I /Ii,,!. Coli/mi. 15(2): 127-131, 2001

Field evaluation of Cotesiaflavipes Cameron (Hymenoptera: Braconidae) (Indonesian strain) against stalk and internode borers

R. K. TANWAR and ASHOK VARMA Division of Entomology, Indian Institute of Sugarcane Research Lucknow 226 002, Uttar Pradesh, India E-mail: [email protected]

ABS TRA CT: Field trials were conducted on the releases of Cotesia Jlavipes Cameron (Indonesian strain) against sugarcane stalk ( auricilius Dudg.) and internode (Chilo sacchariphagus indiclls Kapur) borers at IISR Farm, Lucknow for consecutive three crop sea­ sons 1996-97 to 1998-99. The parasitoids were released in one block @ 2000 mated females! ha I month split into four doses from July to October and the other block was treated as check. The results indicated reduction of 56.2, 69.6 and 43.1 per cent in stalk borer infestation in parasitoid released blocks as compared to check, in October during 1996- 97, 1997-98 and 1998~99, respectively. The results remained inconclusive in cases of internode borer due to low infestation.

KEY WORDS: Chilo auriciliu.f, Clli/o sacchllriplwgu.f indiclIs. Cotesia Jlavipes. parasitoid. field releases

Cotesia Jlavipes Cameron (Hymenoptera: 1979) and Thailand (Suasa-ard and Charernson, Braconidae). an important gregarious larval 1999). In the recent past the Indonesian strain endoparasitoid of different sugarcane borers, has been imported to India through Project namely Snellen, Chilo Directorate of Biological Control, Bangalore for sacchariphagus indicus Kapur, Chilo evaluation against sugarcane borers. Laboratory tumidicostalis Hmpsn., evaluation of this strain has already been done (Walker) and Acigona steniellus (Hmpsn.) is (Tanwar and Varma, 1996). In the present study widely distributed in different cane growing field evaluation of C. jlavipes (Indonesian strain) regions in India (Gupta, 1954; Kalra and was carried out at Indian Institute of Sugarcane Srivastava, 1966; Borah and Arya, 1995). Research farm against C. auricilius and C. s. Indigenous C.Jlavipes has been found effective in indicus. reducing the infestation of A. steniellus (Bindra and Chand. 1973), C. inJuscatellus and C. MATERIALS AND METHODS Clltricilius (Shenhmar and Brar, 1996) under Punjab conditions in India. This parasitoid has Nucleus culture of C. jlavipes (Indonesian also been successfully introduced against Diatraea strain) was received through the Project sacci1amlis (F.) in Barbados (Alam et ai., 1971), Directorate of Biological Control, Bangalore. Brazil (Macedo et al., 1984), Texas (Fuchs et al., Freshly emerged wasps were released into TANWAR and VARMA

transparent plastic jars (1.5Iit) fitted with brass mesh 5.1 per cent in both released and check blocks on the lid for ventilation and provided with cotton (Table I). The observation recorded in October swab soaked in 50 per cent sucrose solution as indicated lower infestation of stalk borer in the adult food. Rearing of the parasitoid was carried parasitoid released blocks as compared to check. out on laboratory bred larvae of stalk borer (Tan war The differences were statistically significant in and Vanna, 1996). 1997-98 and 1998-99. Under the Punjab conditions, the field releases of indigenous C. Block trials were conducted on the releases Jlavipes @ 800 adults/ha had been found effective of laboratory reared C. Jlavipes @ 2000 mated against C. infuscatellus. C. auricilius aJ/d A. females fha/month split into four doses (500 each) stelliellus. However, the Indonesian strain was from July to November for three consecutive years ineffective against borer complex (Shenhmar and (1996-97 to 1998-99) against sugarcane stalk and Brar, 1996). internode borers. The releases of the parasitoids were made in one block of 54x60m size with CoLk While observing the effectiveness of the 8102 planted in 1996-97 and 54x 180m with CoS released parasitoid on progressive stalk borer 91269 ratooned and CoLk 8102 ratooned in infestation (Table I, Fig 1) it was found that in 1997-98 and 1998-99, respectively. Another block October the released block indicated a reduction of the same size with same cultivars and agronomic of 56.2, 69.6 and 43.1 per cent in stalk borer practices was maintained in each year as a check infestation as compared to check during 1996-97. (unreleased) at a distance of 200m. The 1997-98 and 1998-99, respectively. However, in observations on the progressive field infestation January per cent reduction in the infestation of were recorded from 10 spots in each block (released stalk borer in released block was lower than and check) hy counting 50 canes including healthy October (52.9 and 28.9 in 1996-97 and 1997-98. and infested canes from each spot in July (pre­ respectively). No reduction in stalk borer release), October and January (at harvest). The infestation was noticed in 1998-99. It is due to observations at harvest were made by splitting the fact that from July to October the released canes to record infestation, larval population and parasitoid remained more active in the field for parasitisation of C. auricilius larvae. The results its parasitisation and multiplication which resulted were suhjected to 't' test for drawing the in a reduction in the infestation of stalk borer in conclusion. parasitoid released block. Beyond October, the RESULTS AND DISCUSSION prevailing low temperature, appeared to be non­ conducive for its mating (Al-Maliky and AI-Izzi, The i.nfestation of stalk borer in July, in 1990) and field parasitisation. general, remained low ranging from traces to

