Infirm effect of phylogeny on morphometric features in a cryptic Gobio species complex

Several recent notes prove that taxonomic relations of close relative animal groups (species complexes or cryptic species) can be revealed by the combined use of genetic and morphologic methodologies. At the same time scarce information can be found about how phylogeny, population origin, and sexual dimorphism affect the morphometric features of these species. In our present work, we performed simultaneous phylogenetic and morphological studies on the taxonomically still questionable Carpathian stream dwelling gudgeons (Cyprinidae, Gobio) by using two different methodologies (distance based and geometric morphometry). Our results were in correspondence with the previous findings, showing the presence of three phylogenetically more or less distinct groups in the area. The results of the whole-body geometric and the traditional, distance-based morphometry reflected the extent of phylogenetic differences. While the results of geometric scale morphometry did not correspond with the genetic subdivisions. Results of three way PERMANOVA analyses showed that the phylogenetic effects on morphometry is less considerable as the population origin or the sexual dimorphism at these cyprinid taxa. Our investigation contributed to the better understanding of the taxonomy of fish stocks in the Carpathian Basin, and to their conservation, but additional investigations will be needed to clarify the exact taxonomic position of the gudgeons (’Gobio sp1’) dominating the eastern part of the studied drainage

Infirm effect of phylogeny on morphometric features in a cryptic Gobio species complex

Abstract Several recent notes prove that taxonomic relations of close relative animal groups (species complexes or cryptic species) can be revealed by the combined use of genetic and morphologic methodologies. At the same time scarce information can be found about how phylogeny, population origin, and sexual dimorphism affect the morphometric features of these species. In our present work, we performed simultaneous phylogenetic and morphological studies on the taxonomically still questionable Carpathian stream dwelling gudgeons (Cyprinidae, Gobio) by using two different methodologies (distance based and geometric morphometry). Our results were in correspondence with the previous findings, showing the presence of three phylogenetically more or less distinct groups in the area. The results of the whole-body geometric and the traditional, distance-based morphometry reflected the extent of phylogenetic differences. While the results of geometric scale morphometry did not correspond with the genetic subdivisions. Results of three way PERMANOVA analyses showed that the phylogenetic effects on morphometry is less considerable as the population origin or the sexual dimorphism at these cyprinid taxa. Our investigation contributed to the better understanding of the taxonomy of fish stocks in the Carpathian Basin, and to their conservation, but additional investigations will be needed to clarify the exact taxonomic position of the gudgeons (’Gobio sp1’) dominating the eastern part of the studied drainage.</jats:p

Variation of Soil Structure in the Foot and Toe Slopes of Mt. Vukan, East-central Serbia

This paper presents the variation of soil structure along the foot and toe slopes of Mt. Vukan, East-Central Serbia. The analysis of aggregate size distribution and structure indices were conducted by means of soil units, characteristic soil horizons and elevation differences along the study area. Soils of Great Field located at different elevations were found to have significant variation in ASD and soil structure indices. Topsoil horizon of Eutric Cambisols have higher MWD after dry sieving, but at the same time it has the highest variation in MWD after wet sieving, indicating low water stability, which is opposite to the coefficient of aggregability. We share an opinion that change in MWD better depicts soils structure stability to water. The results of correlation analysis indicated that clay content is correlated more to structure indices compared with SOM content. SOM is significantly correlated with ASD and soil structure indices only in Calcomelansols, whereas the significant correlation of clay content and soil structure is more evident in Eutric Cambisols and Non-calcaric Chernozems, compared with other soil units. Soil structure variation along the lowest chain of Catena might be strong, and that it has to be analyzed from the point of view of soil unit and their corresponding soil horizons

IMPACT OF GRAZING ON SOIL ORGANIC MATTER AND PHYSICAL PROPERTIES OF A FLUVISOL IN NORTWEST SERBIA

The effects of long-term (>20 yr) grazing on the selected physical properties of a non carbonated silty-clay Fluvisols were studied in the region of the Kolubara Valley, Northwest Serbia. Two adjacent land-use types (native deciduous forest and natural pasture soils converted from forests for more than 20 years) were chosen for the study. Disturbed and undisturbed soil samples were collected from three sites at each of the two different land-use types from the depths of 0–15, 15–30 and 30–45 cm. In relation to the soil under native forest, soil organic matter content, total porosity and air-filled porosity were significantly reduced after long-term of grazing. The bulk density (0.99–1.48 g cm–3) and the saturated hydraulic conductivity (6.9.10–2–3.2.10–4 cm s–1) were significantly lower in forest compared to the adjacent pasture (ex-forest) soil (1.49–1.55 g cm–3 and 3.4.10–4–5.5.10–4 cm s–1, respectively). In addition, forest had significantly lower dry mean weight diameter (7.0–9.2 mm) and greater wet mean weight diameter (2.0–2.6 mm) for 0–45 cm depth compared with the pasture (8.8–9.4 mm and 1.8–2.3 mm, respectively). The decrease of soil organic matter content and reduction in aggregate stability under long-term grazing rendered the soil more susceptible to compaction. In conclusion, the results of this study indicate that removal of permanent vegetation in the conversion process from forest areas to pasture land may lead to loss of soil productivity and serious soil degradation. Obviously, there is a need for greater attention to developing sustainable land use practices in management of these ecosystems to prevent further degradation of pasture soils in the region

ЕSTIMATION OF YIELD STABILITY OF ZP MAIZE HYBRIDS USING DIFFERENT STATISTICAL MODELS

Eight ZP maize hybrids, belonging to FAO 300-400 maturity groups, were tested during the 2018 year at six different environments in Serbia. All examined hybrids have been recently registered in Serbia. The aim of the study was to identify hybrids with the highest grain yield, as well as with high yield stability over different environments. The experiment was conducted according to Randomized Complete Block Design in three replications. For the estimation of yield stability, different statistical analyses were done: regression coefficient (bi), deviation from regression (S2 di), Shukla stability variance (ri2 ), and cultivar superiority measure (Pi). Maize hybrids ZP 4540 and ZP 4077 showed the highest yield potential, but they also had high moisture content in harvest. Hybrid ZP 4567 had above average yield and also high stability, while hybrid ZP 3536 had average yield, good stability and the lowest moisture content in the harvest. Although hybrid ZP 4540 obtained the highest grain yield in trial, it performed unstable according to the results of stability analysis. Based on the results obtained in the experiment, hybrids ZP 4567 and ZP 3536 are recommended for further testing in 2019 and initial commercializatio