（毕业设计论文）《三峡紫皮大蒜和百合大蒜染色体核型的比较分析》.docVIP

毕业设计（论文） 题目 学生姓名 学号 专 业 生物科学 班级 指导教师 评阅教师 完成日期 20年 月 Student：WangYuan Instructor：Chuanhua Wang AbstractThis study mainly study the seed characterristics and photosynthetic characteristics of Platycarya strobilacea of Juglandaceae Platycaryapollenites,we obtain a lot of valuable conclusion.(1)Thousand-grain weight,percentage of germination,viability of Platycarya strobilacea.We analyzed the results and methods and had an initial understanding of Seed characteristic of Platycarya strobilacea.During the research,we found that ,the seed of Platycarya strobilacea has dormancy.When we use sand harboring,6-BA,NAA and GA-3 to treat the seeds,we found that GA-3 can release the dormancy of the seeds,but sand harboring,6-BA and NAA dont work.(2)We researched the photosynthetic characteristics of Platycarya strobilacea under four controlled light regimes(3%,6%,12% and 25% natural irradiance and tow nitrogen concentration(15mmol/l and 3mmol/l). The characteristic parameters of light response curve was fitted by non-rectangle hyperbola model.Simulation results show that the maximum photosythesis rate Amax will increase when light regimes increase,but different nitrogen concentration doest have remarkable effect on the maximum photosythesis rate Amax.The dark respiratory rate Rd reach the maximum when the light regime is 12%,but the dark respiratory rate is on a declining curve when light regime is 25%.Different nitrogen concentration still doest have remarkable effect on dark respiratory rate. Key Words:Platycarya strobilacea; seed characterristics; seed dormancy; photosynthetic characteristics;non-rectangle hyperbola model 前言 化香[Platycarya strobilacea Sieb.et Zucc.]为胡桃科落叶灌木和小乔木，高可达20m，基数羽状复叶，小叶7-23片，卵状披针形，基部歪斜.夏季开花，茅荑花序直立。果实10月成熟，果序圆柱形，有细鳞片，松球状。坚果小，两侧具窄翅，种子数量较多，可用种子繁殖【1,2】。化香在我国分布面积广，产于黄河流域及以南地区，如：皖、豫、苏、浙赣、鄂、奥、桂、滇、黔等地广泛分布 ,朝鲜、日本也有。最喜光 ,耐干早痔薄 ,低山、丘陵习见【1,2】,城郊山 区居多 如在武当山海拔800～1300m的落叶阔叶林地带有大片分布 ,树高 15～20m,胸径20～30cm,长势良好【1,2】。 化香一