Within the framework of the paper, the elements of supply chain of grain products were identified and analyzed in terms of structure. The assessment of the efficiency of grain processing enterprises, which are the integrator of the chain, using the SFA method (Stochastic Frontier Approach) was carried out. The supply chain integration degree, showing the strength of relationships of individual enterprises with business partners, was identified.
The level of damage to the cell membranes is a sign of aging of the seeds and a decrease in their viability. Conductometric seed testing method indirectly utilizes uncontrolled leakage of ions from seeds with damaged cell membranes to assess their viability. This involves the use of an electrical conductivity of the aqueous solution, in which seeds are soaked. The research was conducted in the years 2011−2014 and aimed at developing the methodology of evaluation of Scots pine and Douglas fir seeds by conductivity test. The aim of the study was to determine the relationship between electrolyte leakage and germination capacity of Scots pine and Douglas fir seeds. 402 samples of Scots pine seed and 90 specimens of Douglas fir seed from all over Poland were tested. The research material was both freshly harvested and stored. Scots pine seeds were obtained in the years 2008−2014, while Douglas fir – 2003−2013 as well as ones stored in the refrigerator for 15 years. Conductivity test and standard seed germination procedure of the analyzed species were used. For both Scots pine and Douglas fir, we noted that, as the electrolyte leakage rate increased, the germination capacity of the seed decreased. So we decided to test whether the vitality of the seeds was determined by means of a conductivity test. The best−fit regression model was determined and the mean expected germination capacity in the viability classes was calculated. 95% confidence intervals for the regression function were also determined. Evaluation of the viability of the seeds by means of the conductometric method is especially useful for seeds requiring a long stratification period (e.g. Douglas fir to determine the potential loss of their vitality. Although the ISTA seed evaluation rules do not require conductivity test for evaluating the seeds of Scots pine and Douglas fir, it may be applicable in situations where it is necessary to perform a rapid assessment of viability before spring sowing.
The objective of the study was to determine whether differences exist between the selected characteristics of Norway spruce cones and seeds depending on their location in the crown. The study was performed in two spruce tree stands growing under mountainous conditions (the Beskidy Mountains, southern Poland). In winter 2015, the cones were collected from 60 standing trees located in the two selected seed stands – Ujsoły and Rycerka. From each tree, the cones were collected from three crown zones: top, central and bottom differing in terms of light conditions. Two characteristics of the cones and six characteristics of the seeds were analysed. To determine quantitative and qualitative traits of seeds standard methods for seed testing were applied. Significant differences between the populations were determined for cone weight and fraction of full seeds, weight of 1000 seeds and germination capacity. The crown zones differed significantly in terms of fraction of cones in the parts of the crown and mass of one cone as well as weight of 1000 seeds, germination energy and germination capacity. Moreover, a significant intra−population variation was observed for a majority of the analysed characteristics (fraction of full seeds, weight of one cone, weight of 1000 seeds, germination energy, and germination capacity). However, no statistically significant interaction between population and crown zone was observed. A significantly lower contribution of cones in the bottom zone of the crown may affect the economic viability of the commercial harvest. On the other hand some of the important seeds traits (e.g. weight of 1000 seeds, germination energy and germination capacity) were significantly better in the bottom and central part of the crown than in the top zone. There are no justified circumstances (both qualitative and quantitative) to perform the cone harvest only from the top zone of the crown.
Within the framework of work on the anatomical structure and durability features of wood, as well as analyses of radial growth, a preliminary analysis was carried out in regard to variation in the heartwood within Black locust trees. The research was carried out in three stands of straight-stemmed trees in western Poland. The variation displayed by the heartwood around its circumference and the eccentricity of the trunks was characterised with reference to: the heartwood radial index (HRI), the cross-sectional shape factor for heartwood (CSsf) and the pith eccentricity index (PEcc). The results confirmed a relationship between the degree of variation around the circumference of the heartwood and the mean age of the stands, while at the same time making clear the high level of differentiation in radial variation at the level of the individual tree. The findings suggest that the fertility of the habitat does not exert much of an influence on the generation of heartwood in Black locust trees. No statistically significant relationship was obtained when the circumferential variation of the heartwood was set against the total height or diameter at breast-height. Only in the case of crown length, and then only at the Wołów site, was there a moderate negative correlation with the coefficients of circumferential variation.
The black locust (Robinia pseudoacacia L.) has been present in Poland for more than 200 years now, its range coming to encompass the entire country, albeit with a particular concentration of occurrence in the west. Overall, it is present in 3.4% of the stands making up Poland’s “State Forests National Forest Holding” (Państwowe Gospodarstwo Leśne Lasy Państwowe), and is the dominant species in 0.1% of stands. Thanks to its producing durable wood of favourable energetic properties, this species is used in medium-rotation (≤ 40-year) plantations as well as in biomass energy plantations (where there is a 5–7-year rotation). In terms of its nectar production, the black locust is second only to lime as the Polish tree best serving the production of honey. While the species shows marked expansiveness in Poland, it has not thus far been placed on the list of aliens capable of threatening native species or natural habitats. Breeding of the species has been engaged in – if to only a limited extent – in Poland for some 20 years now, and 2 selected seed stands have been registered, as well as 34 plus trees and 2 seed orchards.