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111.
Effects of ground rubber on Phaseolus vulgaris Phaseolus vulgaris was grown in sand culture containing ground rubber. The rubber caused red-brown and black spots and stripes to appear on the veins. The leaves developed widespread chlorosis. The vascular bundle tissues and the mesophyll differentiated incorrectly. Brown deposits were found in all tissues, some being manganese enriched. Plants were analysed for Boron, Cadmium, Manganese and Zinc after a vegetation period of 49 days. Zinc toxicity was considered ground rubber's primary effect. It also caused Boron starvation and excess of Manganese.  相似文献   
112.
The effects of the commonly used processing techniques of soaking (at different pH values) and cooking on the digestive and nutritive utilization of calcium, phosphorus, and magnesium from common beans (Phaseolus vulgaris L.) were studied. Before the cooking step, the beans were soaked in solutions of acid (2.6 and 5.3) or basic (8.4) pH. Chemical and biological methods were used to determine nutritional parameters in growing rats, and the fiber content of the beans was established. As the pH of the soaking solution increased, so did mineral absorption and the apparent digestibility coefficient, which reached suitable values for growing rats, due to the reduced losses of soluble minerals and the increased food intake. Metabolic utilization also improved with increased pH of the soaking solution, although the values were, in general, low as a result of urinary losses under the experimental conditions. For the experimental period of 10 days, the femur and the muscle seem to be good metabolic indicators for calcium, but not for phosphorus or magnesium. The increased amount of cellulose in the soaked seed did not have a negative effect on the digestive utilization of minerals.  相似文献   
113.
The effects of sixteen metal ions: Al, Cd, Co(II), Cr(III), Cr(VI), Cu(II), Fe(III), Li, Mg, Mn(H), Mo(VI), Ni(II), Pb(II), Se(IV), V(V), and Zn on the mortality and infectivity of Steinernema carpocapsae were observed in 96 hour laboratory tests. All ions except Cu(II), Pb(II), and Zn even at naturally unrealistic concentrations did not cause the mortality of S. carpocapsae. However, such treatment lowered infectivity of nematodes with respect to wax moth caterpillars, Galleria mellonella.  相似文献   
114.
The principal goal of this paper was to generate flax (Linum usitatissimum L.) plants with increased antioxidant properties. To accomplish this a vector containing a multigene construct was prepared, and transgenic plants overexpressing essential flavonoid biosynthesis pathway enzymes were generated and analyzed. The simultaneous expression of genes encoding chalcone synthase (CHS), chalcone isomerase (CHI), and dihydroflavonol reductase (DFR) resulted in a significant increase of flax antioxidant capacity. To investigate the determinants of higher antioxidant properties of transgenic plants, the phenolic acids and lignans compound contents were measured. In both green part and seed extracts from transgenic plants, the phenolic acids level was increased when compared to the control. The calculated correlation coefficient between phenolic acids content and antioxidant capacity (0.82 and 0.70 for green part and flaxseed, respectively) perfectly reflects their strong relationship. The increase in yield of transgenic plants and their higher resistance to Fusarium culmorum and Fusarium oxysporum when compared to the control plants was a characteristic feature. It was assessed a very high correlation (correlation coefficient = 0.9) between phenolic acids level in flaxseed extract and resistance to F. culmorum. The flowering date of transgenic plants was approximately 3 weeks earlier than that of the control plants. Interestingly, a significant increase in monounsaturated fatty acids and a slight increase in lignans content accompanied the increase in antioxidant properties of flaxseeds.  相似文献   
115.
Phosphorus (P) sorption processes in soils contribute to important problems in agriculture: a deficiency of this plant nutrient and eutrophication in aquatic systems. Soil organic matter (SOM) plays a major role in sorption processes, but its influence on P sorption remains unclear and needs to be elucidated to improve the ability to effectively manage soil P. The aim of this research was to investigate the influence of SOM on P sorption. The study was conducted in sandy soil profiles and in topsoils before and after removal of SOM with H2O2. The results were interpreted with the Langmuir and Freundlich isotherms. Our results indicated that SOM affected P sorption in sandy soils, but that P sorption also depended on specific soil properties (e.g. values of the degree of P saturation (DPS), P sorption capacity (PSC) and pH) often related to land use. Removal of SOM decreased PSC in most of the topsoils tested; other soil properties became important in controlling P sorption. An increase in P desorption observed after SOM removal indicated that SOM was potentially that soil constituent which increased P binding and limited P leaching from these sandy soils.  相似文献   
116.
In declining broadleaf forests in western Ukraine, several Phytophthora species including P. plurivora, P. bilorbang, P. polonica, P. gonapodyides and P. cactorum were recovered using soil baiting assays and identified using morphological and molecular methods. Pathogenicity tests of selected isolates were performed on black alder (Alnus glutinosa (L.) Gaerth.) and silver birch (Betula pendula Roth.) to assess susceptibility of these two tree species to the newly detected Phytophthora species. Phytophthora plurivora, P. bilorbang and P. polonica showed higher pathogenicity in both alder and birch compared to the other tested Phytophthora species.  相似文献   
117.
118.
Rural women did not fare very well inthe land reforms carried out during the Latin Americanreformist period of the 1960s and 1970s, with womenbeing under-represented among the beneficiaries. It isargued that women have been excluded from access toand control over water for similar reasons that theywere excluded from access to land during thesereforms. The paper also investigates the extent towhich women have gained or lost access to land duringthe counter-reforms of the 1980s and 1990s. Underthe neo-liberal agenda, production cooperatives aswell as communal access to land have largely beenundermined in favor of privatization and theindividual parcelization of collectives. Significantland titling efforts are also being carried outthroughout the region to promote the development of avigorous land market. This latter period has also beencharacterized by the growth of the feminist movementthroughout Latin America and a growing commitment bystates to gender equity. The paper reviews the extentto which rural womens access to land and, thus, waterhas potentially been enhanced by recent changes inagrarian and legal codes.  相似文献   
119.
New Forests - Populus nigra ‘Italica’ (Lombardy poplar) is a breeding cultivar of black poplar, widely used as a street tree or windbreak, often exposed to salinity and limited water...  相似文献   
120.
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