A neglected alliance in battles against parasitic plants: arbuscular mycorrhizal and rhizobial symbioses alleviate damage to a legume host by root hemiparasitic <i>Pedicularis</i> species

Lin

et al. 2020

IJMS

Plants are associated with hundreds of thousands of microbes that are present outside on the surfaces or colonizing inside plant organs, such as leaves and roots. Plant-associated microbiota plays a vital role in regulating various biological processes and affects a wide range of traits involved in plant growth and development, as well as plant responses to adverse environmental conditions. An increasing number of studies have illustrated the important role of microbiota in crop plant growth and environmental stress resistance, which overall assists agricultural sustainability. Beneficial bacteria and fungi have been isolated and applied, which show potential applications in the improvement of agricultural technologies, as well as plant growth promotion and stress resistance, which all lead to enhanced crop yields. The symbioses of arbuscular mycorrhizal fungi, rhizobia and Frankia species with their host plants have been intensively studied to provide mechanistic insights into the mutual beneficial relationship of plant–microbe interactions. With the advances in second generation sequencing and omic technologies, a number of important mechanisms underlying plant–microbe interactions have been unraveled. However, the associations of microbes with their host plants are more complicated than expected, and many questions remain without proper answers. These include the influence of microbiota on the allelochemical effect caused by one plant upon another via the production of chemical compounds, or how the monoculture of crops influences their rhizosphere microbial community and diversity, which in turn affects the crop growth and responses to environmental stresses. In this review, first, we systematically illustrate the impacts of beneficial microbiota, particularly beneficial bacteria and fungi on crop plant growth and development and, then, discuss the correlations between the beneficial microbiota and their host plants. Finally, we provide some perspectives for future studies on plant–microbe interactions.

Section: Plant Growth-promoting Bacteriamentioning

confidence: 99%

Section: Plant Growth-promoting Bacteriamentioning

confidence: 99%

Research Advances of Beneficial Microbiota Associated with Crop Plants

Lin

et al. 2020

IJMS

“…Additionally, studies of Cuscuta have shown that the functional haustorium transfers macromolecules such as mRNAs, proteins, secondary metabolites and small RNAs, as well as pathogens such as phytoplasma and viruses (Kim & Westwood, 2015;Shahid et al, 2018). Although growth stimulation after attachment to a host has been observed in several facultative parasites (Klaren & Janssen, 1978;Sui et al, 2019), changes in parasites before and after attachment to a host have rarely been experimentally tested (Li et al, 2012). The microscopic structures of haustoria have been the focus of investigation in root hemiparasites (Zhang et al, 2012), whereas investigations of microscopic structures of leaves and stems have received comparatively little attention.…”

Section: Introductionmentioning

confidence: 99%

The changes of morphological and physiological characteristics in hemiparasiticMonochasma savatieribefore and after attachment to the host plant

Chen

Zhu

et al. 2020

PeerJ

Background Monochasma savatieri is an endangered hemiparasitic medicinal plant with a variety of antioxidant, antimicrobial and anti-inflammatory properties. Despite the urgent need to understand the parasitic biology of M. savatieri, parasite-host associations have long been neglected in studies of M. savatieri. Methods We conducted a pot cultivation experiment to analyze changes in the growth traits, physiological performance and anatomical structures of M. savatieri grown with the potential host Gardenia jasminoides E., before and after the establishment of the parasite-host association. Results Prior to the establishment of the parasite-host association, the presence of the host had no significant effect on the maximum root length, leaf indexes or total dry weight of M. savatieri seedlings, but had significant positive effect on seedling height, number of roots or number of haustoria. When it was continuously grown without a host, M. savatieri growth was rather slow. The establishment of the parasite-host association enhanced the growth of M. savatieri, and higher levels of photosynthetic pigments, increased antioxidant enzyme activity and lower malondialdehyde accumulation were observed in M. savatieri with an established parasite-host association. Furthermore, an analysis of the anatomical structures of M. savatieri showed that the establishment of the parasite-host association enabled better development of the seedling vegetative organs than that in seedlings without parasite-host associations. Conclusions Our study demonstrates the physiological and anatomical changes that occurred in M. savatieri after connection with a host and suggests that the enhanced growth and development of M. savatieri were highly dependent on the parasite-host association.

Plant Cell & Environment

“…Plants are engaged with a wide range of beneficial fungi that provide plant with various benefits, for instance, enhanced root system growth (Sukumar et al, ; Zhang et al, ), increased water and nutrient uptake (Almario et al, ; Ezawa & Saito, ), and better stress tolerance (Sui, Zhang, Tian, Xue, & Li, ) in exchange for photoassimilates. Root beneficial fungi have also been demonstrated to influence the timing of important developmental transitions, especially flowering (Das et al, ;Pan et al, ; Zavala‐Gonzalez et al, ).…”

Section: Introductionmentioning

confidence: 99%

Flowering‐mediated root‐fungus symbiosis loss is related to jasmonate‐dependent root soluble sugar deprivation

Zhang

Yuan

Cheng

et al. 2019

The role of flowering in root-fungal symbiosis is not well understood. Because flowering and fungal symbionts are supported by carbohydrates, we hypothesized that flowering modulates root-beneficial fungal associations through alterations in carbohydrate metabolism and transport. We monitored fungal colonization and soluble sugars in the roots of Arabidopsis thaliana following inoculation with a mutualistic fungus Phomopsis liquidambari across different plant developmental stages. Jasmonate signalling of wild-type plants, sugar transport, and root invertase of wild-type and jasmonate-insensitive plants were exploited to assess whether and how jasmonate-dependent sugar dynamics are involved in flowering-mediated fungal colonization alterations. We found that flowering restricts root-fungal colonization and activates root jasmonate signalling upon fungal inoculation. Jasmonates reduce the constitutive and fungus-induced accumulation of root glucose and fructose at the flowering stage. Further experiments with sugar transport and metabolism mutant lines revealed that root glucose and fructose positively influence fungal colonization. Diurnal, jasmonate-dependent inhibitions of sugar transport and soluble invertase activity were identified as likely mechanisms for flowering-mediated root sugar depletion upon fungal inoculation. Collectively, our results reveal that flowering drives root-fungus cooperation loss, which is related to jasmonate-dependent root soluble sugar depletion. Limiting the spread of root-fungal colonization may direct more resources to flower development.