1. Principles and Practices of Nematode Control
Walia CCSHAU
3/31/2017

2. Nematode control required only if Pi > Pt
Terminology
Pi = Initial Nematode Population
Pt = Threshold level (ETL, Damaging level, Pathogenic level)
Pf = Final Nematode Population
Nematode control required only if Pi > Pt
Nematode Control - aims at eradication
Nematode Management – aims at keeping the nematode population below Pt
Walia CCSHAU
3/31/2017

3. Walia CCSHAU
3/31/2017

4. Methods of Nematode Management
Cultural
Physical
Chemical
Host resistance
Regulatory
Biological
Integrated
Walia CCSHAU
3/31/2017

5. Cultural Methods Crop rotation
Growing a non-host crop in between two susceptible ones
Non-host crop must be economically viable, locally acceptable and should not promote any new pest of disease problem
Rotation of wheat with gram, mustard for the control of Heterodera avenae
Walia CCSHAU
3/31/2017

6. Crop Rotation Wheat - Wheat Fenugreek - Wheat Wheat - Wheat
Oats - Wheat
Walia CCSHAU
3/31/2017

7. KEEPING THE FIELD BLANK
2. FALLOWING
Cultural Methods
Fallowing
PPNs are obligate parasites, cannot survive without food
Flooding
PPNs are aerobic; they will die due to asphyxiation in flooded lands
KEEPING THE FIELD BLANK
Walia CCSHAU
3/31/2017

8. Cultural Methods Propagation through healthy planting material
Many nematode diseases spread through infected planting material; burrowing nematode in banana suckers, citrus nematode in infected citrus saplings, earcockle disease of wheat with contaminated seed
Removal or destruction of infected plants
Removal and destruction of root stubbles soon after harvest
Organic manuring/Amendments
Decomposition products (fatty acids) are toxic to PPNs
Increase in the population of micro-organisms, including nematode antagonists
Improved plant growth leads to tolerance against nematode damage
Walia CCSHAU
3/31/2017

9. Cultural Methods Trap crops Antagonistic crops
Nematodes penetrate but fail to develop inside some crops like Crotalaria; can be used as green manure after a few days
Antagonistic crops
Root exudates of certain crops contain nematoxic compounds
Onion
Garlic
Tagetes (ᾳ-terthienyl)
Asparagus (asparagusic acid)
Can be used as interculture
Walia CCSHAU
3/31/2017

10. Cultural Methods Time of sowing Soil solarization
Advancing crop sowing by 2-3 weeks to escape nematode infection; older crop suffer less damage even if infection occurs
Soil solarization
Deep summer ploughing
Plastic mulching
Walia CCSHAU
3/31/2017

11. Physical methods
Most nematodes cannot tolerate temperature > C
Hot water treatment of infected plant material (bulbs, corms, tubers, rhizomes runners, seeds etc. ) is highly successful
Temperature-Time combinations are to be standardized for each crop/material
Examples
HWT of bulbs of ornamental crops against Stem & Bulb nematode, Ditylenchus dipsaci
White tip disease of rice against white tip nematode, Aphelenchoides besseyi
Walia CCSHAU
3/31/2017

12. Chemical control Involves use of Nematicides or Nematocides
Pre-requisites
When Pi is very high
Crop is valuable
Quick results are warranted
Generally discouraged because of
Residue problems in edible parts
Environmental pollution
Toxicity to non-target organisms
Resurgence of pest problems
Cost considerations
Walia CCSHAU
3/31/2017

13. Classification of Nematicides
Fumigants
(Volatile halogenated hydrocarbons)
Non-Fumigants
Organocarbamates
Organophosphates
Walia CCSHAU
3/31/2017

14. Fumigants Highly volatile halogenated hydrocarbons
Upon application into soil, turn into gaseous phase and
diffuse through soil pore spaces
Kill nematodes due to blocking enzymes by substitution
with halogen moieties
Used extensively during s
Examples
DD – Dichloropropane and dichloropropene
EDB – Ethylene dibromide
MBr – Methyl bromide
1,3 D – 1,3 dichloropropene
DBCP - Dibromochloropropene
Walia CCSHAU
3/31/2017

15. Problems involved with Fumigants
Require high doses which are phytotoxic, hence need pre- plant application
Waiting period of 3-5 weeks
Need special applicators
Need soil surface sealing with covers
Need special field preparations
Efficacy dependant upon edaphic factors
Some proved carcinogenic and leave
residues in fruits
Walia CCSHAU
3/31/2017

