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Citrus is grouped under the salt sensitive crops. Mycorrhizal fungi, a symbiotic relationship between plant roots and beneficial fungi, are supposed to impart the stress tolerance in the host plants. The stress tolerance improved due to Arbuscular Mycorrhizal fungi (AM fungi) colonization can be attributed to enhanced mineral nutrition. In the present study the efforts are made to evaluate the effectiveness of AM fungi with two citrus genotypes under salt stress. Three-month-old seedlings of Karna Khatta (Citrus Karna) and Troyer Citrange (Poncirus trifoliata × Citrus sinensis) were inoculated with the indigenous soil based AM inocula (mixed strains). The salinity gradient was developed by frequent irrigation with NaCl (0, 50, 100, 150 mM w/v). The results indicated that all the physical parameters were affected with increasing salinity. The proline accumulation increased while the chlorophyll, calcium and magnesium contents decreased significantly with increasing salinity. In general, the decreased AM colonization did not show any significant effects under salt stress.

Thymbra spicata var. spicata, which grows wildly in the flora of Turkey, is known as thyme. A field trial was conducted to determine suitable harvesting time and cutting height for Thymbra, therefore plants in the trial were harvested at two cutting heights in various stages of development in the course of the growing season (pre-flowering, full-flowering and post-flowering). It was determined that the time of harvesting had a significant effect on herbage yields, oil percentage and oil yield. The highest drug leaf yield (3.107 t/ha) was obtained in the full-flowering stage with 10 cm cutting length, essential oil percentage ranged from 1.58 to 2.33%, the highest essential oil yield (70.7 l/ha) was obtained at the full-flowering stage with 10 cm cutting length. As a result of this study, harvesting in the full-flowering stage with 10 cm cutting height was the best treatment in respect of the yield of dry matter and oil for thyme (Thymbra spicata) cultivation.

Two potato cultivars Kufri Bahar and Kufri Jyoti were stored in heaps and pits under ambient conditions of sub-tropical plains of northern India and their chipping quality was determined after 90 days of storage. During storage there was a significant reduction (33.84%) in the reducing sugar content of potatoes and improvement (31.63%) in chip colour. Sugar levels in stored potatoes were within the acceptable limit for processing and table purposes indicating that potatoes stored up to 90 days on the farm in heap and pits are suitable for these two purposes.

Nine identification RAPD markers (Moravcová et al. 2003) were used to distinguish 24 clones and grapevine cultivars. No polymorphism was detected among all the tested clones of Chardonnay, Pinot gris and Zweigeltrebe from Polešovice. Pinot noir, Pinot gris, Pinot blanc and Pinot Meunier were indistinguishable within clones, they also showed the identical RAPD profile within cultivars (except discussed sample No. 26). On the other hand, Auxerrois as a relative to cultivars of Pinot group showed unique patterns and may be classified as a different cultivar. Some irregularities within the cultivars of Pinot family from Oblekovice were also found, several of them gave different results from those expected: Pinot blanc sample 26 has the RAPD profile typical of Chardonnay. A new abnormal RAPD pattern as a marker of typical Chardonnay and Pinot profiles was observed in two cases. While RAPD banding patterns could not distinguish between the known clones, they were useful for distinguishing between phenotypically similar cultivars and for assessing the origins of cultivars thought to have originated as sports.

This study showed that rooting is strongly affected by natural leaf drop occurring during cutting collection. Observations carried out during sampling showed that cultivars with more than 80% leaf drop had lower rooting percentages than cuttings from cultivars with leaf drop between 44 to 75%, and that generally, the peaks of leaf drop coincide very closely with low rooting. Besides, it was found that there is a relation between Fe and N content in the bark of cuttings and their rooting. The peaks of Fe content coincide with the peaks of rooting. In contrast, the peaks of N content coincide with the lowest percentage of rooting. Overall, there seems to be no clear-cut relation between rooting and contents of P, K, Ca, Mg, Mn and Zn.

In greenhouse conditions a 3-year small-plot experiment was conducted on loamy Chernozem originating from the humus horizon to investigate the effect of sodium humate application on yield, nitrate content and vitamin C content in green pepper fruits. The application of 5 kg of sodium humate per hectare in the form of watering 3 weeks after planting of pepper seedlings under full NPK nutrition (N nutrition was divided as follows: 2/3 of total N before planting and 1/3 of total N together with sodium humate 3 weeks after planting) resulted in a statistically significant increase in pepper yield by 13.6% at a concomitant significant reduction of nitrate content in pepper fruits by 12% and increase in vitamin C content by 28.6%.

