Fungal diseases of fruit crops banana

Some fungal diseases of banana

1. Fungal diseases of Fruit crops-Banana Vaishali S.Patil Assosiate Professor, Department of Botany Shri Shivaji College of Arts, Commerce & Science Akola

2. 1. Anthracnose and Fungal scald and Stem-end rot caused by Colletotrichum musae Symptoms- At the initial stage, small, circular, black spots develop on the affected fruits. Then these spots enlarge in size, turn to brown colour. The skin of the fruit turns black and shrivels and becomes covered with characteristic pink acervuli . Finally the whole finger is affected. Later the disease spreads and affects the whole bunch. The disease results in premature ripening and shriveling of the fruits which are covered with pink spore masses. Sometimes the main stalk of the bunch may become diseased. Infected fruits become black and rotten. Control- Fungicides

3. 2.Armillaria corn rot caused by Armillaria mellea , Armillaria tabescens Symptoms-  plants slowly decline, leaf yellowing, reduced leaf growth and twig dieback. presence of cream-coloured fungal growth, sometimes fan-shaped, just beneath the bark of the crown and large roots, and a strong mushroom smell. Black, cord-like threads of the fungus often occur on the surface of the roots, forming a branched network that may extend 200-300 mm into the soil. Honey-coloured mushrooms with widely separated gills can form at the base of an affected tree during wet, cold weather in early winter. Control- Prepare soil thoroughly, remove as many roots and stumps as possible before planting, use resistant rootstocks, Fumigate infested soil, fungicides.  

4. 3.Black cross caused by Phyllachora musicola Symptoms- The spots are black, four-pointed stars, most clearly seen on the lower surface of older leaves. The long axis of the star is parallel to the leaf veins, that is, at right angles to the length of the leaf. The spots are scattered, but sometimes occur in large groups.A velvet-like mass of spores is produced on the lower surface of the spots. Control- reducing shade levels or planting the bananas in open ground, resistant varieties, fungicides.

5. 4 .Black leaf streak (BLS) or Black Sigatoka and Septoria leaf spot , Yellow Sigatoka caused by Mycosphaerella fijiensis , Pseudocercospora ( Paracercospora ) fijiensis , Mycosphaerella eumusae , Septoria eumusae , Mycosphaerella musicola Symptoms- Early symptoms appear on the third or fourth leaf from the top, i.e., on young leaves. Small spindle shaped spots on foliage with greyish centre and yellowish halo running parallel to veins.If the fruit is nearing maturity at the time of heavy infection, the flesh ripens but evenly and individual bananas appear undersized and their flesh develops a buff pinkish colour, and store poorly. Control- fungicide.

6. 5 .Black root rot caused by Rosellinia bunodes Symptoms-  Brown lesions on roots that progressively darken to black. Dark discoloration of vascular bundles is visible shortly thereafter. Once inside the vascular tissue,  compromises xylem flow and transport of nutrients to aerial parts of the host resulting in  chlorosis , wilting, dry die-back, leaf drop, and eventually host death. White, cottony growth on roots that also progressively darken with age.As mycelia grow, they form dense mats over roots and at the base of tree trunks that thicken into irregular knots and aggregate into  rhizomorphs . Over time mycelia darken to form black, branching strands firmly attached to host roots; occasionally black dots are visible before this color change. Control- Good soil drainage and appropriate soil fertility, removal of crop residue,  fungicide, crop rotation, soil solarization . 

7. 6 .Brown blotch caused by Pestalotiopsis leprogena Symptoms- Occur on leaf blade (leaflets or leaf segments) or only the petiole and rachis; or, it can develop on both tissues at the same time. Spots will begin as very small yellow, brown or black spots.  the spots may expand and increase in number until they merge (coalesce) to form a leaf blight or rachis blight (larger area of affected tissue). Often, the spots turn a grayish color that are outlined in black. The same type of lesions occurs on the petiole or rachis   Control- sanitation and water management , diseased leaves should be pruned and destroyed,  fungicides

8. 7 .Brown spot caused by Cercospora hayi Symptoms- lesions occurs on the fruit, stalk, crown cushion, and fingers. The spots are dark brown, have an irregular margin, and are surrounded by a halo of water-soaked tissue   Control- Plantation sanitation, good drainage and proper spacing,  fungicides.

9. 8.Ceratocystis fruit rot and Main stalk rot caused by Ceratocystis paradoxa , Chalara paradoxa Symptoms- black end and finger-tip rot symptoms are produced. black lesions on the fruit is the main infection part of the plant. If the pathogen infects the plant while fruits are still on it, they will prematurely drop. Discoloration of leaves as well as the seeds also take place. The lesions on the fruit evolve to become soft rot spots that produce a heinous odor . The fruit can even get to the point of breakdown. Control- Heat Treatment , hot-water treated,  fungicide .

