
- Established the National Nematode Collection of India (NNCI) : Information on the accession of NNCI is available in the form of database:
Key nematode pests of crops:
- Root-knot (Meloidogyne incognita and M. javanica) and reniform (Rotylenchulus reniformis) nematodes as major problems in vegetables; cyst (Heterodera cajani) and root-knot (Meloidogyne spp.) nematode as key nematode problems in pulse crops and root-knot nematodes (M. arenaria and M. incognita) as main problems in oilseeds.
- Pioneer in work on races of reniform nematode and identified biotypes/races in populations of root-knot and cereal cyst nematodes.
- Cereal cyst nematodes (H. avenae, H. zeae and H. sorghi) are serious nematode problems in wheat, maize and sorghum, respectively, in several north western states of the country.
- M. graminicola emerged as an important pest in rice-wheat cropping system.
- Meloidogyne spp. are threat for cultivation of polyhouse crops (tomato, capsicum, cucumber etc.) under protected cultivation system.
- Problem of root knot nematodes (Meloidogyne incognita, M. javanica and M. arenaria) in guava and potato have been identified as limitations for profitable cultivation.
- Established a School of Molecular Nematology for future use through generating substantial knowledge resources in terms of genes through sequencing whole genomes of M. graminicola and H. avenae; transcriptomes of M. graminicola, H. avenae, H. cajani, M. indica (infecting neem), M. javanica and Heterorhabditis indica, an EPN and its bacterial symbiont, Photorhabdus luminiscens.
- Several nematode resistant transgenic events of brinjal and tomato are at different stages of development and evaluation using RNAi technology against M. incognita.
- Reported transcriptome of infective juveniles (IJs) – the stage of an entomopathogenic nematode (EPN), Heterorhabditis indica used for formulation of insect biopesticide. This information is useful for genetic enhancement of the strains and improving shelf-life.
- Neurobiolgy of host recognition of M. incognita studied and for the first time globally and several chemosensory genes identified, cloned and validated for their role in signal transduction during interaction with various hosts.
- Demonstration of site of expression of a very crucial neuropeptide gene, FMRFamide like peptide 18 (flp18) in the neuorons AWA, AVA, M2, M3 of sub-ventral and retro-vesicular ganglion of the nervous system of M. incognita. Since this gene is responsible for essential functions like host recognition, olfaction, chemotaxis, fat metabolism and reproduction, it could be a very potential target for either designing transgenics or anti-nematicidal molecules.
- Demonstration of effectiveness of RNAi silencing of multiple gene simultaneously in reducing the development and reproduction of M. incognita
- Demonstrated the interaction/cross-talk among the effectors for parasitism during penetration of M. incognita on brinjal
- Demonstrated the dual advantage of host delivered RNAi of M. incognita genes in providing protection both at initial exploratory stage and post establishment leading to reduction of population build up in the soil
- For the first time identified, cloned and validated eight housekeeping genes essential for gene expression studies in 11 different tissues in tuberose and demonstrated their stability under both biotic and abiotic conditions. This would facilitate quantification of changes in gene expression due to stress and other various conditions.
- Host delivered RNAi of genes of M. incognita in tobacco and brinjal: Two FMRFamide like neuropeptide genes, flp14 and flp18 to disrupt the neuromotor activity of the nematodes, and three esophageal gland genes, msp1, msp18 and msp20 responsible for infection, feeding cell formation and maintenance in host roots were targeted for gene silencing through host delivered RNAi in order to disrupt the disease and life cycle for effective nematode management. A total of about 100 transgenic events comprising 15-30 events for each of the gene have been generated and confirmed for gene integration by southern blot analysis, expression analysis of siRNA generation by northern blot analysis, transgene expression by quantitative PCR and demonstration of down regulation of target gene silencing in the nematodes feeding on transgenic plants confirmed the specific gene silencing responsible for observed phenotypic effects of gene silencing like reduction in nematode induced root galls, number of female nematodes, reproduction and multiplication factor. The brinjal transgenics expressing flp18, flp14 and msp1 have been found to be performing stably even at T3 generation and ready for transfer to industry.
- Heterodera avenae Transcriptome Database (HATDB) developed with a view to provide most comprehensive information about H. avenae transcriptome - the most relevant part of the genome. The HATDB is freely available resource, which may provides user researchers a portal to search, browse and query the data to assist the research on H. avenae and other plant parasitic nematodes (available at http://insilico.iari.res.in). Current version of assembly with roughly 27,000 transcripts is uploaded for global access. We have also included protein translation of the transcripts for BLAST analysis. Further, sequence retrieval system is provided for extracting sequence based on database identifier, gene ontology (functional information) and pfam (protein family) domains.
- Evaluated about 45 genes of H. avenae by in vitro RNAi silencing to determine their role in infection, development and reproduction
- Identified several unc genes in M. graminicola and validated by RNAi
- For the first time cloned several nlp genes in M. incognita and demonstrated their role in infection, development and reproduction by RNAi
- Developed a very stringent in vitro screening for identifying resistance in rice and quantified the expression of several genes of SA, JA and EA pathways for their comparison between resistant and susceptible cultivars at early and established infection stages
- Filed an Indian and a US-PCT patents for utility of flp14 of M. incognita for its management
- DNA finger prints of several plant parasitic and entomopathogenic nematodes have been developed
- Established nematicidal potential of neem and other botanical parts and products against root-knot, reniform and pigeon pea cyst nematodes in vegetables and pulses.
