新疆不同生境下醉马草种子萌发特性及表型特征研究
发布时间：2018-07-16 19:43
【摘要】：草原毒害草的肆意蔓延,使草原生态急速恶化,不但严重影响了当地农牧民的收入和畜牧业的发展,而且也导致草地的进一步退化,所以对草原毒害草地的防控势在必行,而明确自然状态下毒害草种群扩繁更新机制对于其防控十分重要。研究以天山北坡分布最为广泛的草原毒草-醉马草为研究对象,一方面采用常规培养皿纸上发芽法,通过设置不同萌发条件,如温度、光照、水分等,探讨不同生境条件下醉马草种子萌发特征的异同及其响应规律;另一方面采用野外常规取样,通过对醉马草种群株高、株丛径、分蘖数、构件生物量及其分配等指标的测定,探讨不同生境条件下醉马草外观表型特征的差异及其变化,继而为醉马草种群扩繁机制的揭示、综合防控和资源开发提供有力依据。主要研究结果如下:(1)不同生境下新疆醉马草种子的发芽率、发芽指数、发芽势、胚芽长和胚根存在一定的差异性。与全光照相比,恒温条件下黑暗处理明显提高了醉马草的发芽势、发芽率、胚芽长及发芽指数(P0.05),且25℃时萌发最佳,发芽势、发芽率、发芽指数平均依次为73.6%、92.3%、8.2。无论光照与否,10/20℃下4份醉马草种子的发芽率、胚根长、胚芽长、发芽指数都明显高于5/20℃(P0.05)。随海拔升高,醉马草种子发芽势、发芽率、发芽指数呈降低趋势,而胚芽长及胚根长则相关不显著(P0.05)。(2)低浓度PEG(5%~10%)可促进醉马草种子的发芽,高浓度PEG(15%)则会抑制醉马草种子发芽势、活力指数、发芽指数、胚芽长,促进胚根的生长;PEG胁迫下不同来源的醉马草种子发芽率、发芽指数、发芽势间差异显著(P0.05),且高海拔地区(2287 m)的醉马草抗旱性低于中低海拔地区(1650~1832 m)。(3)随海拔增加,醉马草单株生殖枝数、花或果实重、株高呈降低趋势;不同生境间醉马草的地下生物量、根系长度差异不显著(P0.05),依次为37.5 g/株~92.1 g/株、6.6 cm~7.9 cm;地上生物量6月材料A4显著高于材料A6、A5,7月材料A5显著高于材料A6、A4(P0.05),而其长轴长、短轴长及冠幅面积仅在7月显著差异(P0.05),且材料A5显著低于材料A4、A6(P0.05)。(4)从地上构件生物量看,6月,不同生境间醉马草茎重差异不显著(P0.05),叶重材料A4显著高于材料A5、A6;7月,材料A5茎重显著高于材料A6、A4(P0.05),而叶重则差异不显著(P0.05);低海拔材料花或果实重显著高于高海拔区域(P0.05)。生物量分配看,醉马草将生物量向叶、茎、花或果实的分配比例呈降低趋势,依次为48.2%~80.2%、13.5%~30.0%、0.7%~21.8%,且不同生境间表现并不一致;茎分配比例仅在7月表现为材料A5显著高于材料A6、A4(P0.05);6月~7月材料A4、A6的叶分配比例显著高于材料A5(P0.05),而材料A5、A6的花或果实分配比例高于材料A4。
[Abstract]:The wanton spread of the poisonous grass in the grasslands has caused the rapid deterioration of the grassland ecology, which not only seriously affected the income of the local farmers and herdsmen and the development of animal husbandry, but also led to the further degradation of the grassland, so it is imperative to prevent and control the grassland poisoning the grassland. It is very important to define the mechanism of populating and renewing poisonous grass population under natural condition. In this study, the most widely distributed steppe poison grass on the north slope of Tianshan Mountain, the Daphnia sinensis, was studied. On the one hand, by setting different germinating conditions, such as temperature, light, moisture and so on, the method of germinating on common petri dish paper was used. The differences and similarities of seed germination characteristics and their responses in different habitats were discussed. On the other hand, the plant height, cluster diameter, tiller number, component biomass and their allocation were measured by conventional sampling in the field. To explore the differences and changes of phenotypic characteristics of Elaeagnus chinensis under different habitat conditions, and then to provide a powerful basis for revealing the mechanism of population propagation, comprehensive prevention and control and resource development. The main results were as follows: (1) there were some differences in germination rate, germination index, germinating potential, germ length and radicle under different habitats. Compared with the total light, the germination potential, germination rate, germ length and germination index (P0.05) were significantly increased under the condition of constant temperature, and the best germination at 25 鈩，
本文编号：2127472
[Abstract]:The wanton spread of the poisonous grass in the grasslands has caused the rapid deterioration of the grassland ecology, which not only seriously affected the income of the local farmers and herdsmen and the development of animal husbandry, but also led to the further degradation of the grassland, so it is imperative to prevent and control the grassland poisoning the grassland. It is very important to define the mechanism of populating and renewing poisonous grass population under natural condition. In this study, the most widely distributed steppe poison grass on the north slope of Tianshan Mountain, the Daphnia sinensis, was studied. On the one hand, by setting different germinating conditions, such as temperature, light, moisture and so on, the method of germinating on common petri dish paper was used. The differences and similarities of seed germination characteristics and their responses in different habitats were discussed. On the other hand, the plant height, cluster diameter, tiller number, component biomass and their allocation were measured by conventional sampling in the field. To explore the differences and changes of phenotypic characteristics of Elaeagnus chinensis under different habitat conditions, and then to provide a powerful basis for revealing the mechanism of population propagation, comprehensive prevention and control and resource development. The main results were as follows: (1) there were some differences in germination rate, germination index, germinating potential, germ length and radicle under different habitats. Compared with the total light, the germination potential, germination rate, germ length and germination index (P0.05) were significantly increased under the condition of constant temperature, and the best germination at 25 鈩，
本文编号：2127472
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