In this study the effect of different grassland managements (cattle grazing with different intensities and mowing) on soil mesofauna, i.e. mites (Acari) and springtails (Collembola), was studied. Mites and springtails are the most numerous representatives of soil mesofauna organisms living in the upper soil layers (up to 5 cm). Soil mesofauna groups or species are commonly used as bioindicators of soil health. The experiment was carried out from 2007 to 2009 in the West Sudety Mountains, Poland. Pastures and meadows were under organic farming management, without pesticides or synthetic fertilizers, and restricted livestock density. Soil samples were taken three times a year (in May−June, July and October) from pastures grazed at different frequencies: once, twice and four times a year, alternate management (grazed and mown pasture) and mown meadow. Mites were identified according to orders or suborders (Oribatida, Gamasida, Prostigmata, Astigmata), while springtails to the species level. The data were analysed using a general linear model (GLM). The mesofauna taxa in relation to the treatment and date were analysed with the canonical correspondence analysis (CCA). The data from three years showed that most soil mesofauna assemblages occurred in significantly higher numbers on the pasture grazed once or twice and on alternate managed pasture than in pasture grazed four times a year and mown meadow. The CCA analysis showed the preference of most springtail species to pasture grazed once a year, while mites preferred pasture grazed twice a year and alternate management. The number of species and the abundance of the most numerous species (Protaphorura pannonica, Desoria multisetis and Folsomides parvulus) did not differ significantly between treatments. To summarize, cattle grazing once or twice a season or alternate management (grazing and mowing once a season) have a positive impact on soil mesofauna.
Stem base health of spring barley cultivated under organic, integrated and conventional systems and fungal communities were studied. A worst plant health status was observed in the organic system. The macroscopic and subsequent mycological analyses revealed the occurrence of Bipolaris sorokiniana and Fusarium spp. The incidence of B. sorokiniana on stem bases was clearly dependent on a farming system, and the highest incidence of this pathogen was observed in the organic system. Also, in that system, Fusarium spp. were isolated more numerously in the beginning of tillering, but in dough stage B. sorokiniana was the most prevalent pathogen, and Fusarium spp. were more numerous in integrated and conventional systems. It is worth to note that organic conditions could be favourable to Gliocladium spp. Because of growing interest in ecology, excluding the use of pesticides and increasing popularity of biological disease control, these antagonistic fungi could be useful in organic systems.
Tetranychus urticae (Acari: Tetranychidae) infesting many plants but Mentha viridis L., and Mentha piperita L., were low in number of infestation. Therefore the objective of this study was to identify the resistance of M. viridis and M. piperita plants against T. urticae by studying the external shape and internal contents of those plants. For morphological studies, dried leaves were covered with gold utilizing an Edwards Scan coat six sputter-coater. For histological studies, arrangements of Soft Tissue technique were used. For phytochemical studies, the plants were cut, dried and then high performance liquid chromatography (HPLC) was used. While feeding the mites were collected from the area between oily glands, trichomes and respiratory stomata in both mint species. The most important leaf structures in aromatic plants are the oily glands found on the external part of the leaves (both upper and lower epidermis). The number of oil glands in M. viridis leaves was greater than in M. piperita; the trichomes on the epidermis of M. viridis were greater in number than in M. piperita; the spongy mesophyll in M. viridis was much thicker than in M. piperita. The essential oils in the leaves of both mint species contained 71 compounds representing 99.61% of the total oil constituents identified from M. viridis before infestation, and 90.95% after infestation, and about 99.65% from M. piperita before infestation, and 99.98% after infestation.