Table I. Effect of field releases of C. jlavipes (Indonesian strain) on the infestation of stalk borer

Period Cane bases per cent infestation of stalk borer (Mean + SEM) of 1996-97 1997-98 1998-99 observation Released Check Released Check Released Check

July Traces Traces 2.0 3.0 5.09+5.49 3.76+1.74

October 3.38± 1.38 7.7±1.38 8.56+1.72 28.15+2.89* 12.78+ 10.9 22.45+3.46*

January 17.47±4.93 37.15±4.25* 25.5+3.37 35.9+4.28 35.9+21.8 25.8+6.89 ( * Slgmficant, at P-0.05)

128' Field c'\alualioll of C ,"n·j!'i's Ilmionesian strain), again'l sugarc·an..: stalk and internode horers

Fig.1.Effect of field releases of C. flavipes on stalk borer infestation

35 D Released 30 0 Check 25 -e.....~ c 0 20 ;; .f1 fI) 15 oS! c 10

5

0 1 2 3 July Oct. Jan.

Obsenalions recorded during har\'est Oil I 997-9R and 1998-99 the larval population in gencral lal"val population and pal"a.,itizatioll III slalk horer rClllaincd lu\\. therefore. no reduction in larval indicated low population and higher parasitization population could he observed. The parasitization of stalk oorer larvae in 1996-97 in parasitoid was also very low (0 to 2.19 o/r) during 1997-98 and released hlock as comparcd to check. However, the 1998-99 in parasitoid released as well as check blocks diffcl-encc was non-significant (P= O.OS). During (Table 2).

Table 2. Effect of field releases of C. flavipes population and parasitization of stalk borer larvae

Parameters Cropping season

1996-97 1997-98 1998-99 Released Check Released Check Released Check Stalk borer larvae ± SEM II OOcanc 8.5S±2.30 27.3±8.08 9.98±1.89 lO.59±2.29 9.81±3.19 S.7I± 1.79

Paras i ti sati on (%) S.O ± 4.99 3.SS±2.28 2.19±I.S! NP NP NP

(NP - no parasitization)

129 TANWAR ami VARMA

Table 3. Effect of field releases of C. jlavipes on the infestation of internode borer

Cane bases per cent infestation of internode borer (Mean± SEM) Period of 1996-97 1997-98 1998-99 observation Released Check Released Check Released Check

July 0.83± 0.5\ 0.38± 0.38 2.0 2.0 0.8± lAO

October 0.72± 0.44 0.70± 0042 0.39± 0.83 0.98± 1.67 1.53± l.51 1.32± 1.52

January 7A3± 2042 4.86± 2.08 4.] 8± 3.25 2.27± 1.76 5.81± 3.34 4.20± 1.73

It is evident from the above observations AI-Maliky, S. K. and AI-Izzi. M. A. Z. 1990. The that the field releases of laboratory reared C. progeny production of a hymenopterous parasitoid, j7m'ipes @ 2000 mated females/hal month split Apallteles sp. group ultar, as affected by into f

Alam, M. M., Bennet!. F. and Carl, K. P. 1971. Biological Gupta, B. D. 1954. A note on the scope of biological control of Diatmea saccharalis (F) in Barbados control of sugarcane pests. Proceedings oJSecond by Apul//a/esjlal'ipes Cam. and Lixophaga dialaeae Biennial Conference oj Sugarcane Research and T. ElllOlllophaga, 16: ) 51·158. Development Workers. Illdia, 2: 229-235.

130 FidJ t:\'aluatinn of C thn'il'es (lndont:sian strain), against sugarcane stalk and internode horers

Kalra, A. N. and Srivastava. R. C. 1966. Biology of strains of Cotesiaflavipes (Cameron) on the control A{J{/lIleles flavipes Cam. (Braconidae: of sugarcane borer. Indian Sugar. 45: 877-879. Hymenoptera) a parasite of borers of sugarcane, under micro-ecological conditions, Proceeding V All India Conference of Suger calle Suasa-ard, W. and Charernson, K. 1999. Success of Research H·'t-Jrkers, Coimbatore (Madras), pp. 605- Cotesia j1avipes (Cameron) for biological control 609. of sugarcane moth borers in Thailand. Proceedillg XXIII ISCT Congress, 22-26 February, 1999, New Macedo, N., Mendonca Filho, A. E. Moreno. J. A. and Delhi, pp. 559-568. Pinazza, A. H. 1984. Evaluation of economic ad vantages of 10 years of biological control of D fat rac{I s pp. t hroug h Apalltefes Jfavipes Tanwar, R. K. and Varma. A. 1996. Rearing. biology Cameron, in the state of Alagoas (Brazil). and storage of Indonesian strain of Colesia j1avipcs Entomological Newslcltel; 16: 9-10. (Cameron) using sugarcane stalk borer Chilo auricilills Dudgeon as a host. JournaloflJiofo/!,icai Shenhmar, M. and Brar, K. S. 1996. Efficacy of two COll/rol, 10: 61-66,

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