Спектрофотометрическая характеристика антоцианов плодов черешни белорусской селекции

Приведены экспериментальные данные рН дифференцированного спектрофотометрического метода определения антоцианов в плодах черешни. Выявлена сортоспецифичность содержания антоцианов, даны рекомендации по практическому применению результатов

Oxidative stress in soybean seedlings treated with Thymus serpyllum aqueous extract

The effect of different concentrations (0.05, 0.1 and 0.2%) of Thymus serpyllum L. aqueous extracts on lipid peroxidation process (LP), as well as reduced glutathione content (GSH) in leaves and roots of soybean seedlings were examined 24 and 72 h after the treatment. Our results showed that only highest concentration of the extract used (0.2%) enhanced process of lipid peroxidation, while concentration of 0.1% stimulated GSH accumulation in soybean seedlings

Effects of different inert dusts on Sitophilus oryzae and Plodia interpunctella during contact exposure: Poster

The use of natural inert dusts against storage insect pests is increasing recently, as an alternative to conventional insecticides. Laboratory study was carried out to evaluate the contact effect of three inert dusts, diatomaceous earth (DE), kaoline (KA) and vermiculite (VE), at rates 5, 7.5, 10, 15 and 20 gm-2, against adults of Sitophilus oryzae (L.) and larvae of Plodia interpunctella (Hubner). Insect mortality was evaluated 1, 2, 3 and 7 days after the exposure. Insect mortality varied depending on the species, concentrations and exposure periods. The DE and KA caused 86.7-98% mortality of S. oryzae after 2 days of exposure at the highest rates, while at 5 and 7.5 gm-2, 100% mortality was achieved only after 7 days. The highest rates of inert dusts caused 42-50% (DE) and 60-75% (KA) mortality of P. interpunctella larvae only after 7days. The mortality of moths increased gradually with the concentration and 100% was achieved 3 days after the contact with DE and KA (10, 15 and 20 g m-2). However, inert dusts induced faster pupation of P. interpunctella, while adult emergence was reduced and adults had smaller body-sizes, compared to control. The VE caused relatively low mortalities (7-11% of S. oryzae adults and 5-8% of P. interpunctella larvae) at all tested rates during the entire experiment. Our results have shown good insecticidal effect of DE and KA against S. oryzae and P. interpunctella at 10, 15 and 20 gm-2. These products could therefore be used by small-scale farmers to protect stored grains against insect pest infestation.The use of natural inert dusts against storage insect pests is increasing recently, as an alternative to conventional insecticides. Laboratory study was carried out to evaluate the contact effect of three inert dusts, diatomaceous earth (DE), kaoline (KA) and vermiculite (VE), at rates 5, 7.5, 10, 15 and 20 gm-2, against adults of Sitophilus oryzae (L.) and larvae of Plodia interpunctella (Hubner). Insect mortality was evaluated 1, 2, 3 and 7 days after the exposure. Insect mortality varied depending on the species, concentrations and exposure periods. The DE and KA caused 86.7-98% mortality of S. oryzae after 2 days of exposure at the highest rates, while at 5 and 7.5 gm-2, 100% mortality was achieved only after 7 days. The highest rates of inert dusts caused 42-50% (DE) and 60-75% (KA) mortality of P. interpunctella larvae only after 7days. The mortality of moths increased gradually with the concentration and 100% was achieved 3 days after the contact with DE and KA (10, 15 and 20 g m-2). However, inert dusts induced faster pupation of P. interpunctella, while adult emergence was reduced and adults had smaller body-sizes, compared to control. The VE caused relatively low mortalities (7-11% of S. oryzae adults and 5-8% of P. interpunctella larvae) at all tested rates during the entire experiment. Our results have shown good insecticidal effect of DE and KA against S. oryzae and P. interpunctella at 10, 15 and 20 gm-2. These products could therefore be used by small-scale farmers to protect stored grains against insect pest infestation

Effect of auxins on mechanical injury induced oxidative stress in Prunus sp. Rootstocks

The effect of exogenously applied auxins on oxidative stress was studied in six rootstock selections of Prunus cerasus, P. mahaleb and P. fruticosa aiming at the effect of phytohormones on the level of the lipid peroxidation (LP). Standard rootstock PHL-A was used as a control. Leaves were collected on 0, 1st, 3rd and 7th day of inserting cuttings into the rooting substrate. Auxin mixture consisted of 0.8% α-naphthylacetic acid and 0.5% indolebutyric acid. Differences in intensity of the LP between auxin-treated and -untreated cuttings were examined. Almost all of investigated selections had lower LP intensity after auxin application (11.4-47.2%). The most prominent change was in leaves of PHL-A (49.2%). LP-lowering effect were recorded in leaves of P. fruticosa (56.9%) on 7th day and in P. mahaleb on 1st and 3rd day (5.9, 5.8%). Intensity of LP could be used as one of the biochemical parameters in further rootstock selection and production

Chemical composition of Clinopodium menthifolium aqueous extract and its influence on antioxidant system in black nightshade (Solanum nigrum) and pepper (Capsicum annuum) seedlings and mortality rate of whitefly (Trialeurodes vaporariorum) adults

The use of allelochemicals as weed control agents is becoming widely investigated. However, the impact of these bioherbicides on cultivated plants is less known. This study was carried out in order to evaluate the allelopathic effects of the aqueous extract of Clinopodium menthifolium on black nightshade (Solanum nigrum) antioxidant properties to explore the potential of this species in weed control and on pepper (Capsicum annuum) antioxidant properties so as to assess its possible side effects when applied as bioherbicide in organic production. Taking into account that plant extracts should be an alternative source for insect control, additional aim was also to evaluate contact effect of C. menthifolium aqueous extract against the greenhouse whitefly (Trialeurodes vaporariorum). Analysis by HPLC confirmed the presence of gallic acid, caffeic acid and 2-hidroxy-cinnamic acid as major components in the C. menthifolium aqueous extract. Both tested concentrations of C. menthifolium aqueous extract induced lipid peroxidation in black nightshade leaves and roots. It was observed that the aqueous extract with a concentration of 0.1% showed a toxic effect with 50% mortality of greenhouse whitefly adults