Emilija Raspudić

Distribution of Aeolothrips intermedius Bagnall (Thysanoptera: Aeolothripidae) and its potential prey Thysanoptera species on different cultivated host plants

The results of the monitoring of Thysanoptera species on cultivated plants in Slovenia (2000–2001), Croatia (1994–1996), and Serbia and Montenegro (1988–2003) are presented in this study. The aim of the investigation was to study the host plant distribution of the predator Aeolothrips intermedius Bagnall and its potential prey. Banded thrips were found on 30 different host plant species belonging to 16 botanical families, always in mixed populations with phytophagous or facultative phytophagous insects (including 18 Thysanoptera species). On the vegetative parts of the cultivated plants, banded thrips were found less numerous in spite of the massive population of some harmful thrips species. This indicates highly important role of pollen as alternative food for Aeolothrips intermedius.

Growth and yield of grafted cucumbers in soil infested with root-knot nematodes

The aim of this study was to determine the effect of rootstocks on the growth and yield of cucumber (Cucumis sativus L.) plants in soils infested with root-knot nematodes (Meloidogyne spp.) Cucumber ‘Adrian’ was grown with its own roots or was grafted onto three rootstocks of Lagenaria siceraria (Molina) Standl. (‘Emphasis’, ‘S-1’, and ‘Gourd’), two interspecific hybrid rootstocks of Cucurbita maxima Duchesne × C. moschata Duchesne (‘Strong Tosa’ and ‘RS 841 Improved’) and zucchini Cucurbita pepo L. (‘Romanesco Zucchini’). The experiments were conducted in commercial greenhouse, with cucumber grafted onto three rootstocks in the first season and onto six rootstocks in the second spring-summer season. The number of leaves was considerably affected by the rootstock in both seasons, and was the highest for the plants grafted onto interspecific rootstocks (28.0 in the first and 44.9 in the second season). The plants grafted onto ‘Strong Tosa’ had higher total number of fruits (19.9) and yield (5.38 kg) compared to other rootstocks or non-grafted plants in first season, and the same result was found for two interspecific rootstocks in the second season (6.96 kg and more than 28.9 fruits per plant). The total soluble solids, pH and electrical conductivity of the fruit were not affected by rootstock, while titratable acidity changed with the rootstock type. The grafting of cucumber plants onto different rootstocks was confirmed as an acceptable non-chemical method to compete with the limitations of soils infected with root-knot nematodes, but the effect was highly dependent on the choice of the rootstock.