Neem (नीम) is a Hindi noun derived from Sanskrit Nimba (निंब). Neem is a fast-growing tree that can reach a height of 15–20 metres (49–66 ft), and rarely 35–40 metres (115–131 ft). It is evergreen, but in severe drought it may shed most of its leaves or nearly all leaves The branches are wide and spreading. The neem tree is very similar in appearance to its relative, the Chinaberry

1. Submitted To: Dr. Sanjeev Ravi
Submitted By :
Vikas Tiwari (16031)
Diseases of Fruit, Plantation,
Medicinal and Aromatic Crops
(HPI 201)
Topic: Neem

2. Contents:-
 Introduction
 Medicinal Uses
 Leaf Web Blight
 Colletotrichum Leaf Spot and Blight
 Alternaria Leaf spot and blight
 Pseudocercospora Leaf spot
 Powdery Mildew
 Root Rot
 Other Foliar Diseases
 Latest news article on neem disease
 Research paper on leaf blight

3. NEEM
• B.N.: Azadirachta indica
• Kingdom:Plantae
• Clade:Angiosperms
• Clade:Eudicots
• Clade:Rosids
• Order:Sapindales
• Family:Meliaceae
• Genus:Azadirachta
• Species:A. indica

4. Introduction :
 Neem (नीम) is a Hindi noun derived from Sanskrit Nimba (ननिंब).
 Neem is a fast-growing tree that can reach a height of 15–20 metres (49–66 ft),
and rarely 35–40 metres (115–131 ft).
 It is evergreen, but in severe drought it may shed most of its leaves or nearly all
leaves
 The branches are wide and spreading.
 The neem tree is very similar in appearance to its relative, the Chinaberry

5. Medicinal Uses :
 Neem leaf is used for leprosy, eye disorders, bloody nose,
intestinal worms, upset stomach, loss of appetite, skin ulcers,
diseases of the heart and blood vessels (cardiovascular
disease), fever, diabetes, gum disease (gingivitis),
and liver problems.
 The bark is used for malaria, stomach and intestinal ulcers,
skin diseases, pain, and fever.

6.  The fruit is used for hemorrhoids,
intestinal worms, urinary tract
disorders, bloody nose, phlegm, eye
disorders, diabetes, wounds, and
leprosy
 Some people apply neem directly to
the skin to treat head lice, skin
diseases, wounds, skin ulcers; as a
mosquito repellent; and as a skin
softener.
 Neem is also used as an insecticide.
 https://www.theneemteam.co.uk/full-on-neem-and-coconut-cream.html

7. 1. Leaf Web Blight
Causal Organism :Rhizoctonia solani
Symptoms :
• Development of greyish brown blotches which increase in size with the advancing fungal hyphae
• Ultimately the entire leaf blade is affected.
• Infected adjoining leaves get joined together by the fungal hyphae as if caught in a spider’s
web, hence the name web blight.
• The leaflets or the entire pinnae become detached prematurely
• The disease spreads through contact of the overlapping foliage.
•https://www.theneemteam.co.uk.html

8. Control:
• The disease has been managed through interacted
approach which includes measures such as sanitation
and cultural practices.
• Application of fungicide (Bavistin 0.1% a.i.) is found
effective.

9. 2. Colletotrichum Leaf Spot and Blight
Causal Organism : Colletotrichum gloeosporioides.
It has been recorded in a serious form at New Forest, Dehra Dun. It appears in
nursery at the end of the September or first week of October (Mehrotra and
Pandey, 1992).
Symptoms :
• The fungus causes leaf spots which increase rapidly in size covering large leaf areas.
• The infected leaves present a blighted appearance and are eventually shed
• Severely infected seedlings show premature defoliation.
https://www.theneemteam.co.uk.html

10. Control:
• Application of Blitox fungicide (0.2% a.i.) twice
at weekly intervals is found effective in
controlling the disease.

11. 3. Alternaria Leaf spot and blight
Causal Organism : Alternaria alternata.
It is a destructive pathogen. It appears late in the growing season in the last
week of October or early November at New Forest, Dehra Dun (Mehrotra and
Pandey, 1992). It attacks the leaves when the leaves become old and contain
less soluble sugars.
Symptoms :
• The infection starts with the minute dots on the leaf with irregular chlorotic areas , then
circular to oblong concentric black velvety rings appear in the chloroted area.
•Then the lesions develop towards the base of the leaf. The spot join together and
spread quickly to the entire leaf area leading to blight.
https://www.extension.umn.edu/garden/yard-garden/trees-shrubs/management-of-leaf-spot-diseases

12. • Sometime a yellow hollow develops around each
lesion.
• As disease advances, spot size increases and complete
blightening takes place and leaves gradually die from
the tip downward.
Control:
• Application of Blitox fungicide (0.2%) at fortnightly
intervals is found very effective.

