Presiding Officer Training module 2024 lok sabha elections
Sarah 51 Root knot disease of vegetables.pptx
1. Root knot disease of vegetables
Presented by : Sarah Ashfaq
BSADP-BT51F21
BS 8th Semester ADP Replica
Presented to: Dr. Najam ul Sehar
Institute of Botany, University of the Punjab
1
2. Contents
Introduction
General characteristics
Systematic position
Species Diversity
Symptoms
Life cycle
Infection and spread
Economic importance
Control
Work in Pakistan
Conclusion
References
2
3. Introduction
Nematodes are a very varied group of invertebrates. They are
particularly common as freeliving saprotrophic species in the soil,
around plant roots, on dung and in all kinds of decomposing plant
matter, as well as in freshwater and marine habitats. Sedentary
species form adult stages inside plant root tissues where they cause
the economically important root knot diseases (Meloidogyne spp.)
Root-knot nematodes are a growing concern for vegetable
producers, because chemical nematicides are gradually disappearing.
3
4. General characteristics of Nematophagous fungi
Cosmopolitan
microorganisms
Natural
antagonists of
nematodes
Classified into
four groups
Modified
hyphae
Occur in
natural and
agricultural
soil
No. of species
( 700 ).
4
(Li et al.,
2015)
6. Figure A. Tomato roots
infested by Meloidogyne
incognita root-knot
nematodes.
Source: Courtesy Scot
Nelson at University of
Hawaii.
Figure B. Galls of
northern root-knot
nematode Meloidogyne
hapla.
Source:https://www.scien
cedirect.com/topics/agric
ultural-and-biological-
sciences/meloidogyne-
javanica
Figure D. Naturally infested
root symptoms.
Meloidogyne javanica
Source:https://www.resear
chgate.net/figure/A-
Esterase-phenotypes-of-
Meloidogyne-javanica-MJ-
as-standard-J3-and-M-
incognita_fig2_317573174
Figure A. Meloidogyne
arenaria on Beta
vulgaris (beetroot)
Source:https://en.wikiped
ia.org/wiki/Meloidogyne_a
renaria
Species diversity
A B C D
6
7. Source: A survey of okra (Abelmoschus esculentus) in the Punjab province of Pakistan for the
determination of prevalence, incidence and severity of root-knot disease caused by Meloidogyne
spp. Pakistan Journal of Botany, 44(6), 2071-2075.
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8. Symptoms:
Nematodes cause galls (knots) to form on both roots and pods, these
galls are highly diagnostic for root-knot nematode presence compared
to other nematodes affecting peanut.
Affected plants have an unthrifty appearance and often show symptoms
of stunting, wilting or chlorosis (yellowing).
Symptoms are particularly severe when plants are infected soon after
planting.
Swellings or nodules on plant roots can indicate root-knot nematodes.
Affected plants produce fewer and smaller fruit.
Root crops such may be deformed or have hairy roots with nodules.
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9. Symptoms
• Due to of the presence of gall or
knots on the roots the root-knot
disease of tomato is very
distinctive.
• Foliage colour paler than normal.
• Plant remain-stunted and wilting is
caused.
Examples: *Root Knot Disease of Tomato
Pathogen Meloidogyne javanica (Treub.)
Chitwood
Source: Akhtar, M. (1997) Biological control of plant parasitic
nematodes by neem products in agricultural soils. Applied Soil
Ecology 7: 219-223
E
9
10. Example: *Root Knot Disease of Brinjal
Symptoms
• Tiny tubercles.
• The plants develop slowly and appear stunted.
• The main roots and the laterals in all cases
bear spherical to elongated galls.
Pathogen : Meloidogyne sp
Source: Akhtar, M. (1997) Biological control of plant parasitic nematodes by neem
products in agricultural soils. Applied Soil Ecology 7: 219-223
F
10
11. Example: *Root Knot Disease of Carrot
Symptoms
• Galls on carrot feeder roots
• Forking
• Stunting and yellowing of
plants
Figure G. On left stunted
and forked carrots.
Photo: S.A. Johnson,
Rutgers
Figure H. The galls can also
merge to form large galled
area throughout the feeder
roots.
G H
Source:
https://plantpath.ifas.ufl.edu/u-
scout/carrot/root-knot..
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12. Symptoms
• Affected plants have an
unthrifty appearance.
• Large galls
• Stunting
• Wilting
• Chlorosis (yellowing)
Figure I: Large galls and swollen root system caused
by the peanut root-knot nematode.
I
Example: *Root Knot Disease of Peanut
Source:
https://extension.umd.edu/resource
/root-knot-nematodes-vegetables
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13. Symptoms:
• Patches of chlorotic
• Stunted
• Necrotic
• Wilted plants.
J K
Source:
https://ag.umass.edu/sites/ag.umass.edu/files/factsheets/pd
f/nrkn_in_veg_crops_final-1.pdf
Example: *Root Knot Disease on Pepper
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15. Figure I: Disease cycle of root knot caused by nematodes
of the genus Meloidogyne.
15
I
16. 16
Source: Kavitha, P. G., Jonathan, E. I., & Nakkeeran, S. (2011). Life cycle, histopathology and yield loss caused by root
knot nematode, Meloidogyne incognita on Noni. Madras Agricultural Journal, 98(10-12), 386-389.
