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51.
Daily measurement of gas exchanges during a complete growth cycle: photosynthesis, transpiration and night respiration in a soil culture of maize. During a complete growth cycle, photosynthesis (P), night-respiration (R) and transpiration (T) have been measured daily for maize (Zea mays L. cv. INRA F7 × F2) in a self-regulating growth chamber. P and T varied according to three different kinetics. During the growing period there was a fast and concomitant variation of both P and T, which could be filled to a power function of time. During the fructification period we observed a linear decrease of P and T. Finally, during the senescence period P decreased to zero, whereas T kept a value higher than the evaporation of the naked soil. In the first two periods, the P/T ratio decreased as leaves aged. From this we could deduce that a slow increase of stomatal resistance (RS) and mesophyll resistance (RM) took place. R increased until the panicle appeared; it remained constant during fructification and then it decreased with senescence. Each nitrogen supply induced a transient increase of R. Finally, a water stress led to a greater decrease of P than of R, but the after effect of water stress disappeared a day later. These results were compared with those obtained in hydroponic conditions. 相似文献
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VIII. CRUSTACEA: ANOSTRACA AND CONCHOSTRACA 总被引:1,自引:0,他引:1
J. P. HARDING PH. D. 《Zoological Journal of the Linnean Society》1940,1(2):149-153
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Yverlin Z Pruvot Lily-Arison René de Roland Gilbert Razafimanjato Marius PH Rakotondratsima Aristide Andrianarimisa Russell Thorstrom 《Ostrich》2018,89(2):109-115
We studied the nesting biology and food habits of the endangered and endemic Sakalava Rail Amaurornis olivieri from July to November 2015 in the Mandrozo Protected Area, western Madagascar. Three nesting pairs were observed and their nests were constructed in a dense mat of reeds Phragmites mauritianus and averaged 56.7 ± 15.3 cm above the water (n = 3 nests). Nests were built by both adults and it took 3 d on average to complete a nest (n = 2 nests). Thirteen matings were observed and lasted 4.1 s on average (n = 2 pairs). Average clutch size was three eggs (n = 2 nests). Both sexes incubated; the incubation period was 15–17 d (n = 2 nests). Both male and female participated in brooding and feeding the young, which remained for 3 d in the nest and became independent of their parents at 45 d of age. Based on 194 identified food items, the Sakalava Rail’s diet was composed of invertebrates: spiders (53.1%), insects (32%), crustaceans (10.8%) and molluscs (4.1%). The home ranges of two radio-tagged individuals were 0.95 and 1.98 ha. 相似文献
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Trehalose induces resistance to powdery mildew in wheat 总被引:4,自引:0,他引:4
PH. Reignault A. Cogan J. Muchembled A. Lounes-Hadj Sahraoui R. Durand M. Sancholle 《The New phytologist》2001,149(3):519-529
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Ino?Agrafioti Jonathan?Swire James?Abbott Derek?Huntley Sarah?Butcher Michael?PH?StumpfEmail author 《BMC evolutionary biology》2005,5(1):23