10. 9.Cigar-end / Verticillium tip rot and Trachysphaera finger rot caused by Verticillium theobromae , Trachysphaera fructigena Symptoms- Attack ripening fruit causing a dry rot of the flower end that produces an ash grey wrinkled lesion similar to the burnt end of a cigar. Rotting occurs causing a black wrinkled necrosis with the fruit eventually becoming mummified Control- sanitation and avoiding damage to host tissues, deflowering and bagging of maturing banana stems,  fungicide

11. 10.Cladosporium speckle caused by Cladosporium musae Symptoms- Pale greenish flecks, ellipsoid to oblong, forming streaks, pale to blackish brown, turning orange or dark brown, merging and forming large patches, occasionally somewhat target-like.  Control- Reduce plant density to lower leaf infection, Collect, remove and destroy heavily speckled leaves from plants, Remove shade and weeds, desucker plants, fungicides

12. 11.Corm dry rot caused by Junghuhnia vincta Symptoms- Yellowing and browning of foliage with older foliage dying first. Some branches affected before others, giving tree crowns an uneven, patchy appearance .  Small pads of white or pale pink fungal tissue develop at the base of the tree, and on roots just below the soil surface. Fruiting bodies in the form of pink encrustations with pores may develop on the lower stem.  Control-  Improved/resistant cultivars and disease free planting stocks, judicious use of pesticides, irrigation water, removal of diseased plants and plant parts, proper sanitation in plantation. 

13. 12.Cordana leaf spot caused by Cordana johnstonii , Cordana musae Symptoms- On the leaf large, pale brown, oval to fusiform necrotic lesions with pale grey  concentric ring patterns, with a dark brown border surrounded by a bright yellow halo separating are found.Often , lesions coalesce into large necrotic patches. The leaves ultimately turn brown and  dry out. Control- fungicides.

14. 13.Crown rot and Peduncle rot caused by Fusarium pallidoroseum , Colletotrichum musae , Verticillium theobromae , Fusarium  spp ., Acremonium  spp . Lasiodiplodia theobromae Symptoms- Blackening and softening of tissues and begins at or near the cut surface of the crescent-shaped crown where the hand is detached from the main fruit stalk. The fungus also extends through cushions and causes finger stalk rot and finger dropping. The skin becomes soft, black, wrinkled and encrusted with pycnidia . Infection may lead premature ripening of the fruits. Control- fungicides, avoid and injury to the fruits, use of resistant varieties, storage of fruits at 100 C.

15. 14.Cylindrocladium root rot caused by Cylindrocladium   spp . Symptoms- Chlorotic lower leaves and a wilted appearance, onto leaves, dime sized circular brown necrotic lesions surrounded by yellow halos will eventually form on leaves.Reddish -brown lesions can be found on root. These lesions grow rapidly causing total root collapse and rot.  Control- fungicide, removal of infected plants.

16. 15.Damping-off caused by Deightoniella torulosa Symptoms- On leaves lesions were tan to black. However, larger oval black lesions with yellow halos also occurred. Lesions were more prevalent on older leaves. On young leaves, lesions first appeared along the leaf margin near the tip of the leaf on one side of the central vein. Lesions expanded to the entire leaf as the disease progressed, but were more prevalent along leaf margins. Control- fungicide

17. 16.Deightoniella fruit speckle, leaf spot and tip rot caused by Deightoniella torulosa Symptoms- On the leaves, it causes oval, tan spots with a black border, usually on the older leaves . On the fruit, sunken dark brown or black spots, surrounded by a dark green halo. Spotting of the fruit is greatest towards the tips of the fingers. The fungus does not produce spores on the fruit. The fungus also attacks the flower parts. Control- Remove dead or dying leaves , fungicides

18. 17.Diamond spot caused by Cercospora hayi , Fusarium   spp Symptoms- The spots are oval to diamond-shaped, and at right angles to the length of the leaf . They are brown on the upper surface, zoned, with yellow margins, and grey to brown below. The spots often merge, covering large areas of the leaf; this occurs particularly at the margin of the leaf giving a band of dead tissue with a zigzag yellow border between diseased and healthy parts. Some time the spots appear greyish-brown and hairy. Control- Resistant varieties, fungicides.

19. 18.Dwarf Cavendish tip rot caused by Nattrassia mangiferae =  Hendersonula toruloidea Symptoms- Lodging, partial or complete wilting of the plant, and rotting (dry or soft) of roots. It also cause pit canker and spot on the stem of plants or fruits, as well as internal black rot of fruits, Control- fungicides.

