Transgenic crops offer a complex new technology that is not universally dominant over alternatives. Instead, adoption decisions are conditional on incentives associated with alternative technologies and local conditions. These characteristics imply that transgenic crops can be expected to be adopted on a wide scale in existing cultural areas, if incentives are appropriate. Further, considerable...

There are various designs of tools and equipment used for harvesting the crops and threshing it separately. Sickles, hand tools and reapers for grain crops and diggers for tuber crops and rhizomes, operated with different power sources are used. Combine harvesters, both tractor mounted and self-propelled, are being very widely used for different grain crops. Functional requirements and principl...

Root crop production in Papua New Guinea is reviewed. Crops considered are the major ones (Ipomoea batatas, Colocasia esculenta, Dioscorea aiata, D. escuienta, Xanthosoma sagitti!olium), other significant root crops (Manihot esculenta, Psophocarpus tetragonolobus, Cyrtosperma chpmissonis., Alocasia macro"htza and Solanum tuberosum) and 27 minor crops. For the major and significant crops, aspect...

Plant virus diseases cause severe constraints on the productivity of a wide range of economically important crops worldwide. In India the Green Revolution ushered in intensive agricultural practices and reduced varietal diversity, resulting in the emergence of viral diseases at an alarming pace in the cultivated crops. Some such diseases, which are especially relevant to India, along with their...

Through the use of the new tools of genetic engineering, genes can be introduced into the same plant or animal species or into plants or animals that are not sexually compatible-the latter is a distinction with classical breeding. This technology has led to the commercial production of genetically engineered (GE) crops on approximately 250 million acres worldwide. These crops generally are herb...

Herbicide tolerant (HT) crops are not a new phenomenon – in fact, all crops are to some extent tolerant to herbicides. Many herbicides are dose-specific for particular plant groups, for example grasses, and these can be used on broad-leaved crops like potatoes and oilseed rape without causing unacceptable harm. This is the basis for most current agricultural practice in developed countries. Gen...

Cover crops constitute one of the most promising agronomic practices towards a more sustainable agriculture. Their beneficial effects on main crops, soil and environment are many and various, while risks and disadvantages may also appear. Several legumes show a high potential but further research is required in order to suggest the optimal legume cover crops for each case in terms of their prod...

Claims have been made recently that glyphosate-resistant (GR) crops sometimes have mineral deficiencies and increased plant disease. This review evaluates the literature that is germane to these claims. Our conclusions are: (1) although there is conflicting literature on the effects of glyphosate on mineral nutrition on GR crops, most of the literature indicates that mineral nutrition in GR cro...

Hectares of genetically modified (GM) crops have increased exponentially since 1996, when such crops began to be commercialized. GM biotechnology, together with conventional breeding, has become the main approach to improving agronomic traits of crops. However, people are concerned about the safety of GM crops, especially GM-derived food and feed. Many efforts have been made to evaluate the uni...

The intensification of agriculture has provided cheaper more plentiful food, but has also caused declines in farmland wildlife. The introduction of genetically modified (GM) crops may exacerbate this, or offer new ways of mitigating anthropogenic impacts. The potential consequences of the introduction of GM crops have been studied for over a decade, since commercialization. Although the specifi...