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1.
Plants ofRuscus hypoglossum L. were grown in containers with perlite, an inert medium, or with soil, under similar-to-commercial conditions, for three winter seasons. Constant fertilization with soluble calcium [Ca(NO3)2] through the root zone resulted in a reduction of up to 78% in postharvest rot caused by artificial inoculation withBotrytis cinerea Pers. ex Fr. Control plants were treated by fertilization with N,P,K and all other elements, identical to the fertilizer containing calcium. Foliar application of Ca(NO3)2 to ruscus bushes or application of this compound or of CaCl2 or CaSO4 to mature cut branches standing in water, resulted also in a significant reduction in postharvest phylloclade rot. Application of CaSO4 and Ca(H2PO4)2 + CaSO4 to ruscus plants, from fertilizers containing 22% Ca and releasing the cation gradually, effectively reduced the susceptibility of cut branches to infection byB. cinerea.  相似文献   
2.
Peanut pod wart, a relatively new disease to peanut culture, was first reported in Israel in 1988 attacking peanut plants and causing dark warts on the pod. The causal agents are variousStreptomyces spp. Scanning electron microscopy showed a significant difference between healthy and diseased tissues of the exocarp and mesocarp layers of the pod; there were no effects on the endocarp layer. The mesocarp cells of infected tissue were smaller and more compressed than those of healthy tissue. In most cases two cells under the peak of the wart were extremely large and the cells growing from them toward the surface were uneven, forming the shape of a fan. The pathogen could be isolated from the soil and rhizosphere, but in the pod it was found only in the waited tissue. The microorganisms isolated from the warts belong to different groups ofStreptomyces spp.; subsequent pathogenicity tests proved their virulence to a limited host range. In potato, these isolates ofStreptomyces spp. caused deep pitted scab; in peanuts they caused warts. Peanut seeds which developed in infected pods were free of the pathogen if the shell was undamaged. However, the pathogen is surface seedborne, and contaminated seeds during the mechanical cracking process.  相似文献   
3.
The most serious symptom of Botrytis cinerea in tomatoes grown in greenhouses is stem rotting. Lesions on the stem may result from direct infection or from progression of the rot along infected leaves, until infection approaches the stem. In a set of experiments conducted in commercial greenhouses, an experimental greenhouse and growth chambers, the significance of the two types of stem infections was studied. In non-heated greenhouses most of the stem lesions originated from progression of the pathogen along infected petioles. The rate at which B. cinerea had progressed on infected petioles was 0.3–0.5 cm/day, an average of ca. 6 weeks was needed for a leaf infection to approach the stem. Application of Trichoderma harzianum T39 extended this time by 1–2 weeks and application of chemical fungicides by 3 weeks. Influence of the environment on the progression of B. cinerea along infected petioles was then determined. Within range of 5–30 °C, the higher the temperature, the more rapid was the rate of disease progression. The fungus progressed more rapidly on tomato petioles incubated at high vapour pressure deficit (VPD) rather than at low VPD. The source-sink relationship of the plant governed the rate of B. cinerea progression along the petioles as well: it was more rapid when the source was restricted (by shading) and slower when the sink was restricted (by removal of flowers and small fruits). The possibility that sanitation of infected leaflets would reduce the incidence of stem rotting was examined in two experiments. In plots not treated with a fungicide, the sanitation treatment substantially decreased the incidence of stem lesions and this treatment was as effective as weekly application of chemical fungicides.  相似文献   
4.
Figure 1 of the paper " Long-term activity in small aquatic animals" by A. A. Heusner and J. T. Enright (28 Oct. 1966, p. 532) is ambiguous to the extent that the two negative terminals might be interpreted as a common point in the circuit. In fact, these two points must be kept separate for the proper operation of the instrument.  相似文献   
5.