20. 19.Eyespot and Leaf spot caused by Drechslera gigantea , Drechslera musae-sapientum Symptoms-  mature lesion has a white or grey centre and a narrow, well‐defined, brown border.  Control- Provide good drainage, Aerate to eliminate soil compaction, Avoid herbicide applications, Water adequately, but not excessively, fungicide.

21. 20.Fruit freckle (freckle ) caused by Guignardia musae , Phyllosticta musarum Symptoms- Spots clustering in lines running horizontally across leaf which down veins of leaf. Dense aggregations of spots cause black blemishes on skin of fruit. Although detracting from the appearance of the fruit, the eating qualities are not affected. Control- cutting out infected leaves, the paper bag method, fungicide application, and proper sanitation techniques.

22. 21.Fruit rot caused by Botryosphaeria ribis Symptoms- elongated black spots and the entire fruit became rotten. Control- Soil treatment involving fumigation, soil solarization or sanitation, Soil preparation, fungicide

23. 22.Fungal root-rot caused by Fusarium solani , Nectria haematococca , Fusarium oxysporum , Rhizoctonia  spp. Symptoms- Wilting, stunting and chlorosis or lesions on the stem and/or leaves.Narrow , long, red to brown lesions on the stems, and lengthwise cracks often develop.  Lesions extend down the main taproot, which may shrivel, decay and die. Control-  crop rotation and timing of planting, resistant varieties. 

24. 23.Leaf rust caused by Uredo musae , Uromyces musae Symptoms- Dark brown to black streaks appear on the leaves, often surrounded by yellow halos. The streaks are more numerous on the lower surface of the leaves. They are slightly raised, and feel rough to the touch due to the spore masses of the fungus. If the disease is severe, the leaves may turn yellow. Mainly the older leaves are affected. Control- fungicides.

25. 24.Leaf speckle caused by Acrodontium simplex Symptoms- The lesions first appear as brown to dark brown tiny specks with elongate into black fine streaks parallel to the veinlets . The affected areas become necrotic and the infected leaves eventually die. Control- fungicides

26. 25.Leaf spot caused by Curvularia eragrostidis Symptoms- leaf spot starts as very small round tan lesions on leaves. Lesions often have a brown border and can be surrounded by a yellow halo . A few lesions scattered across leaves to lesions densely covering large sections of leaves. Symptoms can be observed at any growth stage. Control- residue decomposition, crop rotating, hybrid resistance.

27. 26.Leaf spot caused by Leptosphaeria musarum Symptoms- Light greenish-brown, somewhat indistinct, narrow streaks or less in diameter. The brown stage, in which the spot expands laterally to become elliptical and turns first light and then dark brown to almost black; the leaf has dried out at severity. the grey centre stage, in which the elliptical lesion dries out to a light grey, with the bases of the old fructifications showing up as scattered black dots. Control- fungicides

28. 27.Leaf spot caused by Pestalotiopsis disseminata Symptoms- small yellow, brown or black discoloration of the leaves. The disease can be restricted to the leaf blade or may only appear on the petiole and rachis right away. The spots will often turn a grayish color and will be outlined in black. Extreme wilting and a drying appearance on the leaves. Control-  sanitation and irrigation management,  Wounds and damage to the plan, eliminating overhead irrigation, Nutrient management, pruning the leaves, fungicides.     

29. 28.Malayan leaf spot caused by Haplobasidion musae Symptoms- diamond-shaped, greyish-white spots on the upper leaf surface. The spots, which sometimes have brown centres, were surrounded by a black border. On the undersurface of the leaf, the lesion could be covered with a dense, velvety brown mass (Water-soaked areas, often several times the size of the spot, have been observed surrounding lesions . The lesions were often pale on the upper leaf surface and darker on the lower surface, with dark purple borders. Control- reduce shade and humidity levels

30. 29.Marasmiellus rot caused by Marasmiellus inoderma =   Marasmius semiustus Symptoms- Rotted patches on rhizome and pseudo stem, gradual wilting of leaves from lower area to upper part, diminutive growth, strange foliage and bunches, toppling of crown, fruiting body adhere on pseudo-stem are the major syndromes of disease Control- Fungicides

31. 30.Panama disease ( Fusarium wilt ) caused by Fusarium oxysporum f.sp . cubense Symptoms- Yellowing of the lower most leaves starting from margin to midrib of the leaves. Yellowing extends upwards and finally heart leaf alone remains green for some time and it is also affected.The leaves break near the base and hang down around pseudostem . Longitudinal splitting of pseudostem . Discolouration of vascular vessels as red or brown streaks. Control- use of soil fumigants, sanitation, resistant varieties, Crop rotation, Fungicides.

