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Western flower thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), are one of the most serious pests of horticultural crops worldwide. Despite one third of its lifecycle being in the soil, the potential for biological control of WFT in the soil is poorly understood and requires further elucidation. A number of studies report that polyphagous predatory mites prey on pupal stages of WFT in the soil, but little has been done on consumption rates. Therefore, we designed a laboratory study to examine the rate of consumption of WFT pupae in potting media, by the soil-dwelling mite Hypoaspis sclerotarsa (Costa). Five predator densities were evaluated (0, 2, 4, 6 and 8) against four densities of WFT prey (5, 10, 15 and 20 pupae). Pupal consumption was assessed at 2 hourly intervals over a six-hour period. The study confirmed that H. sclerotarsa did consume WFT pupae and that the rate of consumption increased with increasing density of H. sclerotarsa. The rate of consumption also increased with the density of WFT pupae. However, this was not consistent because, as the numbers of WFT pupae increased, so did the ratio of WFT pupae remaining to those consumed, increase. This paper is the first report of H. sclerotarsa in Kenya, and of its potential as a biocontrol agent of WFT. Further studies are now needed to understand interaction of foliar and soil dwelling predatory mites (H. sclerotarsa) for control of WFT under field conditions. [ABSTRACT FROM AUTHOR]

This article explores innovation and technology development aid targeted at the African rural poor but often failing to deliver benefit. Using five cases of UK bilateral aid (current and historic) it suggests the prime importance of securing continuous knowledge interaction across the whole of the relevant value chain, combined with the need for institutional reform of science policy in this field. The article's approach emphasizes the underlying problem as an inherent tendency to failure in knowledge markets combined with often unsuitable institutional contexts. [ABSTRACT FROM AUTHOR]

This report quantifies the variation in fruit physio-chemical characteristics of five cultivars of gooseberry (Ribes uva-crispa). Each cultivar was completely harvested when 20% of the fruit on a bush were evaluated to be ripe. Harvest dates varied from 15 June ('Rokula') to 8 July for 'Greenfinch'. 'Invicta' gave the largest fruit but was the least sweet, 'Leveller' had the smallest fruit and 'Greenfinch' the sweetest. Fruit color changed with fruit size, especially for the red cultivars, 'Rokula' and 'Pax'. However, fruit size was not a good indicator of fruit sweetness. Selecting fruit on the basis of firmness and color rather than fruit size was a more accurate indicator of fruit sweetness and therefore consumer acceptability. Further investigation is required to determine quantifiable thresholds in terms of color, sweetness and/or firmness whereby a gooseberry is considered acceptable to the consumer as a fresh dessert fruit. The thresholds are likely to be specific to the cultivar. [ABSTRACT FROM PUBLISHER]