[ Objective ] The study aimed to screen rational seedling raising date and seedling raising mode for plateau japonica rice, in order to reduce the effect of low temperature on seedlings. [ Method ] The seedlings of co...[ Objective ] The study aimed to screen rational seedling raising date and seedling raising mode for plateau japonica rice, in order to reduce the effect of low temperature on seedlings. [ Method ] The seedlings of conventional japonica rice Hexi 22-2 and giant embryo No. 1 japonica rice were treated at day tempera- ture 12℃/night temperature 8℃ and day temperature 14 ℃/night temperature 10 ℃, and the indicators including chlorophyll content, soluble sugar content, sol- uble protein content, survival rate, plant height, number of ≥ 1 cm roots, leaf wilting degree and aboveground dry matter weight were determined after treated for 0, 3 and 6 d, respectively. [ Result] Chlorophyll content of seedlings decreased when treated by low temperature for a certain period; with the prolongation of treat- ment time, contents of soluble sugar and soluble protein in some low temperature treatments increased, while plant height, number of ≥ 1 cm roots and aboveground dry matter weight increased slowly, but the growth rate was significantly lower than that at room temperature; with the decrease of temperature and the prolongation of treatment time, leaf wilting degree increased. The comprehensive experimental results showed that with the increasing duration of low temperature, when two japonica rice varieties grew under the same low temperature, seedlings grew more and more slowly, probably because the lower the treatment temperature, the greater the damage on plants. Giant Embryo No. 1 had weaker cold tolerance than Hexi 22-2. [ Conclusion] The study provides a theoretical basis for formula- tion of seedling raising technique of plateau japonica rice.展开更多
Soil erosion on farmland is a critical environmental issue and the main source of sediment in the Yellow River, China. Thus, great efforts have been made to reduce runoff and soil loss by restoring vegetation on aband...Soil erosion on farmland is a critical environmental issue and the main source of sediment in the Yellow River, China. Thus, great efforts have been made to reduce runoff and soil loss by restoring vegetation on abandoned farmland. However, few studies have investigated runoff and soil loss from sloping farmland during crop growth season. The objective of this study was to investigate the effects of soil management on runoff and soil loss on sloping farmland during crop growth season. We tested different soybean growth stages (i.e., seedling stage (R1), initial blossoming stage (R2), full flowering stage (R3), pod bearing stage (R4), and initial filling stage (R5)) and soil management practice (one plot applied hoeing tillage (HT) before each rainfall event, whereas the other received no treatment (NH)) by applying simulated rainfall at an intensity of 80 mm/h. Results showed that runoff and soil loss both decreased and infiltration amount increased in successive soybean growth stages under both treatments. Compared with NH plot, there was less runoff and higher infiltration amount from HT plot. However, soil loss from HT plot was larger than that from NH plot in R1–R3, but lower in R4 and R5. In the early growth stages, hoeing tillage was effective for reducing runoff and enhancing rainfall infiltration. By contrast, hoeing tillage enhanced soil and water conservation during the late growth stages. The total soil loss from HT plot (509.0 g/m2) was 11.1% higher than that from NH plot (457.9 g/m2) in R1–R5. However, the infiltration amount from HT plot (313.9 mm) was 18.4% higher than that from NH plot (265.0 mm) and the total runoff volume from HT plot was 49.7% less than that from NH plot. These results indicated that crop vegetation can also act as a type of vegetation cover and play an important role on sloping farmland. Thus, adopting rational soil management in crop planting on sloping farmland can effectively reduce runoff and soil loss, as well as maximize rainwater infiltration during crop growth period.展开更多
基金Supported by Key Scientific Research Project of Sichuan Provincial Department of Education "Cultivation Physiology and Technique of Plateau Japonica Rice"(10ZA067)
文摘[ Objective ] The study aimed to screen rational seedling raising date and seedling raising mode for plateau japonica rice, in order to reduce the effect of low temperature on seedlings. [ Method ] The seedlings of conventional japonica rice Hexi 22-2 and giant embryo No. 1 japonica rice were treated at day tempera- ture 12℃/night temperature 8℃ and day temperature 14 ℃/night temperature 10 ℃, and the indicators including chlorophyll content, soluble sugar content, sol- uble protein content, survival rate, plant height, number of ≥ 1 cm roots, leaf wilting degree and aboveground dry matter weight were determined after treated for 0, 3 and 6 d, respectively. [ Result] Chlorophyll content of seedlings decreased when treated by low temperature for a certain period; with the prolongation of treat- ment time, contents of soluble sugar and soluble protein in some low temperature treatments increased, while plant height, number of ≥ 1 cm roots and aboveground dry matter weight increased slowly, but the growth rate was significantly lower than that at room temperature; with the decrease of temperature and the prolongation of treatment time, leaf wilting degree increased. The comprehensive experimental results showed that with the increasing duration of low temperature, when two japonica rice varieties grew under the same low temperature, seedlings grew more and more slowly, probably because the lower the treatment temperature, the greater the damage on plants. Giant Embryo No. 1 had weaker cold tolerance than Hexi 22-2. [ Conclusion] The study provides a theoretical basis for formula- tion of seedling raising technique of plateau japonica rice.
基金financially supported by the National Natural Science Foundation of China (41390464, 41571130083, 41271288)
文摘Soil erosion on farmland is a critical environmental issue and the main source of sediment in the Yellow River, China. Thus, great efforts have been made to reduce runoff and soil loss by restoring vegetation on abandoned farmland. However, few studies have investigated runoff and soil loss from sloping farmland during crop growth season. The objective of this study was to investigate the effects of soil management on runoff and soil loss on sloping farmland during crop growth season. We tested different soybean growth stages (i.e., seedling stage (R1), initial blossoming stage (R2), full flowering stage (R3), pod bearing stage (R4), and initial filling stage (R5)) and soil management practice (one plot applied hoeing tillage (HT) before each rainfall event, whereas the other received no treatment (NH)) by applying simulated rainfall at an intensity of 80 mm/h. Results showed that runoff and soil loss both decreased and infiltration amount increased in successive soybean growth stages under both treatments. Compared with NH plot, there was less runoff and higher infiltration amount from HT plot. However, soil loss from HT plot was larger than that from NH plot in R1–R3, but lower in R4 and R5. In the early growth stages, hoeing tillage was effective for reducing runoff and enhancing rainfall infiltration. By contrast, hoeing tillage enhanced soil and water conservation during the late growth stages. The total soil loss from HT plot (509.0 g/m2) was 11.1% higher than that from NH plot (457.9 g/m2) in R1–R5. However, the infiltration amount from HT plot (313.9 mm) was 18.4% higher than that from NH plot (265.0 mm) and the total runoff volume from HT plot was 49.7% less than that from NH plot. These results indicated that crop vegetation can also act as a type of vegetation cover and play an important role on sloping farmland. Thus, adopting rational soil management in crop planting on sloping farmland can effectively reduce runoff and soil loss, as well as maximize rainwater infiltration during crop growth period.
