Variability, heritability and correlations of some factors affecting productivity in peach

Factors affecting productivity in peach, such as flower density, initial and final fruit set by open pollination, and yield per m length of shoot were studied in 40 cultivars during a three-year period. Significant differences among cultivars were found for all studied properties. The coefficients of variability were the lowest for initial fruit set and then for final fruit set and flower density; while they were the highest for yield. The relatively high values of heritability were found for flower density and yield. Significant correlation coefficients were found between initial and final fruit set, flower density and yield, as well as between final fruit set and yield. In areas with a higher risk of freeze damage the cultivars characterized by higher flower density and fruit set should be grown because they can provide more consistent yield potential. At the same time, these cultivars require more intensive pruning and fruit thinning to achieve quality fruit

Testing of self-(in)compatibility in apricot cultivars from European breeding programmes

Self-(in)compatibility was tested in 40 new apricot cultivars from European breeding programmes Pollen-tube growth in pistils from laboratory pollinations was analysed using the fluorescence microscopy. Cultivars were considered self-compatible if at least one pollen tube reached the ovary in the majority of pistils. Cultivars were considered self-incompatible if the growth of pollen tubes in the style stopped along with formation of characteristic swellings. Of the examined cultivars, 18 were self-compatible and 22 were self-incompatible. Fluorescence microscopy provides a relatively rapid and reliable method to determine self-incompatibility in apricot cultivars

Isoenzyme polymorphism of almond genotypes selected in the region of northern Serbia

Isoenzyme polymorphism was studied in 20 almond (Prunus dulcis [Mill.] D. A. Webb) genotypes selected from seedling populations of unknown almond cultivars in the region of northern Serbia (Vojvodina). Fourteen enzyme systems were studied using the method of vertical polyacrylamide gel electrophoresis. Ten systems were polymorphic in twelve loci. This polymorphism allowed unique identification of all studied genotypes. The most useful enzyme for analysis of almond genetic variability was menadione reductase. Polymorphism identified for alkaline phosphatase, formate dehydrogenase, glutamate dehydrogenase, malic enzyme, and menadione reductase was reported for the first time in almond. Cluster analysis was used to construct a dendrogram on which five clusters with different number of genotypes could be identified

Relishes: The new pickled vegetables

There have been an increasing interest of consumers for a ide variety of pickled vegetable products worldwide. Regarding the regional vegetable supplies and relatively poor assortment of ready-to-use products, the need to broaden the offer of domestic pickled vegetables at the market came out. In this work recipes for different vegetables, spices and condiments were developed. The best graded samples were analyzed for their main chemical composition (dry matter, proteins, oils and fats, total acidity, total sugars, sucrose, starch, cellulose, pH) and energy- values

Morphological characteristics and germination of pollen in European and Japanese plum cultivars

In six cultivars of European plum (Prunus domestica L.) and six cultivars of Japanese plum (Prunus salicina Lindl.), pollen morphological characteristics: length (L), width (W), length to width (L/W) ratio, and percentage of pollen grains of normal size and shape, small size, and irregular shape were examined using scanning electron microscopy. In addition, pollen germination in vitro was studied using the agar plate method in a medium containing 15% sucrose. It was found that European plum cultivars have larger pollen grains (53.4 μm in length and 28.3 μm in width on average) compared to Japanese plum cultivars (length and width of 41.0 μm and 22.9 μm, respectively). Besides, European plum cultivars had more elongated pollen grains (L/W ratio of 1.88) compared to Japanese plum cultivars (L/W ratio of 1.79). The percentage of pollen grains of normal size and shape was higher in European plum cultivars (69.3%), compared to Japanese plums (51.9%). Similarly, pollen germination in vitro was significantly higher in European plum cultivars (66.2%) compared to Japanese plums (35.6%). A significant correlation was established between the percentage of pollen grains of normal size and shape and pollen germination in vitro (Pearson's correlation coefficients of 0.896 and 0.822 for European and Japanese plums, respectively)

Scanning electron microscopy analysis of apricot pollen grains

Morphology and ultrastructure of pollen grains were studied in nine apricot cultivars using scanning electron microscopy (SEM) technique. The following characteristics were examined in dried pollen grains: Length of polar axis (P), length of equatorial axis (E), P/E ratio, length of the colpus, width of the mesocolpium, and exine characteristics (number of ridges 100 μm-2 area, width of a ridge, and width of a furrow). All studied cultivars had isopolar, radially symmetric and tricolpate pollen grains, which had been classified as large in size. Length of polar axis ranged from 55.6 μm in 'Hungarian Best' to 59.5 μm in 'Goldrich', and length of equatorial axis from 27.0 μm in 'Sylred' to 30.5 μm in 'Goldrich'. Pollen shape was identified as prolate in six cultivars, and as perpolate in three cultivars. Colpus length and mesocolpium diameter varied in a range of 48.4-55.6 and 14.5-18.4 μm, respectively. All studied cultivars had striate exine ornamentation. Number of ridges 100 μm-2 of the exine surface was the lowest in cultivar 'NS-4' (21.3), and the largest in cultivar 'Laycot' (29.7). Ridge and furrow width varied in a range of 0.28-0.35 and 0.24-0.32 μm, respectively. SEM examination indicated that some pollen morphological characteristics such as size, shape, and exine ornamentation can potentially be used in the identification of apricot cultivars

Pollen morphology of some sweet cherry cultivars observed by scanning electron microscopy

Morphology and ultrastructure of pollen grains were studied in five sweet cherry cultivars lapins, 'Sunburst, 'Stella' and Wan') in two years using scanning electron microscopy (SEM). All studied cultivars had isopolar, radially symmetric and tricolpate pollen grains. Length and width of pollen grains were the highest in 'Sunburst' (50.1 and 25.7 mu m, respectively) and the lowest in 'Bing' (47.4 and 24.1 mu m, respectively). Pollen shape in all the studied cultivars was identified as prolate. Colpus length and mesocolpium width varied in a range of 40.5-44.9 and 14.4-16.3 gm, respectively. All studied cultivars had striate exine ornamentation. Number of ridges 100 mu m(-2) of the exine surface was significantly higher in 'Bing' (30.4) compared to those in other tested cultivars. Ridge and furrow width varied in a range of 0.28-0.35 and 0.26-0.30 mu m, respectively. Pollen grains examination by SEM indicated that several morphological parameters (size and exine characteristics) can be used to distinguish sweet cherry cultivars

The effect of temperature on pollen germination and pollen tube growth in vitro of sweet cherry cultivars

Temperature is one of the most important environmental factors that affect pollen performance during the reproductive phase of plant species. The study was carried out to determine the effect of three different temperatures (5, 15 and 25 degrees C) on the pollen germination and pollen tube growth in vitro of five sweet cherry cultivars: 'Bing', 'Lapins', 'Stella', 'Sunburst', and 'Van' and to detect possible differences in genotypic response. Temperature significantly affected pollen germination of all studied cultivars. High germination rates (66-75%) were obtained at 15 and 25 degrees C. However, satisfactory germination rates (around 50%) were also obtained at 5 degrees C in 'Lapins', 'Van' and 'Sunburst'. The influence of temperature was more prominent on the pollen tube growth. The length of pollen tubes was three to five times higher at 15 and 25 degrees C in comparison with 5 degrees C. This has led to the conclusion that the temperature of 5 degrees C, although it could be high enough for pollen germination, is not high enough for optimal pollen tube growth. The obtained results indicate differential cultivar response to the temperature during the pollination period. Better adaptation of some cultivars to low temperatures during the flowering could be an indicator of their wider geographical adaptation