Photosynthetic and growth responses of Japanese sasabamo (Potamogeton wrightii Morong) under different photoperiods and nutrient conditions

作者：Sultana Munira^*; Asaeda Takashi; Azim M Ekram; Fujino Takeshi

来源：Chemistry and Ecology, 2010, 26(6): 467-477.

DOI：10.1080/02757540.2010.522995

• Potamogeton wrightii
• nutrient
• dark respiration
• photoperiod

Controlled laboratory experiments were conducted to examine how photosynthesis and growth occur in Potamogeton wrightii Morong under different photoperiods and nutrient conditions. The experiment was based on a 3x2 factorial design with three photoperiods (16, 12 and 8h) of 200E center dot m-2 center dot s-1 irradiance and two nutrient conditions, high (90molN center dot L-1 center dot d-1 and 9molP center dot L-1 center dot d-1) and low (30molNL-1 center dot d-1 and 3molP center dot L-1 center dot d-1). After 14, 28, 56 and 70 days of growth, plants were harvested to determine net photosynthesis rate and various growth parameters. Above- and below-ground biomass were investigated on days 56 and 70 only. Plants under low nutrient conditions had greater leaf area, more chlorophyll a, a higher rate of net photosynthesis and accumulated more above- and below-ground biomass than plants in the high nutrient condition. Plants with an 8h photoperiod in the low nutrient condition had a significantly higher rate of net photosynthesis, whereas 8h photoperiod plants in the high nutrient condition had a lower rate of net photosynthesis and their photosynthetic capacity collapsed on day 70. We conclude that P. wrightii has the photosynthetic plasticity to overcome the effects of a shorter photoperiod under a tolerable nutrient state.

• 出版日期2010