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Th e main aims of this study were to determine the overwintering form and the primary inoculum of Erysiphe necator, the causal agent of grapevine powdery mildew in southern Syria. Eleven vineyards located at fi ve diff erent geographical sites were visited every week from March to November in 2014 and 2015. Th e results of fi eld and histopathological studies showed that E. necator survived as mycelium in dormant grapevine buds during the winter season. Th e fi rst fl ag shoots were observed shortly aft er bud break in spring. Th e number of fl ag shoots varied greatly according to vineyards, cultivars and years, being present on 27.4 to 61.9% of the grapevines in 2014, and on 5.2 to 40% of the grapevines in 2015. Th e percentage of fl ag shoots on the same grapevine also varied according to the year, cultivar and location. It was between 4.3 to 9.4% in 2014, and 2.1 to 3.6% in 2015. Th e disease was observed only on Balady and Black cultivars. Conidia were released from the second week of May to early September. Th e fi rst conidia were trapped around mid-May, and the fi rst secondary symptoms were observed on leaves from mid-May to early June according to the site. Chasmothecia were observed on leaves in 45.5% of the studied vineyards. Th e fi rst observation of chasmothecia on leaves was in July, and their numbers varied greatly between vineyards and years. Chasmothecia were not detected on bark, nor were ascospores trapped at the beginning of the season. Th ese results confi rmed that the ascospores did not have any role in the initiation of spring infection. To the best of our knowledge, this is the fi rst report of the overwintering form of E. necator in Syria.
The purpose of experiments conducted during five years in an apple orchard and indoor conditions was to economise the collection and introduction of predatory mite (Typhlodromus pyri Scheut. Phytoseiidae), the effective predator of spider mites (Tetranychidae) in the orchards. It was found that collecting T. pyri in cloth belts in orchards was the efficient and economical way to gain high amount of predators for introduction. In order to avoid very high winter mortality of predators in Polish conditions the belts were transfered in autumn from the orchard to the room with stable temperature O°C -+ 1°C and high humidity. Keeping the belts with predators in outdoor condition in polivinyl boxes kept in shadow allowed also to avoid high mortality of overwintering T. pyri.
Ten radio-tagged hedgehogs Erinaceus europaeus (Linnaeus, 1758) were monitored during the winter of 2001/2002 in a Danish rural area. The study was aimed at measuring parameters essential for hibernation success and the fate of the mainly juvenile hedgehogs being recorded. The average duration of hibernation was found to be 179 days for juveniles (n = 6) and 198 days for adult females (n = 3). The most often used nesting habitat types were forested areas (55%). The hedgehogs typically used 2 nests during the hibernation period, but up to 4 different nests used by one hedgehog were found. Time spent in different nests varied considerably (6-187 days). The average weight loss during hibernation was 22.1% for juveniles and 30.2% for adult females. Minimum body mass sufficient for survival was registered to be 513 g prior to hibernation. Nine of the hedgehogs survived until departure from their hibernacula, while the fate of 1 juvenile is unknown. Indication was thus found that the minimum weight required to survive the winter has previously been overestimated.
The study aimed to evaluate the effect of soil application of the humic preparation Humistar and/or foliar application of the potassium fertilizer Drakar on biometric features, overwintering and state of nutrition, as well as the quantity and quality of winter oilseed rape yield. This study was based on a single-factorial field experiment conducted over 2006-2009 in Chrząstowo, on mesic Typic Hapludalf soil of a granulometric composition of light loam, in a randomized block design, in four replications. The effect of the following was evaluated: Humistar (12% humic acids and 3% fulvic acids), applied pre-sowing into soil, at a rate of 40 dm³·haˉ¹ (T1); Drakar (25.7% K and 3% N), applied in autumn after formation of 6 leaves (2 dm³·haˉ¹) and in spring, at the beginning of falling petals (4 l·haˉ¹) (T2); combined application of Humistar and Drakar (T3); and the control (T4). In this study has been shown that Drakar had a positive effect on seed yield of oilseed rape. The use of this fertilizer increased the chlorophyll index in the autumn and improved overwintering in relations to the control only when the earlier application of Humistar was made. Further studies are necessary to evaluate the effect of these preparations in weak soils with low content of organic matter and nutrients.
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Seasonal changes in cryoprotectants concentrations in Helix pomatia snails

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Terrestrial snails are often exposed to freezing. Therefore, we investigated seasonal shifts in hemolymph concentrations of cryoprotectants such as glycerol and glucose. We also investigated whether summer acclimation to cold and short-day photoperiod induced synthesis of cryoprotectants in Helix pomatia snails. Concentrations of the both cryoprotectants were elevated in winter and reduced in summer. These changes, however, were not correlated with shifts in liver glycogen content. Summer acclimation to cold (5°C) and short-day photoperiod evoked a selective increase in glycerol concentration. In conclusion, glycerol may play a role in adaptation of the snails to winter cold and glucose is rather unlikely to provide the cryoprotection.
The aim of the paper was to determine the effect of autumn infestation of leaves for apple cultivars (McIntosh, Idared, Jonagold) on the occurrence of conidia of Venturia inaequalis on twigs. It was found that high infestation of apple leaves in autumn is advantageous to conidia overwintering on twigs. Loosely spread hyphae and conidial spores were more frequently observed on twigs in an orchard where no chemical control was employed. The largest amount of conidial spores was recorded on twigs of unprotected McIntosh apple trees as a result of high infestation of leaves in later autumn. A considerably lower amount of conidia was recorded on twigs of Jonagold apple trees. In orchards under chemical control the conidia wintering occurs less frequently and only if leaves were highly infested in the autumn.
The 1988-1998 study comprised analysis of statistical relation of degree of overwintering (in the 9-degree scale) and of winter damage (in percentages of sown area) of triticale, grown in field trials and in agricultural production to the air and soil thermic conditions and precipitation from December to March in the three distinguished overwintering zones. Also air minimum temperature at 5 cm above the ground, snow cover absent or less than 5cm thick as well as snow cover of different thickness and duration were analysed. It was found that triticale overwintering was determined mainly by air and soil temperature, especially in December and January, whose largest impact manifested itself in the central part of Poland.
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