Mycorrhizal syntheses betweenLactariusspp. sectionDeliciosiandPinusspp. and the effects of grazing insects in Yunnan, China

Abstract

Ectomycorrhizal fungi (EMF) in Lactarius sect. Deliciosi produce valuable edible mushrooms. Market supplies are harvested from natural populations. Sustainable cultivation could increase commercial crop production. The first step in EMF cultivation is the production of host seedlings well-colonised by the target species. The aim of this study was to compare the efficiency of vegetative versus spore inoculum for controlled mycorrhizal synthesis between Lactarius and Pinus species native to China. Inoculated seedlings were incubated in a glasshouse for up to 14 months. Mycorrhizae were synthesised, using vegetative inoculum, for 13 distinct combinations of five Pinus and four Lactarius species, 12 of these unprecedented. Spore inoculation was not successful. The successful mycorrhization presented here provides a foundation for establishing mushroom orchards, with L. deliciosus x P. yunnanensis or P. radiata, L. hatsudake x P. yunnanensis or P. tabuliformis, and L. vividus x P. massoniana or P. radiata appearing promising symbionts for cultivation. From 5 months following inoculation, mycorrhizal seedlings underwent extensive insect grazing. Adult forms of Bradysia impatiens were the most frequent insects caught on sticky traps, while their larvae were observed foraging through roots. The control of insects in the nursery will be critical to large-scale production of mycorrhizal seedlings.

Transcriptome Profiling Reveals Differential Gene Expression of Secreted Proteases and Highly Specific Gene Repertoires Involved in Lactarius–Pinus Symbioses

“…To find out the compatible host species for each Lactarius , an assay involving five pine species ( P. massoniana , P. sylvestris , P. taeda , P. tabuliformis , and P. yunnanensis ) was performed mainly using an in vitro “pouch” coculture system modified from Guerin-Laguette et al(2000 ; Supplementary Figure 1 ). The combinations involving P. tabuliformis and P. yunnanensis were assayed with a traditional pot system described in Wang et al (2019) , since aseptic seedlings could not be produced. Pine seeds were sterilized with 10% H 2 O 2 solution and germinated on 1% agar plate at 25°C, 14/10 h (day/night).…”

“…Fast-growing mycelia was prepared 2 weeks before coculture by sub-culturing mycelial agar plugs (ca. 0.5 cm × 0.5 cm) on fresh 1 /2 MMN + 1 /2 PDA medium (Wang et al, 2019), covered with a cellophane membrane.…”

Edible mycorrhizal fungi of the world: What is their role in forest sustainability, food security, biocultural conservation and climate change?

“…Conservation of this precious biocultural resource remains a vital and urgent issue. Great efforts were encouraged to use EMF in a sustainable way in order to promote rural development (Brown et al., 2018; Geng et al., 2009; Wang, Guerin‐Laguette, Butler et al., 2019; Wang, Guerin‐Laguette, Huang et al, 2019), including (a) improvement of public awareness for environmental protection and sustainable development, (b) development of EMF cultivation to improve quality and supply and reduce harvest pressure, and (c) promotion of mycotourism and development of mushroom gastronomy in rural agro‐ and slow‐food tourism (Liu et al., 2018). However, the most important action has been the forest ownership reformation which occurred in 2008, giving farmers the right to manage forest products including wild mushrooms.…”

“…2009; Huang et al., 2020; Wan et al. 2016; Wang, Guerin‐Laguette, Butler et al., 2019; Wang, Guerin‐Laguette, Huang, 2019; Wang et al, 2020).…”

Successes and challenges in the sustainable cultivation of edible mycorrhizal fungi – furthering the dream

“…Deliciosi (Fr.:Fr.) Redeuilh, Verbeken & Walleyn (Wang et al, 2019b), and Rhizopogon roseolus (Corda) Th. Fr.…”