A new invasive species, the Japanese grape leafhopper, Arboridia kakogawana (Matsumura). is reported for the first time in Romania. Arboridia kakogawana is a serious pest of grapevine (Vitis vinifera L.) in East Asia (South Korea and China) and in Southern Russia (Krasnodar and Rostov regions) and Ukraine. In 2018, very high numbers of A. kakogawana were caught on yellow sticky traps in a vine plot in Romania in Northern Bucharest. Adults were trapped from early June to the middle of November. The dynamics of the adult population were measured using yellow sticky traps, and in 2018 four peaks were observed in the middle of July, in the first 10 days of August, at the beginning of September and in the first 10 days of October. The first overwintering adults appeared from the beginning of June. Foliar symptoms associated with the trophic activity of the leafhopper were observed on grapevine and Virginia creeper (Parthenocissus quinquefolia (L.)). Yellow sticky traps used in prior studies in the Bucharest area were re‐examined and the Japanese leafhopper was discovered on these, which leads to the conclusion that the species has been present at least since 2016 in this area. This is the first report of A. kakogawana in Romania and in the European Union.

Grapevine yellows are a group of infectious diseases, which are usually associated with phytoplasma pathogens, affecting quality of grapes and survival of grapevine. The objective of this work was to evaluate sugars, total phenols and organic acids concentrations in the grapes of four wine cultivars (Fetească Neagră, Pinot Noir, Traminer rose, Chardonnay) healthy and affected by specific symptoms to phytoplasmoses. Berry samples were collected from the Miniș-Măderat (Arad County) and Odobești (Vrancea County) vineyards. Individual sugars and organic acids compounds were identified and quantified in grape berries by the high performance liquid chromatography (HPLC) method using DAD and RID detectors, while total phenolic compounds by using spectrophotometry. The content and composition of sugars and acids varied between healthy and symptomatic plants. Analysis of grape juice revealed reduction in sugars (fructose and glucose) from symptomatic to non-symptomatic vines. Lower values of acidity were obtained in grapes of affected compared to non-affected vines. The differences in acids content between grapes of affected and not affected vines were more pronounced at Pinot Noir variety, with lower concentrations of malic and tartaric acids in grapes from symptomatic vines in both locations studied. The affected grapes did not differ significantly from the healthy ones, regarding to succinic acid content. A notable increase of total phenolic compounds was observed in symptomatic compared to asymptomatic grape berries. The results of this paper showed a clear negative effect of the phytoplasmoses symptoms on grape fruits composition.

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The need for efficient technologies to enhance productivity in agriculture strongly motivates research on plasma treatment of seeds and plants. In this study, the influence of plasma treatment on sunflower (Helianthus annuus L.) seeds was evidenced throughout the entire life span of the plants. The seeds were packed in a DBD reactor operated in air and treated in plasma for 10 min, using a sinusoidal voltage of 16 kV amplitude at 50 Hz frequency. Early growth observation of plants under laboratory conditions showed that, after a slower start, the plasma-treated seeds developed faster and produced taller seedlings with greater total mass as compared to the control samples. Results obtained from mature plants cultivated in the field revealed a positive effect of plasma exposure with respect to capitulum size, number of seeds per capitulum and mass per thousand seeds, resulting in a remarkable increase in crop yield. The plasma effect lasted for at least two weeks of seed storage; however, it was considerably affected by the sowing period.

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