Termites of Desert Zones of Pakistan

Abstract

General composition of the termite fauna of desert zone was studied, using three sources for the collection of termites.

1. Collection of termites from trees along canal bank revealed the presence of three species, namely, Coptotermes hemi, Microtermes mycophagus, and Amitermes belli.Termites highly preferred Acacia arabica over Dalbergia sissoo (X2= 83.20; df = 1;P < .05).

2. Collection of termites from trees, soil cores and from sandy soil, revealed four species of termites namely, Coptotermes hemi, psammotermes rajasthanicus, Microtermes mycophagus and E.paradoxalis . The most abundant species of the area were Microtennes mycophagus and Eremotermes paradoxalis, the former being the typical desert species and the dominant element of the desert fauna.

3. Termite colonies recovered from agricultural fields revealed five species of termites, namely, M. obesi, M. mycophagus, 0. guptai , Eremotermes paradoxalis and E. neoparadoxalis.

WHEAT

4. Chak No.269/H.R Fortabbas. Three species of termites, namely, Microtermes mycophagus, Microtermes obesi, and Eremotermes paradoxalis were working in wheat fields at this locality. The

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frequency of occurrence of Mimycophagus in the soil cores was more than other species. Termite activity at this locality increased with the increase in atmospheric relative humidity, but the relationship was statistically nonsignificant (r = 0.53,df = 4; P > 0.05). Ch ak No.12 7/6. R. Faqirwali.

5. Termite species doing damage to wheat crop during 1991-92 were M. mycopliagus.tqcbesi and 0. guptai. Tu mite foraging activity during Feburary 1992 was 183. 87/m2 which gradually reached its maximum value (1004.24/m2) in May, 1992. At this locality termite population showed increasing trend with increase in atmospheric temperature (r = 0.96; df 5; P < 0.05). Increase in relative humidity due to late winter rains, suppre ssed termite foraging activity in the wheat fields (r =- 0.90; df 5, P < 0.05). During 1993, however ,

termite foraging activity in wheat field registered decrease with mcrease in atmsopheric and soil temperature.

CHAKN0.10.B.C.BAHAWALPUR.

6. During 1992, two species of termites, M. mycophagus and M. obesi were recorded from wheat fields, and the former was more abundant. Later on in 1993, further sampling recorded 0. guptai also. Maximum foraging population 1303.27/m2 was recorded in January 1993, when tLe crop was not yet supplied irrigation water, after sowing. Percent damage had cl relation with termite population/foraging activity and damage increased with increase in foraging popalution (r= 0.96; df = 2 P < 0.5).

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7. As regards vertical distribution of termites in wheat fields, termite activity was recorded in upper 15cm layer of soil.

Damage to wheat crop

8. During 1991-92, maximum damage to wheat crop at Chak No.269/H.R. and 127/6.R, Bahawalnagar was 1.06% and 4.39%, respectively.

9. During 1992-93?maximum damage to wheat crop at Chak 269/H.R.,127/6.R. and 10.B.C. Bahawalpur, was 2.63%, 10.95% and 8.84%, respectively.

10. The data of the three localtities was pooled to see the relationship of temperature, humidity and population density of foragers with the percent stands invaded by termites. There was positive and nonsignificant relationship between relative humidity and % stands invaded by termites (r = 0.37, df = 10, P > 0.05). On the other hand negative and nonsignificant relationship (r = -0.514 df 10, P> .05) was recorded between temperatureand percent stands invaded by termites. However, there was positive and significant relationship between termite population density/m2 and percent stands damaged by termites, indcating that damage depends on termites activity in the fields.

Loss in Yield:

11. For the first time in Pakistan, loss in wheat yield due to termite attack has been worked out and is being reported. At Chak No.127/6.R.Bahawalnagar, there was 2.54% loss in yield, loss in yield kg/acre was 104.23, and loss in terms of Rs/acre was 330.90.

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12. At chak No.126/6.R. Bahawalnagar, there was 0.63% loss in yield, loss in yield kg/acre was 38.95; and loss in terms of Rs/acre was 123.60. At 10.B.C Bahawalpur, there was 0.99% loss in yield and loss in yield kg/acre was 37.05, and in terms of Rs./acre was 117.34.

COTION

13. From cotton fields, five species of termites, namely M mycophagus, M. obesi, O. guptai, Odontotennes sp. and E. paradox/is were recorded in Bahawalpur division.