13. 4. Pseudocercospora Leaf spot
Causal Organism : Pseudocercospora subsessilis.
The disease occurs throughout the natural distribution of neem
Symptoms :
• The infection spots are brown in colour interspersed with white
patches.
• The fungus sporulates on the under surface of the leaf and
produces conidia which appear grayish in mass.
• The heavily infected leaves turn pale and are shed prematurely.
•https://www.extension.umn.edu/garden/yard-garden/trees-shrubs/management-of-leaf-spot-diseases

14. Control:
• Application of Mancozeb in combination with Brestan
is found effective in controlling the disease.
•crop rotation, and other cultural practices are also effective.

15. 5. Powdery Mildew
Causal Organism : Oidium azadirachtae.
Symptoms :
• White patches seen on the surface of the leaves.
• These patches coalesced and covered the whole leaf lamina
giving greyish white appearance.
• infection starts at the tip of the influorescence and spreads
downwards covering the floral axis

16. Control:
• Foliar spray of Bavistin fungicidal solution (0.01%) is
found to be effective in minimizing the disease.
•Sulphur based fungicide or sulphax @0.2% or
wettable sulphur @ 0.3%
•Kelathane @ 0.4%

17. 6. Root Rot
Causal Organism : Ganoderma lucidum
Symptoms :
• Yellowing of lower leaves which gradually progresses upwards followed by
drooping of branches .
• Infected leaves bend or fall down.
• Longitudinal cracking can be seen through these cracks, gummy oozing
appear which results in mushroom like basidiocarp formation.
• Root rotting is common after the death of the infected tree.
•http://valuetreeservice.com/guard-your-trees-from-root-rot/

18. Control:
• Maintain Proper plant density
• Application of clay soil
• Summer irrigation
• Root feeding with Calixin @ 20 ml/100 ml of water
• Remove and burn severely affected plants
• Apply Trichoderma spp. to the soil

19. Other Foliar Diseases
1. Bacterial leaf spot : Bacterial leaf spot is caused by a bacterium,
Xanthomonas azadirachtii and Pseudomonas viticola.
2. Leaf spot and Blight : Leaf spot is caused by Colletotrichum capsici. Leaf
Blight and stem rot are caused by Sclerotium rolfsii.
3. Seedling Wilt : Seedling wilt is caused by Fusarium solani. Twig canker and
shot hole in leaves are caused Phoma sp.

20. Leaf blight of Azadirachta indica and its management in
vitro A. Bhanumathi and V. Ravishankar Rai
 a moderate to severe foliar disease of Azadirachta indica was
caused by Colletotrichum dematium and Fusarium solani. Previously
F. solani was reported on neem but the presence of C. dematium is a
new document.
 F. solani was highly virulent against seedlings of neem compared to
C. dematium in seeds subjected to top of the paper method.
 In vitro management of these pathogens using Poison Food
Technique suggested that of the seven fungicides tested at 50, 100
and 150 ppm concentrations, 100% growth inhibition was recorded in
all the three concentrations and Tilt against C. dematium
Research paper on leaf blight:-

23. Refrences
 http://agritech.tnau.ac.in/forestry/forest_disease_neem.html
 https://www.forestryimages.org/collections
 http://www.academicjournals.org/article/article1380879050_Bhanumathi%20and%20R
ai.pdf – (Research paper on leaf blight)
 SUBHERWAL. SUHANI, NEEM , June 2010 ,Bishan singh mahendra pal singh ,vol 1
 Thakur R. S., PURI H. S., HUSSAIN AKHTAR, (1989) , MAJOR MEDICINAL PLANTS IN
INDIA. VAP INTERPRISES , pp. 85-87
 http://www.finegardening.com/control-pests-and-diseases-safely-neem
 http://www.alamy.com/stock-photo/neem-leaves-and-twigs.html
 http://www.newindianexpress.com/cities/bengaluru/2017/jul/30/fungal-disease-threatening-
neem-trees-across-city-1635680.html -(news on fungal disease in neem)

24. Thank you