[Effects of rhizosphere CO2 concentration on potato growth]

With the method of areoponics, this paper established a rhizosphere gas environment research system to study the effects of different rhizosphere CO2 concentration on the growth of potato (Solanum tuberosum) plants. The results showed that in treatments 380 and 380 approximately 920 micromol CO2 x mol(-1), the plant height, stem diameter, leaf area, root length, and individuals of stolon and mini-tuber had a similar variation trend with time, and presented two distinct phases. The plants grew vigorously, and their tuber yield increased markedly, compared with treatment 3,600 micromol CO2 x mol(-1), which indicated that 380 approximately 920 micromol CO2 x mol(-1) was the appropriate CO2 concentration in the root zone to promote potato growth, while overmuch rhizosphere CO2 would markedly inhibit the growth and development of potato plants. Treatment 3,600 micromol CO2 x mol(-1) and sand culture had the similar stem diameter, leaf area, and individuals of stolon and mini-tuber. The plants grew short and weak, and tuber yield was lower.