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991.
Hydrangea bretschneideri Dipp is a highly popular ornamental plant for garden decoration. Genetic engineering
technology has been successfully used in many plant species, but it is limited in Hydrangea. Here we established
an efficient regeneration system by using stem segments as explants for the first time. In our study, the plant
growth regulators (PGRs) were evaluated at the different regeneration processes, including axillary shoots regeneration and root induction. We found that the optimal concentration for axillary buds’ induction was 2.0 mgL−1
6-BA and 0.5 mgL−1
1 IAA, its highest induction rate was 70%. Moreover, the highest axillary shoots proliferation
coefficient was 10.7 on the Murashige and Skoog (MS) medium with 2.0 mgL−1 6-benzyladenine (BA), 0.2 mgL−1
indole-3-butyric acid (IBA), and 1.0 mgL−1 gibberellin A3 (GA3). The highest frequency of root induction was
80.0 ± 0.06% by culturing the elongated shoots in 1/2 MS medium containing 0.1 mgL−1 IBA. In summary,
our study will provide an effective technology for large-scale propagation and important pathway for promoting
the popularization and application of Hydrangea bretschneideri Dipp. 相似文献
992.
993.
Liu Tengfei Sun Liang Meng Qiucheng Yu Jianghui Weng Lushui Li Jinjiang Deng Lihua Zhu Qihong Gu Xingyou Chen Caiyan Teng Sheng Xiao Guoying 《Plant and Soil》2021,463(1-2):39-53
Plant and Soil - Rice accumulates higher levels of cadmium (Cd) in grain than other cereals, and hybrid rice varieties cover around half of the total rice area in China. Therefore, understanding... 相似文献
994.
Journal of Ichthyology - The feeding of burbot Lota lota was studied in the modern conditions of the Kuibyshev Reservoir. With the decrease in the abundance of ruff Gymnocephalus cernuus in the... 相似文献
995.
996.
Li‐Hsuan Ho Yung‐I Lee Shu‐Ying Hsieh I‐Shiuan Lin Yun‐Chien Wu Han‐Yu Ko Patrick A. Klemens H. Ekkehard Neuhaus Yi‐Min Chen Tzu‐Pi Huang Chih‐Hsin Yeh Woei‐Jiun Guo 《Plant, cell & environment》2021,44(1):20-33
Gastrodia elata, a fully mycoheterotrophic orchid without photosynthetic ability, only grows symbiotically with the fungus Armillaria. The mechanism of carbon distribution in this mycoheterotrophy is unknown. We detected high sucrose concentrations in all stages of Gastrodia tubers, suggesting sucrose may be the major sugar transported between fungus and orchid. Thick symplasm‐isolated wall interfaces in colonized and adjacent large cells implied involvement of sucrose importers. Two sucrose transporter (SUT)‐like genes, GeSUT4 and GeSUT3, were identified that were highly expressed in young Armillaria‐colonized tubers. Yeast complementation and isotope tracer experiments confirmed that GeSUT4 functioned as a high‐affinity sucrose‐specific proton‐dependent importer. Plasma‐membrane/tonoplast localization of GeSUT4‐GFP fusions and high RNA expression of GeSUT4 in symbiotic and large cells indicated that GeSUT4 likely functions in active sucrose transport for intercellular allocation and intracellular homeostasis. Transgenic Arabidopsis overexpressing GeSUT4 had larger leaves but were sensitive to excess sucrose and roots were colonized with fewer mutualistic Bacillus, supporting the role of GeSUT4 in regulating sugar allocation. This is not only the first documented carbon import system in a mycoheterotrophic interaction but also highlights the evolutionary importance of sucrose transporters for regulation of carbon flow in all types of plant‐microbe interactions. 相似文献
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