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Tomatoes (Solanum lycopersicon L.) are one of the most important and most widely consumed vegetables in the world. The fruit contains considerable amount of different phytonutrients such as carotenoids, tocopherols, and vitamin C. In the present work, effects of some abiotic factors on the concentration of phytonutrients were investigated in tomato cultivated in two different types of soil. It was found that the type of soil had slight effect on the most important vital nutrients, while the ecological factors, particularly precipitation and average temperature 3 weeks before harvest, were of significant influence on such nutrients. It was found that low temperature and high precipitation before harvest caused the levels of carotenoids, tocopherol, and vitamin C to significantly increase by 65%, 46%, and 28%, respectively.

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Potato, Solanum tuberosum L. (2n = 4x = 48), is an autotetraploid species, the breeding of which at the tetraploid level is complicated by tetrasomic inheritance. Dihaploids (2n = 2x = 24) from the tetraploid cultivated potato have great potential for breeding and genetic studies. The common method deployed to obtain potato dihaploids is to make interspecific-interploidy (4x × 2x) crosses between a tetraploid seed parent and special clones from the diploid S. phureja as pollinator. Pollinators carrying a marker gene have been used, but unfortunately, these clones were very weak, with rare flowering and low male fertility under the given conditions. To find a suitable pollinator, three clones were selected from S. phureja based on flowering, pollen shed and male fertility and were crossed with five cultivated tetraploid potatoes to evaluate their dihaploid induction ability. A total of 1529 interploidy crosses were made, resulting in 1116 berries and 1456 seeds. The progeny were divided into two groups based on stem, flower and tuber colour: hybrids and non-hybrids (putative dihaploids). Chromosome counting in non-hybrid genotypes detected 39 dihaploids. The clone phu 3 and cv. Picasso, with 12.1 and 10.7 dihaploids per 100 berries, respectively, were the best dihaploid inducer and seed parent for dihaploid production.

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Cryopreservation appears to be a suitable solution for the maintenance of potato germplasms. The protocol described in this paper can be applied for the vitrification and preservation of meristems. During histo-cytological studies it is possible to observe modifications at the cellular level and to understand the adaptive mechanism to low temperatures. Control potato meristem tissue contained a number of meristematic cells with a gradient of differentiation. After freezing there were a large number of vacuolated cells, some of which exhibited broken cell walls and plasmolysis. The thickening of the cell wall, giving them a sinuous appearance, was observed after freezing and thawing the meristems, with ruptures of the cuticle and epidermal layer.

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The downside of plant tissue culture techniques is an unwanted microbial contamination. Elimination of contaminants is the first step of any successful investigation on plant tissue culture. Preliminary experiments on Araucaria excelsa R. Br. var. glauca (Norfolk-Island pine) (syn.: A. heterophylla) showed that most common decontaminants could not successfully eliminate the contamination. Therefore, nano silver (NS) colloids were evaluated for controlling contamination. Treatments were included soaking the explants in NS solution or adding NS to the culture medium. Explants were cultured on MS medium supplemented with appropriate growth regulators for their establishment. Results showed that surface sterilization followed by treatment with 200 mg l−1 of NS with soaking time of 180 min reduced the bacterial contamination from 61.5% to 11.3% and adding 400 mg l−1 NS to the medium reduced the bacterial contamination from 81.25% to 18.75%. Nano silver could be applied without adverse effects on plant growth and development. This is the first report on in vitro establishment of A. excelsa R. Br. using NS to reduce bacterial infections.

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The complete genome of Hosta Virus X (HVX), which is thought to be a distinct species of Potexvirus, was sequenced. Nucleotide sequences of HVX were compared with those of other members of the genus Potexvirus and phylogenetic tree was constructed. The range of identities of viral replicase open reading frame 1 (ORF1) between HVX and other potexviruses were 43.1%–55.1% and 35.9%–46.6% at the nucleotide and amino acid levels, respectively. Phylogenetic analysis was performed according to the amino acid sequence of the replicase to determine the position of HVX in the genus Potexvirus. Results from the phylogenetic analysis demonstrated that HVX was in the same group as Cassava common mosaic virus (CsCMV), Plantago asiatica mosaic virus (PlAMV), Tulip virus X (TVX), and Hydrangea ring spot virus (HdRSV). In particular, coat protein (CP) sequences among viruses from different Hosta cultivars were revealed to be less variable than those from different isolates of Potato virus X (PVX), a Potexvirus type species. In the present study, HVX was transmissible by seeds of the Hosta “Blue Cadet” cultivar. Moreover, HVX was detected in the embryo but not in the seed coat or endosperm of the seed.

