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natural biological controls with prescriptive chemical input as last reson. The strategy is
primarily based on ultderstandilig the interaction of pest with i(s environment, in the
present context, agro-ecosystem, defined as the effective environment at the crop level
(Altieri, 1994), or at thc level of local lalidscape (Duelli, 1997; Collins and Qualset, 1999).
It is defined that an insect become5 a pest when general equlllbrium populatioll exceeds
econonlic lnjury level (EIL) (Higley and Pedigo, 1996). Exploitat~on of species divers~ty to
decrease Ihe herbivore population was done et'li.ctively (Altier~, 1994). Biodiiersily
increase in agroaosystems results ill di.\~cloplirent of tilore inter~ial links with111 the food
webs resulting in fewer pest oulbreaks (Altieri and Niclrolls, 1999). These understandings
led to some practical approaches such as poly harvesting (Pral~cis, 1990) and interplanting
(Alticri and Whitcoinb, 1980) are potent~al eco-control mcnsurss.
2.3.1.2 Pliysicnl control:
J
Tile methods in lliis strategy are relatively ancicnt, but stood for ayes, as they are
farmer and eco-friendly while bcing easy-to-use. They requ~re leaser scientific kriowledge
and are based on physical destructioli of inscct populations. These havc attracted
considerable attention In the recent past because of the development of effective food and
visual attractants (Lindgren and Fraser, 1994). Understanding the insect behavior is a
crucial prerequisite for making traps (Alm et al, 1994). Usage of baits such as pheromones
and novel trap designs made insect trapping devices attractive tools in the industrial point
of view (Dowdy and Mullen, 1998). Usage of some sort of banding material especially
arourid the trunks of the trees had some degree of antagonist effect on insects (Raupp et al,
1992). Live stock insect traps (Tozer and Sutherst, 1996), colored traps (Vernon and
Broatch, 1996), arid fermentation traps (Norris, 1933) are some of the effecttve