First National Report Of Pakistan to the Convention on Biological Diversity Ministry of Environment Government of Pakistan Contents



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Chapter 6: Insect Biodiversity



Insect Species in Pakistan


By far the majority of invertebrates in the terrestrial environment are insects. A review of the available literature shows that the subject of insect taxonomy has yet to receive its due attention; this is reflected by contradicting figures on the number of species found in Pakistan. Souhail, 2007 quotes more than 500022 species, in other references the figure is 2000. A few species or groups of insects may occur in extremely large numbers and the biomass of invertebrates in a forest or plateau may be greater than the vertebrate biomass in the same environment. Pakistan has representatives of 13 insect orders. The orders of Protura, Thysanura and Diplura comprise a small numbers of species that live in the soil or in kitchens or food stores. More than 150 of such species are known to exist in Pakistan.

Grasshoppers and crickets (Orthoptera) form an order having 152 species recorded from Pakistan. Most members of the grasshopper family, Acrididae, live on vegetable matter, but some of the bush cricket families, Tettigoniidae, also eat other insects. Some are large beautiful insects, which can also attract attention via their song.

Earwigs (Dermoptera) form an insect order with many species in Pakistan. These live on the ground where they eat small insects and vegetation. They are most commonly found in dirty kitchens, sewage pipes, food stores, etc. Dust lice or book lice (Psocoptera) comprise an order of insignificant insects in Pakistan. There are two recorded species from Pakistan. They live beneath the bark of trees and feed on pollen and fungus myceli. A few species live in buildings and cause damage to books and Natural History collections.

Thrips (Thysanoptera) are very small slender insects with two pairs of thread-shaped wings with broad fringes. These live on plants, especially the flowers, ten species of which have been recorded in the country. There are more than 159 species of bugs (Hemiptera) recorded in Pakistan. Two species of Lacewings and alderflies (Nemoptera) are also recorded.

Other insect species recorded in Pakistan include:


  • Many species of scorpion flies (Mecoptera)

  • 25 species of fleas (Siphonaptera)

  • 400 species of butterfly (Lepidoptera) and

  • 50 species of Termites

Entomology is taught as a major subject in three agricultural universities: the University of Agriculture, Faisalabad; Sindh Agricultural University, Tando Jam, the University of Agriculture, Peshawar. Entomology’s major application is in the plant protection and community health sectors. Although this subject is of major economic importance for enhancing agricultural productivity, it has not been given the importance it deserves. There are a number of agricultural research stations in Pakistan, but entomologists have inadequate opportunities for advanced research and development in their field. Therefore, the present level of information on insect Biodiversity in Pakistan is very low. Integrated Pest Management (IPM) technologies that ensure reduction in the use of insecticides are applied on a very limited scale.

Use of Pesticides and Threats to Biodiversity23


Since the early 1950s, with the discovery of the insecticide properties of DDT, insecticides have been used excessively for pest control. During this period, due to the spectacular success of chemical control, other control techniques were almost completely ignored. The indiscriminate use of insecticides has adversely affected Biodiversity by killing or eliminating animal species. However, the development of resistance in pests against insecticides, the resurgence of secondary pests; pollution of the environment; and presence of pesticide residues in the food chain have stimulated renewed interest in alternative methods of pest control. Consequently, the interest in Integrated Pest Management (IPM) has developed. More than two hundred pesticides including insecticides, acaricides, weedicides, nematicides, rodenticides, etc. are registered in Pakistan. These are creating resistance in insect pests, causing serious environmental problems and posing a serious threat to Biodiversity.

At present, pesticides worth more than Rs.13 billion are imported into Pakistan annually. Most of these pesticides are non-selective toxic chemicals. Ecological and agricultural sustainability has become an essential consideration in Pakistan’s agriculture. The indiscriminate use of pesticides has been responsible for a number of problems such as environmental pollution, resistance in pests, and the upsurge of secondary pests due to the elimination of natural enemies.


IPM Projects in Pakistan


In Pakistan, foreign donor agencies including the World Bank, the Asian Development Bank (ADB), the Food and Agriculture Organisation (FAO) of the United Nations and the Swiss Development Co-operation mostly sponsor Integrated Pest Management (IPM) projects. NARC and CABI Bioscience as well as some other firms are implementing many IPM projects in Pakistan. The major on-going projects are:

  • Integrated pest management (IPM) of sugar pests in Sindh

  • Integrated pest management of cotton pests in south Punjab

  • Integrated pest management of cotton pests with emphasis on the white fly in Multan Civil Division, Punjab

The Government of Pakistan has made a lot of efforts for the introduction, research and implementation of IPM projects. Since 2004, Pakistan has committed US$7.7 million in public funds to integrate IPM into public policy, university curricula, provincial extension services and research and development. Projects at both national and provincial level are well on their way to using Farmer Field Schools to train 167 000 farmers in IPM over five years.

In Farmer Field Schools, farmers and facilitators spend one morning in a week during the cropping season in a typical field, observing insect behaviour and plant growth rates. Farmers see that beneficial insects often devour pests, and when this is happening, pesticide is not needed. Farmers, even illiterate ones, gain confidence and begin relying on their own judgement, even in the face of intense pressure from government agents and pesticide sellers to spray frequently and without reference to field ecology. According to Dr Iftikar Ahmad, Head of the National IPM Programme, farmers now are using less pesticide: "Our national data show a dramatic decline in pesticide use in Pakistan. Farmers are making more profit and a government study shows a 10 percent increase in cotton production thanks to IPM." Additional benefits included lower exposure to highly hazardous insecticides, especially for the women who pick most of the cotton by hand. The FAO-EU project supported local women physicians to monitor blood samples from women picking cotton; without IPM, their blood enzyme levels were dangerously reduced for more than a month after field work. With IPM, this did not occur.

