Cumulative effect of solar ultraviolet-B radiation on pollen germination and tube growth of 19 species in vitro
Feng, H.; An, L.; Tan, L.; Hou, Z.; Wang, X.
Ying Yong Sheng Tai Xue Bao 13(7): 814-818
2002
ISSN/ISBN: 1001-9332 PMID: 12385209 Document Number: 550528
In order to determine the response of pollen to UV-B irradiation and the cumulative effects of UV-B exposure time on pollen germination and tube growth of plants, 19 species were investigated in vitro by exposing their pollen grains to two levels of enhanced ultravioet-B(UV-BBE) (280apprx320 nm, 350 and 500 mW/m2 biologically effective UV-B radiation), simulating 8% and 21% stratospheric ozone depletion in Lanzhou, China (36.04degreeN, 1550 m), and to no UV-B (control group). Compared with the control, enhanced UV-B radiation significantly inhibited pollen germination and tube growth in most species. Higher UV-B flux rate caused greater inhibitory effect than lower UV-B radiation level. Several test plants exhibited insensitivity, even stimulation of pollen germination and tube growth to UV-B. The reduction in pollen germination rate and tube growth increased with exposure time, which indicated a cumulative effect of UV-B radiation. It is concluded that changes in pollen susceptibility to UV-B would have a serious ecological consequence under natural conditions.