Effect of UV radiation and other environmental factors on the liberation of <span style="font-size:14.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";color:black;mso-ansi-language:EN-IN; mso-fareast-language:EN-IN;mso-bidi-language:HI" lang="EN-IN">tetraspores from brown alga <i>Padina boergesenii </i>(Phaeophyta, Dictyotales)</span>

Abstract

50-54<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">Experiments were carried out with tetrasporophytes of Padina boergesenii to understand the effects of ultra violet radiation, light intensity, photoperiod, temperature, salinity and desiccation on the liberation of tetraspores. UV-B radiation inhibits spore liberation while UV-C radiation enhances spore release. UV-A radiation increases spore liberation initially during short time exposure and inhibits spore release during long time exposure. UV-B radiation combined with day light increases the spore liberation. Low illuminance ( 26 <span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:hiddenhorzocr;="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">μEa<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">m-2s-1), short day (8:16 hr LD) and submerged condition of plants and seawater of 35 ppt salinity and 20° C temperature were found to be favourable for maximum liberation of tetraspores. Temperature shock (ranges from 0° C to 50° C up to 120 minutes) could not enhance the spore discharge in Padina boergesenii.</span