Banana Major varieties
- Dessert types
- Cooking types
- Other varieties
Pest attacks and some diseases are commonly seen in these plants.
- Banana Bunchy Top Virus
- Banana Streak Virus
- Contingency Chlorosis
- Banana Bract Mosaic Virus
- Panama Disease
- Crown Rot
- Banana Pseudo stem Weevil
- Banana Rhizom Weevil
Banana Virus Diseases
1. Banana Bunchy Top Virus –BBTV
This viral disease is transmitted by Aphids. (Pentalonia nigronervosa) Infected plants show the following symptoms. Dark green lines along the leaf vein. Affected leaves are more upright. Leaves become pale yellow around the margin. The leaf margin is wavier and rolls upward. Shortened leaf petiole and stunts the growth. Immature and mature plants are affected. Use virus-free planting materials. Control banana aphids (vector). Cut and burn the infected plants.
2. Banana Streak Virus – BSV
Stunted and the fruit may be distorted. Have a thinner peel and occur in smaller bunches. Lines of yellow that run from the midrib of the leaf to the margin. These streaks are continuous or broken, and either scattered throughout the leaf or in bands. First, appear yellow streaks and as the leaf ages, the streaks turn brown. Embul variety is highly susceptible to this virus. Use virus-free planting materials. Control banana vectors. Cut and burn the infected plants.
3. Banana Bract Mosaic Virus
The virus is transmitted by Aphids. A mottled discoloration on the pseudostem.Discontinuous streaks on the bract of the banana inflorescence. Spindle-shaped streaks are irregularly scattered along the petiole. Removal of dead leaf sheaths.Red color patches on the stem.Diamond shape black spot on the bud. Use virus-free planting materials. Control banana aphids (vector). Cut and burn the infected plants.
Banana Fungal Diseases
1. Panama Disease
Also known as Fusarium wilt. Caused by Fusarium oxysporum. Embul variety is resistance to this disease. Alukehel and Kolikuttu are highly susceptible. First yellowing of outer leaves and plants die. Discoloration of the vascular system.
Sigatoka leaf spot disease involves two related ascomycetous fungi such as Mycosphaerella fijiensis and M.musicola.Mycosphaerella fijiensis causes black streak disease.M.musicola causes Yellow Sigatoka disease. Symptoms of these two are sometimes difficult to differentiate. Symptoms appearance on the upper leaf surface of pale yellow streaks or dark brown streaks on the lower leaf surface. In both diseases 1-2 mm long which enlarges to form necrotic lesions with yellow haloes and light grey centres. Lesions can coalesce and destroy large areas of leaf tissue results in reduced yields and premature ripening of fruit. Black streak disease is more serious than yellow streak disease because symptoms appear on younger leaves.
Banana Post-harvest Diseases
1. Crown Rot
Crown rot is the most serious and common post-harvest disease. Caused by Fusarium spp. A brown to black color develops on the “crown” where the hand was severed from the bunch. A layer of whitish mould later develops on the cut crown surface. The mould can penetrate deeply into the crown and the necks of the fingers, causing dry, black rot. Fingers may detach prematurely from severely infected crowns. The disease may increase rapidly during fruit ripening.
Caused by Colletotrichum musae. Symptoms occur as peel blemishes (black or brown), sunken spots of various sizes on fruits. The spots may have triangular-shaped or angular edges. The pathogen may cause symptoms on green fruit and may also enter the cut crown after hands are severed from stalks. Premature ripening of affected fruits may occur after infection. Avoid wounding fruit during harvesting. Field sanitation.Plat disease-free seeds. Use fungicide. (carbaryl)
1. Banana Pseudo stem Weevil (Odoiporus longicollis)
Female weevil punctures & lay eggs in the pseudostem. Grubs/larvae feed on the pseudostem tissue. Small pinhead size holes/ tunnels can be seen on the basal part of the pseudostem. Exudation of gummy substances from the holes.Yellowing of leaves. Stem become weakened and collapsed.
2. Banana Rhizome Weevil (Cosmopolites)
Attack to the rhizome and basal part of the pseudostem. Adult lay eggs and larva go to the rhizome. A feeding tunnel can be seen in a cross-section. Leaves turn into yellow. In severe infestation, the growth of the plant is retarded. Field sanitation- destroys pseudo stem parts of harvested parts. Use clean, pest-free planting material. Remove infected plants. Apply the recommended insecticides for planting holes. Use baits (slices of banana + recommended insecticides)