School of Life Sciences, Devi Ahilya University, Khandwa Road, Indore 452017, India.
Plant Sci. 2012 Nov;196:85-92. doi: 10.1016/j.plantsci.2012.07.011. Epub 2012 Aug 5.
A field study was conducted to investigate the impact of ambient solar UV on the various growth, physiological and yield parameters of four sorghum (Sorghum bicolor L.) varieties-Indore-12, Indore-26, CSV-23 and Indore-27 by excluding either UV-B (<315 nm) or UV-A/B (<400 nm) components of solar spectrum. Exclusion of UV significantly enhanced plant height, area and specific leaf weight of flag leaf, biomass accumulation, yield parameters and harvest index in all the sorghum varieties. Chlorophyll b was significantly enhanced and chlorophyll a increased to a lesser extent, UV-B absorbing substances and chlorophyll a/b ratio were significantly decreased by the exclusion of solar UV. The enhancement in the vegetative growth and yield by UV exclusion might be linked to the remarkable increase in rate of photosynthesis in sorghum varieties. The magnitude of the response was high in I-26 and I-27 as compared to CSV-23 and I-12 after exclusion of solar UV. All the varieties of sorghum had a negative cumulative stress response index (CSRI), the sensitivity of the sorghum varieties was in the following sequence I-12>CSV-23>I-26>I-27. Thus I-27 was the most sensitive and I-12 the least sensitive variety to present level of solar UV radiation. The differences in UV sensitivity identified among sorghum varieties might be useful in breeding programs for increased tolerance to UV-B radiation.
一项田间研究旨在调查环境太阳紫外线对四种高粱（Sorghum bicolor L.）品种-Indore-12、Indore-26、CSV-23 和 Indore-27 的各种生长、生理和产量参数的影响，方法是排除太阳光谱的 UV-B（<315nm）或 UV-A/B（<400nm）成分。排除 UV 显著提高了所有高粱品种的株高、叶面积和旗叶比叶重、生物量积累、产量参数和收获指数。叶绿素 b 显著增加，叶绿素 a 增加较少，UV-B 吸收物质和叶绿素 a/b 比显著减少。UV 排除对营养生长和产量的促进可能与高粱品种光合作用速率的显著增加有关。与 CSV-23 和 I-12 相比，排除太阳 UV 后，I-26 和 I-27 的响应幅度更高。所有高粱品种的累积胁迫响应指数（CSRI）均为负值，高粱品种的敏感性按以下顺序排列：I-12>CSV-23>I-26>I-27。因此，I-27 对目前水平的太阳 UV 辐射最敏感，而 I-12 最不敏感。高粱品种之间鉴定的 UV 敏感性差异可能有助于培育对 UV-B 辐射具有更高耐受性的品种。
