Crop protection: a consideration of the effectiveness and disadvantages of current methods and of the scope for improvement

Abstract

Ideally crop protection should prevent damaging effects of pests, diseases and weeds economically, safely and without harming the environment or inducing subsequent control problems. Present methods, based mainly on pesticides and resistant crop varieties, control many damaging organisms effectively but have important limitations. Vulnerability to the emergence of tolerant strains of pest or pathogen is probably the most severe; chemical methods are also often insufficiently selective and very wasteful. Dependence on these methods will continue, however, and it is therefore essential to seek ways of minimizing their deficiencies. The prospects for improvement are discussed in relation to the need for better intelligence about infestations and their consequences, the need to ensure that control measures remain effective and the need to improve the efficiency of utilization of crop protection agents. Implementation of the suggestions for improvement could require fundamental changes in the organization of crop protection practices.

REVIEW: An overview of the environmental risks posed by neonicotinoid insecticides

“…Thus, although seed dressings are often stated to provide accurate targeting of the crop (e.g. Jeschke et al 2011), they result in a considerably smaller proportion of the active ingredient ending up in or on the crop than do traditional spray applications to foliage, which commonly exceed 50% efficiency (Graham-Bryce 1977).…”

Measuring pesticide ecological and health risks in West African agriculture to establish an enabling environment for sustainable intensification

“…These risks are widespread and often severe because of the nature of pesticide use and the properties of the pesticides themselves [4][5][6]. Pesticide application is highly inefficient [7,8] and the chemical properties that enable them to partition between air, soil, water and the pest biota to exert impacts on target species [9,10] may also allow transport beyond the treated site to neighbouring habitats, to ground and surface waters [11,12], and in some cases to globally distant marine and terrestrial ecosystems [13,14]. Pesticides are rarely specific to target species, and organisms that pose no threat to agricultural yields or public health may also be susceptible and succumb to toxic impacts as a result of being exposed [5,15].…”

Investigation of Spray Application of Microbial Herbicides Using Alternaria alternata on Amaranthus retroflexus

“…Although losses of chemical herbicide during spraying (by drift, lack of retention or run-oV) are well documented (Graham-Bryce, 1977;Gohlich, 1985;Knoche, 1994), this is the ® rst report that similar levels of conidial loss occur during spraying of a microbial herbicide. Also, this loss is relatively more important than that of chemical herbicides, as the eVectiveness of retained conidia is much more sensitive to environmenta l constraints than the chemical.…”