History of whitegrub project in Assam:

The center started functioning in August 2004 for research on agriculturally important soil arthropods of North-East hill region of India. Very little work on biology, bionomics, behaviour, seasonal incidence, population dynamics, crop losses and integrated management of whitegrubs and other soil arthropods have so far been carried out in this part of the country. Therefore, one of the major mandates is to explore and investigate the aforesaid aspects of whitegrubs and other soil arthropods. Except tea, most of the crops grown in this region are generally free from pesticidal umbrella. Therefore, a wide array of soil dwelling natural enemies of different crop pests and other useful soil micro arthropods is available in N,.E. India. There is a huge scope to investigate and search for new soil borne entomogenous fungi and their subsequent utilization in crop pest management. The research on the role of soil micro and meso fauna in the formation of humus, break down of organic m atter and nutrient cycling is still to get its momentum in this region.

Scientists associated with the Project:

SNo	Name of the Scientist	Photo	Designation	Contact	Date of Joining in the Project
1.	DR. A. A. L. H. BARUAH		Principal Scientist and PI, AINP on white grubs and other soil arthropods	Assam Agril. University, Jorhat Tele No.: 0376 -2310886(0) 0376 -2311156(R) 09435357016 (M) E-mail: adilbaruah@aau.ac.in , Adil_baruah@yahoo.co.in	01.10.05
2.	DR. BADAL BHATTACHARYYA		Junior Entomologist AINP of white grubs and other soil arthropods	Assam Agril. University, Jorhat Tele No.: 0376-2310886 (0) (M):09435648957 E-mail: badal23in@yahoo.com	05.11.04
3.	Mr. Utpal Bhuyan		SRF, AINP on White grubs & OSA	Assam Agril. University, Jorhat Tele No.: 0376-2310886 (0)
4.	Mr. Dwiban Pujari		SRF, AINP on White grubs & OSA	Assam Agril. University, Jorhat Tele No.: 0376-2310886 (0)

Important species of Soil Arthropods in Assam:

The important soil arthropods infesting various crops in Assam are as follows:

Whitegrub: Holotrichia sp, H. consanguinea Blanchard, H. longipennis Blanchard, H. sikkimensis Blanchard, Apogonia sp., A. aerea Blanchard, Adoretus sp, A. ferruginea Fabricius, A. aerial Arrow, Adoretus pallens Blanchard, Anomala sp., A. chlorosoma Arrow, A. chloropus Arrow, Anomala dorsalis Fabricius, Lepidiota mansueta Burm

Cut worm: Agrotis ipsilon Hufnagel

Termite: Odontotermes obesus (Ramb.) and Microtermes obesi (Holgren)

Red ant: Dorylus orientalis Westwood

Burrowing cricket: Brachytrupes portentosus Licht

Mole cricket: Grylotalpa africana P de B

[1]. WHITEGRUBS: The survey on scarab beetles fauna of Assam revealed a wide array of beetles including several new records. The scarabaeid fauna of Assam alone comprised of 20 species representing 10 genera and 4 subfamilies. Out of 20 species, 18 species have been identified for the first time from Assam. The major and economically important species of scarab beetles along with their relative abundance and hosts is presented here:

Scarab beetles recorded from Assam



[2]. CUT WORMS: Cut worm or greasy surface caterpillar viz, Agrotis ipsilon Hufnagel is an important polyphagous soil pest of cole crops like cauliflower, cabbage and knolkhol and other vegetable like potato, cucurbits, pea, okra etc. It also attacks rapeseed and mustard. Cut worm infestation in vegetables may go up to 35-40 per cent in potato; especially in TPS transplanted crop. The seedling mortality in potato crop may be as high as 25-30 per cent due to cut worm within 10-20 days of germination. The tuber infestation varies from 2.91 to 12.21 per cent. Of late, cut worms have become a major cause of seedling loss in vegetables grown in plastic green houses.





[3]. TERMITES: Termite is a perennial problem in many tea growing areas in the state. However, in field crops the attack of Odontotermes obesus (Ramb.) and Microtermes obesi (Holgren) are noticed in sugarcane, wheat and maize. Sugarcane setts (preserved and planted) as well as standing crops are very often attacked by the termites. Sett infestation may be up to 90 per cent while infestation in standing crop may vary from 10-20 per cent. Termite infestation in wheat and maize ranges from 5-10 per cent.



