Types of pests and diseases on corn In the vegetative phase ( 0-14 days after planting )

Pests and diseases are constraints on the cultivation of maize . There are several types of pests and diseases is a major obstacle in the cultivation of corn that can reduce the quality and quantity of results . The main pests that attack corn seeds are flies , caterpillars soil , lundi ( uret ) , stem borers , armyworms , leafhoppers corn , cob borer . Beetle pests in storage is powdered and Tribolium castaneum . Corn crop diseases are downy mildew , Little Mosaic Virus , leaf spot , upih leaf , stem rot and ear rot . Many fungi that infect corn in storage is Aspergillus flavus , A. Parasiticis . Controlling pests and diseases that attack maize adapted to the growth phase .

1 . Flies seeds ( Atherigona sp . )
Small seed flies , egg -shaped elongated and placed on the youngest leaves ( hypocoty ) . After 48 hours the eggs hatch at night , out of the eggs and larvae move quickly toward a point which is the main food growing . This pest attacks the crop began to grow until the plant since about a month old . Fly larva gnawing seed plant shoots and go up into the shaft . Flies like plant seeds of youth between the ages of 6 to 9 days after planting (DAP ) to lay their eggs . At that time the new crop of leaves 2-3 strands and in general most fly eggs laid on the first leaf ( Soejitno et al . 1989) . At a certain depth the grubs usually gets moving again after broaching the plant stem , then out to become pupae in the ground ( Iqbal et al . 1988 ) . In severe attacks , corn crops can wither and die or do not die when growth is hampered ( Kalshoven 1981) . Flies breed quickly seedlings with the high humidity , therefore flies in the rainy season is a major pest of corn . Life cycle ranges from 15-25 days . A fly females capable of laying 20-25 seed grains ( Kalshoven 1981) . To control use of resistant varieties and seeds through the soil treatment at planting time or given the age of the plant leaf buds one week at a dose of 0:24 kg ai / ha .

2 . Black cutworm ( Agrotis ipsilon Hwfn . )
Agrotis ipsilon moths lay eggs one by one in a row or placed tightly on one surface of the leaves on the plant near the soil surface . Female moth can lay eggs ± 1800 grains . Stadia eggs 6-7 days . Young larvae are fototaksis , while older larvae are geotaksis so during daylight hours hiding in the ground and reappear to eat at night . One generation may take 4-6 weeks . Control : planting simultaneously , can also be done inundation .

3 . Lundi  ( Phyllophaga hellen )
Beetles or flies after the first rain is quite heavy , causing the soil moderately moist . Eggs are laid one by one on the ground . Egg stage 10 -11 days . Active larval stage larvae ± 5.5 months and about 40 days of inactivity . Section larvae attack the roots of corn plants , causing plants to wither and fall or die . Control : crop rotation or cultivate the land properly to turn off the larvae .

4 . Downy mildew ( Peronosclerospora sp . )
In Indonesia there are 2 types of fungi that can cause downy mildew is P. maydis and P. philippinensis ( Semangun 1973), however in 2003 has been found P. sorghi in Highlands Karo , North Sumatra ( Wakman and Hasanuddin 2003 ) . The symptoms of downy mildew , leaf berklorosis part or all of the leaves , when plants are infected early will cause stunted plants , no fruit . Control : seeds to be planted seeds treatment done in advance using the active ingredient metalaxyl , or Nordox 56WP fungicide sprayed on the plant began at the age of 5 days after planting until no longer gutasi in plants , and can also use resistant varieties such as local ordinance, Lagaligo , Surya , Bisi - 4 , Pioneer ( 4,5,9,10 and 12 ) .

5 . Dwarf mosaic virus disease ( VMK )
Cause of the disease is caused by Sugarcane Mosaic Virus , Cucumber Mosaic Virus or Pygmy Mosaic Virus . Visible symptoms on leaves with a change in the color of the light green among the dark green normal . Control : application of insecticides for vector control with the active ingredient monokrotofos , Tamaron or Thiodan and conduct eradication in infected plants .