50 M.W. ROOMI et al.: Studies on the Control of Subterranean Termites by Inorganic Pesticides direkt treffen. Alle kleinen Nagetiere -- als Wirte der Zecken -- verwenden die Wilhlmaus-Laufwege. Literature Cited MCENROE, W.D., 1979: Dermacentor variabilis (Say) in eastern Massachusetts. Rec. Adv. in Acarology 2, 145--153. McENRoE, W.D., 1986: Regulation of the American dog tick, Dermacentor variabilis (Say) (Acari, Ixodidae) two cohort population in the coastal area of Massachusetts. J. Appl. Ent. 102, 370--379. McENtio~, W.D., 1987: The relationship between the size of the spring adult cohort of Dermacentor variabilis Say (Acari, Ixodidae) and its parental breeding season under relaxed winter regulation. J. Appl. Ent. 104, 531--532. McENRoE, W.D.; SPECHT, H.B., 1987: Age effect analysis of Dermacentor variabilis adult populations during seasonal ac- tivity (Acari, Ixodidae). Can. J. Zool. 65, 455-457. SONENSmNE, D.E.; HmNES, G., 1985: A convenient method for controlling populations of the American dog tick, Der- macentor variabilis (Acari: Ixodidae), in the natural environ- ment. J. Med. Ent. 22, 577--583. Author's address: Prof. Dr. W.D. MCENROE, University of Massachusetts at Amherst, Suburban Exp. Station, 240 Beaver Street, Waltham, MA 02254, U. S. A. Ariz. Sch~idlingskde., Pflanzenschutz, Umwehschutz 63, 50--52 (1990) 9 1990, Verlag Paul Parey, Berlin und Hamburg ISSN 0340--7330 Pakistan Council of Scientific and Industrial Research Division of Applied Biology, KaraehL Pakistan Studies on the Control of Subterranean Termites by Inorganic Pesticides By M.W. ROOMI, A.H. SHAH, M. ANWARULLAH and M. HUSSAIN With one figure Abstract Studies on the wood preserving techniques against subterra- nean termites have been undertaken with a view to promote the use of inorganic indigenous pesticides in our country. The thin films of gelatine solution (glue of animal hides) containing 10 % calcium carbonate or 5 % copper sulphate as well as sodium silicate solution containing 12 % calcium carbonate + 10 % zinc oxide coated separately on wooden stakes prevented termite attack in soil up to 2, 4 and 5 years, respectively. Whereas control wooden stakes were found to be severely damaged by termites within 6 months. Stakes coated with Solignum| used as standard wood preservative for comparison remained free from termite infestation for a period of 5 years. 1 Introduction Termites or white-ants are the ancient pest of wood. Two thousand different kinds of termites species have been reported from the whole world.(FENEMORE, 1984). CHAUDHRY et al. (1972) reported 104 species of termites from Pakistan. According to the same author (1980), the most destructive and notorious species are Microtermes obesi, Heterotermes indicola, Coptotermes heirni and Odontotermes obesus. They are commonly found in our country and damage wooden fixtures in the buildings and the major agricultural crops such as cotton, wheat and sugar-cane. BORREX et al. (1960) have reported about the infestation of termites in buildings by the recognition of earthen tubes extending from the basements. In-organic wood preservatives like copper sulphate, lime and paris green have been used over many years for the control of termites and they are still in practice in the South asian countries, but they leach out in wet condi- tions within few months as reported by ROONWAL (1970). The present investigations deal with fixation of cal- cium carbonate and copper sulphate on wooden surface by using gelatine and sodium silicate solutions as adhes- ive against termite attack. 2 Methods Fir wood (Abies pindrow) was selected for grave-yard testing against termites. Forty eight stakes measuring 22 x 3 x 2 cm were numbered by metallic plates, weighed, and dried in oven at 85 ~ for 24 h. Each stake was weighed again for estimating the loss of moisture. Different formulations of inorganic pesticides were prepared in various solutions. After preliminary investiga- tions the formulations of calcium carbonate, zinc oxide and copper sulphate were selected for experimentation. The stakes were coated twice separately with 10 % calcium carbonate in gelatine solution, 5 % copper sulphate in gelatine solution, 12 % calcium carbonate mixed with 10 % zinc oxide in sodium silicate " solution, and Solignum| used as a standard wood preser- vative for comparison. Eight stakes were also coated with gelatine and sodium cilicate solution for control. Afterwards all treated stakes were placed for drying for 24h at 27~ The weight of each stake was noted again in order to find out the amount of pesticides used in each case. Grave-yard field tech- niques as described by ROONWAL (1979), COATON (1947), and GAY et al. (1955) were followed with slight modifications. Finally the treated and untreated control stakes were embedded in termite-infested areas near PCSIR Campus, Karachi. As the effect of pesticides depend upon weather conditions and the type of soil, another set of stakes were installed in termite mounds at Malir. The stakes were connected together by strips of the same wood at a depth of 18 cm below the soil level as shown in fig. 1. 50g of gelatine extracted from animal hides was soaked in 50 ml of water for 2 h. Afterwards 50 ml of water was slowly added. The soaked gelatine solution was dissolved in water by stirring at 60~ As gelatine solution gels a mass on cooling, 3.5 % phenol and 2.5 % zinc chloride were mixed in order to avoid this setback. Finally 5 g of copper sulphate was added to the above mixture. u.s. c,,m.,-i~htok..,,..,,,.,. C~.n,.,.c,,&. St.,,.,,,~.,,,: 0 3 4 0 - - 7 3 3 0 / 9 0 / 6 3 0 3 - - 0 0 5 0 5 0 2 . 5 0 / 0