A study of the total ultraviolet exposure to all the leaves for small-plant growth

✍ Scribed by A.V. Parisi; J.C.F. Wong; V.J. Galea

• Book ID: 104373363
• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 722 KB
• Volume: 45
• Category: Article
• ISSN: 1011-1344
• DOI: 10.1016/s1011-1344(98)00157-2

✦ Synopsis

A dosimetric spectrum evaluator has been employed to evaluate the total biologically effective UV (UVBE,,,,,,) incident on the surface of all the leaves of small plants. It is applied to evaluate the UVBE,,,,, to soybean leaves (Glycine mu [L.] Merr.), cultivar Essex. The plants receive three levels of UVBE,,,,, averaged over all the leaves (0,8.1 and 15.8 J cm-') from emergence to the V7 growth stage. As canopy closure occurs with plant growth, the ratio of the average of the UVBl&,,, to all leaves compared to that on the uppermost set of leaves changes from 0.85 to 0.50 to 0.29 for the V2, V4 and V7 stages, respectively. Measurement of the UVBE,,,, at the top of the canopy will introduce errors of 18, 100 and 245% at the V2, V4 and V7 stages, respectively, compared to the actual exposure to the plant leaves. The evaluation of leaf UVBE,,,,, allows formulation of models defining plant response, such as suppression of plant height and leaf area in terms of the UV exposure to all the leaves along with the effects on the fresh and dry weights of the leaves, stems and roots.