An assortment of 15 cultivars of root parsley was studied in field experiments to evaluate morphological characteristics, market yield, content of selected minerals and nitrate content. Storage ability of roots was also assessed. Mean root weight ranged from 87 g (cv. Bartowich Long) to 129 g (cv. Atika). Root head diameter was from 39 mm (cv. Lange) to 49 mm (cv. Halflange Omega and Hamburg). Mean root yield amounted to 1.35 kg/m² and the highest value was found in cv. Atika. Nitrate content did not exceed the tolerance limit ranging from 113 to 617 mg/kg of f.m. Mean content of K was 4,690 mg, Ca 124 mg, Mg 509 mg, and Na 425 mg/kg of f.m. Weight losses ranged from 10 to 32%; cv. Jadran showed the lowest value. Newer Czech cultivars (Atika, Jadran, Orbis) had a good commercial and growth potential.

Caraway fruits contain 1-6% of essential oils consisting of about 30 compounds, from which carvone and limonene account form the main portion, about 95%. To evaluate the quality of various caraway cultivars, the amounts of essential oils and the carvone/limonene ratio were measured. The most common method of essential oil evaluation is steam distillation in accordance with Standard ČSN 58 0110, but an alternative method - supercritical fluid extraction (SFE) - was also investigated in this paper. Ground caraway fruits were extracted under different SFE conditions (pressure, temperature, use of modifiers). Released compounds (carvone and limonene) were quantified by GC.

Leaf samples from 12 peach cultivars (Prunus persica [L.] Batsch.) (Early Crest, May Crest, Flavor Crest,Sun Crest, Fayette, Katherina, Loadel, Andross, Everts, May Grand, Firebrite and Fairlane) grafted on four peach root-stocks were analyzed for their nutrient content. The analysis of variance for leaf nutrient concentrations indicated very significant effects and interactions among cultivars and rootstocks. The rootstock effect on the absorption of nutrient elements was higher for Ca, K, P, Mg, N, and lower for Cu, Zn, Fe, Mn, and B. Generally cultivars grafted on GF 677 had higher N, K, Fe, Cu and lower Zn, Mn, and B, while leaves from cultivars grafted on wild seedlings were found to contain higher Mg and lower P, K, Fe concentrations. Leaf B and Ca were higher for cultivars grafted on Sant Julien GF 655/2, while cultivars on Damas GF 1869 had higher P, Zn, Mn and lower N, B, Ca, Cu concentrations. Leaf N was lower for Fayette on all four rootstocks and significantly different from all other cultivars. Leaf P was lower for Everts and higher for Katherina. Lower concentrations were observed in Early Crest for Fe and Zn, in Andross for Mn, and in Loadel for B, while Flavor Crest had higher concentrations of all these elements. Leaf Zn was the highest for Sun Crest on wild seedling and the lowest for Early Crest on the same rootstock. Similarly leaf N was the highest for Katherina on Damas and the lowest for Fayetteon the same rootstock. Also leaf Mg was the highest for Fayette on Damas and the lowest for Fairlane on Damas. Peach tree mortality was the highest for Damas 1869 and lowest for Sant Julien. Also tree mortality was highest for Early Crest and Sun Crest and lowest for May Grand, Firebrite, and Katherina. The observed trends in the leaf nutrient composition, as regards the cultivars, rootstocks and their interactions, emphasize the importance of these factors on a new peach orchard establishment and macro-microelement fertilization.

This four years experimentation work was aimed at research on using various waste organic materials and especially timber bark in cultivation substrates as a substitute of peat. Sixty-four special isolated cultivation beds were established for this purpose, each of 4.8 m³ volume, in which 11 variants of substrates consisting of different proportions of different components in several replications were tested. Standard substrates Horticultural substrate B and RKS I. were used as controls. Another variant was used as a control for growing tests of plants in containers. All tested substrates were enriched with hydroabsorbent TerraCottem. In some variants reserve fertilisers with slow release of nutrients (Silvamix Forte) were applied. For cultivation testing of studied substrates four ornamental tree species (Alnus glutinosa, Fraxinus excelsior, Salix alba, Salix matsudana) were chosen. The best evaluated variants were the ones containing 50 and 75% of bark in combination with sand. The worst was the variant composed of chips and sawdust. Thanks to the use of hydroabsorbents, even the variant containing 100% of sand appeared to be very good. The tested trees had different reactions to the different types of substrates depending on their species requirements. The limiting growth factor for Alnus was the content of water in the substrate. Similarly, the content of available nutrients in the substrate was essential for Fraxinus. The hardwood cuttings of Salix not only rooted into the substrate in a few weeks, but also formed aboveground parts of the required sizes. Obtained data on growth parameters differed according to the diversity of requirements of the different studied species.