Sarah 51 Root knot disease of vegetables.pptx

Plant pathology

1. Root knot disease of vegetables Presented by : Sarah Ashfaq BSADP-BT51F21 BS 8 th 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 disease s ( 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 4 ( Li et al., 2015 )

5. Systematic Position Kingdom Animalia Phylum Nematoda Class Secernentea Order Tylenchida Family Heteroderidae Genus Meloidogyne 5

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.sciencedirect.com/topics/agricultural-and-biological-sciences/meloidogyne-javanica Figure D . N aturally infested root symptoms.  Meloidogyne javanica Source :https://www.researchgate.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.wikipedia.org/wiki/Meloidogyne_arenaria 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 . 7

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. 8

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 F orking 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.. 11

12. Symptoms Affected plants have an unthrifty appearance. Large galls S tunting W ilting C hlorosis (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 12

13. Symptoms: P atches of chlorotic Stunted N ecrotic Wilted plants . J K Source: https://ag.umass.edu/sites/ag.umass.edu/files/factsheets/pdf/nrkn_in_veg_crops_final-1.pdf Example: * Root Knot Disease on Pepper 13

14. Life Cycle 14

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 17

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/fpls.2021.800030/full 18

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, 19

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 (S uch 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) 20

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 21

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 agricult ural fields, at different locations in Lower Sindh and Hub, Balochistan wa s carried out in different seasons to determine the losses caused by soil-borne root-rotting fungi and root-knot nematodes in some economic crops. 22

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 23

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. 24

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 . 25

27. Thankyou الحمدالل ہ 26