摘要
微观繁殖体在越冬和度夏等恶劣环境下可作为绿潮的“种子库”,待到环境条件适宜时快速生长繁殖,成为绿潮早期暴发的重要种子来源。选取由微观繁殖体发育而来的浒苔幼苗为实验材料,在室外自然光照条件下,设置2个光照强度水平(低光强:LL;高光强:HL)和3个盐度梯度(LS:12;MS:22;HS:32),分析6个处理组合对浒苔微观繁殖体幼苗生长和光合生理的影响。结果显示:光照强度、盐度及二者交互作用显著影响浒苔幼苗的相对生长速率(RGR)和最大净光合速率(P_(m))(p<0.05),在低光强(LL)、盐度适当降低(MS)条件下,藻体的RGR和Pm最高。光响应曲线(P—I曲线)显示,不同处理下浒苔幼苗的净光合速率(P)随着光照强度增加而逐渐增加,未出现明显的光抑制,表明浒苔幼苗对高光强的耐受性很强。进一步荧光参数分析显示:光照强度、盐度及二者交互作用对浒苔幼苗的最大相对电子传递速率(rETRmax)存在显著影响(p<0.05),低光强(LL)、盐度适当降低(MS)有利于提高其rETR_(max)。此外,光照强度、盐度及二者交互作用对浒苔幼苗的光合色素质量分数具有显著影响(p<0.05)。在同一光照强度条件下,叶绿素a(Chl a)和叶绿素b(Chl b)质量分数随着盐度增加而呈现出先下降后升高的趋势,在MS处理组最低;同一盐度条件下,HL处理组的Chl a和Chl b质量分数显著高于LL处理组(p<0.05)。结果表明,低光强条件下,盐度的适当降低促进了浒苔微观繁殖体幼苗的生长。因此,浒苔绿潮早期暴发规模的大小,一定程度上取决于光照强度与海水盐度的变化及耦合作用。
As the“seed bank”of green tide in harsh environments such as overwintering and oversummering,micropropagules grow and reproduce rapidly when the environmental conditions are suitable,becoming an important seed source for the early-stage outbreak of green tide.In this study,the micropropagule seedlings of Ulva prolifera were collected as experimental materials,and two light intensity levels(lower light intensity:LL;higher light intensity:HL)and three salinity gradients(lower salinity,LS:12;medium salinity,MS:22;higher salinity,HS:32)were set to analyze the effects of 6 different treatment combinations on the growth and photophysiology of micropropagule seedlings in Ulva prolifera.The results showed that light intensity,salinity and their interaction had significant effects on the relative growth rates(RGR)and maximum net photosynthetic rates(P_(m))of U.prolifera seedlings(p<0.05).The maximum values of RGR and Pmoccurred at LL and MS.Light response curve(P—I curve)suggested that the net photosynthetic rates(P)of U.prolifera seedlings increased with the light intensity increment under different conditions,showed no significant photoinhibition after saturation light intensity(Ik),indicating the great tolerance of U.prolifera seedlings to the high light intensity.Further fluorescence parameters showed that salinity and their interaction had significant effects on the maximum relative electrons transfer rate(rETR_(max))(p<0.05),LL and MS were beneficial to improve the rETRmax.Furthermore,light intensity,salinity and their interaction had significant effect on the photosynthetic pigments of U.prolifera seedlings(p<0.05).Under the same light intensity condition,the contents of chlorophyll a(Chl a)and chlorophyll b(Chl b)firstly decreased and then increased with the salinity increment(p<0.05).Under the same salinity condition,the contents of Chl a and Chl b under HL treatment were significantly higher than those under LL treatment(p<0.05).Our findings suggested that LL and MS significantly promoted the growth of U.prolifera micropropagule seedlings.Therefore,the scale of the early-stage outbreak of U.prolifera green tide may potentially depend on the changes of light intensity,seawater surface salinity and their coupling effects.
作者
王津果
陈泽宇
倪嘉璇
何昊林
周伟
WANG Jinguo;CHEN Zeyu;NI Jiaxuan;HE Haolin;ZHOU Wei(Jiangsu Key Laboratory of Marine Bioresources and Environment,Ministry of Natural Resources,Jiangsu Ocean University,Lianyungang 222005,China;Co-innovation Center of Jiangsu Marine Bio-industry Technology,Ministry of Natural Resources,Jiangsu Ocean University,Lianyungang 222005,China;Jiangsu Key Laboratory of Marine Biotechnology,Ministry of Natural Resources,Jiangsu Ocean University,Lianyungang 222005,China;Key Laboratory of Coastal Salt Marsh Ecosystems and Resources,Ministry of Natural Resources,Jiangsu Ocean University,Lianyungang 222005,China)
出处
《江苏海洋大学学报（自然科学版）》
CAS
2022年第4期1-10,共10页
Journal of Jiangsu Ocean University:Natural Science Edition
基金
江苏省自然资源发展专项资金项目(JSZRHYKJ202107)
江苏省基础研究计划自然科学基金面上项目(BK20221398)
江苏省政策引导类计划(苏北科技专项)(SZ-LYG202036)
江苏省产学研合作项目(BY2021356)
江苏海洋大学人才引进科研基金项目(KQ19068)
连云港市“花果山英才计划”—双创博士项目(KK21054)
江苏省优势学科建设工程资助项目。
关键词
浒苔微观繁殖体
光照强度
盐度
生长
光合生理
绿潮
Ulva prolifera micropropagules
light intensity
salinity
growth
photophysiology
green tide
