General Symptoms of Plant Disease: Plant Pathology Notes || Crop Diseases and Their Pathogen Names: Agricultural Plant Pathology

                

General Symptoms of Plant Disease: Plant Pathology Notes

1. Necrosis:- Death of cells, tissues and organs caused by pathogen. e.g. - Spots, blights, canker, streaks, damping-off etc.

2. Wilt:- Drying and drooping of plant organs due to loss of turgidity. Wilting takes place due to blockage in the translocation system caused by the pathogen.

3. Die-back:- Drying of plant organs like twigs or branches from the top to downward.  

4. Mildew:- White, grey or brown coloured superficial or powdery growth of the pathogen on the host surface is called mildew.  It is two type-

(a). Downy Mildew:- Downy feather like growth on the lower surface of the leaf, is called Downy Mildew.

(b). Powdery Mildew:- Dusty or powdery growth of fungus on the upper surface of the leaf, is called Powdery Mildew.

5. Rusts:- Several small pustules emerges out through breaking the host epidermis which gives rusty appearance of the affected parts.  

6. Smuts:- Sooty or charcoal like powder. Affected plant organs gives appearance of a black or purplish black dusty-mass composed of fungus spores.

7. Blotch:- A large area of discolouration of a leaf, fruit etc. giving a blotchy appearance. 

8. White blisters:- Several white, blister like pustules emerges out by breaking the host surface and expose white powdery mass of spores. It is common in Cruciferous plants.

9. Colour change:- It indicates conversion of green pigment of leaves into other colours mostly to yellow colour, in patches or covering the entire leaves. 

(i) Etioliation:- Yellowing of plant organs due to lack of sunlight.

(ii) Chlorosis:- Yellowing of plant organs due to infection caused by viruses, bacteria, fungi, low temperature or deficiency of nutrients etc.

(iii) Chromosis:- Conversion of green pigment of plant organs into red, purple or orange colours.

(iv)  Albino:- Lack of any pigment and plant organs turned into white coloured. 

10. Exudation:- Mass of bacterial cells ooze out at surface of the affected plant organ and from some drops or smear, is called Exudation.

11. Overgrowth:- Excessive growth of the plant parts due to infection by pathogens.  

Overgrowth is two types:-

(a). Hyperplasia:- Abnormal increase in size of plant parts due to excessive rate of cell division.

(b). Hypertrophy:- Abnormal increase in size or shape of plant organ due to excessive enlargement of the size of cells.  

12. Atrophy:- It is phenomenon in which plant growth is inhibited due to decrease rate of cell division or reduction in cell size.

13. Sclerotia:- These are dark and hard structures of various shaped composed of dormant mycelia of some fungi. 

14. Scab:- A roughened or crust-like lesion appearance at infected plant organ. It is most common in Apple and Potato etc.

15. Phyllody:- Transformation of floral parts into green leafy structures. It is common in Sesame. 

16. Anthracnose:- Dark ulcer like lesions on the infected plant parts. 

17. Damping Off:- Destruction or rotting of seedling near the soil surface, which cause falling of seedling on the ground.

18. Gummosis:- Production of gum by plant tissues caused by Pathogens.

19. Gall:- A swelling produced on plant results of infection caused by some plant pathogens.

20. Mosaic:- Alternate pattern or intermingled patches of light green and yellow color.

Crop Diseases and Their Pathogen Names: Agricultural Plant Pathology

🔹DISEASES OF RICE

(1). Rice blast - Pyricularia oryzae

(2). Rice brown leaf spot - Helminthosporium oryzae

(3). Narrow brown leaf

spot of rice- Cercospora oryzae

(4). Rice sheath blight - Rhizoctonia solani

(5). False smut of rice - Claviceps oryzae-sativae

(6). Stem rot of rice - Sclerotium oryzae

(7). Sheath rot of rice - Sarocladium oryzae

(8). Bacterial leaf blight - Xanthomonas oryzae pv. oryzae

(9). Bacterial leaf streak - Xanthomonas campestris p.v. oryzicola

(10). Tungro disease - Rice Tungro Bacilliform Virus (RTBV)

Rice Tungro Spherical Virus (RTSV)

Vector - Green Leaf Hopper (Nephotetix virescence)

🔹DISEASES OF WHEAT AND BARLEY

(1). Black or stem rust - Puccinia graminis tritici.

