There is a need to develop new ways of protecting plants against aphid attack. Here, we investigated the effect of a plant defence activator, cis-jasmone (CJ), in a range of cultivars of Brassica napus, Brassica rapa and Brassica oleracea. Plants were sprayed with cis-jasmone or blank formulation and then tested with peach potato aphids (Myzus persicae Sulzer) (Hemiptera: Aphididae) and their parasitoid Diaeretiella rapae (M'Intosh) (Hymenoptera: Braconidae). CJ treated plants had significantly lower aphid settlement than control plants in a settlement bioassay. Conversely, in a foraging bioassay, D. rapae parasitoids spent a significantly longer time foraging on CJ treated plants. Our results reveal that CJ treatment makes plants less attractive to and less suitable for M. persicae but more attractive to D. rapae in a range of brassica cultivars. It is likely that these effects are due to changes in volatile emission indicating activation of defence and presence of conspecific competitors to aphids but presence of prey to parasitoids. Increases in volatile emission were found in CJ induced plants but varied with genotype. Among the synthetic volatile compounds that were induced in the headspace of CJ treated brassica cultivars, methyl isothiocyanate, methyl salicylate and cis-jasmone were most repellent to aphids. These results build on earlier studies in Arabidopsis and show that tritrophic interactions are influenced by CJ in a wide range of brassica germplasm. The implication is that CJ is a promising treatment that could be used in brassica crops as part of an integrated pest management system.

The greenhouse whitefly Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) is a pest of a wide range of vegetable and ornamental crops in greenhouses around the world. Yellow sticky traps are highly attractive to flying adults and so are frequently used to monitor the pest. Our aim was to test whether changes in trap translucency or the addition of printed black patterns could increase the catch on yellow sticky traps in greenhouses. Field trials were carried out in commercial crops of strawberry and tomato under glass over three years. Reduced trap translucency increased trap catches by a factor of 1.5 to 7.0 and the catch increased significantly for both females and males. Spectrometer measurements showed that the increased catch was consistent with an increased landing stimulus from a colour opponency mechanism i.e. the ratio of energy from 500–640 nm to the energy from 300–500 nm. Printed black patterns increased trap catches on specific types of trap, by a factor of 1.4 to 2.3, and the catch increased significantly for both females and males. The patterns increased trap catch on moderately translucent traps, but decreased trap catch on less translucent traps. The evidence points to a contrast/edge effect of pattern, but laboratory experiments are needed to clarify this. Exploitation of these translucency and pattern effects could improve the efficacy of yellow traps for monitoring and mass trapping in crops.

Frankliniella occidentalis  (Pergande) (Thysanoptera: Thripidae) adult male has sternal glands whose role is to produce pheromones. It is known that there are two major components in the headspace volatiles of thrips adult male that are not present in the headspace volatiles of adult female. Those components, (R)-lavandulyl acetate and neryl (S)-2-methylbutanoate were synthesized for the first time in Romania by "Raluca Ripan" Institute for Research in Chemistry (Cluj-Napoca). We have tested a blend of those in the greenhouse cucumber ( Cucumis sativum ) crops of University of Agricultural Sciences and Veterinary Medicine. Period study lasted in 4 weeks. Blue sticky traps were coated with insect glue on both surfaces and a rubber septum which contained the blend was attached in the center of a side of a trap. Two traps with pheromone lure and one trap without pheromone lure were hung up to a 20 cm distance from the tip of the plant. Both female and males were trapped. We observed a higher percentage of males on pheromone trap. Our data revealed that the total number of western flower thrips caught on pheromone traps ranged between 1537 and 1941 as compared with the total number of thrips caught on control trap (1333). According to our results we conclude that pheromone traps could be effective tools for F. occidentalis mass trapping and for the use in integrated pest management strategies.

Frankliniella occidentalis  (Pergande) (Thysanoptera: Thripidae) is an important pest in vegetable and ornamental greenhouse crops due their direct damage by feeding and indirect damage by vectoring Tomato Spotted Wilt Virus (TSWV). Also, is very well known that they have an extremely high resistance to a wide range of insecticide. Thus by monitoring thrips population appropriate control plans can be established. Western flower thrips was reported in all greenhouses from Cluj County (Romania). In order to assess thrips population dynamic and color preference we conducted a research in a plastic greenhouse of 8000 m 2 placed outside of Cluj-Napoca where the main cultivated crops were tomatoes ( Solanum lycopersicum ) and the main thrips pest found was western flower thirps. During the sample period pest population was monitored weekly using two methods: by counting thrips trapped on five different colored sticky cards (blue, yellow, white, red and transparent) and by a technique based on leaves tapping. Data analysis showed no correlation between traps and tapping method. Blue and yellow traps had the highest attractiveness compared with all the others colors and between those, blue proved to be the most effective.

Western flower thrips, Frankliniella occidentalis (Pergande) is an important crop pest and a vector of tomato spotted wilt virus (TSWV) in many areas of the world. Its feeding can cause scarring and deformations on leaves and fruit, with seedlings and soft tissue particularly prone to feeding damage. Cucumbers and other vegetable are susceptible to fruit scarring. Population dynamics of western flower thrips was monitored both in field and protected spaces throughout different methods and on different ornamental and vegetables hosts. In this paper results regarding population dynamic on cucumber greenhouse crop are presented. Studies were conducted throughout five weeks. Shaken method was used. Ten leaves from the bottom of the plant, ten from the middle, ten from the tip of the plant and ten flowers were weekly sampled. Mean temperature and treatments applications were recorded. The fallen larvae and adults were counted. Females and males were separately noted. Sex ratio influence and spatial distribution was also followed. Data analysis demonstrated that thrips preferred to feed on younger leaves situated on tip of the plant. There was a very low difference between sex ratio in leaves as compared with the one in flowers. Regarding population dynamics of thrips on whole study period the trend was of increasing, thus treatment application were less efficient and proves its high pesticide resistance character.