Embryo of lilacs (Syringa L) culture in vitro and the rapid propagation were studied. The orthogonal experiments, in-cluding the selection of basal medium, embryo age and other factors such as sugar, benzyladenine (BA), naphthalene acetic acid (NAA) and glutamine (Gln), were carried out. The results indicated that the optimal medium for embryo culture was Monnier medium supplemented with NAA (0.001 mgL-1), BA (0.1 mgL-1), sugar (50 gL-1), and Gln (400 mgL-1), with a germination rate of 91.7% at least; the optimal embryo age was 50 d; and Gln had significant effects on the germination rate of embryo. Moreover, the optimal medium for subculture was MS+BA (2 mgL-1)+NAA (0.001 mgL-1)+Gln (0.5 mgL-1), with the propaga-tion coefficient of 3.6 at least.
在温度(25±1)℃,RH65%～75%条件下,对国槐尺蠖Semiothisa cinerearia Bremer et Grey各龄幼虫分别采用0:24、10:14、12:12、14:10、1:85种光周期处理。结果表明,以14:10处理的国槐尺蠖1～5龄幼虫历期最短;以16:8处理的幼虫发育历期最短,且随着光照时间的增加,幼虫发育历期逐渐缩短;不同光周期对于6～7龄幼虫存在显著的影响,但是对于1～5龄影响不大。成虫53%～56%在夜间羽化,越冬蛹在8～14h光照范围内,随光照长度增加发育历期延长,在14～16h光照范围内,历期随光照延长而缩短。以0:24处理的蛹羽化率最高,发育历期最短。
Picea mongolica is an endemic and endangered species in China. Ecosystem made of Picea mongolica is a special sandy forest ecosystem in China. It is found at ecotone between forest and steppe, or agricultural district and pastoral area. Based on investigation, this paper discussed the formation and distribution of Picea mongolica and studied its nature according to ecotone theory. It is clarified that Picea mongolica belongs to Picea meyeri series. That is to say, it became a local race through long-term adaptation to the local climate, then formed allopatric semi-species, and finally turned into a taxonomical species. Picea mongolica forest is a super zonal climax community developing in ecotone between forest zone and steppe zone.
