Insecticidal activity and phytochemical analysis of Pyrus communis L. extracts against malarial vector, Anopheles pharoensis Theobald, 1901 (Diptera: Culicidae)

We aimed at investigating the insecticidal activity of Pyrus communis L. against the malarial vector, Anopheles pharoensis Theobald, 1901 and its phytochemical constituents. Leaves were collected and the crude extracts were prepared using hexane (PCH) and methanol (PCM). Tested PCH and PCM possess larvicidal activity against A. pharoensis with LC50 and LC90 values of 179.9, 41.2 and 314.1, 68.9 ppm, respectively. A significant reduction in the number of eggs laid by females A. pharoensis that developed from larvae treated with PCH and PCM was noticed. Also, PCH treatment showed highest repellent activity compared with PCM. GC/MS analysis of the PCH revealed the presence of 55 identified compounds subdivided into 2 major classes viz. phenyl alkanes (38.65 %) and oxygenated sesquiterpenoids (36.41 %). LC/MS of PCM had led to the identification of 37 compounds, mainly flavonoids, chalcones, phenolic acids and tannins. The results demonstrate the insecticidal potential of leaves methanol and hexane extracts from P. communis as green insecticidal agents for the control of malarial vector, A. pharoensis.

Expansion of tree and shrub plant species into undisturbed steppe phytocenoses

The article is devoted to the study of tree and shrub plant species that spontaneously invasively colonize anthropogenically undisturbed steppe ecosystems. The species composition, number and biometric characteristics of tree and shrub plant species are determined. It was established that there are 22 species, among which 8 show the greatest invasive activity, in 6 studied natural beams. These are: Cotinus coggygria Scop., Crataegus fallacina L., Prunus divaricata Ledeb., Prunus stepposa Kotov, Pyrus communis L., Rhamnus cathartica L., Robinia pseudoacacia L., Ros corymbifera Borkh. According to the Serensen index of species composition of tree and shrub plants, comparing the slopes of beams of different exposures, it was found that steppe tracts have different similarities between the slopes, but the highest figure was observed for Balka Demurynа (80%).

Aloe-Based Edible Coating to Maintain Quality of Fresh-Cut Italian Pears (Pyrus communis L.) during Cold Storage

Pear fruits are known for their antioxidant and nutritional characteristics. However, they are very susceptible to rapid decay. Edible coating (EC) represents a good strategy to maintain postharvest quality. The effects of two EC in slowing down the senescence processes in fresh-cut ‘Coscia’ pears were investigated: EC1 (A. vera gel, hydroxypropyl-methylcellulose and pomegranate seeds oil (PSO), EC2 (A. vera gel and hydroxypropyl-methylcellulose). Weight loss, firmness and colour decrease more slowly in both EC-treated than in untreated (CTR) slices; soluble solid content increases faster in CTR, indicating a faster ripening process. The specific investigation of undesired microorganisms did not generate any colony in all analysed samples. Sensory analysis confirmed that the tasters preferred the EC2-treated samples, as they were the only ones that did not show undesirable flavours until the last day of storage.

BIODIVERSITY OF FRUIT-BEARING FOREST SPECIES IN THE PROTECTED LANDSCAPE "KONJUH"

UDK: 634.2:574.4]:502(497.6 “Konjuh“) The area of the protected landscape "Konjuh" is distinguished by quality forest ecosystems, featuring diverse fruit-bearing forest species, which contributes to the conservation of biodiversity of the protected landscape "Konjuh". The aim of the paper is to assess the state of biodiversity of fruit-bearing species in the forest ecosystems of the study area, with the emphasis on determining the genus richness as a basis for conservation (in/ex situ), breeding and economic use. During the vegetation season in 2015 and 2016, several relevés (phytosociological plot) were made in the Protected Landscape "Konjuh". The results of the research indicate the high level of variability for most of the species according to characteristics of biology, pomology, and ecology. The fruit trees, like the noble hardwood, are wild cherry, (Prunus avium L.), wild pear (Pyrus communis L.), wild apples (Malus sylvestris Mill.), Breccia (Torminalis clusii M. Roem.), Sorbus aria L. et all, Wild cherry, Vrapcarka (Prunus avium L.) is the most famous forest fruit grower, occurs as a single tree or in smaller groups (Noćajević, 2009). The benefits of fruit-bearing forest species are emphasized in the bloom and the fruiting time, when "decorated" forest provide a rich bee pasture and feeding nutriment for forest fauna (Orešković et al. 2006). Fruit-bearing Forest species are significant as the genera of the varieties and as a basis for the grafting for high-grade varieties. Also, they are important for humans from the aspect of ecology, nutrition, dietotherapy, pharmacology and bioenergy balance.