J
17. FIGURE K. Stages in the life cycle of
the root-knot nematode. (A) Nematode
egg with second-stage juvenile ready to
hatch. (B) Second-stage juvenile
penetrating root tissues. (C) Female
root-knot nematode in plant root causing
the formation of and feeding on “giant
cells.” (D) Longitudinal section
of Meloidogyne female feeding on giant
cells. (E) Root-knot female laying eggs
outside the root.
SOURCE:
[Photographs courtesy of (A) D. W.
Dickson, (B) USDA, and (C–E) R. A.
Rohde.
K
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18. Figure L. The first illustration of root-knot nematodes on
plant roots. A: galled roots; B: section through gall,
showing nematodes and eggs. After Berkeley (1855).
L
Figure M. Root-knot nematode infection and
glands involved in effector synthesis
M
Source:
https://www.frontiersin.org/articles/10.3389/f
pls.2021.800030/full
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19. Infection and spread
Nematodes are most common and introduced into a new paddock or
area by planting seedling, tumors or young plants that are already
infected with root knot.
It can also be spread to a new area by running water, cultivation tools,
machinery, animals and footwear.
Without the help of these distributing agents, spread is only a few
centimetres each year within a paddock,
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20. Economic Importance
In Lettuce and carrots intitial density 1 and ≤ eggs / cc soil respectively are sufficient
to cause economic losses.
Vegetable crops grow in warm climates can causes severe losses from root knot
nematodes.
Meloidogyne occurs in 23 of 43 crops have plant parasitic nematodes having
importance ranging from field crops, grasses, horticultural, ornamented and vegetable
crops.
Nematode demaged roots use water and fertilisers leading to losses for the grower.
21. Control:
Cultural control
Cover crops (Such as sudangrass and marigolds actually produce
chemicals that are toxic to nematodes).
Chemical Control
Fumigants (such as 1,3-dichloropropene, methyl bromide and
dazomet)
Nervous system toxins ( e.g including oxamyl)
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22. Biological control
By treating nematode infested soil with endospore of bacterium
Pasteuria penetrans, it is an obligate parasite of some plant
parasite of some plant parasitic nematodes or with the preparation
of the fungus Trichoderma.
By treating transplant or infested soils with spores of the fungus
Dactyella oviparasitica which parasitize the egg of Meliodyne.
By treating transplant or infested soil with the spores of the
vasicular arbuscular mycorrhizal fungi. E.g Glomous
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23. Work in Pakistan:
Soil-borne plant diseases caused by root-knot nematodes is a serious
threat to modern agriculture.
In Pakistan, no extensive research work has been done on crop
losses estimation by these pathogens and pests.
During the present study, survey of diseased agricultural fields, at
different locations in Lower Sindh and Hub, Balochistan was
carried out in different seasons to determine the losses caused by soil-
borne root-rotting fungi and root-knot nematodes in some economic
crops.
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24. • Chili (Capsicum annuum L.)
• Cotton (Gossypium hirsutum L.)
• Egg-plant (Solanum melongena L.)
• Melon (Cucumis melo L.)
• Sunflower (Helianthus annuus L.)
• Tomato (Lycopersicon esculentum)
• Watermelon (Citrullus lanatus ).
• The most common
root rot pathogens
found in all the areas
visited were
Macrophomina phaseolina,
Rhizoctonia solani and
Fusarium.
Source: Parveen, G., Urooj, F. A. I. Z. A. H., Moin, S. H. U. M. A. I. L. A., Farhat, H. A. F. I. Z. A., Fahim, M. F., & Ehteshamul-Haque, S. (2020).
Estimation of losses caused by root rotting fungi and root knot nematodes infecting some important crops in lower sindh and hub, balochistan of
Pakistan. Pak. J. Bot, 52(2), 673-678.
Work in Pakistan
Examples
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25. Conclusion
Most root-knot nematodes also have extremely wide host ranges. Although
it is difficult to ascertain the number of hosts for any one root-knot
nematode species, it is likely that some root-knot nematodes can survive
on hundreds of different plant species.
Severe infections result in reduced yields on numerous crops and can also
affect consumer acceptance of many plants, including vegetables.
Cultivation and other practices that physically move soil and plants will
rapidly spread root-knot nematodes.
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26. References
Monfort, W. S., Csinos, A. S., Desaeger, J., Seebold, K., Webster, T. M., & Diaz-Perez, J. C. (2007).
Evaluating Brassica species as an alternative control measure for root-knot nematode (M. incognita) in
Georgia vegetable plasticulture. Crop Protection, 26(9), 1359-1368.
Collange, B., Navarrete, M., Peyre, G., Mateille, T., & Tchamitchian, M. (2011). Root-knot nematode
(Meloidogyne) management in vegetable crop production: The challenge of an agronomic system
analysis. Crop protection, 30(10), 1251-1262.
Sasser, J. N. (1977). Worldwide dissemination and importance of the root-knot nematodes,
Meloidogyne spp. Journal of Nematology, 9(1), 26.
Olsen, M. W. (2011). Root-knot nematode.
G., Urooj, F. A. I. Z. A. H., Moin, S. H. U. M. A. I. L. A., Farhat, H. A. F. I. Z. A., Fahim, M. F., &
Ehteshamul-Haque, S. (2020). Estimation of losses caused by root rotting fungi and root knot
nematodes infecting some important crops in lower sindh and hub, balochistan of Pakistan. Pak. J.
Bot, 52(2), 673-678.
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