16. Non-fumigants Advantages Effective against insects also
Effective at low dosages
Easy to apply and handle
Less phytotoxic an can be
applied to standing crops
Mostly systemic in nature
Relatively non-volatile
Walia CCSHAU
3/31/2017

17. Organophosphates Common name Trade name Organophosphates Ethoprop
Mocap
Fensulfothion
Dasanit
Phenamiphos
Nemacur
Phorate
Thimet
Thonazin
Nemaphos
Organocarbamates
Aldicarb
Temik
Carbofuran
Furadan
Metham Sodium
Vapam
oxamyl
Vydate
Walia CCSHAU
3/31/2017

18. Effect of Carbofuran against CCN in Wheat
Untreated
Carbofuran
Walia CCSHAU
3/31/2017

19. Economising Nematicidal Use
Seedling bare root dip treatment
Seed treatment
Coating, Dipping
Nursery bed treatment
Row treatment in widely spaced crops
Spot/basin area treatment in perennials
Walia CCSHAU
3/31/2017

20. Host Resistance Effective, Economical and Environmentally safe
Steps involved in breeding a disease resistant variety
Devising techniques for assessment of resistance
Screening of large germplasm, including wild species in some cases
Study of inheritance of resistance
Breeding resistant lines through cross/back cross, which have commercial traits
Rigorous testing under field conditions
Walia CCSHAU
3/31/2017

21. Nematode Resistant Crop Varieties
Resistant Variety
Nematode
Barley
C-164, Rajkiran, BH-75
Heterodera avenae
Wheat
Raj MR 1
Citrus
Trifoliate orange
Tylenchulus semipenetrans
Coffee
Robusta root-stock
Pratylenchus coffeae
Potato
Kufri Swarna
Globodera rostochiensis
G. pallida
Tomato
SL-120, PNR-7, Hisar Lalit, Karnataka Hybrid, Mangla Hybrid
Meloidogyne spp.
Cowpea
GAU-1
Walia CCSHAU
3/31/2017

22. Walia CCSHAU
3/31/2017

23. Regulatory Method - Quarantine
Legal enforcement to prevent introduction or check further spread of pests/diseases
Directorate of Plant Protection, Quarantine and Storage (Ministry of Agriculture, GOI), through DIP Act
International
Plant Protection Inspectors at all airports, seaports and landports for commercial material
Research material inspected by NBPGR, NBAGR
Domestic
Golden Nematode of Potato included in DIP Act 1971
Walia CCSHAU
3/31/2017

24. Biological Control
Classical biological control: Action of predators, parasites and pathogens to control pests
Ambit of biological control expanded now-a-days to include several other mechanisms, including antibiosis, host resistance etc.
Natural bio-control : Antagonistic
biotic interactions among co-habiting
natural populations of organisms
Introduced Biological Control
Inoculative release
Inundative release
Walia CCSHAU
3/31/2017

25. Nematode Antagonists Predators Collemboles Tardigrades Enchytreids
Protozoa
Predatory mites
Predacious nematodes
Mononchus
Seinura
Predacious fungi
Walia CCSHAU
3/31/2017

26. Predacious fungi Sticky hyphae : Stylopage Sticky knobs: Arthrobotrys
Examples
Sticky hyphae : Stylopage
Sticky knobs: Arthrobotrys
Non-constricting rings: Dactylella
Constricting rings: Dactylaria
Walia CCSHAU
3/31/2017

27. Parasites Fungi Egg parasites Female parasites Vermiform stages
Paecilomyces lilacinus
Pochonia chlamydosporia (Verticillium chlamydosprium)
Female parasites
Nematophthora gynophila
Vermiform stages
Catenaria
Walia CCSHAU
3/31/2017

28. Parasites
Bacteria
Pasteuria penetrans
Walia CCSHAU
3/31/2017

29. Other Antagonists Bacteria Pseudomonas fluorescens Bacillus subtilis
Azotobacter chroococcum
Glucoacetobacter diazotrophicus
Walia CCSHAU
3/31/2017

30. Integrated Nematode Management
INM seeks to stabilize pest nematode population below damaging levels (Pt) through integration of various unilateral and effective practices leading to a long-term package programme or schedule based on ecologically sound, economically viable and acceptable principles
Walia CCSHAU
3/31/2017

31. Walia CCSHAU
3/31/2017

32. Walia CCSHAU
3/31/2017