In order to determine the level of resistance of sugar beet varieties against Rhizoctonia solani AG 2-21IIB and AG 4, a methodology was implemented under greenhouse conditions that contemplated the most important crit...In order to determine the level of resistance of sugar beet varieties against Rhizoctonia solani AG 2-21IIB and AG 4, a methodology was implemented under greenhouse conditions that contemplated the most important criteria regarding to plant-pathogen interaction. The effect of plant growth stage on the development of the disease was evaluated. Seven sugar beet varieties were tested for resistance to R. solani AG 2-2IIIB and AG 4. To detect differences in leaf temperature between/L solani inoculated plants and non-infected plants, an infrared （IR） camera was tested. High incidence of R. solani AG 2-2IIIB and AG 4 in sugar beet plants was evident when the fungal inoculum was applied to two and four weeks old plants. At four weeks after sowing, it was the optimum time to inoculate sugar beet plants in order to generate R. solani infection, since at this time all plants were infected. Significant differences were detected regarding disease incidence between sugar beet varieties inoculated with different anastomosis groups. Leaf temperature was significant different between inoculated and non-inoculated plants, demonstrated that this technique could be a new tool for breeders to screen for resistance of new varieties.展开更多
The mercury flux in soils was investigated, which were amended by gypsums from flue gas desulphurization （FGD） units of coal- fired power plants. Studies have been carried out in confined greenhouses using FGD gypsu...The mercury flux in soils was investigated, which were amended by gypsums from flue gas desulphurization （FGD） units of coal- fired power plants. Studies have been carried out in confined greenhouses using FGD gypsum treated soils. Major research focus is uptakes of mercury by plants, and emission of mercury into the atmosphere under varying application rates of FGD gypsum, simulating rainfall irrigations, soils, and plants types. Higher FGD gypsum application rates generally led to higher mercury concentrations in the soils, the increased mercury emissions into the atmosphere, and the increased mercury contents in plants （especially in roots and leaves）. Soil properties and plant species can play important roles in mercury transports. Some plants, such as tall fescue, were able to prevent mercury from atmospheric emission and infiltration in the soil. Mercury concentration in the stem of plants was found to be increased and then leveled off upon increasing FGD gypsum application. However, mercury in roots and leaves was generally increased upon increasing FGD gypsum application rates. Some mercury was likely absorbed by leaves of plants from emitted mercury in the atmosphere.展开更多
文摘In order to determine the level of resistance of sugar beet varieties against Rhizoctonia solani AG 2-21IIB and AG 4, a methodology was implemented under greenhouse conditions that contemplated the most important criteria regarding to plant-pathogen interaction. The effect of plant growth stage on the development of the disease was evaluated. Seven sugar beet varieties were tested for resistance to R. solani AG 2-2IIIB and AG 4. To detect differences in leaf temperature between/L solani inoculated plants and non-infected plants, an infrared （IR） camera was tested. High incidence of R. solani AG 2-2IIIB and AG 4 in sugar beet plants was evident when the fungal inoculum was applied to two and four weeks old plants. At four weeks after sowing, it was the optimum time to inoculate sugar beet plants in order to generate R. solani infection, since at this time all plants were infected. Significant differences were detected regarding disease incidence between sugar beet varieties inoculated with different anastomosis groups. Leaf temperature was significant different between inoculated and non-inoculated plants, demonstrated that this technique could be a new tool for breeders to screen for resistance of new varieties.
基金Financial support for this project was provided by the U.S.Department of Agriculture (No. 6445-12630-003-00D)
文摘The mercury flux in soils was investigated, which were amended by gypsums from flue gas desulphurization （FGD） units of coal- fired power plants. Studies have been carried out in confined greenhouses using FGD gypsum treated soils. Major research focus is uptakes of mercury by plants, and emission of mercury into the atmosphere under varying application rates of FGD gypsum, simulating rainfall irrigations, soils, and plants types. Higher FGD gypsum application rates generally led to higher mercury concentrations in the soils, the increased mercury emissions into the atmosphere, and the increased mercury contents in plants （especially in roots and leaves）. Soil properties and plant species can play important roles in mercury transports. Some plants, such as tall fescue, were able to prevent mercury from atmospheric emission and infiltration in the soil. Mercury concentration in the stem of plants was found to be increased and then leveled off upon increasing FGD gypsum application. However, mercury in roots and leaves was generally increased upon increasing FGD gypsum application rates. Some mercury was likely absorbed by leaves of plants from emitted mercury in the atmosphere.
