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Arbuscular mycorrhizal (AM) fungi are obligatory biotrophic symbionts living in the roots of most terrestrial plants. AM fungi (AMF) have a positive effect on plant growth and plant nutrition, especially under stress conditions. The aim of the present study was to observe the relationship between the mycorrhizal dependency and nutrient uptake of host plants and the rate of AMF colonization in a pot experiment. The degree of host growth responses to AMF colonization is expressed as mycorrhizal dependency (MD). The pot trial was set up with a sterilized calcareous chernozem soil from Nagyhörcsök (Hungary) in a growth chamber under controlled climatic conditions. Tomato (Lycopersicon esculentum L.) plants were inoculated with Glomus claroideum (BEG23) , Glomus fasciculatum (BEG53), Glomus geosporum (BEG11), Glomus mosseae (BEG12) strains and a Glomus mosseae AMF culture produced by authors. The dry biomass production, the micro- and macronutrient concentrations of the shoots and the parameters of the mycorrhizal infection were determined. Each AM fungi species or isolate caused different and distinct changes in host plant growth and nutrient uptake. The biomass production of tomato increased significantly in the presence of AM symbiosis. The mean values of MD, calculated from shoot dry matter, varied between 36% and 55%. Mycorrhizal inoculation improved the P, N and K uptake of tomato. The highest values for root colonization, frequency of infection or arbuscular richness were found in the root of tomato inoculated with the two Glomus mosseae strains. The highest MD and nutrient contents appeared in the shoot of tomato treated withour Glomus mosseae strain, which may indicate a stronger affinity (compatibility) between the symbiotic partners. The results confirmed that the selected AMF strains are applicable in sustainable horticulture.
The aim of our study was to investigate the susceptibility of some Chenopodium species (Chenopodium album, C. glaucum, C. berlandieri, C. ugandae) to six viruses (Alfalfa mosaic virus, Cucumber mosaic virus, Obuda pepper virus, Potato virus Y, Sowbane mosaic virus, Zucchini yellow mosaic virus). Fourteen plants of each species were mechanically inoculated and virus susceptibility was evaluated on the basis of symptoms and back inoculation. A series of new host-virus relations were determined.
In this review results are summarized regarding the effect of virus infection on the physiological processes of weeds. Through several host-virus model relations the biomass and seed production, seed viability and germination, nutrient uptake, drought-resistance and photosynthetic pigment content of healthy and virus infected plants were compared. Because of their broad host range and high genetic variability viruses cannot be used for biological weed control. It was concluded that viruses unfavourably can influence physiological processes of weeds. Therefore, they may contribute indirectly to the reduction of competitive ability and population of weeds.
Abstract
Enzymatic hydrolysates of mechanically deboned meat (MDM) for a long time have been used as flavouring and functional food ingredients in the food industry and also as the bases of formula foods for special dietary uses.
The aim of the present study was to produce MDM hypo-antigenic products with improved digestibility and high biological value to be used as a milk protein alternative. turkey MDM was treated with digestive enzymes (trypsin and/or α-chymotrypsin, or pancreatin), followed by freeze drying. The optimised reaction conditions of hydrolysis were at 6% (w/v) of meat protein in 0.1% NaHCO3 buffer, pH 7.5; pancreatin enzyme with 50 TAME units/g meat protein substrate, 37 °C and 60 min). Hydrolysates (MDMH) were assessed for degree of hydrolyses (DH, %) by using trinitrobenzenesulphonic acid method and MW distribution by SDS-PAGE. Modification of immune reactive binding sites in MDMHs was monitored by immunoblot with cow’s milk, chicken egg or meat allergic human patients’ sera. Biological value indices (True Digestibility (TD), Net Protein Utilisation (NPU), Biological Value (BV)) were determined using rat feeding trials. Among the MDMH products, the pancreatic hydrolysate proved to be the most favourable in terms of biological value and digestibility as well as hypoallergenic property.
Nitrate accumulation in plants is a natural phenomenon resulting from uptake of nitrate ion in excess of its reduction and subsequent assimilation. The water soluble nitrate content of various carrot and red beet varieties was measured as a function of irrigation and mineral supplement in three years. In the first year, the nitrate content increased in both roots (significant differences were found for three carrot and at three red beet cultivars) following the irrigation. The activity of nitrate-reductase in the leaves was also significantly higher after irrigation in three red beet varieties in 1998. The mineral supplement in most of the carrot varieties increased the nitrate content. In the third year, the impact of water supply showed various tendencies in nitrate accumulation in both vegetables. On the basis of results for three years, the conclusion was that the seasonal and varietal differences were also remarkable.
The Mysteries of Mithras and Other Mystic Cults in the Roman World
Introduction. An Occasion to Deal with Mithraism Anew
Abstract
The use of the 99Mo
99mTc generator in nuclear medicine is well established world wide. The production of the 99Mo (T1/2 = 66 h) parent as a fission product of 235U is largely based on the use of reactor technology. From the early 1990's accelerator based production methods to provide either direct produced 99mTc or the parent 99Mo, were studied and suggested as potential alternatives to the reactor based production of 99Mo. A possible pathway for the charged particle production of 99mTc and 99Mo is irradiation of molybdenum metal with protons via the reaction 100Mo(p,2n)99mTc and 100Mo(p,pn)99Mo, respectively. The earlier published excitation functions show large differences in their maximum that result in large differences in the calculated yields. We therefore decided to study the excitation function for these proton-induced reactions. In this work the newly measured excitation functions as well as an evaluation of earlier measured data and a discussion of the observed disagreements are presented.
Potato (Solanum tuberosum L.) is the fourth most important food crop in the world. It is the most economically valuable and well-known member of the plant family Solanaceae. Potato is the host of many pathogens, including fungi, bacteria, Phytoplasmas, viruses, viroids and nematodes, which cause reductions in the quantity and quality of yield. Apart from the late blight fungus [Phytophthora infestans (Mont.) de Bary] viruses are the most important pathogens, with over 40 viruses and virus-like pathogens infecting cultivated potatoes in the field, among which Potato virus Y (PVY), Potato leaf roll virus (PLRV), Potato virus X (PVX), Potato virus A (PVA), Potato virus S (PVS) and Potato virus M (PVM) are some of the most important viruses in the world. In this review, their characteristics and types of resistance to them will be discussed.