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The quality of miniature potted roses during their shelf life is limited by bud abscission and premature flower senescence. Rosa hybrida L. cv. Amore plants were pretreated with silver thiosulphate (STS) at 0.2 and 0.4 mM and with 1-methylcyclopropene (1-MCP) at 0.3, 0.5 and 0.7 g m-3 for 6 h in order to investigate the effects of these chemicals on the postharvest quality. Both chemicals extended the flower longevity as well as the plant display life compared with the untreated control. The best treatments in this respect were STS at 0.4 mM and 1-MCP at 0.5 g-3 for 6 h, which resulted in the least degradation in the chlorophyll content of the leaves. The treatment with STS at 0.4 mM increased the flower longevity and plant display life by 1 and 1.67 days, respectively, compared with the 1-MCP pretreatment at 0.5 g m-3. Since 1-MCP treatment does not have the heavy metal implications of STS treatment, the use of 1-MCP pretreatment for extending the shelf life of miniature potted rose cv. Amore was recommended.

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Cover crops serve as an essential source of nutrients in the soil and generally improve the soil’s properties. Cover crops’ production is considered a benefit of the soil quality; by protecting the soil from erosion, reducing the weeds and the so-called soil-borne plant pathogens. Different varieties of cover crops can be cultivated such as legumes, non-legumes, brassica, and grass-type of plants with a variability of the symbiosis. A pot experiment was carried out with five cover crops, as non-symbiont (Brassica carinata B.c.), single-symbiont with arbuscular mycorrhiza fungi (AMF) (Phacelia tanacetifolia P.t., Avena strigosa A.s.) and double symbiont with AMF and nitrogen-fixing bacteria (Vicia benghalensis V.b., Vicia faba V.f.) crops; and a mixture of the five species, placed in sandy soil (arenosol) in plastic pots (5000 g soil) in 4 repetitions. One of the pots with mixed cover crops was inoculated by AM fungi industrial product. We measured soil biological activity of dehydrogenase (DHA) and fluorescein-diacetate (FDA) enzymes, the frequency of AM fungi (F%), the all protein, glomalin content and electrical conductivity (EC) of the soils. Mixture of all the cover crops resulted maximum EC and significantly enhanced the enzymatic, DHA, FDA activities in comparison with single plants. Mycorrhiza colonization frequency was high in all cover crops except the mustard (B.c.), as nonsymbiont. Vetch (V.b.), as double symbiont was responding very positively to AMF inoculation, and enhanced the performance of its growth. It was found in the pot experiment, that vetch, has the highest capacity to retain soil-protein, glomalin concentration, as well. The mixture of five cover crops could be suggested to use, due to the synergistic positive performance of the individual crops, and the better functioning of beneficial fungal / bacterial symbiosis.

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Medium chain fatty acids are candidates of partial sulphur dioxide replacement in wine, as a solution to the growing consumer concerns about chemical additives. In botrytised sweet wine specialties, large amount of sulphur dioxide addition is one of the effective practices to stop alcoholic fermentation. Increasing medium chain fatty acid levels up to 80 mg l-1 was tested as a sole inhibitor on solid agar surface. S. bacillaris seemed to be the most sensitive, S. cerevsisiae and S. bayanus were more tolerant, while Z. bailii showed the highest tolerance. Then, increasing medium chain fatty acid levels up to 40 mg l-1 combined with 100 mg l-1 sulphur dioxide was introduced into a Tokaj Essence under refermentation. After 56 days, the highest dosage had pronounced effect on the yeast population, but the refermentation was not inhibited completely. Medium chain fatty acids have varying inhibitory effect on botrytised wine-related yeasts, moreover, it could be used effectively in media with high ethanol content, unlike Tokaj Essence.

Open access

I. dentata root samples were collected in Oct. 2015 and identified by Dr. Sang-Won Lee, a senior researcher in National Institute of Horticultural and Herbal Science, Rural Development Administration (RDA), Korea. Whole I. dentata plants were

Open access