Fulltext search in archive

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.

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.