Efficience comparee de l'eau transpiree par le maïs, le tournesol et le riz

✍ Scribed by P. Moutonnet; J.-F. Bois

• Publisher: Elsevier Science
• Year: 1982
• Weight: 355 KB
• Volume: 27
• Category: Article
• ISSN: 0002-1571
• DOI: 10.1016/0002-1571(82)90006-1

✦ Synopsis

Several crops were grown in a C23A-type growth chamber with a controlled environment. Photosynthesis (P) and transpiration (T), measured throughout each growth period, were analysed in terms of plant--water transpiration efficiency. The equation submitted by Tanner (1981 ) was used: P/T = K/(e* --e ), where K is a physico/physiologically-based constant and (e*--e) the water vapour pressure deficit. With this formula, we obtained the following average K values: 0.062, 0.044 and 0.025 mbar for maize, sunflower and upland rice, respectively. Furthermore, it was shown with the P/T evaluations throughout the growth periods, that water efficiency changed with plant age; it was a maximum with 40--50-day-old plants.

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