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71.
The history of hyperplastic canker of almond, caused by Pseudomonas amygdali , its evolution and the present situation in Greece are reviewed. Its main aspects, causal agent, symptomatology, epidemiology and control measures are described. The main characteristics differentiating the pathogen from some other pseudomonads pathogenic to fruit trees are also reported.  相似文献   
72.
Abstract. In Australia, stubble burning and tillage are two of the major processes responsible for the decline of soil organic carbon concentration in cropped soils, and the resulting soil degradation. However, the relative importance of these two practices in influencing the soil organic carbon concentration and the long-term impact on soil quality and productivity are not clear. The effects of stubble burning as practised by farmers in southeastern Australia were evaluated in two field trials, one of 19 years duration, the other of 5 years. Conventional tillage (three tillage passes) led to greater loss of soil organic carbon than stubble burning. Loss of total soil organic carbon attributed to stubble burning in the 0–10 cm layer was estimated to be 1.75 t C ha−1 over the period of the 19-year trial, equivalent to 29% of that lost due to tillage. In the 5-year trial, no change in soil organic carbon due to stubble burning was detectable. Changes in soil quality associated with stubble burning detected in the longer trial included a reduction in macro-aggregate stability, and increases in pH and exchangeable K+. Only the latter two were detected in the shorter trial. A higher mean wheat yield (average 0.15 t ha−1) following stubble burning was observed in the 19-year trial but not in the 5-year trial. Research to monitor the longer term effects of stubble burning is needed, and to identify conditions where loss of soil organic carbon is minimized.  相似文献   
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74.
Field experiments were conducted at Tamil Nadu Rice Research Institute, Aduthurai, India, during the wet seasons of 1992 and 1993 to study the effect of full and partial substitution of fertiliser N with green manure N (Sesbania rostrata) on nitrogen uptake, yield attributes and yield of rice. The experiment consisted of eight treatments with two levels of N (100 and 200 kg ha−1) and three sources of N application viz., fertilizer, integrated (1:1 fertilizer and green manure N) and green manure N compared to the recommended practice (150 kg fertilizer plus 6.25 t ha−1 (72 kg N) green manure) and a no N control. Nitrogen application markedly increased the N uptake. Combined use of the two N sources at 200 and 222 kg N ha−1 and of single fertilizer N at 200 kg N ha−1 recorded the maximum N uptake, increased the yield attributes such as number of panicles per unit area, weight per panicle, number of total and filled grains per panicle and test weight. At 200 kg N ha−1 full substitution of N by green manure reduced the grain yield but only partial substitution of N by green manure resulted in almost similar yield as single fertilizer N. Thus 200 kg N ha−1 applied in equal proportions of fertilizer and green manure N can be recommended for medium duration rice cultivars.  相似文献   
75.
The effect of ultraviolet irradiation on some biochemical indicators of bone turnover in dairy cows was determined. The irradiation was performed using a stationary system for two months and comprised a regimen of 10 days irradiation followed by 10 days rest. After ultraviolet irradiation, significant differences in the activities of serum alkaline phosphatase (P < 0.001) and bone alkaline phosphatase isoenzyme (P < 0.05) and concentration of osteocalcin (P < 0.01) were demonstrated. The results suggest that supplementary ultraviolet irradiation during winter could be used as a simple but reliable method of preventing the development of generalised metabolic bone disorders in dairy cows.  相似文献   
76.
Sevoflurane and desflurane are volatile inhaled anesthetics that are currently being investigated as possible improvements for the anesthetic management of human patients. Information to date suggests these agents have several advantages over existing clinical agents. For example, the blood/gas partition coefficient for both agents is lower than that of other halogenated anesthetics. Consistent with this physical characteristic is a more rapid induction of and emergence from anesthesia. Both cause a dose-related depression of cardiopulmonary function, which is comparable to isoflurane. Results of studies to date favor desflurane over sevoflurane because it is less soluble in blood, is stable in soda lime, is biodegraded the least of any volatile anesthetic, and is not toxic.  相似文献   
77.
Plasma cortisol and corticosterone levels were measured in macaws, African Grey Parrots, Amazon Parrots and budgerigars using a RIA after preliminary cleaning. As in other avian species, the plasma contains predominantly corticosterone.  相似文献   
78.
79.
The levels of oestradiol-17 beta (E2) in the blood plasma were evaluated in 15 boars exhibiting signs of sexual potency disorders and in 20 boars with no such disorders before and after i. v. administration of chorion gonadotropin (HCG). No significant difference (P greater than 0.05) was found in the E2 levels in the blood plasma of the boars of the two groups before HCG administration. Two hours after the i. v. injection of 500 I. U. of HCG, an insignificant increase in the basal levels of E2 was recorded, reaching on the average 28.9% in the boars with potency disorders and 38.8% in those with no potency changes. Neither were there any significant differences in the E2 levels determined after HCG treatment between the boars with and without sexual potency disorders. It is inferred from the results that deviations in E2 concentration in the blood obviously do not contribute significantly to disorders in the sexual potency of boars.  相似文献   
80.
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