多球果型马尾松的形态和生殖生物学特征研究

本文对多球果型马尾松和常见型马尾松在生长状态、形态结构、生殖发育等方面的差异进行研究和分析.在多球果型马尾松雌性生殖枝上,能够着生40～80个球果(大孢子叶球),有的甚至可以达到193个以上.而在常见型马尾松的雌性生殖枝上, 通常只着生有1～8个球果,最常见的是着生2～4个球果.多球果型马尾松和常见型马尾松在雌球花的芽组织结构和雌球花的分化过程中有着明显的差异.通过显微分析我们发现:多球果型马尾松雌球花原基的发育在当年生过冬顶芽的下部,在它的上部,还发育有一系列的营养芽原基(10列以上).而常见型马尾松雌球花原基的发育在当年生过冬顶芽的顶端.雌球花发育机理的不同,决定了多球果型马尾松球果的着生部位发生了变异.多球果型马尾松球果着生在春梢的下(基)部,常见型马尾松球果着生在春梢的顶部.多球果型马尾松与常见型马尾松球果(大孢子叶球)的发育过程和发育起始时间不相同.通过对8～12月标本进行显微切片分析,多球果型马尾松球果的发育起始时间在当年的8月(过冬顶芽开始形成的同时),与小孢子叶球的发育起始时间同步.常见型马尾松球果的发育起始时间是当年的11月,两种类型马尾松的大孢子叶球都是在次年4月受粉,到第三年的11月种子成熟.多球果型马尾松球果比常见型马尾松球果多3个月的发育时间.多球果型马尾松个体大量的长串状多球果性状在历年都能重复出现,这说明该性状具有个体水平的稳定性.无性繁殖研究证明,多球果型马尾松的长串状多球果性状,可以通过嫩枝嫁接的方式,进行性状的传递.对多球果型马尾松进行有性繁殖研究时我们发现,多球果型马尾松的球果可以发育出种子,且成熟种子的发芽率为60%～76%.这说明多球果型马尾松与常见型马尾松一样,可以用种子进行后代繁殖.多球果型马尾松与常见型马尾松在形态和生长速率方面没有明显差异.

Morphology and Reproduction Analysis of a Novel Genotype of Pinus massoniana Polycone

Study of Characters in Shape and Procreation Biology ofMultiple Cone type Pinus Massoniana LameAbstract This article is to research and analyze the differences of the state of growth?shape structure?procreation development between the multiple cone type Pinus massoniana Lame and the common type Pinus massoniana Lame. On the female procreation branch of the multiple cone type Pinus massoniana Lame,it can produce 40~80 cones,even up to or over 193 ones .However, on the female procreation branch of the common type Pinus massoniana Lame , the common number is 2~4. There exists obvious differences in the tissue structure of the buds and in the disintegration process, in the female cone flowers of Pinus massoniana Lamb between the multiple cone type and the common type .Through the microscope analysis, we can find: the anlagen of the female cone flower of the multiple cone type often grows from the bottom of the top bud that grows in that year's winter ,on the top of thetop bud,there exists a series of anlagen of the nutrition bud too(more than 10 lines).However, the anlagen of the female cone flower of the common type often grows from the top of the top bud that grows in that year's winter .The aberrance of the growth parts of the multiple cone type's cones depends on the difference of the growth mechanism of the female flower .The cones of the multiple cone type often originate from the bottom of the tip of a branch in spring, however, the common type's cones often originate from the top.The development process and starting time of the cones between the multiple cone type and the common type are different .Through the analysis of microscope section from 8~12 month specimen ,the cone's development starting time of the multiple cone type is often on August in that year,in synchronization with the microspore leave ball .comparatively ,the development starting time of the common type's cones is often on November .Both kinds of megaspore leave ball of Pinus massoniana Lame are pollinated in next year ,and the seeds are often mature on November in the third year .The development time of the multiple cone type is three months longer than that of the common type. The character of a lot of long string cones of the multiple cone type Pinus massoniana Lame appears frequently every year ,which indicates that the property has a stability at individual level. The researches of the agamogenesis prove the property of long string cone can be transmitted in the way of wand's inoculation. From the researches of the sex reproduction of the multiple cone type ,we can find that the cones of the multiple cone type can produce seeds and the pullulating percentage is from 60 to 76 .This indicates that the multiple cone type Pinus massoniana Lame can be reproduced by seeds as the common type do. There are no obvious differences in the shape and the growth speed between the multiple cone type and the common type Pinus massoniana Lame.