Insect attack and management of maize crop in Bangladesh

Image Source

Maize is an important cash crop of Bangladesh which can be cultivated all the year round. Maize is more nutritious than rice and wheat. It contains about 11% of non-vegetarian ingredients. Due to improved nutrition and multiple uses, maize cultivation in Bangladesh is increasing day by day. Corn kernels are used as human food, tree and green leaves as cattle feed and poultry and fish as food. In 2016-17, the area under maize in Bangladesh was 369,600 hectares and the production was 3,026,000 metric tons. The average yield of maize is not as expected. One of the main reasons for low yields is the attack of various types of harmful insects. These pests affect maize production and their attack destroys a significant portion of the crop. In addition, due to climate change and other reasons, new insect attacks are being seen in maize crops in Bangladesh. In this situation, it is very important to gain knowledge about the type and management of pests to protect the crop from pests. The following is a discussion on the major pest infestation and management of maize crops.
Insect bites
Insect larvae cut the roots of seedlings adjacent to the soil. A larva can cut the roots of more than one tree. The larvae hide in cracks, rocks and debris during the day and cause damage at night. Excessive attack reduces the number of trees in the land and reduces the yield. Adult larvae are 40-50 mm long, dark brown or matte in color.
Management

• Insect larvae and pupae should be collected and killed during land cultivation.
• The larvae hide near the cut seedlings. For this, the larvae have to be killed by digging the surrounding soil by hand in the morning.
• When the field is irrigated, the larvae come out. At this time you have to arrange for the birds to sit on the stick.
• The following pesticides should be applied in severe attacks-
  Chlorpyrifos (Darsban 20 EC or Pyrifos 20 EC or Classic 20 EC or other names) 5 ml per liter of water or Nitro 55 EC 2 ml per liter of water or 20 kg carbofuran (Furadan 5G, Briefer 5G or other names) should be applied per hectare at the time of sowing. .
  Jab insects
  Both adult insects and nymphs suck sap from the leaves, new tips, tassels, and green shoots of young shoots. They produce shoot mold in the affected part as a result of honey juice secretion and turn black. When honey juice is produced in the tassel, pollination is disrupted and the mocha does not form grains properly. Excessive infestation disrupts plant growth and may reduce yields. They act as carriers of viral diseases.
  Management
• Adult insects and nymphs are grouped on tips and leaves in the early stages. In this case they have to be crushed by hand.
• Different friendly insects such as Lady Beetle, Sirfidfly and Jaffa are eaten by newbies. All these friends have to make arrangements to save the insects.
• In case of excessive infestation, 1 ml of Malathion (Phifanon 57 EC, Siphanon 57 EC, Malaton 57 EC, Malataf 57 EC, Sumadi 56 EC or other names) should be applied in 1 liter of water.
  Mazra insects
  The larvae penetrate the young stems and cut the base of the dig leaves. As a result, the faded tip of the tree (Uvdhaf Javadhat) symptoms appear. The affected tip dries out and rises when pulled. They attack large trees, pierce the trunk and eat the inside. As a result, large trees break down in low winds, they attack the tassels in the middle leaf hole, cut the tassels (Figure-1) and disrupt the pollination. After catching the mocha, they attack the mocha and destroy the grain. They are effective at night. The mature larvae are 20-25 mm long, with many stripes on the skin with colored stripes. These maize as full-grown larvae are located on post-harvest trees, stalks, and uncollected grains and re-attack the following season.
  Management
• Residues should be destroyed after harvesting because insect larvae are present in them.
• Collect and destroy piles of eggs.
• Carbofuran (Furadan 5g, Briefer 5g or other names) should be applied per hectare at the time of sowing in severely affected areas.
• Larvae should be collected from the affected trees and destroyed.
• Apply 20 kg carbofuran (Furadan 5g, Briffer 5g or other names) per hectare from the top of the maize plant in such a way that the pesticide grains get stuck inside the leaves.
• In case of excessive attack, Diazinon (Sebion 60 EC, Haginon 60 EC, Diazol 60 EC, Diazon 80 EC, Diazinon 60 EC or any other name) or Carbosulfan (Marshall 20 EC, Sunsulfan 20 EC) should be applied in 20 ml, General 20 EC -
  Pink beetles
  The newborn larvae pierce the young stems and eat the inner soft part, resulting in death of the middle tip or mite. The larvae are pinkish in color with dark orange heads. The affected tip comes up when pulled with the hand. They attack the tassel by piercing the middle leaf, cutting the tassel, which prevents pollination.
  Management
• Light traps must be used.
• Larvae should be collected and destroyed from infected plants.
  Carbofuran (Furadan 5g, Briffer 5g or other names) should be applied at the time of sowing in heavily infested areas.
  Additional attacks should be Diazinon (Sebion 60 EC, Haginon 60 EC, Diazol 60 EC, Diazon 60 EC, Diazinon 60 EC or other names) or Carbosulfan (Marshall 20 EC, Sunsulfan 20 EC, General 20 EC or other names) .
  Armyworm
  Insect larvae attack and eat the soft inner leaves of the plant. They start eating along the edges of the leaves. Later the larvae attack the adult leaves. Excessive attack can make the tree leafless. Insect feces can be seen on infected trees. The larvae also attack the tassels and mocha of the tree. The pupa completes the step by forming a chamber inside the mature larvae.
  Management
• The larvae should be collected by hand from the affected trees and destroyed.
• Insect pupae present in the soil should be collected and destroyed during land cultivation.
  In severe attacks, Spenosad (Tracer 45 sc 6, 0.4 ml / liter or Success 2.5 sc @ 1.3 ml / liter) or Emamectin benzoate (Proclame 5 SG, Saham 5 SG, Haklem 5 SG or other names): 1 g / liter ) Pesticides can be applied-
  Fruit armworm
  It is a new destructive pest of corn crop. In 2016, the first insect attack was observed in Bangladesh. It is an omnivorous insect, attacking 60 crops in 28 families, with maize being the most affected crop.
  They attack maize plants at all stages (seedling, organ growth, tassel and mocha granulation stage). Newborn larvae make small holes in the leaves and eat only the upper green part of the leaves. Later they eat the leaves extensively. As a result, large holes can be seen in the leaves. The larvae do more damage at night. With the extra attack, almost all the trees in the field were uprooted. The larvae live inside tree trunks to protect themselves from pesticides and natural enemies. They leave feces on the tree, which later dries out and looks like sawdust. They attack the tassel by piercing the middle leaf, cutting the tassel, which prevents pollination. After mocha, they penetrate the junction of mocha and stem and enter the mocha and eat the soft grains inside.
  Management
• Insect pupae present in the soil should be collected and destroyed during land cultivation.
• The pile of eggs and the newly hatched larvae (which are located on the leaves together) should be destroyed by hand.
• Before sowing, seeds should be purified and planted in the field (4 gm / kg seed).
• Collect larvae from infected trees and kill them.
• Sex pheromone traps are very effective for catching adult male insects. Immediately after planting the maize seeds, sex pheromone traps should be placed at a distance of 20-25 m in the affected area.