摘 要

本文对紫楠种子的脱水耐性进行了研究，通过测定种子在脱水过程中的生理生化变化，以揭示了紫楠脱水耐性的机理。主要结果如下：

1 成熟的紫楠种子含水量为40.15％，自然脱水到 20%时生活力仅为 8%，表现出顽拗型种子特点。

2 在自然脱水过程，种子相对电导率不断上升，SOD 活性不断下降，POD活性先上升而后急剧下降。MDA 的含量随着含水量的下降而增加。

关键词：紫楠种子；含水量；生活力；脱水耐性

The research of Phoebe sheareriis Seed dehydration tolerance

Abstract

 In this paper, The desiccation tolerance of Phoebe sheareriis seeds were studied, by measuring the physiological and biochemical changes of the seeds in the process of desiccation, to reveal the desiccation tolerance mechanism of Phoebe sheareriis seeds.The main results are showed below:

1. The moisture content of  rippen Phoebe sheareriis seeds is 40.15%; When the moisture content reach 20% by natural dehydration, the vigor of the seeds was 

only 8% and showed the characteristics of recalcitrant seeds.

2. During the process of natural wind drying, the seeds’ electrolytic conductivity 

showed increasing while the SOD (superoxide dismutase ) kept declining. At the same time, the activity of POD firstly rose then declined sharply.  The content of MDA

 declined with the increasing of  the moisture content.

Key words：Phoebe sheareriis seeds，desiccation tolerance,moisture content，vigor

目 录

前言............................................................................................................................ 1

1 文献综述 ......................................................................................................... …..3

1.1 种子脱水耐性 ........................................................................................... …….3

1.1.1 种子脱水耐性的生理生化基础 ...............................................................2

1.1.2 种子自然成熟脱水的生理作用 ...............................................................4

1.1.3种子过度脱水的生理伤害……………………………………………............................5

2 材料与方法 ...........................................................................................................7

2.1 供试种子材料 ..................................................................................................7

2.2 种子脱水耐性研究 ........................................................................................7

2.2.1 种子脱水与生活力测定 ...........................................................................7

2.2.2 相对电导率测定 .....................................................................................7

2.2.3 过氧化物酶（ POD）活性测定 ..............................................................7

2.2.4 超氧化物歧化酶（ SOD）活性测定 .....................................................8

2.2.5 丙二醛（ MDA）含量测定 ................................................................... 8

3 结果与分析 .........................................................................................................10

3.1 紫楠种子的基本形态与生活力测定 ..........................................................10

3.1.1 种子的基本形态 ...................................................................................10

3.1.2 种子生活力测定 ...................................................................................11

3.2 紫楠种子脱水耐性 ......................................................................................12

3.2.1 种子脱水过程生活力的变化 ...............................................................12

3.2.2 种子脱水过程相对电导率的变化 .......................................................13

3.2.3 种子脱水过程 SOD 活性的变化 ........................................................14

3.2.4 种子脱水过程 POD 活性的变化 ..........................................................15

3.2.5 种子脱水过程 MDA 含量的变化 .........................................................16

4 讨论 .......................................................................................................................17

4.1 紫楠种子脱水研究 ......................................................................................17

4.1.1 脱水对种子生活力的影响 .....................................................................17

4.1.2 脱水对种子保护酶系统活性的影响 .....................................................17