Pest characters, Nature of Damage and Control Measure of Sugarcane Top Shoot borer, Sugarcane Stem borer

Sugarcane Top Shoot borer. https://cststudy.blogspot.com

Sugarcane Top Shoot borer

Scientific name: Scirpophaga excerptalis. 

Family: Pyralidae. 

Order: Lepidoptera. 

Pest characters 

        i.            Adults are milky white in colour. 

      ii.            Insects found in India, Pakistan and Bangladesh. 

    iii.            Larvae are also white in colour. 

Nature of Damage 

1.  It is serious pest of sugarcane.  

2.  Adult female lays eggs on underside of the leaves in masses which is covered with brown tuft of hair.  

3. After hatching the eggs, the young larvae enter into the mid rib of leaf mining there towards the leaf base. From there the larvae enter into the growing point (Spindle) and feed inside.  

4.  Depending on the age of plant two types of symptoms are developed.   

5.  When plants are attacked at early stage before cane formation, the central leaf die. The symptom is called "Dead heart". 

6. When the plants are attacked at later stage (after cane formation) a bunch of leaves develops from the top of the plant and the symptom is called "Bunchy top".  

7.  If dead heart symptom appears then 100 % loss occur and if bunchy top symptoms occurs then 20 % loss may occur. 

Control Measure 

A. Non­chemical 

1.      Collection and destruction of adults and egg masses. 

2.      Infestation free setts should be used. 

3.      Destruction of infected plants. 

4.      Avoiding of ratooning crop. 

5.      Excess nitrogenous fertilizer should be avoided. 

6.      Trichogramma chilonis and Isotima javensis parasitoids should be released against 3rd or 4th broods. 

B. Chemical 

1.      Application of Diazinon/ Diginol 60 EC @ 3 ml/L of water. 

2.      Application of Curaterr 5G @ 40 kg/ha. 

3.      Application of Azodrin/ Nuvacron 40 WSC @ 3 ml/L of water.

Sugarcane Stem borer. https://cststudy.blogspot.com

Sugarcane Stem borer

Scientific name: Chilo tumidicostali. 

Family: Pyralidae.  

Order: Lepidoptera. 

Pest characters 

Adults are pale brown in colour with white hind wing. 

Nature of Damage 

1.  A female adult lays eggs in masses usually on the under surface of the leaves.  

2. Sometimes they lay egg on leaf sheath. After hatching egg, the larvae collectively bores into the stem and feed inside.  

3. Depending on the age of the plant, two times of symptoms are developed when plant attacked at  early stage (Just after cane formation) the affected plant may die and the symptom may called "dried top" symptom. 

4. But when the plants are attacked at later stage plant usually do not die but suffer from severe damage. 

5. The larvae feed inside making tunnel and secondarily fungal infection may be occurred. As a result the attacked tissues decomposed and the sugarcane become unfit for human consumption. 

Control Measure 

A. Non­chemical 

1.      Collection and destruction of egg masses and infected plants. 

2.      Planting of borer free setts. 

3.      Removing the dried tops. 

4.      Avoid ratoon crop. 

5.      Use light trap. 

B. Chemical 

1.      Sett treatment with coal and Agben 50 EC @ 1 ml/L of water. 

2.      Application with Diazinon/ Diginol 60 EC @ 3 ml/L of water. 

3.      Application of Sevin 85 SP @ 1.7 kg/ha. 4.  Application of Lebacid 50 EC @ 1 L/ha.