The Biodiversity of agro-ecosystems is lower in comparison to less disturbed ecosystems. The use of insecticides further adversely affects Biodiversity by reducing the number and populations of insects, especially those of natural enemies. When pesticides are used indiscriminately natural enemies are the first to be eliminated, resulting in an upsurge of secondary pests disturbing the Biodiversity of the agro-ecosystem.

Of the various methods of pest control, Integrated Pest Management is the best for the conservation of Biodiversity. IPM programmes for a number of crops such as sugarcane, mango, apple and cotton have been developed in Pakistan. The biological control components of IPM are introduction, conservation, redistribution and augmentation.

In introduction and redistribution, useful and beneficial species are transferred from one area to another. If they become established, they permanently add to the Biodiversity of the agro-ecosystem. They do not eliminate the pest species but bring their populations to sub-economic levels thus enriching the Biodiversity of the ecosystem. Table 6.1 gives an account of successes achieved in Pakistan by elimination or minimisation of pesticide use and thereby directly contributing to Biodiversity conservation. A number of species have been successfully introduced and redistributed in Pakistan are indicated in Table 6.2 and Table 6.3.

In augmentation, populations of natural enemies are increased by their release at proper time. This is based on detailed studies on the biology and ecology of the pests and their natural enemies. The addition of useful species at a certain time of the season not only enhances Biodiversity but also provides cheap and safe control of the pests for which otherwise poisonous insecticides would have been used.

In Pakistan, very little effort has been made to study the Biodiversity of agro-ecosystems. The challenge is to conserve or improve it before it is destroyed. Studies on this important aspect of agro-ecosystems should receive priority.

Table 6.1: Successes in Biological Control and Integrated Pest Management in Pakistan


Crop

Pest

Control Measures

Remarks

Sugarcane

Pyrilla



Conservation of egg parasitoids



Complete control throughout NWFP, aerial spray was stopped and more than RS. 30 million are being saved every year since 1985.

Complete control in areas at Faran Sugar Mills, Tandlianwala Sugar Mills, Jamal Din Wali Sugar Mills, Habib Sugar Mills etc.






Borers


Introduction of Cotesia flavipese
Augmentative releases of Trichogramma

Excellent control achieved at Habib Sugar Mills, Faran Sugar Mills, Jamal Din Wali Sugar Mills, Tandlianawala Sugar Mills, Consolidated Sugar Mills. In addition, Bannu Sugar Mills etc.

Mass releases of eggs of the parasitoids

Telenomusdignus

Excellent control achieved at Habib Sugar Mills, Faran Sugar

Mills, Jamal Din Wali Sugar Mills, Tandlianawala Sugar Mills,

Consolidated Sugar Mills and Bannu Sugar

Mills etc.



Mango

Fruit flies and scale insects

Use of pheromone traps, release of

Coccinellid beetles

Excellent control of fruit flies and scale

insects


Mealy bug

By hoeing and ploughing

Good control of mealy bug was achieved.

Apple

Pest Complex

Biological control based IPM

Complete control of woolly aphid, San Jose scale, codling

moth and red spider mites. Number of pesticide sprays

considerably reduced.


Cotton

Bollworms

Mass releases of Trichogramma.

Excellent control of Bollworms

Sucking pests

Conservation of predators

Excellent control of sucking pests

In conservation, desirable species (natural enemies) are protected or encouraged by the judicious use of insecticides and cultural practices or by providing them shelter. Therefore, the populations of natural enemies are saved from destruction or elimination. This helps in improving Biodiversity. The natural enemies of the pests of mango, sugarcane and cotton have been conserved for pest control in IPM technologies.

Table 6.2: Natural Enemies Introduced from Other Countries

Crop

parasitoids

Country of origin

Year

Target pest

Where established

Reference

Maize and Sorghum

Cotesia flavipes


Japan


1962

Chilo partellus

Throughout Pakistan

Mohyuddin (1981)

Apple

Aphelinus mali


Switzerland

1989
1991- 92

Eriosoma lanigerum
E. lanigerum


Murree,

Azad Kashmir,

Malakand Division


Qureshi et al.,
Mohyuddin and Qureshi (1992)




Encarsia perniciosi


USA

1959-60


Quadraspidiotus perniciosus

Murree, Azad Kashmir,


Rehman et al., (1961)


Grape

Vines


Leptomastix dactylopii


Texas (USA) and Trinidad

1984-86

Planococcus citri


Quetta valley

-


Table 6.3: Successful Redistribution of Natural Pest Enemies in Pakistan

Natural enemy

Origin

Year

Target Pest

Where Redistributed

Reference

I

SUGARCANE

Epiricania melanoleuca

Punjab

1975

Pyrilla perpusilla

NWFP (Peshawar)







II

APPLE

Chilocorus infernalis

Murree

1990

Quadraspidiotus perniciosus

Kalam

Mohyuddin and Qureshi (1992)




Aphelinus mali

Murree

1991

Eriosoma lanigerum

Swat

Qureshi, et al., (in press)




Encarsia perniciosi

Murree

1993

Q. perniciosus

Swat

Mohyuddin and Qureshi (1992-93)
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