Manetas Y
Laboratory of Plant Physiology, Department of Biology, University of Patras, GR-265 00 Patras, Greece.
New Phytol. 2003 Jun;158(3):503-508. doi: 10.1046/j.1469-8137.2003.00768.x.
• Here the hypothesis was tested that hairs over photosynthetic tissues afford protection against excess radiation. • The hair mat covering the epidermis of photosynthetic stems of Verbascum speciosum was easily removed by mild mechanical treatment. Thus, optical properties and chlorophyll fluorescence parameters were studied in the field in intact and de-haired stems, receiving ambient, ambient minus UV-B, or ambient minus total UV radiation through selective cut-off filters. • Optical analysis indicated that de-hairing exposes underlying tissues to appreciably higher photon fluxes in the UV but slightly higher in the visible part of the spectrum. Under full solar radiation, hair removal resulted in considerable suppression of photosynthetic electron transport rates, yet this negative effect was completely abolished by excluding the UV-B radiation band. • It is concluded that the adverse effects of hair removal on stem photosynthesis of this plant are exclusively due to UV-B radiation. This is the first field confirmation of the protective role of hairs against UV-B radiation damage.
• 在此对光合组织上的毛发能防止过度辐射这一假设进行了验证。
• 毛蕊花光合茎表皮上覆盖的毛毡状毛发可通过温和的机械处理轻易去除。因此，通过选择性截止滤光片，对完整茎和去毛茎在田间进行了光学特性和叶绿素荧光参数的研究，这些茎分别接受环境辐射、环境辐射减去UV - B或环境辐射减去总紫外线辐射。
• 光学分析表明，去毛使下层组织暴露于明显更高的紫外线光子通量中，但在光谱的可见光部分略高。在全太阳辐射下，去除毛发导致光合电子传递速率显著抑制，但通过排除UV - B辐射波段，这种负面影响完全消除。
• 得出结论，去除毛发对该植物茎光合作用的不利影响完全归因于UV - B辐射。这是毛发对UV - B辐射损伤保护作用的首个田间验证。
