Conservation of fruit tree biodiversity is important for the mankind according to the Convention on Biological Diversity. In Romania, due to favorable environmental conditions, numerous genetic resources of plum, apple, walnut, hazelnut, sweet chestnut and other fruit crops are present. Identification, evaluation and conservation of fruit genetic resources activities were launched in 1970' in order to limit the loss of the biodiversity due to erosion and genetic vulnerability.

The walnut leaves and the green walnut husk are been widely used in folk medicine. These vegetal materials have been reported as a source of bioactive molecules such as the phenolic compounds. In this research, there were analysed different quality parameters afferent to several walnut varieties, harvested from the germplasm collection located at S.C.D.P. Vâlcea, Romania. Romanian cultivars ‘Jupâneşti’, ‘Valrex’ and ‘Valmit’ and French one ‘Franquette’ were analyzed. The variation in bioactive compounds content from the walnut leaves and walnut husk at different developmental stages (from June to September) was investigated. The results showed that the content in polyphenols, flavonoids and tannins has significantly increased until the ripening stage, after that a decrease of the values of these parameters follows. Greater values of the three parameters were also observed at walnut leaves and green walnut husk of cultivars attacked by walnut blight, caused by the bacterium Xanthomonas arboricola pv. juglandis (Xaj). The findings of this study reveal the mode of variation in the content of polyphenols, flavonoids and tannins during the growing season of the walnut leaves and green walnut husk, emphasizing also the influence of Xaj. The results obtained demonstrated the potential of the walnut leaves and the green walnut husk as an economical source of antioxidant and antimicrobial agents.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 4, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

Walnut kernels are appreciated not only for their mineral content, vitamins, proteins, and valuable lipids, but also for the presence of polyphenolic compounds and biogenic amines. The temperature and storage time effects on some biochemical compounds from kernels collected from eight walnut genotypes grown at the Fruit Growing Research and Extension Station (SCDP) Valcea, Romania, were studied. In general, the phenolic and carotenoid compounds followed opposite trends during short-term storage and in some cases in medium-term storage. In both cases, there was a reduction in concentration during long-term storage, which was more pronounced for carotenoids. The most efficient method for preserving the walnut kernel’s phenolic content was freezing. Keeping the walnut kernel at room temperature assured the smallest carotenoid content decrease. Depending on the walnut cultivar, the preservation of the walnut kernel can be extended to five months by storage at −20 to −18 °C without loss of phenolic compounds, while a period shorter than five months (but certainly longer than three months) could be recommended for storage at 3–4 °C. Keeping it at room temperature can be an option for a short period (about three months). None of the preservation methods was adequate if the losses recorded for carotenoids were taken into account.

Hazelnut growing is becoming more and more important in the last years in Romania. Area harvested increased from 14 ha of hazelnut orchards in 2011 up to 634 ha in 2016 and the hazelnut in-shell production increased from 51 t to 602 t recorded in 2016 (FAOSTAT Database, 2018). There is a visible trend to plant at least several hundred hectares with this nut crop in the next years. For having better results, favorable areas for planting new orchards and adapted and good quality cultivars should be used. The most favorable areas for intensive hazelnut culture in Romania are those where the lowest temperatures in the winter do not drop below-20…-22°C, such areas can be found mainly in Oltenia, Muntenia, Dobrogea, Crişana, Maramureş and Banat regions, but there are also suitable micro-areas in the other regions of the country. In order to recommend a suitable cultivar assortment for the given ecological conditions, UCv-SCDP Vâlcea has evaluated over 60 foreign hazelnut cultivars and 9 Romanian ones during the last 20 years. Cultivars were evaluated depending the in-shell nut yield recorded at 5 by 3 m planting distances (667 plants/ha), precocity, adaptability to the environmental conditions, tolerance to diseases and pests, nut and kernel quality. Trials were organized under no-irrigation conditions in Râmnicu-Vâlcea area. The cultivars have been grouped function on their nut sizes in table varieties (nut weight over 3.0 grams and nut size index over 18 mm) and varieties for industry (nut weight below 3.0 grams and nut size index between 16 to 18 mm). The table cultivars that have been emphasized are: 'Ennis' (3.3 t/ha yield and nuts of 4.0 grams in average), 'Vâlcea 22' (3.0 t/ha yield and nut weight of 3.8 g), 'Cozia' (2.4 t/ha and nut weight of 3.8 g), 'Uriaşe de Vâlcea' (2.6 t/ha and nut weight of 4.0 g), 'Butler' (2.5 t/ha and nut weight of 3.8 g) 'Hall's Giant' (2.3 t/ha and nut weight of 3.8 g) and 'Fertile de Coutard' (2.1 t/ha and nut weight of 3.6 g). Among the cultivars for industry, the following had the best results in the given environmental conditions and suitable nut quality: ''T.G.D.L.'' (3.0 t/ha yield), 'Romavel' (3.0 t/ha), 'Arutela' (3.0 t/ha), 'Clark' (2.9 t/ha), 'Lewis' (2.7 t/ha), 'Primval' (2.3 t/ha) and 'Tonda di Giffoni' (2.1 t/ha). Data collected showed that fruit yield of the cultivars studied is determined in a proportion of 48.2% by the genotype while 16.2% is determined by the environment x genotype interaction. The phenological data emphasized that dichogamy degree varies from cultivar to cultivar. The assortment of cultivars that can be planted by the farmers depends on the adaptability to the environmental conditions and type of varieties, table or industry use. Ratio between cultivars to be planted in the farm varies on pollination schemes, market demands but also on the commercial capacity of the farmer to sell the hazelnut production. Cuvinte cheie: nucifere, Corylus avellana, alun.

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