Cross-(in)compatibility in apricot (Prunus armeniaca L.)

Summary

Eight apricot (Prunus armeniaca L.) cultivars and selections were self- and cross-pollinated in order to determine their pollen and stylar compatibility. Overall, 40 pollination combinations were examined. Pollen-tube growth in pistils pollinated in the laboratory was analysed using fluorescence microscopy. Three inter-incompatiblity groups of cultivars were found, of which two had not been described previously, while an existing group was expanded with one additional cultivar. The first group consisted of three Hungarian cultivars (‘Ligeti Orias’, ‘Cegledi Orias’, and ‘Szegedi Mammut’) and a Moldavian cultivar (‘Kostjuzhenskyi’). The second group consisted of two American cultivars (‘Stark Early Orange’ and ‘Nugget’). The third group consisted of two Serbian selections (‘Novi Sad Early’ and ‘Frushka Gora Early’). In the incompatible cultivar combinations, pollen-tube growth stopped in the style with the formation of the characteristic swelling. In the compatible combinations, the pollen tubes reached the ovary in the majority of the pistils examined.     

Epidemiological and microbiological study of an outbreak of infectious keratoconjunctivitis in sheep

After several thousand sheep had been imported from Australia and New Zealand to Croatia during 1995, many native sheep that had been in contact with the imported animals acquired a severe ocular disease closely resembling infectious keratoconjunctivitis. In affected flocks glucose-fermenting mycoplasma were isolated from 48 per cent of conjunctival swabs and Branhamella ovis from 58 per cent. Twelve of 42 culturally and biochemically identical isolates were identified as Mycoplasma conjunctivae by polymerase chain reaction. From the conjunctivae of two animals M conjunctivae and M arginini were isolated in mixed culture. For many reasons most farmers removed the imported animals from their flocks and only sporadic cases of the disease were recognised in 1996. At the end of 1997, six flocks which were clinically free of the disease but had been affected during 1995, and five flocks with no history of the severe ocular disease were examined clinically and microbiologically, and were found to be free of M conjunctivae infection. At the time, B ovis was cultured almost exclusively from sheep originating from flocks which had been affected during 1995 and/or 1996. It was usually isolated in pure culture or as the predominant bacterial species, and was often accompanied by mild conjunctivitis. There were no microbiologically confirmed new cases of infectious keratoconjunctivitis during 1998 and 1999.     

Levamisole synergizes experimental F4ac+ Escherichia coli oral vaccine in stimulating ileal Peyer's patch T cells in weaned pigs

Recent findings demonstrate that priming by levamisole of weaned pigs experimentally vaccinated against postweaning colibacillosis (PWC) contributes to immune protection from challenge-induced clinical disease through stimulation of the mesenteric lymph node cells that participate in cell-mediated immunity. With the objective of better understanding the mechanisms by which levamisole induces protective mucosal cell-mediated immune response to vaccination against PWC, it was tested whether the drug synergizes experimental F4ac+ Escherichia coli oral vaccine in stimulating T cells also in the jejunal lamina propria (JLP) and ileal Peyer's patch (IPP) upon virulent challenge. Commercial crossbred pigs weaned at 4 weeks were allocated into two equal groups. The experimental group was i.m. primed with levamisole at an immunostimulatory dose of 2.5 mg/kg once daily, for 3 consecutive days, and controls received saline. Both groups were vaccinated orally with the vaccinal E. coli strain on day 0 and challenged with the virulent E. coli strain 7 days later. All pigs were killed on postchallenge day 6. The results determined by immunophenotyping of isolated cells indicate that priming by levamisole of the vaccinated weaned pigs selectively recruited and activated T cells in the IPP, a lymphoid organ-generating B lymphocytes. The pig IPP is normally populated with up to 5% of CD3+ T cells and CD6 is an activation antigen expressed exclusively by T cells in swine. Therefore, a significantly higher number of CD3+ (P < 0.01) and CD6+ (P < 0.001) cells observed within the IPP follicles of the primed-vaccinated vs. unprimed-vaccinated challenge-infected pigs suggest enhanced T cell-mediated immunity in this B-cell compartment induced by the potentiating action of the drug and vaccine. The ability of levamisole to influence interaction between activated T cells and B cells in the IPP of primed-vaccinated weaned pigs, and the possibility that this interaction plays a role in regulating B-cell maturation within the IPP follicles, are discussed.     

Survival of spray‐dried and free‐cells of potential probiotic Lactobacillus plantarum 564 in soft goat cheese

A high viability of probiotics in food product, with a living cells threshold of 10⁷/cfu/g (colony‐forming units/g) is a challenge to achieve in food production. Spray drying is an efficient and economic industrial method for probiotic bacterial preservation and its application in food products. In this study, the survival of free and spray‐dried cells of potential probiotic strain Lactobacillus plantarum 564 after production and during 8 weeks of storage of soft acid coagulated goat cheese was investigated, as well as compositional and sensory quality of cheese. Total bacterial count of spray‐dried Lb. plantarum 564 cells were maintained at the high level of 8.82 log/cfu/g in cheese after 8 weeks of storage, while free‐cell number decreased to 6.9 log/cfu/g. However, the chemical composition, pH values and sensory evaluation between control cheese (C1 sample made with commercial starter culture) and treated cheese samples (C2 and C3, made with the same starter, with the addition of free and spray‐dried Lb. plantarum 564 cells, respectively) did not significantly differ. High viability of potential probiotic bacteria and acceptable sensory properties indicate that spray‐dried Lb. plantarum 564 strain could be successfully used in the production of soft acid coagulated goat cheeses.     

The Use of Multi Criteria Models for Decision Support System in Fruit Production

The success or failure of an investment project in fruit production also depends on the selection of the fruit species and variety. When selecting the variety for the creation of a new orchard it is necessary to perform the synthesis of different data and to look at all aspects of the investment. This paper presents the application of DEX multi-criteria decision making. The model was applied on 7 varieties of plum from the western Balkans region that were assessed by experts from “The association of agricultural economists of Western Balkans” using the Delphi method.By applying this model it has been shown that the ’Stanley’ is the most suitable for starting a new orchard while the varieties ’?a?anska ljepotica’ and ’?a?anska rodna’ are also very suitable for starting new fruit orchards and they have also received the value attribute “very acceptable”.Using this model all strong and weak sides of the observed plum variety were shown. For the final selection it is necessary to conduct research at a specific micro location where all characteristics of that area would also be taken into consideration.