Abstract

Root-hair growth and development regulated by soil microbes is associated with auxin. In this background, we hypothesized that mycorrhizal fungal inoculation induces greater root-hair growth through stimulated auxin synthesis and transport under water stress conditions. Trifoliate orange (Poncirus trifoliata) was inoculated with an arbuscular mycorrhizal (AM) fungus (Funneliformis mosseae) under well-watered (WW) and drought stress (DS) for 9 weeks. Compared with non-AM seedlings, AM seedlings displayed significantly higher density, length, and diameter of root hairs and root indoleacetic acid (IAA) level, whereas lower total root IAA efflux, regardless of soil moisture status. Root PtYUC3 and PtYUC8 involved in IAA biosynthesis were up-regulated by mycorrhization under WW and DS, whereas AM-modulated expression in PtTAA1, PtTAR2, PtYUC4, and PtYUC6 depended on status of soil moisture. Mycorrhizal inoculation down-regulated the transcript level of root auxin efflux carriers like PtPIN1 and PtPIN3, whereas significantly up-regulated the expression of root auxin-species influx carriers like PtABCB19 and PtLAX2 under DS. These results indicated that AMF-stimulated greater root-hair growth of trifoliate orange under DS that is independent on AMF species is related with mycorrhiza-modulated auxin synthesis and transport, which benefits the host plant to enhance drought tolerance.

Details

Title
Mycorrhiza stimulates root-hair growth and IAA synthesis and transport in trifoliate orange under drought stress
Author
Chun-Yan, Liu 1 ; Zhang, Fei 1 ; De-Jian, Zhang 1 ; Srivastava, A K 2 ; Qiang-Sheng, Wu 3 ; Ying-Ning Zou 1 

 College of Horticulture and Gardening, Yangtze University, Jingzhou, Hubei, China; Institute of Root Biology, Yangtze University, Jingzhou, Hubei, China 
 ICAR-Central Citrus Research Institute, Amravati Road, Nagpur, Maharashtra, India 
 College of Horticulture and Gardening, Yangtze University, Jingzhou, Hubei, China; Institute of Root Biology, Yangtze University, Jingzhou, Hubei, China; Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic 
Pages
1-9
Publication year
2018
Publication date
Jan 2018
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
1992989745
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.