A special kind of rice field exists in China that is flooded year-round. These rice fields have substantially large CH4 emissions during the rice-growing season and emit CH4 continuously in the non-rice growing season...A special kind of rice field exists in China that is flooded year-round. These rice fields have substantially large CH4 emissions during the rice-growing season and emit CH4 continuously in the non-rice growing season. CH4 emission factors were used to estimate the CH4 emissions from year-round flooded rice fields during the rice-growing season in China. The CH4 emissions for the year-round flooded rice fields in China for the rice growing season over a total area of 2.66 Mha were estimated to be 2.44 Tg CH…展开更多
Effect of intermittent irrigation on the production of paddy rice was studied in a well-puddled paddy field with four treatments and 2 replicates: continuous flooding irrigation (CFI), and intermittent irrigation Ⅱ-...Effect of intermittent irrigation on the production of paddy rice was studied in a well-puddled paddy field with four treatments and 2 replicates: continuous flooding irrigation (CFI), and intermittent irrigation Ⅱ-O, Ⅱ-1 and Ⅱ-2, in which plants were re-irrigated when the soil water potential fell below 0, -10, and -20 kPa, respectively, at soil depth of about 5 cm. Results showed that the reduction in soil water potential to about -10 or -20 kPa did not significantly affect the number of grains and the percentage of ripened grains. While, a lower crop growth rate (CGR) resulted from a decrease in the net assimilation rate (NAR) during intermittent irrigation Ⅱ-1 and Ⅱ-2, and there was also a reduction in the leaf area index (LAI) during intermittent irrigation Ⅱ-2. Senescence of lower leaves on stems was promoted in treatments Ⅱ-1 and Ⅱ-2 at the ripening stage. Early senescence at ripening stage and water stress around midday decreased the rate of photosynthesis in leaves, causing the lower NAR. These physiological responses of the plants were responsible for the reduction in the dry matter production and grain yield in the intermittent irrigation treatments.展开更多
To introduce CMV resistance to susceptible variety, interspecific grafting between d45-6 (Capsicum annuum) and LS1205 (C. baccatum) was conducted. The graft-progenies, G1 and G1S1 were obtained. Mechanical inoculation...To introduce CMV resistance to susceptible variety, interspecific grafting between d45-6 (Capsicum annuum) and LS1205 (C. baccatum) was conducted. The graft-progenies, G1 and G1S1 were obtained. Mechanical inoculation with CMV showed that disease index of G1 and G1S1 were significantly decreased, similar to that of the resistant stock. ELISA serological test indicated that resistance of LS1205 and the graft-progenies to CMV was caused by inhibition of virul replication. Further, peroxidase isozymatic analysis revealed that zymotypes of G1 were a summation of those found in the donor plants. This result perfectly fit the theory of gene transformation and reconfirmed the conclusion of mechanism of graft-induced variants.展开更多
文摘A special kind of rice field exists in China that is flooded year-round. These rice fields have substantially large CH4 emissions during the rice-growing season and emit CH4 continuously in the non-rice growing season. CH4 emission factors were used to estimate the CH4 emissions from year-round flooded rice fields during the rice-growing season in China. The CH4 emissions for the year-round flooded rice fields in China for the rice growing season over a total area of 2.66 Mha were estimated to be 2.44 Tg CH…
基金Project (No. 49971043) supported partly by the National Natural Science Foundation of China.
文摘Effect of intermittent irrigation on the production of paddy rice was studied in a well-puddled paddy field with four treatments and 2 replicates: continuous flooding irrigation (CFI), and intermittent irrigation Ⅱ-O, Ⅱ-1 and Ⅱ-2, in which plants were re-irrigated when the soil water potential fell below 0, -10, and -20 kPa, respectively, at soil depth of about 5 cm. Results showed that the reduction in soil water potential to about -10 or -20 kPa did not significantly affect the number of grains and the percentage of ripened grains. While, a lower crop growth rate (CGR) resulted from a decrease in the net assimilation rate (NAR) during intermittent irrigation Ⅱ-1 and Ⅱ-2, and there was also a reduction in the leaf area index (LAI) during intermittent irrigation Ⅱ-2. Senescence of lower leaves on stems was promoted in treatments Ⅱ-1 and Ⅱ-2 at the ripening stage. Early senescence at ripening stage and water stress around midday decreased the rate of photosynthesis in leaves, causing the lower NAR. These physiological responses of the plants were responsible for the reduction in the dry matter production and grain yield in the intermittent irrigation treatments.
文摘To introduce CMV resistance to susceptible variety, interspecific grafting between d45-6 (Capsicum annuum) and LS1205 (C. baccatum) was conducted. The graft-progenies, G1 and G1S1 were obtained. Mechanical inoculation with CMV showed that disease index of G1 and G1S1 were significantly decreased, similar to that of the resistant stock. ELISA serological test indicated that resistance of LS1205 and the graft-progenies to CMV was caused by inhibition of virul replication. Further, peroxidase isozymatic analysis revealed that zymotypes of G1 were a summation of those found in the donor plants. This result perfectly fit the theory of gene transformation and reconfirmed the conclusion of mechanism of graft-induced variants.
