Crop protection biological control

Biological control is never complete. The degree of control fluctuates. There is always a time lag between pest population increase and the corresponding increase in natural controls. But, under proper conditions, sufficient control can be achieved to eliminate the threat to the crop or animal needing protection. Biological control can be a low-cost control method particularly suited to low-value crops (pastureland, clover, and hay crops) or in areas where some injury can be tolerated (golf course fairways or forest areas). 

The total amount of pesticide applied worldwide, as mentioned, is estimated to be 2.5 million tons. Of this 50 to 60% are herbicides, 20 to 30% are insecticides, and 10 to 20% are fungicides. Interestingly, less than one-third of all the agricultural cropland in the world is treated with some kind of pesticide. This illustrates the fact that a significant portion of crops receive no pesticide and, therefore, are protected to some extent by nonchemical biological controls. 

Owing to the prohibition of chemosynthetic pesticides under organic farming standards, there is a greatly reduced availability of intervention/treatment-based methods for disease and pest control in organic fruit production systems. The efficacy of the permitted biological control, extract or mineral element (e.g. S and Cu)-based crop protection products is also usually lower than of chemosynthetic pesticides. Permitted plant protection products show efficacies of between 60 and 80% while chemosynthetic fungicides and pesticides often have efficacy levels >95% (Tamm et al., 2004). 

Glen DM, Wilson MJ, Pearce JD, Rodgers PB. (1994) Discovery and investigation of a novel nematode parasite for biological control of slugs. In Proceedings of the Brighton Crop Protection Conference, pests and diseases, pp 617-624. 

Nilsson U, Gripwall E. Influence of application technique on the viability of biological control agents Verticillium lecanii and Steinemema feltiae. Crop Protect. 1999 18 53-59. 

Cucumber mosaic virus pictured on p.89) can, despite its name, affect all members of this family, and many other plant families, too. There Is no cure, but some cultivars show some resistance. Protect young plants from slugs. Powdery mildew may be a sign of dry soil late In the year It will not affect the crop. Under cover, biological controls can be used to control pests like red spider mite. Crop rotation, good... 

Pesticides are chemical or biological substances intended to control weeds, insects, fungi, rodents, bacteria, and other pests. They protect food crops and livestock, control household pests, promote agricultural productivity, and protect public health. The importance of pesticides to modern society can be summarized by a statement made by Norman E. Borlaug, the 1970 Nobel Peace Prize winner Let s get our priorities in perspective. We must feed ourselves and protect ourselves against the health hazards of the world. To do that, we must have agricultural chemicals. Without them, the world population will starve [1]. 

Altieri, M.A. and Letourneau, D.K. 1982. Vegetation management and biological control in agroecosystems. Crop Protection 1(4) 405-430. 

Herrington PJ, EC Hislop, NM Western, KG Jones, BK Cooke, SE Woodley and AC Chappie, 1981. Spray factors and fungicidal control of apple powdery mildew. In ESE Southcombe (ed.), Application and Biology. Proceedings of a Symposium held at the University of Reading, Berkshire 7th-9th January 1985. British Crop Protection Council, BCPC Monograph No. 28, Croydon, UK, 1985, 289-298. 

Zande JC van de, 1995. Deposit measurements and biological efficacy, the effects of volume rates and air assistance on weed control. Proceedings, Brighton Crop Protection... 

Zande, JC van de, R Meier and MT van IJzendoom, 1996. Spraying in-field vegetables deposit and biological efficacy, the effects of volume rates, dose, spray interval and air assistance on disease control. BCPC Conference — Pests and Diseases 1996, Brighton 18-21 November 1996, British Crop Protection Council, Famham, 343-348. 

Zdarkova, E. and Horak, E. (1990) Preventative biological control of stored food mites in empty stores using Cheyletus eruditus. Crop Protection 9, 378-382. 

Gurney, B. and N. W. Hussey. 1970. Evaluation of some coccinellid species for the biological control of aphids in protected cropping. Ann. Appl. Biol. 68 451-458. 

The authors discuss three examples of biological control of soil borne diseases. The first is the control of Fusarium wilt of sweet potato by cross-protection that involves a prior inoculation of nonpathogenic Fusarium oxysporum(Ogawa et ai., 1984)(1). The second is the control of Fusarium wilt of bottle gourd by mixed-cropping with associate crops(Kijima et al., 1986)(2). The third is the seed bulb bacterization for the control of root rot of edible lily(Hasegawa et al, 1990)(3). 

The need to control aphids with crop protection chemicals is evident from the difference in yield loss between treated and untreated crops (6). (see Table-II). A wide variety of insecticides are currently available for aphid control but an ideal insecticide should have new chemistry, biological selectivity, good mammalian toxicology profile, aphicidal spectrum and efficacy at low use rate, and safety toward beneficial insects. RH7988 has more of these desirable properties than the currently available aphicidal insecticides. 

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