构树叶表皮毛的结构和钾镁离子吸收_毕业论文

毕业论文移动版

毕业论文 > 生物论文 >

构树叶表皮毛的结构和钾镁离子吸收

摘要:利用光学显微镜对构树(Broussonetia papyrifera)叶片表皮毛结构的观察,获得构树叶表皮毛的类型和毛的结构特征及进行叶表皮毛计数,获得构树叶表皮毛的密度数量;进行构树叶表皮毛离子吸收试验,确定构树叶表皮毛是否有离子吸收能力;对构树叶片进行喷水实验,测量其滞水量,确定构树叶片表皮毛对水分的吸附能力。结果表明: 构树的叶表皮有3 种形态显著不同的毛, 包括丝状毛、刺状毛和针状毛,都是由一个细胞组成的。丝状毛有毛囊且较小,呈细长丝状,主要分布于下表皮的叶脉上,且大叶脉的比小叶脉上的要更大更长。刺状毛有毛囊且较大,基部粗大并快速变小呈刺状,且其基部有一圈小刺,多分布于上表皮的叶肉上,上表皮的叶脉上也有部分存在。针状毛无毛囊,极细小呈针状,主要分布于下表皮的叶脉和叶肉上,叶脉上的针状毛的基部不膨大,叶肉上的针状毛的基部膨大。构树叶片下表皮的表皮毛的数量要远大于上表皮。构树叶表皮毛具有离子吸收能力。此外,构树叶片表皮毛还有不错的滞水能力。32734
毕业论文关键词: 表皮毛 ; 桑科 ; 表皮毛 ;离子吸收 ;滞水量
Trichomes structure of the leaves and potassium and magnesium ion absorption
Abstract: Using an optical microscope structure structure of leaf trichomes observed structural characteristics of the leaves to get the type of fur and wool table and leaf trichomes were counted, to obtain the number of the leaves trichomes density; trichomes of the leaves were ion absorption test, trichomes of the leaves to determine whether there is an ion absorption capacity; spraying water on the structure of leaf experiment, stagnant water was measured to determine the structure of leaf trichomes adsorption capacity for water. The results showed that: mulberry leaf epidermis significantly different three forms of hair, including filamentous hair, spiny hairs and needle-shaped bristles are made of a cells. There filamentous hair follicles and small, slender filaments, mainly in the lower epidermis vein, and to larger and longer than the large vein on the small veins. Spiny hairs and hair follicles larger base was thick and fast small spiny, and the base of a small circle of thorns, are located on the upper leaf epidermis, there are some veins present on the epidermis. No needle hair follicles, very small needle-like, mainly in the upper and lower epidermis of the leaf veins, needle-shaped bristles on the base not dilated veins, needle-leaf hairs on base dilated. By structure of leaf trichomes quantity of skin much larger than the epidermis. Trichomes of the leaves have ion absorption capacity. In addition, configuration of leaf trichomes also good water retention capacity.
Keywords: trichomes ; Moraceae ; epidermal hair ; ion absorption ; water holding capacity of
目录
引言    5
1 材料与方法    6
1.1供试材料    6
1.2实验方法    6
2 结果与分析    7
2.1  表皮毛的分布特点    7
2.2  表皮毛的形态结构    9
2.2.1  丝状毛    9
2.2.2  刺状毛    10
2.2.3  针状毛    11
2.3  表皮毛的滞水量    12
2.4  表皮毛的离子吸收能力    12
2.4.1  表皮毛对钾离子的吸收能力    12
2.4.2  表皮毛对镁离子的吸收能力    13
3 讨论    14
致谢    15
参考文献    15
引言
构树(学名Broussonetia papyrifera)别名褚桃等,为落叶乔木,高10 - 20m;树皮暗灰色;小枝密生柔毛。它的树冠呈张开状态,树叶呈卵形或广卵形;树皮较平整且光滑,其颜色为浅灰色或灰褐色,并且不容易开裂,整个植株乳汁丰富。构树为强阳性树种,适应性特强,抗逆性强;具有速生性、适应性强、分布地域广、易繁殖、热量高、轮伐期短等特点,且其根系浅,侧根分布很广,生长速度快,萌芽力和分蘖力强,耐修剪,抗污染能力强[1-2]。构树在中国的温带、热带均有分布,不论是在平原、丘陵或山地都能良好的生长,其叶是一种很好的猪饲料,其韧皮纤文材质洁白,是一种造纸的高级原料,其根、树液和种子均可以入药,总之构树的经济价值很高,很具研究价值。 (责任编辑:qin)