32. 31.Pestalotiopsis leaf spot caused by Pestalotiopsis palmarum Symptoms- Water-soaked symptoms appeared first. The infected site developed into a black–brown lesion. In the later stage of infection, the diseased area turned into an elliptical or irregular shaped grey lesion with a golden yellow margin. Control- fungicides.

33. 32.Phaeoseptoria leaf spot caused by Phaeoseptoria musae Symptoms- small necrotic, lentis shape and dark brown spots similar Sigatoka symptoms, which soon later enlarge rapidly and become rot. Control- fungicides.

34. 33.Pitting caused by Pyricularia grisea Symptoms-  Blast lesions on young leaves, transition leaves, mid rib, petioles, peduncle, maturing bunches, bunch stalks and cushions. The distinct small pitting spots on maturing bunches reduced the visual appeal of mature fruits. Appearance of pitting symptoms on fruits in relation with age of fruits and their distribution pattern on bunch and fingers is also seen.   Control- fungicides.

35. 34.Pseudostem heart rot caused by Fusarium moniliforme , Gibberella fujikuroi Symptoms- Severe tip rot with pronounced brown to blackening of young rolled central leaves tissues. These may remain folded or become nearly fully unrolled as they emerge from the crown. This decay was sometimes present only in the upper portion of the pseudostem but it could be tending to take a downward direction in the core of the pseudostem Control- fungicides.

36. 35.Root & rhizome rot caused by Cylindrocarpon musae Symptoms- Rotting of fleshy roots and rhizomes  takes place.    The stem break. The disease affects the outer layers of the pseudostem . A strong odour is associated with the rotting. Control- fungicides.

37. 36.Sclerotinia fruit rot caused by Sclerotinia sclerotiorum Symptoms- water-soaked spots on fruits, stems, leaves, or petioles which usually have an irregular shape. These spots enlarge and a cottony mycelium covers the affected area. The fungus spreads and the plant becomes a soft, slimy, water-soaked mass. The cottony mycelium usually produces numerous sclerotia , black seed-like reproductive structures, a reliable diagnostic sign of Sclerotinia (these usually do not form until after host death ). Dry lesions appear on the stalk, stems, or branches.The lesions enlarge and girdle the plant part. Distal portions of the plant become yellow, then brown, then die. The girdled portion is often the base of the plant which causes the plant to die. Sclerotia form within the stem pith cavities, fruit cavities, or between tissues (i.e., bark and xylem).  Control- biological control  , fungicides, Crop rotation, Resistant  varieties, fungicides.

38. 37 .Sooty mold caused by Limacinula tenuis Symptoms-A black, powdery coating adhering to plants.   It merely blocks sunlight, and very rarely may stunt a plant's growth and yellow its foliage Control- wash affected plant parts with lukewarm water and soap, insecticidal soap or dish soap , using formulations of  neem oil .

39. 38 .Speckle caused by Mycosphaerella musae Symptoms- Leaf spots first visible as pale greenish flecks, ellipsoid to oblong, forming streaks pale to blackish brown, turning orange or dark brown, merging and forming large patches, occasionally somewhat target-like. Spread is by airborne spores.Light brown irregular blotches on the lower surface of the leaf, darkening to dark purple to black, and becoming visible on both leaf surfaces. May coalesce to give large bleached necrotic areas . Present only on leaves five and six and older before flowering. When infection is severe, there is a loss of leaves and bunches are small, and ripening is uneven. Control- Reduce plant density to lower leaf infection, Collect, remove and destroy heavily speckled leaves from plants, as well as tras , Remove shade and weeds, fungicides.  

40. 39 .Squirter (black end disease ) caused by Nigrospora sphaerica Symptoms- Spots initially appear brown, circular and irregularly distributed on the leaves and they eventually coalesce. Fruiting twig and shoot blight developed from the tips toward the base.  Control- plantation sanitation and fungicide.

41. 40.Tropical speckle and   Leaf speckle caused by Ramichloridium musae =  Veronaea musae =  Periconiella musae Symptoms- Diffuse irregular or circular, grey, brown or black blotches, especially on underside of older leaves . Similar symptoms also occur on leaf and fruit stalks. Leaves are covered with small, evenly spread aggregations of black spots that are individually the size of a pinhead. On the older leaves the dots may merge to form blotches". It also appear on young foliage as tan coloured circular blotches on the underside of the leaf . Similar symptoms are also found on leaf midribs and fruit stalks. Control-