黑鲷三倍体的人工诱导研究

STUDY ON TRIPLOIDY INDUCTION IN THE BLACK PORGY, SPARUS MACROCEPHALUS (BASILEWSKY)

分别于1989年3—6月、1990年3—5月在天津和青岛两地采用冷、热休克法对黑鲷进行三倍体的人工诱导研究。结果表明,冷休克法诱导三倍体的效果好于热休克法,其最适诱导条件为卵子在受精后5min,温度为3—4℃的海水中处理10—20min,三倍体诱导率最高可达50.35％;正交试验证明,三倍体率受冷、热休克法的三因素影响程度的顺序由大到小依次为,处理时间、处理时刻、处理温度;黑鲷染色体数目:2n=48,3n=72,它们的染色体组型也同时获得。

Studies on triploidy induction in the marine commercial fish--the black porgy, Sfarusmacrocephalus (Basilewsky) were carried out using cold- and heat-shock techniques from March to June in 1989 and March to May in 1990 in Tianjin and Qingdao. Results of studies show that the cold-shock technique is more advantageous for inducing triploidy in the black porgy than the heat-shock technique. Under cold-shock treatment, the optimal condition for inducing triploidy in the black porgy was to treat the eggs at 3-4℃, 5 minutes after fertilization for 10-20 minutes. The maximum percentage of occurrence of triploidy was 50.35%. Under heat-shock treatment, the optimal condition for the inducing triploidy was to treat the eggs at 32-35℃, 5 minutes after fertilization for 8 minutes. The maximum percentage of occurrence of triploidy was 36.04%. The orthogonal design results showed that the rate of occurrence of triploidy was affected firstly by treatment duration, secondly by treatment time, and lastly by treatment temperature under both cold-shock and heat-shock treatment.The early stage of triploidy in the black porgy can be identified in the gastrula stage from chromosome spreads. Observation under the microscope revealed 48 chromosomes in diploidy and 72 in triploidy. Karyotypes of diploidy and triploidy were obtained through observation and analysis.This paper also presents the results of observation and analysis of the effect of cold- and heat-shock on the extent of embryo development and on the relationship between fertilization temperature and inducing triploidy.