中国北方杂草稻光合与水分生理特性

Photosynthetic and water physiological characteristics of weedy rice in northern China

杂草稻是一类重要的稻属种质资源，具有耐寒、耐旱、耐瘠薄等优良特性．本文以88份中国北方杂草稻资源和4份栽培稻为材料，研究了中国北方杂草稻的光合速率、蒸腾速率、气孔导度等光合与水分生理特性及其相互关系．结果表明：北方杂草稻资源的光合和水分生理特性存在较大差异，具有丰富的多样性．杂草稻的光合速率变化范围在12．47～28．67μmol CO2.m-2·s-1，瞬时水分利用效率的变化范围在1．39～3．40mg·g-1．光合参数中，胞间CO2浓度的变异系数最小，气孔导度的变异系数最大．光合速率与蒸腾速率、气孔导度呈极显著的二次曲线关系，光合速率与胞间CO2浓度呈显著的直线关系，瞬时水分利用效率与蒸腾速率、气孔导度呈极显著的二次曲线关系．可用杂草稻材料的优越性能对栽培稻进行品种改良．

Abstract： Weedy rice is an important germplasm source of rice, which has the characteristics of cold-, drought-, and barren tolerance. Taking 88 accessions of weedy rice and 4 varieties of culti- vated rice in northern China as test materials, this paper studied the photosynthetic characteristics （photosynthetic rate, transpiration rate, and stomatal conductance） , water physiological character- istics, and their interrelationships of weedy rice in northern China. There existed greater differences in the photosynthetic and water physiological characteristics among the weedy rice accessions, pos- sessing abundant diversity. The photosynthetic rate of the accessions was from 12.47 μmol CO2. ,-2.s -1 to 28.67 μmol CO2 .m-2. s-1, and the instantaneous water use efficiency was from 1.39 -1 mg . g-1 to 3.40 mg. g-1. Among the photosynthetic parameters intercellular CO2 concentrauon had the smallest variable coefficient, while stomatal conductance had the largest one. The photosyn- thetic rate had significant conic relationships with transpiration rate and stomatal conductance, and had a linear relationship with intercellular CO2 concentration. The significant conic relationships also existed between the instantaneous water use efficiency and the transpiration rate and stomatal conduct- ance. The excellent features of weedy rice could be used to improve the cultivated rice varieties.