http://bodelen.com/afu.php?zoneid=2208006 Agriculture and Technology Pests and Disease Management in Cotton - Agriculture and Technology

Information Related to Soil, Irrigation, Ideal Growing Conditions for different crops, Pest and Disease Management

Pests and Disease Management in Cotton


Disease

Symptoms

Cause

Comments

Management

Cutworms ( Black cutworm, Variegated cutworm )

(Agrotis ipsilon Peridroma saucia )

Stems of young seedlings may be severed at soil line, larvae causing damage will be active in night and hide during day, larvae will exhibit different pattern and curl into C-shape when disturbed

Insect

Insects outbreak favored by cool, wet spring followed by a mild winter, cutworms have a wide host range and attack vegetables including asparagus, bean, pea, potato etc.,

Remove all residue from soil after harvest or at least two weeks before planting, appropriate insecticide recommended, if not grown organically

Aphids ( Cotton Aphid )

(Aphis gossypii)

Soft body insects found under the leaves, green or yellow in color depending on the species and host plant, if aphid infestation is heavy it may cause leaves to yellow and stunned shoots

Insect

Honey dew excreted by aphids promotes the growth of mold

Insecticides are are recommended, if aphid infestation is high, plants generally tolerate medium level

Cotton bollworm

( Helicoverpa Zea)

Holes chewed in bases of bolls and insects frass around holes

Insects

Adult insect is a pale green to tan, medium sized moth

Monitor plants for eggs and young larvae, appropriate chemical treatment may be required for commercial plantations

Armyworm

( Spodoptera exigua )

Heavy feeding by young larvae leads to skeletonized leaves, dry wounds on fruits

Insects

Insects go through 3 – 5 generations a year

Organic methods of controlling armyworms include biological control by natural enemies which parasitize the larvae and the application of Bacillus thuringiensis

Fusarium Wilt

( Fusarium Oxysporum )

Wilting of cotyledons and seedling leaves, older plants exhibit symptoms of wilting and leaf chlorosis

Fungus

Disease favoured by warm temperature, fungus may spread due to infected seed or human movement

Use certified disease free seed, fumigating the soil may reduce disease incidence

Alternaria leaf spot

(Alternaria macrospora )

Small and circular brown lesions on cotyledons and seedling leaves which expand and develop a concentric pattern

Fungus

Nutrient deficiency, plant stressed by drought and other pests are more susceptible to the disease

Provide plants with adequate irrigation and nutrients, Potassium application may be required on susceptible cultivars

Cercospora leaf spot

( Cercospora gossypina )
Circular red lesion on leaves which enlarge and turn white or grey in the center

Fungus

Fungus overwinters in crop debris from previous growing season

Application of appropriate fungicide may be required on susceptible cultivars, adequate irrigation and nutrients recommended

Bacterial blight

( Xanthomonas campestris )

Water soaked spots on leaves which are delimited by leaf veins giving them an angular appearance, lesions increase in size and turn black and necrotic

Bacterium

Disease often introduced by infested seeds

Use of resistant cotton varieties is the most effective method of controlling the disease

Asochyta blight

( Asochyta gossypii)

Brown or grey spots on leaves surrounded by a red halo

Fungus

Disease favored by cool, wet weather

No fungicides are currently registered for use in cotton, plow crop debris into soil after harvest

See also :


Share on Google Plus

About Unknown

This is a short description in the author block about the author. You edit it by entering text in the "Biographical Info" field in the user admin panel.

0 comments:

Post a Comment

http://teslathemes.com/amember/aff/go/myblogg4u/?cr=aHR0cDovL2FncmljdWx0dXJhbGluZm9ybWF0aW9uNHUuYmxvZ3Nwb3QuaW4=