[Objective] The aim was to explore a suitable cultivation approach for cassava in Hunan province. [Method] With SC9(Southern China 9) as test materials, the test included four treatment methods, as follows: control gr...[Objective] The aim was to explore a suitable cultivation approach for cassava in Hunan province. [Method] With SC9(Southern China 9) as test materials, the test included four treatment methods, as follows: control group by traditional cultivation with crops uncovered(CK), treatment 1 by traditional cultivation with mulch coverage, treatment 2 by powder ridge cultivation with crops uncovered, and treatment 3 by powder ridge cultivation with mulch coverage. Water and fertilizer managements were kept the same. [Result] Compared with traditional cultivation(CK), the treatment by powder ridge cultivation with mulch coverage performed better. Specifically, yield per unit area reached 44 790 kg/hm2, increasing by 86.38%(20 760 kg/hm2) than that of control; starch content grew by 17.24%. The cultivation method considerably improved cassava yield and quality. [Conclusion] Powder ridge cultivation with mulch coverage is a cultivation approach suitable for cassava in Hunan province.展开更多
[Objective] The aim was to measure photosynthetic characters of SC 205, a cassava cultivar, and explore the relationships of the net photosynthetic rate(Pn) with physiological and ecological factors. [Method] The diur...[Objective] The aim was to measure photosynthetic characters of SC 205, a cassava cultivar, and explore the relationships of the net photosynthetic rate(Pn) with physiological and ecological factors. [Method] The diurnal variations of photosynthesis in leaves of SC205 were studied by LICOR-6400 portable photosynthesis system, and the relationships of the net photosynthetic rate(Pn) with physiological and ecological factors were studied by simple correlation analysis and path analysis. [Result] The curve of diurnal variation of Pn showed single peak at 10:00 am at 24.07 μ mol CO2m2/s, without showing midday depression; the diurnal changes of stomatal conductance(Gs), transpiration rate(Tr), leaf temperature(Tl), air temperature(Ta) and photosynthetic active radiation(PAR) all showed single peak curves, and there were positive relationships of Pn with Gs, Tr, Tl, Ta and PAR. The diurnal variations of intercellular CO2concentration(Ci), atmospheric CO2concentration(Ca), relative humidity(RH) showed in a U-shape curve. There were highly significant positive correlation of Pn with Gs and PAR; the diurnal variation of Pn had highly significant negative correlations with Ci and Ca. The direct impact of physiological factors on Pn was as follows: Ci>Gs>Tl>Tr, and the direct impact of ecological factors was RH >PAR >Ca >Ta. [Conclusion] The research showed that Ci, Gs and Tr play very important roles in the changes of Pn among the physiological factors, and PAR and Ca affect the changes of Pn among the ecological factors.展开更多
基金Supported by the Earmarked Fund for China Agriculture Research System(CARS-12cssy)
文摘[Objective] The aim was to explore a suitable cultivation approach for cassava in Hunan province. [Method] With SC9(Southern China 9) as test materials, the test included four treatment methods, as follows: control group by traditional cultivation with crops uncovered(CK), treatment 1 by traditional cultivation with mulch coverage, treatment 2 by powder ridge cultivation with crops uncovered, and treatment 3 by powder ridge cultivation with mulch coverage. Water and fertilizer managements were kept the same. [Result] Compared with traditional cultivation(CK), the treatment by powder ridge cultivation with mulch coverage performed better. Specifically, yield per unit area reached 44 790 kg/hm2, increasing by 86.38%(20 760 kg/hm2) than that of control; starch content grew by 17.24%. The cultivation method considerably improved cassava yield and quality. [Conclusion] Powder ridge cultivation with mulch coverage is a cultivation approach suitable for cassava in Hunan province.
基金Supported by the Earmarked Fund for China Agriculture Research System(CARS-12)
文摘[Objective] The aim was to measure photosynthetic characters of SC 205, a cassava cultivar, and explore the relationships of the net photosynthetic rate(Pn) with physiological and ecological factors. [Method] The diurnal variations of photosynthesis in leaves of SC205 were studied by LICOR-6400 portable photosynthesis system, and the relationships of the net photosynthetic rate(Pn) with physiological and ecological factors were studied by simple correlation analysis and path analysis. [Result] The curve of diurnal variation of Pn showed single peak at 10:00 am at 24.07 μ mol CO2m2/s, without showing midday depression; the diurnal changes of stomatal conductance(Gs), transpiration rate(Tr), leaf temperature(Tl), air temperature(Ta) and photosynthetic active radiation(PAR) all showed single peak curves, and there were positive relationships of Pn with Gs, Tr, Tl, Ta and PAR. The diurnal variations of intercellular CO2concentration(Ci), atmospheric CO2concentration(Ca), relative humidity(RH) showed in a U-shape curve. There were highly significant positive correlation of Pn with Gs and PAR; the diurnal variation of Pn had highly significant negative correlations with Ci and Ca. The direct impact of physiological factors on Pn was as follows: Ci>Gs>Tl>Tr, and the direct impact of ecological factors was RH >PAR >Ca >Ta. [Conclusion] The research showed that Ci, Gs and Tr play very important roles in the changes of Pn among the physiological factors, and PAR and Ca affect the changes of Pn among the ecological factors.
