Dr+Dhaliwal+article - Indian J Ecol(2010 37(1 1-7 Indian...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Green revolution has no doubt led to increased world food supplies, but at the same time it has caused several ecological, environmental and socioeconomic problems. Green revolution technology relied on the use of dwarf and semi dwarf high-yielding varieties of crops, increased use of agrochemicals and irrigation. All these practices favoured the build-up of crop pests, with the result that the intensity of several pests has increased, many minor pests have assumed the status of major pests and several new pest problems have appeared in certain regions. In addition, the misuse and overuse of pesticides has lead to problems of pesticide resistance, resurgence and contamination of different components of the environment. In spite of a variety of control measures applied against pests, crop losses have consistently shown an increasing trend (Dhaliwal and Koul, 2010). The introduction of gene technology has added a new dimension to pest management. There are varied claims and counter-claims about the potential of gene technology in shaping the crop protection scenario in the twenty-first century (Dhaliwal, 2008; James, 2009). In addition, the climate change exerts a profound effect on the intensity of pest problems (Ramamurthy et al. , 2009). Hence, there is considerable shift in insect pest problems and crop losses, which form the focus of this paper. Pest Problems Food plants of the world are damaged by more than 10,000 species of insects, 30,000 species of weeds, 100,000 diseases (caused by fungi, viruses, bacteria and other microorganisms) and 1000 species of nematodes (Hall, 1995; Dhaliwal et al. , 2007). However, less than 10 per cent of the total identified pest species are generally considered as major pests. The severity of pest problems has been changing with the developments in agricultural technology and modifications of farming practices. The changing scenario of insect pest problems in agriculture as a consequence of green revolution technology has been well documented (Dhaliwal et al., 1985; Singh and Dhaliwal, 1991; Dhaliwal and Arora, 1993; Arora and Dhaliwal, 1996; Dhaliwal et al., 2002; Singh et al., 2002; Puri and Mote, 2003; Kumar, 2005; Dhaliwal and Arora, 2006; Dhaliwal and Koul, 2010). There has been further shift in the status of several insect pests after the introduction of transgenic crops and the current scenario of climate change. The pest scenario in cotton ecosystem is changing fast and is assailed by multitude of pests as it evolves through various production levels. American and spotted bollworms attained secondary pest status, and tobacco caterpillar, pink bollworm, mirids and mealy bugs are emerging as major pests. Sap sucking pests like aphids, jassids, thrips and whiteflies are major pests and economically important. Adoption of Bt cotton has not only changed the cultivation profile, but also the pest scenario.
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern