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21.
Ch unlan Lian Yoshihisa Oi wake Hiromi Yokota Gang Wang Shigeki Konishi 《Soil Science and Plant Nutrition》2013,59(4):695-700
Aluminum (Al) toxicity is a major factor limiting yield production on acid soils (Foy 1983). The initial symptom of Al toxicity in many plants is manifested by the inhibition of root elongation (Ownby and Popham 1990; Llugany et al. 1994; Sasaki et al. 1994; Horst et al. 1997), which occurs during a very short period of time after exposure to Al (Llugany et al. 1994; Staß and Horst 1995). In a large number of recent reports, it was shown that the root apex plays a major role in the Al-sensitivity and response mechanisms (Zhang et al. 1994; Sasaki et al. 1997; Sivaguru and Horst 1998). However, it is interesting to note that stimulatory effects of Al on the growth of plants have also been reported in some studies (Chenery 1955; Konishi et al. 1985; Huang and Bachelard 1993; Osaki et al. 1997). In tea plant (Camellia sinensis L.) a stimulatory effect of Al on the growth was also demonstrated in some experiments, using intact plant (Chenery 1955; Konishi et al. 1985), cultured roots (Tsuji et al. 1994), and pollen tubes (Yokota et al. 1997). The growth of tea roots was typically more stimulated than that of shoots by Al (Konishi et al. 1985). It was assumed that Al effects might be due to the amelioration of phosphorus absorption (Konishi et al. 1985), secretion of malic acid from roots to dissolve aluminum phosphate in the rhizosphere (Jayman and Sivasubramaniam 1975), stimulation of growth of microorganisms on the root surface (Konishi 1990) or replacement of some functions of boron (Konishi 1992; Yokota et al. 1997). However, the stimulatory effects of Al on tea plant growth have not yet been el ucidated. The formation of callose (1,3-β-glucan) has been reported as a common plant response to a variety of stresses, as well as mechanical, biophysical, chemical, and biological injury (Jaffe and Leopold 1984; Zhang et al. 1994). Increased synthesis of callose has been observed upon exposure to excess amounts of some elements, such as boron (McNairn and Currier 1965), cobalt, nickel, zinc (Peterson and Rauser 1979), and manganese (Wissemeier and Horst} 1987, 1992). Callose synthesis was also induced by Al in the roots of Triticum aestivum (Zhang et al. 1994) and Zea mays (Horst et al. 1997; Sivaguru and Horst 1998), suspension-cultured cells of Glycine max (Staß and Horst 1995), and protoplasts of Avena sativa (Schaeffer and Walton 1990) and Zea mays (Wagatsuma et al. 1995). Induction of callose synthesis in roots seems to be a very rapid physiological indicator of Al-induced injury or genotypical differences in Al sensitivity (Wissemeier and Horst 1992; Zhang et al. 1994; Horst et al. 1997). Nevertheless, Al-induced callose synthesis in tea plant, whose growth is stimulated by suitable Al concentrations, has not been described yet. Therefore, to elucidate the physiological basic effects of Al on tea plant, callose synthesis affected by Al in the root tips of intact plants was analyzed in the present study. 相似文献
22.
Paśko P Zagrodzki P Bartoń H Chłopicka J Gorinstein S 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(4):333-338
The effect of Chenopodium quinoa seeds on lipid profile, glucose level, protein metabolism and selected essential elements (Na, K, Ca, Mg) level was determined
in high—fructose fed male Wistar rats. Fructose decreased significantly LDL [42%, p < 0.01] and activity of alkaline phosphatase [20%, p < 0.05], and increased triglycerides level [86%, p < 0.01]. The analysis of blood of rats fed quinoa indicated, that these seeds effectively reduced serum total cholesterol
[26%, p < 0.05], LDL [57%, p < 0.008] and triglycerides [11%, p < 0.05] when compared to the control group. Quinoa seeds also significantly reduced the level of glucose [10%, p < 0.01] and plasma total protein level [16%, p < 0.001]. Fructose significantly decreased HDL [15%, p < 0.05] level in control group but when the quinoa seeds were added into the diet the decrease of HDL level was inhibited.
