ミツマタの生育に及ぼす温度の影響

抄録

The influences of air temperature on the growth of mitsumata under pot conditions, were examined from the view point of dry matter production. The results were summarized as follows: 1. The apparent photosynthetic rate was light-saturated at about 20 klx, though slight depression was observed above 40 klx, when the plants were grown under 50% shading (Fig. 1). The optimum temperature of apparent photosynthesis was found at about 26°C. The respiratory rate increased from 20 to 40°C with 1.98 of Q₁₀ value (Fig. 2). 2. The Relative Growth Rate (RGR) increased with increasing air temperature from 15 to 25°C. The Net Assimilation Rate (NAR) showed the same behaviour to RGR. The Leaf Area Ratio (LAR) decreased with increasing air temperature (Fig. 3). The rate of apparent photosynthesis grown under 25, 20 and 15°C for about 90 days, was the highest at 24, 21 and about 15°C, respectibly (Fig. 4). 3. The length of the new shoot and the thickness of the stem decreased markedly at 30°C, and the ratio of the stem thickness to the shoot length was the highest at 20°C (Fig. 5 and Fig. 6).