| 摘要: |
| 为探讨生长素对黑木相思 Acacia melanoxylon 组培苗不定根的诱导效果, 提升其工厂化育苗的
生产效率, 以黑木相思良种 SR14 组培苗丛芽为材料, 以 1 / 2 改良 MS 为基本培养基, 分别添加低 (0. 3
mg·L
-1
)、 中 (0. 9 mg·L
-1
)、 高 (1. 5 mg·L
-1
) 浓度的吲哚乙酸 ( IAA)、 吲哚丁酸 ( IBA)、 2, 4-
二氯苯氧乙酸 (2, 4-D)、 α-萘乙酸 (NAA) 和生根粉 (ABT-1), 培养 30 d 后, 统计不定根的数量、
长度等生长指标, 比较不同生长素或生长素类似物对 SR14 生根诱导的影响; 并对优选出的 IAA 和
ABT-1 分别设置 5 个浓度梯度, 进行单一使用时最佳浓度的筛选; 然后, 将最佳浓度的 IAA 和
ABT-1 分别与低、 中、 高浓度的 IBA 或 NAA 组合使用, 比较其对 SR14 的生根诱导效果。 结果得出, 单独
使用 1. 5 mg·L
-1
IAA 诱导 SR14 不定根时生根率最高 (78. 31%), 单独使用 2. 7 mg·L
-1 ABT-1 的诱导效
果次之 (65. 97%); 组合使用两种生长素或生长素类似物诱导 SR14 不定根的效果优于单一种类, 其中 2. 7
mg·L
-1 ABT-1+1. 5 mg·L
-1
IBA 诱导 SR14 不定根的生根率最高 (82. 00%), 平均生根数最多 (6. 28 条),
而 2. 7 mg·L
-1 ABT-1+0. 9 mg·L
-1
IBA 诱导时平均根最长 (12. 33 cm); 形态学观察表明, 不定根形成于
茎基部切口处褐化组织上方, 逐渐发育为 “奶嘴” 状结构并最终伸长形成根系。 研究优化了黑木相思 SR14
无性系不定根的诱导条件, 明确了生长素种类、 浓度及配比对黑木相思组培苗不定根诱导的影响。 |
| 关键词: 黑木相思 组织培养 生根诱导 生长素 条件优化 |
| DOI： |
| 分类号: |
| 基金项目:国家重点研发计划子课题 (2022YFD2200205-1)。 |
|
| Effects of Auxin Types and Concentrations on the Induction of Adventitious Roots in Acacia melanoxylon Tissue-cultured Seedlings |
|
Zhang Zhiwei1, Hu Bing2, Chen Jinhui1, Zeng Bingshan3, Lu Zhaohua4
|
|
1.College of Tropical Crops Hainan University;2.Research Institute of Tropical Forestry, Chinese Academy of Forestry,;3.Research Institute of Tropical Forestry, Chinese Academy of Forestry;4.Research Institute of Tropical Forestry, Chinese Academy of Forestry
|
| Abstract: |
| To investigate the induction effects of auxin on adventitious roots in Acacia melanoxylon tissuecultured seedlings and to improve the production efficiency of its industrialized seedling propagation, the cluster shoots of the superior A. melanoxylon clone SR14 tissue -cultured seedlings were used as materials. With 1 / 2
modified MS as the basal medium, low (0. 3 mg·L
-1
), medium (0. 9 mg·L
-1
), and high (1. 5 mg·
L
-1
) concentrations of indole-3-acetic acid (IAA), indole-3-butyric acid ( IBA), 2, 4-dichlorophenoxyacetic acid (2, 4-D), α-naphthaleneacetic acid (NAA), and rooting powder (ABT-1) were added respectively. After 30 days of culture, growth indicators such as the number and length of adventitious roots were statistically analyzed to compare the effects of different auxins or auxin analogues on the rooting induction of SR14.
For the selected IAA and ABT-1, five concentration gradients were set up respectively to screen the optimal
concentration for single use. Then, the optimal concentrations of IAA and ABT-1 were combined with low,
medium, and high concentrations of IBA or NAA, respectively, to compare their effects on the rooting induction of SR14. The results showed that when 1. 5 mg·L
-1
IAA was used alone, the rooting rate of adventitious
roots in SR14 was the highest (78. 31%), followed by 2. 7 mg·L
-1 ABT-1 (65. 97%). The effect of combining two auxins or auxin analogues on inducing adventitious roots in SR14 was better than that of a single kind.
Among the combinations, 2. 7 mg · L
-1 ABT - 1 + 1. 5 mg · L
-1
IBA resulted in the highest rooting rate
(82. 00%) and the largest average number of roots (6. 28), while 2. 7 mg·L
-1 ABT-1+0. 9 mg·L
-1
IBA induced the longest average root length (12. 33 cm). Morphological observations showed that adventitious roots
formed above the browned tissue at the basal cut of the stem, gradually developed into a "nipple-like" structure
and eventually elongated into a root. This study optimized the induction conditions for adventitious roots in the
A. melanoxylon SR14 clone, and clarified the effects of auxin types, concentrations, and combinations on the
induction of adventitious roots in A. melanoxylon tissue-cultured seedlings. |
| Key words: Acacia melanoxylon tissue culture rooting induction auxin condition optimization |