14. More stands were invaded by termites during hot months i.e, June, July and August.

15. Higher damage corresponded with higher population density/foraging activity of termites.

16. In the cotton fields higher ambient temperaturte increased the termite activity. Consequently more foraging activity 1272.98/m2 and 233.80/m2 was recorded during July and August, respectively. During later months there was decline in the foraging activity and at Chak No.127/ 6.R. Bahawalnagar; and negative but significant relationship between temperature and foragers was recorded (R = -.925; df = 4, P < .05). Greater foraging activity was recorded during early stages of gr.owth of cotton crop. Consequently, more damage was done to crop at initial stage of growth, and there was positive and significant relationship between percent damge and population density (r = 0.82; df 4; P < .05). Control measures, therefore, are required during early stages of the growth of cotton crop, Cumulative

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damage to cotton crop at Chak No.127/6.R.JChak No.134/6.R.Bahawalnagar and 10 B.c. Bahawalpur was quite high and was 12.68%, 14.69% and 23.42%, respectively.

SUGARCANE

17. Three species were recorded working in sugarcane fields. These in descending order of importance and abundance were E. paradoxalis, M. obesi and M. mycophagus. Contrary to other crops, E. paradoxalis, was doing more damage than M obesi and M. mycophagus.,during 1992.

18. Eremoteres paradoxalis was recorded from 15cm as well as from 30cm layer of soil, while M. obesi and M. mycophagus, were active in upper 15cm layer of soil.

19. Younger stages of plants were significantly more damaged (r = -82.06; df 6; P < .05), than older stages.

CONTROL

20. In Pakistan use of chlorinated insecticides, for the protection of agricultural crops and fruit trees, even against termites shold be banned.

21. For the control of termites working in wheat fields, a chlorinated insecticide (just for comparison), Heptachlor, and two Pyrethroids, Sumicidin @ of 250ml/acre, and 375/acre and arrivo @ 250ml/acre and 375ml/acre were tried. Although Heptachlor worked more effectively against termites, but being chlorinated has the disadvantage of Biomagnification and is carcenogenic. Consequently its use in

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agricultural shold be discouraged. Instead, Sumicidin which gave good results should be recommended for controlling termites in wheat fields.

COTTON

22. In cotton fields efficacy of Sumicidin, Karate and Heptachlor was compared. Karate applied @ 330ml/acre and 495 /acre proved very effective in controlling termite and termite damage in cotton fields. Sumicidin also worked well but was not as effective as Karate. Karate, however, should not be used in wheat fields or should be used at a much lower concentration. Otherwise, plants growth is effected.

FORAGING EXPERIMENT

23. As regards foraging activity and abundance of termites on toilet rolls exposed to termites in an experimental plot in the desert area, Microtermes mycophagus with 41.04% frequency of occurrence was more abundant than the other three species: M. obesi, E. paradoxalis, and E. neoparadoxalis.

24. The highest number of termites (73.25/roll) belonging to M. mycophagus were rcorded on November, 2, 1992 at 34C temperature and 60% relative humidity, just after the lapse of summer season. 25. Maximum number of termites (34.45/roll) belonging to E.

paradoxalis , the second most abundant species,was also recorded on November 2, 1992.

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26. Intergeneric and not intrageneric competition was noticed on rolls . Maximum mixed infestation during the year was noticed in November, when 15 rolls were harbouring M. mycophagus and E. paradoxalis

27. The amount of feeding done by termites on the toilet ro11s started increasing from June onwards, and maximum feeding was recorded in october, 1992, and seemed to be influenced by increase in atmospheric relative humdity.

28. The present experiment.set up at the desert zone.has clearly shown that some termites are indispensable part of the ecosystem and paly a very important role in recycling of the nutrients and in enhancing fertility of the soil. Based on the present finding a hypothesis is suggested that tropical forest rich in the diversty of plant species must have rich termite fauna. Conversely, forests poor in the diversity of plant species must have poor termite fauna. The textural analysis and particle size of the soil collected from galleries made by termites on the toilet rolls and the adjoining desert sandy soil has revealed number of interesting phenomena .Particale size analysis of galleries of termites on toilet rolls showed considerable enrichment in clay (22% clay; 22% silt and 56% sand), relative to the adjoining soil (1 % clay; 5% silt and 94% sand). There was increase in organic matter in termite constructed galleries (0.37) relative to the adjoining sandy soil (0.034). Similarly there was increase in C03, HC03 Cl, S04,Ca, Mg, K and Na contents, relative to the surrounding soil.