Quality of Intensively Produced Crops

Farmers and growers are seeking higher crop yields to help balance increasing productions costs. Methods/practices used to increase yield include crop zoning to suitable climates (Bunting et al., 1982), improved cultivars, higher applications of fertilizers and agrochemicals, use of growth promoters/ripening agents, using modified soil management practices, growing in different media, modifying atmospheres and controlling temperature in protected cultivation, and through using irrigation and higher plant densities. These methods/practices, while increasing yield, may lower the sensory quality of the crop and adversely affect composition. In the period 1961-1979 the world cereal grain yield per hectare (ha) has increased by 26% with an increase of 42& for millet (MacKey, 1981); in the last 10 years the yield of greenhouse tomatoes in Ireland has risen by 30% to about 250t/ha (Gornley, 1982). Similar increases have been recorded with many other crops. However, crop yields are often inversely related to quality (MacKey, 1981; Gormley et al., 1973, 1982) and there are increasing consumer complaints about the quality of intensively produced food, i.e. that fruit, vegetables and other foods do not have the flavour they had when yields were lower and agricultural practices les intense; this has led to an upsurge in the demand for organically grown foods in some countries (Kramer, 1973; Knorr, 1979). The Commission of the European Communities (1978,1983) has expressed its concern on the intensity versus quality issue by launching a research programme o this topic in member states; the sensory and compositional aspects of intensively produced apples, tomatoes and poultry are being studied and it is proposed to include beef and potatoes in future programmes. Saurer (1981) has discussed some of the effects of modern agricultural methods on the quality of cereals and vegetables while Stoll (1969) emphasised the detrimental effects of excessive fertilizer applications on crop quality. This discussion examines some of the effects of intensive production methods on the quality of plant foods; this is a wide topic and only superficial coverage can be given to many of the aspects. Most attention is given to studies where a significant amount of quality evaluation of the food produced, in terms of sensory and/or chemical and/or physical analyses, has been carried out. The impact of plat breeding and cultivars, as part of the intensive production system is not discussed in view of the extensive nature of this area. However, it is important to note that there is considerable emphasis on breeding for high quality in addition to yield (Axtel, 1981) in many crops, including apples (Alston, 1981), legumes (Milner, 1973), cereals (Doussinault et al, 1975) and strawberries (MacLachlan, 1981).