[4]. RED ANT (Dorylus orientalis Westwood): Red ant is a serious problem in all the potato growing areas of Assam. Tuber infestation in severe cases may be as high as 51.77-61.50 per cent. .Red ants have recently emerged as a sporadic pest of French bean in some places of Assam.



[5]. BURROWING CRICKET (Brachytrupes portentosus Licht): It attacks rabi and summer vegetables and wheat during the seedling stage. The extent of damage in vegetables may be up to 25 per cent.

[6]. MOLE CRICKET (Grylotalpa africana P de B): Mole cricket (G. africana) also attacks wheat crop and the seedlings of winter vegetables in Assam. It is also an occasional pest of potato responsible for 18.07-38.97 per cent tuber damage.

Major crops infested by Soil Arthropods in Assam:

The important soil arthropods infesting various crops in Assam are as follows:

1. Whitegrub: Green gram, Black gram, French bean, Rose, Potato, Sugarcane& Colocasia

2. Cut worm: cauliflower, cabbage and knolkhol and other vegetable like potato, cucurbits, pea, okra

3. Termite: sugarcane, wheat and maize. Sugarcane setts (preserved and planted) as well as standing crops

4. Red ant: French bean

5. Burrowing cricket: rabi and summer vegetables

6. Mole cricket: wheat crop and the seedlings of winter vegetables, Potato

Salient research achievements:

1. The survey conducted in different locations of Assam has revealed a wide array of scarab beetles including several new records from the Assam. The scarabaeid fauna of Assam alone comprised of 20 species representing 10 genera and 4 subfamilies. Out of 20 species, 18 species have been reported for the first time from Assam.

2. The most predominant species of whitegrubs are Anomala spp. Apogonia spp., Adoretus spp., Holotrichia consanguinea and Lepidiota mansueta and these were collected from diversed crop habitats.

3. During the last couple of years, Lepidiota mansueta has drawn special attention because of its severity and distribution. The grubs of this species were found to cause severe damage to crops like potato, sugarcane and colocasia at Majuli, Jorhat.

4. Investigation on the relative abundance revealed that Anomala spp. was the most dominant species contributing 38.24 per cent out of the total number of scarab beetles trapped during 2006-07 followed by Apogonia spp. (26.46%) and Adoretous spp. (18.52%). The Holotrichia spp. comprised of 11.16 per cent, where as, the population of Coprus sp. was found to be very negligible (1.10 %).

5. Nine species of insectivorous birds with encouraging predatory activities have been identified from Assam.

6. From the field collected larvae of cutworm and whitegrubs, the natural infection of inhomogeneous fungi, Metarhizium anisopliae was observed.

7. Fourteen species of ants have so far been identified from the Jorhat district of Assam from different habitats.

8. Eight species of ants have been collected and identified from sundew (Drosera) plant (an insectivorous plant) from the foothills of Barak Valley of Assam.

9. The detail study on seasonal incidence and population estimation of cutworm, Agrotis ipsilon in potato crop raised from True Potato Seeds (TPS) has been carried out.

10. While studying the soil microarthropods of Assam, it was found that the population of collembolans and soil mites was considerably higher in Forest ecosystem as compared to Agro ecosystem and Fallow land.

Important recommendations:

The following technology has been recommended and included in the Package of Practices of Rabi Crops of Assam:

"Three budded sugarcane setts may be dipped in solution of chlorpyriphos 20EC @ 2ml/lit for 30 minutes before preserving the setts in "deep trench trash cover" method".

Ongoing Research Projects:

[1]. Multilocation Trials:

Expt. No.1: Monitoring Of Soil Arthropods

A. Species profiling of soil arthropods through light trap:

B. Monitoring of natural enemies of soil arthropods:

C. Scouting:

Expt. No.2: Management of Whitegrubs Through Chemicals

A. Field evaluation of insecticides as soil application

B. Field evaluation of Insecticides as post-sown soil application in standing crop: (20-22 days after mass beetle emerged)

Expt. No.3: Microbial Control of White Grubs

A. Field evaluation of entomopathogenic fungi, Beauveria brongniartii and Metarhizium anisopliae and against white grub

Expt. No.4: Management of cutworm

Expt. No.5: Preparation of inventory of soil Arthropods (GroupWise classification) under different Agro Ecosystem by Tullgren Funnel Method (TFM).

[2]. Location Specific Trial:

Expt. No.6: Management of termites in preserved setts of sugarcane

Under the aegis of this project, training programmes on various aspects of soil insect pests and their management have been conducted through various agencies including KVKs of Assam