Vineyard management systems influence arbuscular mycorrhizal fungi recruitment by grapevine rootstocks in New Zealand.

Arbuscular mycorrhizal fungi (AMF) can perform significant functions within sustainable agricultural ecosystems, including vineyards. Increased AMF diversity can be beneficial in promoting plant growth and increasing resilience to environmental changes. To effectively utilize AMF communities and their benefits in vineyard ecosystems, a better understanding of how management systems influence AMF community composition is needed. Moreover, it is unknown whether AMF communities in organically managed vineyards are distinct from those in conventionally managed vineyards. In this study, vineyards were surveyed across the Marlborough region, New Zealand to identify the AMF communities colonizing the roots of different rootstocks grafted with Sauvignon Blanc and Pinot Noir in both conventional and organic systems. The AMF communities were identified based on spores isolated from trap cultures established with the collected grapevine roots, and by next-generation sequencing technologies (Illumina MiSeq). The identified AMF species/genera belonged to Glomeraceae, Entrophosporaceae, and Diversisporaceae. The results revealed a significant difference in AMF community composition between rootstocks and in their interaction with management systems. These outcomes indicated that vineyard management systems influence AMF recruitment by rootstocks and some rootstocks may therefore be more suited to organic systems due to the AMF communities they support. This could provide an increased benefit to organic systems by supporting higher biodiversity.

Moukarzel R ，Jones EE ，Panda P ，Larrouy J ，Ramana JV ，Guerin-Laguette A ，Ridgway HJ ... -  《-》

Grapevine rootstocks drive the community structure of arbuscular mycorrhizal fungi in New Zealand vineyards.

Arbuscular mycorrhizal fungi (AMF) are often regarded as non-specific symbionts, but some AMF communities show host preference in various ecosystems including vineyards. Grapevine plants are very responsive to AMF colonization. Although these fungi have potentially significant applications for sustainable agricultural ecosystems, there is a gap in knowledge regarding AMF-grapevine interactions worldwide and especially in New Zealand. This study focused on identifying AMF taxa colonizing grapevines in New Zealand vineyards and investigated the effect of grapevine rootstocks on AMF community diversity and composition. Denaturing gradient gel electrophoresis (DGGE) and trap cultures were used to characterize the AMF communities. Grapevine roots from three vineyards and nine rootstocks were analysed by DGGE and used in trap cultures for AMF recovery. Trap cultures allowed the recovery of six AMF spore morphotypes that belonged to Ambispora sp., Claroideoglomus sp., Funneliformis sp. and Glomus sp. Bands excised, reamplified and sequenced from the DGGE were assigned to Glomus sp., Rhizophagus sp. and Claroideoglomus sp. The AMF community analyses demonstrated that rootstock significantly (P < 0·05) influenced the AMF community composition in all sites. The study showed that for a comprehensive identification of AMF, both results from trap culture and molecular work were needed and that the rootstock cultivar was the main driver of the arbuscular mycorrhizal community colonizing the roots. This study provides a firm foundation for future research exploring the beneficial use of AMF in enhancing grapevine production and sustainability.

Moukarzel R ，Ridgway HJ ，Guerin-Laguette A ，Jones EE ... -  《-》

Soil Arbuscular Mycorrhizal Fungal Communities Differentially Affect Growth and Nutrient Uptake by Grapevine Rootstocks.

Arbuscular mycorrhizal fungi (AMF) deliver potentially significant services in sustainable agricultural ecosystems, yet we still lack evidence showing how AMF abundance and/or community composition can benefit crops. In this study, we manipulated AMF communities in grapevine rootstock and measured plant growth and physiological responses. Glasshouse experiments were set up to determine the interaction between rootstock variety and different AMF communities, using AMF communities originating under their own (i.e., "home") soil and other rootstocks' (i.e., "away") soil. The results revealed that specific AMF communities had differential effects on grapevine rootstock growth and nutrient uptake. It was demonstrated that a rootstock generally performed better in the presence of its own AMF community. This study also showed that AMF spore diversity and the relative abundance of certain species is an important factor as, when present in equal abundance, competition between species was indicated to occur, resulting in a reduction in the positive growth outcomes. Moreover, there was a significant difference between the communities with some AMF communities increasing plant growth and nutrient uptake compared with others. The outcomes also demonstrated that some AMF communities indirectly influenced the chlorophyll content in grapevine leaves through the increase of specific nutrients such as K, Mn, and Zn. The findings also indicated that some AMF species may deliver particular benefits to grapevine plants. This work has provided an improved understanding of community level AMF-grapevine interaction and delivered an increased knowledge of the ecosystem services they provide which will benefit the wine growers and the viticulture industry.

Moukarzel R ，Ridgway HJ ，Waller L ，Guerin-Laguette A ，Cripps-Guazzone N ，Jones EE ... -  《-》

Decrease in diversity and changes in community composition of arbuscular mycorrhizal fungi in roots of apple trees with increasing orchard management intensity across a regional scale.

Understanding which factors drive the diversity and community composition of arbuscular mycorrhizal fungi (AMF) is important due to the role of these soil micro-organisms in ecosystem functioning and current environmental threats to AMF biodiversity. Additionally, in agro-ecosystems, this knowledge may help to evaluate their use in making agriculture more sustainable. Here, we used 454-pyrosequencing of small subunit rRNA gene amplicons to quantify AMF diversity and community composition in the roots of cultivated apple trees across 24 orchards in central Belgium. We aimed at identifying the factors (soil chemical variables, organic vs. conventional farming, and geographical location) that affect AMF diversity and community composition. In total, 110 AMF OTUs were detected, of which the majority belonged to the Glomeraceae (73%) and the Claroideoglomeraceae (19%). We show that soil characteristics and farming system, rather than the geographical location of the orchards, shape AMF communities on apple trees. Particularly, plant-available P content of the soil was associated with lower AMF diversity. In orchards with a lower plant-available P content of the soil (P < 100 mg/kg soil), we also found a significantly higher AMF diversity in organically managed orchards as compared to conventionally managed orchards. Finally, the degree of nestedness of the AMF communities was related to plant-available P and N content of the soil, pointing at a progressive loss of AMF taxa with increasing fertilization. Overall, we conclude that a combination of organic orchard management and moderate fertilization may preserve diverse AMF communities on apple trees and that AMF in the roots of apple trees appear not to be dispersal limited at the scale of central Belgium.

van Geel M ，Ceustermans A ，van Hemelrijck W ，Lievens B ，Honnay O ... -  《-》

The diversity of arbuscular mycorrhizal fungi amplified from grapevine roots (Vitis vinifera L.) in Oregon vineyards is seasonally stable and influenced by soil and vine age.

Schreiner RP ，Mihara KL 《MYCOLOGIA》