[Cumulative effect of solar ultraviolet-B radiation on pollen germination and tube growth of 19 species in vitro].
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) (280-320 nm, 350 and 500 mW/m2 biologically effective UV-B radiation), simulating 8% and 21% stratospheric ozone depletion in Lanzhou, China (36.04 degrees N, 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.
Feng
Huyuan
H
School of Life Sciences, Key State Laboratory of Arid Agroecology, Lanzhou University, Lanzhou 730000. fenghy@lzu.edu.cn
An
Lizhe
L
Tan
Lingling
L
Hou
Zongdong
Z
Wang
Xunling
X
D035264:Flowers / Q000254:growth & development / Q000528:radiation effects*; D018525:Germination; D010944:Plants / Q000528:radiation effects; D011058:Pollen / Q000254:growth & development / Q000528:radiation effects*; D014466:Ultraviolet Rays