(2). Leaf, brown or orange rust -Puccinia recondita

(3). Yellow or stripe rust - Puccinia striformis

(4). Loose smut - Ustilago nuda tritici

(5). Karnal bunt - Neovossia indica

(6). Leaf blight - Alternaria triticina

(7). Tundu disease or yellow slime

disease - Anguina tritici (Nematode) +Corynebacterium tritici or

Clavibacter tritici

(8). Powdery Mildew - Erysiphe graminis tritici

(9). Flag Smut - Urocystis tritici

(10). Hill Bunt - Tilletia foetida

(11). Covered Smut of Barley - Ustilago hordei

(12). Loose Smut of Barley - Ustilago nuda

(13). Powdery Mildew of Barley - Erysiphe graminis var. hordei

🔹DISEASES OF SORGHUM

(1). Ergot or sugary disease - Sphacelocia sorghi

(2). Anthracnose or red leaf spot -Colletotrichum graminicola

(3). Rust -Puccinia purpurea

(4). Leaf blight or leaf stripe -Trichometasphaeria turcica

(5). Grain smut/Kernel smut -Sphacelotheca sorghi. 

(6). Downy Mildew or Leaf shredding - Peronosclerospora sorghi

(7). Leaf Rust - Puccinia purpurea

(8). Long Smut - Tolyposporium ehrenbergii

🔹DISEASES OF PEARLMILLET

(1). Downy Mildew/ Green Ear Disease - Sclerospora graminicola

(2). Ergot of Bajra - Claviceps fusiformis

(3). Smut of Bajra - Tolyposporium penicillariae

🔹DISEASES OF MAIZE

(1). Turcicum Leaf blight -Helminthosporium turcicum. 

(2) Cephalosporium wilt - 

Cephalosporium maydis

(3). Charcoal rot - Macrophomina phaseolina.

(4). Banded leaf and sheath

blight- Rhizoctonia solani. 

(5). Seedling Blight - Pythium aphanidermatum

(6). Smut of Maize - Ustilago maydis

🔹DISEASES OF SUGARCANE

(1). Red Rot - Colletotrichum falcatum

(2). Grassy Shoot of Sugarcane - Phytoplasma

(3). Smut - Ustilago scitaminea

(4). Ratoon Stunting Disease of Sugarcane - Clavibacter xyli sub sp. xyli

(5). Red Stripe - Xanthomonas rubrilineans

(6). Pineapple Disease/ Sett Rot - Ceratosystis paradoxa

🔹DISEASES OF POTATO

(1). Early Blight - Alternaria solani

(2). Late Blight - Phytophthora infestans

(3). Scab - Streptomyces scabies

(4). Black Scurf - Rhizoctonia solani

(5). Wart - Synchytrium endobioticum

🔹OTHER CROP DISEASES

(1). Fusarium Wilt of Gram - Fusarium oxysporium f. spp. ciceri

(2). Ascochyta Blight of Gram - Ascochyta rabiei

(3). Fusarium Wilt of Pigeon Pea - Fusarium oxysporium f. spp. udum

(4). Sterility Mosaic - Viral disease 

Vector - Eriophyid Mite (Aceria vajani)

(5). Tikka Disease of Groundnut - Cercospora personata and Cercospora arachidicola

(6). Collar rot disease of Groundnut - Aspergillus niger

(7). White Rust of Crucifers - Albugo candida

(8). Alternaria Blight of Crucifers - Alternaria brassicae

(9). Phomopsis Blight/Fruit Rot of Brinjal - Phomopsis vexans

(10). Little leaf of Brinjal - Phytoplasma

(11). Anthracnose/Ripe Rot/Die Back of capsicum - Colletotrichum capsici

(12). Club root of Crucifers - Plasmodiophora brassicae

DISEASES OF FRUIT CROPS

(1). Panama wilt - Fusarium oxysporium var. cubense

(2). Bunchy Top - Viral disease

Vector - Pentolania nigronerversa 

(3). Citrus Canker - Xanthomonas compestris p. Var. citri

(4). Die- back/ Wither tip of Citrus - Colletotrichum gloeosporioides

(5). Gummosis of Citrus - Phytophthora palmivora

(6). Greening Disease of Citrus 

Candidatatus liberobacter

(7). Tristeza of Citrus - Viral disease

Vector - Toxoptera citricida

Note:- All the pictures included in the blog have been taken from the various internet sources. All the right of the pictures are secured to their owners. Pictures are only used here for the fair use of content for educatioal purpose.

Note:- All the pictures included in the blog have been taken from the various internet sources. All the right of the pictures are secured to their owners. Pictures are only used here for the fair use of content for educatioal purpose.

Thank You

Vikas Kashyap:)

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