A Survey of Scale Insects (Sternorryncha: Coccoidea) Occurring on Table Grapes in South Africa

Increasing international trade and tourism have led to an increase in the introduction of exotic pests that pose a considerable economic threat to the agro-ecosystems of importing countries. Scale insects (Sternorryncha: Coccoidea) may be contaminants of export consignments from the South African deciduous fruit industry to the European Union, Israel, United Kingdom and the United States, for example. Infestations of immature scale insects found on South African fruit destined for export have resulted in increasing rates of rejection of such consignments. To identify the risk posed by scale insect species listed as phytosanitary pests on table grapes to the abovementioned importing countries, a field survey was undertaken in 2004–2005 in vineyards throughout all grape-producing regions in South Africa. Coccoidea species found during the current field survey were Planococcus ficus (Signoret), Pseudococcus longispinus (Targioni Tozzetti), Coccus hesperidum L. and Nipaecoccus viridis (Newstead). With the exception of Pl. ficus, which has only been collected from Vitis vinifera (Vitaceae) and Ficus carica (Moraceae) in South Africa, these species are polyphagous and have a wide host range. None of the scale insect species found to occur in vineyards in South Africa pose a phytosanitary risk to countries where fruit are exported except for Ferrisia malvastra (McDaniel) and N. viridis that have not been recorded in the USA. All scale insects previously found in vineyards in South Africa are listed and their phytosanitary status discussed. The results of the survey show that the risk of exporting scale insect pests of phytosanitary importance on table grapes from South Africa is limited

Genomic organisation of the Mal d 1 gene cluster on linkage group 16 in apple

European populations exhibit progressive sensitisation to food allergens, and apples are one of the foods for which sensitisation is observed most frequently. Apple cultivars vary greatly in their allergenic characteristics, and a better understanding of the genetic basis of low allergenicity may therefore allow allergic individuals to increase their fruit intake. Mal d 1 is considered to be a major apple allergen, and this protein is encoded by the most complex allergen gene family. Not all Mal d 1 members are likely to be involved in allergenicity. Therefore, additional knowledge about the existence and characteristics of the different Mal d 1 genes is required. In the present study, we investigated the genomic organisation of the Mal d 1 gene cluster in linkage group 16 of apple through the sequencing of two bacterial artificial chromosome clones. The results provided new information on the composition of this family with respect to the number and orientation of functional and pseudogenes and their physical distances. The results were compared with the apple and peach genome sequences that have recently been made available. A broad analysis of the whole apple genome revealed the presence of new genes in this family, and a complete list of the observed Mal d 1 genes is supplied. Thus, this study provides an important contribution towards a better understanding of the genetics of the Mal d 1 family and establishes the basis for further research on allelic diversity among cultivars in relation to variation in allergenicity