- Developed protocols for seed treatment with neem products and nematicides in direct seeded cereal, vegetable, flower, pulse and oilseed crops for the control of root-knot, reniform and cyst nematodes
- Identified a large number of sources of nematode resistance in vegetables, pulses and oil-seeds against root-knot and reniform nematodes and in cereals against cyst nematodes and a few of them have been used in breeding resistant varieties.
- Determined damage threshold levels and developed crop damage- nematode population density models for several crops
- Studied population dynamics of economically important nematode species in relation to cropping systems and agro-climate and a few crops like Crotalaria juncea, Brassica juncea and B. campestris could be utilised against root knot nematode by incorporating them in a cropping system.
- Worked out biology, population dynamics and integrated management package for M. graminicola infecting both rice and wheat.
- Demonstrated soil solarization of nursery beds as a highly effective technique for controlling nematodes in transplanted crops such as tomato, brinjal, chili and rice.
- Developed a simple management package against ear-cockle/seed gall nematode, Anguina tritici infecting wheat.
- Pasteuria penetrans originally isolated from Heterodera cajani was found capable of parasitizing and completing its life cycle on Globodera spp. prevalent in Ooty.
- Developed integrated nematode management (INM) packages utilizing combinations of cultural and chemical control methods and their efficacy have been demonstrated in multi-location trials in cereal, vegetable, pulse, and oilseed crops.
- Metam sodium, an effective chemical when applied beneath soil could manage root knot damage in tomato under polyhouse cultivation.
- Established a Nematode Disease Diagnostic and Advisory Clinic to assist and advise farmers in diagnosis and management of nematode problems.
Biological control of nematodes:
- Identified the biocontrol potential of nematode specific indigenous isolates of Pasteuria penetrans on M. incognita and H. cajani
- Advances made in understanding the mode of attachment of the endo spores of the bacterium, Pasteuria penetrans on the nematode cuticle.
- Nematotoxic metabolites from terrestrial cyanobacterium, Synechococcus nidulans played significant role in hatch inhibition in Meloidogyne incognita, M. graminicola, Heterodera avenae and H.cajani; the polar fraction proved more nematicidal than no-polar fraction. Application of fuller’s earth based formulation of S. nidulans at 0.5% w/v resulted in highest reduction of root galling, number of egg masses and nematode multiplication rate.
- Actinomycetes, Streptomyces purpeofuscus (MTCC 6473) and S. lavendulae (MTCC 706) possess nematotoxic metabolites that cause significant hatch inhibition and reduced juvenile invasion with significant reduction in root galling and reproduction factor in M. incognita infecting tomato.
- An indigenous isolate of Pasteuria infecting M. incognita was found to be highly specific; the spore attachment bioassays on other species of Meloidogyne prevalent in India indicated its host specificity. The pre-incubation of Pasteuria isolate with other soil bacteria viz., Bacillus cereus, B. subtilis and B. pumilus resulted in a decline in spore attachment.
- Screening and evaluation are in progress for indigenous isolates of Trichoderma spp. from Indian Type Culture Collection (ITCC) for their nematicidal potential.
- The Division undertakes basic and applied research on entomopathogenic nematodes (EPNs) and their symbiont bacteria, such as EPN and bacterial taxonomy, genomics and transcriptomics, symbiosis, ecological characterization, mass culturing, formulation and application technologies.
- The Division provides need based support to the other EPN research laboratories in various parts of India.
- The heat-tolerant EPN species Steinernema thermophilum described from the Division was licensed to Multiplex Biotech International Ltd. for commercialization.
- A gel-based formulation of nematode S. thermophilum ‘Pusa NemaGel’ was developed and is available for commercialization through the Institute Zonal Technology Management and Business Process Development Unit.
- Galleria cadaver based application technology for EPN, Heterorhabditis indica developed by the Division has been found highly promising for management of white grubs and apple root borers in sugarcane crop in western UP and in Himachal Pradesh, respectively.
Biosystematics laboratory, Conference room, Library, PG laboratory, Disease diagnostic clinic, Tissue culture laboratory, Interactive board, SEM, Microscope with Image analysis, modern glass-house, Micro-plots, Autoclavable Biofermentor, RT-PCR, latest Books on rare collections and Nematology Journals in the Divisional Library.
Technology Commercialized and Patents Granted
The invention relates to the field of double stranded RNA (dsRNA) mediated gene silencing of root-knot nematodes. The invention particularly provides an effective method for reducing the number of reproducing population and the number of progenies per individual of the root-knot nematodes. The invention also relates to host-delivered dsRNA for controlling infection of root knot nematodes.
Uma Rao, Pradeep Papolu, Nagavara Prasad Gantasala, Divya Kamaraju, Prakash Banakar & Mukesh Kumar
ICAR & DBT No. 14/652,096 dated 14 December, 2013
United States Patent: NO. US10,308954 dated June 4, 2019