Quinoa seeds did not prevent any adverse effect of increasing triglyceride level caused by fructose. It was shown in this
study that quinoa seeds can reduce most of the adverse effects exerted by fructose on lipid profile and glucose level. 相似文献
23.
24.
Ch. Iloba 《Forest Pathology》1977,7(1):47-51
Laboratory experiments were conducted to test the effect of various concentrations of Trifluralin on certain fungi. The ectotrophic mycorrhizal fungi tested were: Amanita citrina Schaefer, Tricholoma pessundatum (Fr.) Quel., and Tricholoma saponaceum (Fr.) Qtiel. All exhibited sensitivity to Trifluralin concentrations. The consequence of such fungitoxicity was discussed. 相似文献
25.
Ch. Iloba 《Forest Pathology》1977,7(3):172-177
Pot experiments were performed to investigate the effects of Tritluralin on the mycorrhizal symbiosis of conifer seedlings. Infected forcst soils and potting mixturcs were mixed, pottcd and treated with Trifluralin at levels of 0.2 and 0.4ml/m2 Seeds of Pinus sylvestris L. and Picea abies (L.) Karst. were sown in the pots. The concentrations tested, though recommended by the manufacturer produced phytotoxicity. The seedling growth in general and that of the rootsystem and laceral roots in particular, were severely inhibited. Mycorrhizal development in the seedlings was consequently adversely affected. 相似文献
26.
Ch. Pally 《Journal of pest science》1962,35(10):158-159
Ohne Zusammenfassung 相似文献
27.
Camacho-Hernández IL Chávez-Velázquez JA Uribe-Beltrán MJ Ríos-Morgan A Delgado-Vargas F 《Fitoterapia》2002,73(5):411-413
The methanol extract of the fruit pulp of Bromelia pinguin was evaluated for its antifungal activity. The extract showed a significant activity against some Trichophyton strains, although Candida strains were generally insensitive. 相似文献
28.
The diatomaceous earth (DE) Dryacide® was tested under laboratory conditions on surfaces (2 g DE/m2) and in wheat grain (3 kg DE/t wheat) at a relative humidity of 70±5% and a temperature of 22±1°C. The wheat had a moisture content of 14.5%. The effect of surface treatments was tested onEphestia kuehniella, Oryzaephilus surinamensis, Tenebrio molitor andTribolium castaneum. The efficacy of grain treatments was determined usingEphestia elutella, O. surinamensis, Sitophilus granarius andTribolium confusum. In both treatments adult and larval stages were included.100% mortality were reached with the surface treatments in adults and larvae ofO. surinamensis and the adults ofT. molitor andE. kuehniella after an exposition time of 3–9 days. AgainstT. castaneum and the larvae ofT. molitor andE. kuehniella no complete control could be achieved.In the grain treatments the dosage of 3 kg DE/t wheat reached 100% mortality in all tested pests exceptS. granarius. Most sensitive wereO. surinamensis andE. elutella. InT. confusum the adults died within 13 days of treatment, but for complete control of the larvae 13 weeks were necessary. AgainstS. granarius the silica dust showed no satisfactory efficacy, because 49 days after beginning of the examinations beetles of the progeny hatched. Dryacide® could not prevent the reproduction of the granary weevil, but there was a lower number of progeny compared to the untreated control. 相似文献
29.
Die Fraßtätigkeit von Dermestidenlarven (Dermestes peruvianus Castelnau) in verschiedenen Baustoffen
Ch. Künast 《Journal of pest science》1978,51(9):134-136
20 trials of materials used in buildings have been offered to dermestid larvae to bore in for pupations. Two different types of damage are described. Eight different test substances have been more or less damaged by the larvae. 相似文献
30.
Ch. Kaminsky-Kröger Th. Wilhelmi und J. Bergemann 《Forstwissenschaftliches Centralblatt》1959,78(5-6):180-187
Ohne Zusammenfassung 相似文献