Trichoderma isolates are known for their ability to control plant pathogens. It has been shown that various isolates of Trichoderma, including T. harzianum isolate T-39 from the commercial biological control product TRICHODEX, were effective in controlling anthracnose (Colletotrichum acutatum) and grey mould (Botrytis cinerea) in strawberry, under controlled and greenhouse conditions. Three selected Trichoderma strains, namely T-39, T-161 and T-166, were evaluated in large-scale experiments using different timing application and dosage rates for reduction of strawberry anthracnose and grey mould. All possible combinations of single, double or triple mixtures of Trichoderma strains, applied at 0.4% and 0.8% concentrations, and at 7 or 10 day intervals, resulted in reduction of anthracnose severity; the higher concentration (0.8%) was superior in control whether used with single isolates or as a result of combined application of two isolates, each at 0.4%. Only a few treatments resulted in significant control of grey mould. Isolates T-39 applied at 0.4% at 2 day intervals, T-166 at 0.4%, or T-161 combined with T-39 at 0.4% were as effective as the chemical fungicide fenhexamide. The survival dynamics of populations of the Trichoderma isolates (T-39, T-105, T-161 and T-166) applied separately was determined by dilution plating and isolates in the mixtures calculated according to the polymerase chain reaction (PCR) using repeat motif primers. The biocontrol isolates were identified to the respective species T. harzianum (T-39), T. hamatum (T-105), T. atroviride (T-161) and T. longibrachiatum (T-166), according to internal transcribed spacer sequence analysis.  相似文献   
6.
Biochemical markers of bone turnover have been shown to be useful as inexpensive and noninvasive tools for monitoring skeletal health. The reference range for bone markers in dogs has been set by different age groups. However, other sources of biological variations were not fully investigated in dogs. To explore whether sex influences the interpretation of bone marker data we examined serum bone markers in 33 male and 25 female dogs. The bone markers selected for this study were: bone alkaline phosphatase (BALP) and osteocalcin (OC) as indicators of bone formation, and C-terminal telopeptide (CTx) of type I collagen as marker of bone resorption. All concentrations of bone markers were lower, but still within the reference range reported for dogs. We found statistically significant differences of the median OC and CTx serum concentrations between males and females. The results of this study suggest that there are sex differences in biochemical markers of bone turnover in dogs which should be considered in interpretation of bone marker data.  相似文献   
7.
Methicillin-resistant Staphylococcus aureus (MRSA) have emerged worldwide and have become resistant to a variety of antibiotics. MRSA colonisation in pigs was first reported from the Netherlands in 2005, where pigs were implicated as a source of human MRSA infections (Voss et al., 2005). This paper presents the first report on the presence of MRSA on large pig breeding farms in Croatia, together with the determination of the mecA gene, the results of spa typing and susceptibility to commonly used antimicrobials. Dust samples (7-11 per farm) were collected from eight large pig farms in Croatia. Of the total 68 swabs, the mecA gene was detected in 24 isolates growing on the MRSA agar. All isolates were resistant to oxacillin, tetracycline and streptomycin, and susceptible only to vancomycin, while 92% of the strains were susceptible to ciprofloxacin. Genotyping of the MRSA strains was performed by spa typing, and revealed t011 (n = 17), t034 (n = 5) and t1451 (n = 2). The results presented here predict that MRSA is present on a large number of pig farms in Croatia.  相似文献   
8.
The activity of dopamine beta-hydroxylase (DBH) in plasma ranged from 2 to 100 units per liter of plasma in 82 apparently healthy subjects (ages 22 to 35 years). A nonnormal pattern of distribution was evident: 62 subjects had values below 35 units (18 +/- 1), while 13 of the remaining 20 subjects had values above 60 units (80 +/- 5). Those with low DBH activity had lower values for urinary catecholamine excretion (31 +/- 3 micrograms), with normal and stable blood pressure; those with high DBH activity had higher values for urinary catecholamine excretion (72 +/- 6 micrograms), with greater lability of arterial blood pressure. The DBH activity was significantly elevated in patients with labile (74 +/- 2 mm-Hg) or fixed (57 +/- 2 mm-Hg) essential hypertension. The results indicate that plasma DBH activity is low and that it falls within a narrow range in young adults with normal and stable blood pressure.  相似文献   
9.
10.
Supernova observations show that the expansion of the universe has been speeding up. This unexpected acceleration is ascribed to a dark energy that pervades space. Supernova data, combined with other observations, indicate that the universe is about 14 billion years old and is composed of about 30%matter and 70%dark energy. New observational programs can trace the history of cosmic expansion more precisely and over a larger span of time than has been done to date to learn whether the dark energy is a modern version of Einstein's cosmological constant or another form of dark energy that changes with time. Either conclusion is an enigma that points to gaps in our fundamental understanding of gravity.  相似文献   
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