title: [Comparative study on daily change of photosynthesis rate of the rhizomatous grasses in milky ripe stage].
abstract: Comparative study on daily change of photosynthesis rate of the rhizomatous grasses in their milky ripe stage was carried out, and the results showed that photosynthetic rate of five grasses appeared to be two-apex curve, except Elytrigia intermedia appeared to be one-apex curve. The general trend was that the higher the root/shoot ratio was, the later the first apex of the photosynthetic rate reached, and the shorter the noon break period was. Moreover, low relative humidity and high leaf temperature were the important factors for noon break. Leymus chinense, Pascopyrum smithii Rydb. cn. Rosana, Leymus secalinus, Leymus racemosus, Agropyron mongolicum and Elytrigia intermedia reached the first apex at 10:12, 10:00, 9:51, 9:39, 9:06 and 8:13, the noon break period was 471, 474, 464, 467 and 551 min, and the average leaf temperature during noon break was 37.8, 37.5, 36.9, 37.0 and 36.3 degrees C, respectively. Leymus chinense and Agropyron mongolicum, Leymus secalinus and Leymus racemosus had similar daily change in photosynthetic rate, respectively, and their r values were 0.88 and 0.96 respectively when R = 0.01.
authors.affiliation: College of Life Science, Sichuan University, Chengdu 610065, China. hwx062985.student@sina.com.cn
authors.forename: Wenxing
authors.initials: W
authors.lastname: He
authors.forename: Jin
authors.initials: J
authors.lastname: Yi
authors.forename: Hongmei
authors.initials: H
authors.lastname: Li
mesh_terms: D031702:Agropyron / Q000254:growth & development / Q000378:metabolism; D006813:Humidity; D010788:Photosynthesis; D018515:Plant Leaves / Q000378:metabolism; D006109:Poaceae / Q000254:growth & development / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors