Truffles and mushrooms (Consulting) Limited

© Truffles and Mushrooms (Consulting) Ltd                     

Commercial inoculation of Pseudotsuga  (Douglas fir) with an ectomycorrhizal fungus and its consequences.  
Hall, I.R.; De La Mare, P.; Bosselmann, G.; Perley, C.; Wang, Y.  2019.  In: Kandikere R. Sridhar & Sunil K. Deshmukh (Eds.), Advances in macrofungi: diversity, ecology and biotechnology.  Boca Raton, CRC Press.   

Deforestation in New Zealand was recognised as undesirable as early as the mid-1800s but it was not until the 1920s and 1930s that government took a strong hand in the management of forests. In 1960 the government proposed to double exotic forests to 800,000 hectares by 2000 and plant a further 400,000 hectares by 2025 with the aim of increasing income from exotic forests to 25% of export earnings by 2000. By 1993 there were 1.34 million hectares of exotic forest in New Zealand. Radiata pine (Pinus radiata) made up 90% of these forests and Douglas-fir (Pseudotsuga menziesii) 5% although in Otago and Southland Douglas-fir accounted for 10% of the total 137,000 hectares. The rotation time for Douglas fir is longer than radiata pine but it produces higher quality timber that does not need to be chemically treated to ensure durability and protection against wood borer. So in the 1990s plans were made by Ernslaw One Ltd, a New Zealand Forest production company, to extend Douglas fir plantings on poor quality upland pastures in Otago and Southland. It was also planted on similar land in Canterbury.

When large numbers of containerised Douglas fir destined for runout pastures became chlorotic in a large purpose-built greenhouse near Oamaru, a research programme was instigated to define the problem and then rectify it. Previous work had shown that possible reasons for the chlorosis were nutritional issues, lime-induced chlorosis linked to iron and magnesium deficiency, manganese induced iron deficiency, herbicide damage, or a lack of effective ectomycorrhizal fungi.

A large survey of green and chlorotic Douglas firs in New Zealand and in nurseries found that a lack of mycorrhizas on chlorotic trees whereas green healthy trees in the field were consistently mycorrhizal. Experiments determined that suspensions of Rhizopogon parksii spores could be used to establish mycorrhizas on Douglas fir providing the normal rate of nutrients applied in a greenhouse was reduced. Subsequently a commercial method was devised for producing tens of millions of containerised Douglas fir mycorrhized with R. parksii. These trees are now 25 years old, are growing well and there is no sign of chlorosis

Truffles and Morels: Two Different Evolutionary Strategies of Fungal-Plant Interactions in the Pezizales.  
Ori, F.; Hall, I.R.; Gianchino, C.; Iotti, M.; Zambonelli, A.  2019.   In, Ajit Varma, Swati Tripathi and Ram Prasad (Eds.),
Plant Microbe Interface, Springer.  https://link.springer.com/chapter/10.1007/978-3-030-19831-2_3

Pezizales are a widespread group of fungi, basal to the other filamentous ascomycetes. Most species live in soil as saprobes, in a mycorrhizal relationship with a wide range of plants, or as plant parasites. The lineage Morchellaceae–Discinaceae–Helvellaceae–Tuberaceae includes most of the commercially valuable species in the order. The truffles in the genus Tuber and morels in the genus Morchella arguably command more interest in culinary circles than any other groups of mushrooms. In recent years, the interactions of these fungi with plants have been thoroughly researched although many aspects still need to be clarified. In this chapter, we describe and compare these two groups of mushrooms and take a look at the evidence as to whether there are real trophic differences from those traditionally held and if things are not quite as simple as our forebears would have had us believe. We explore the range of host plants involved in the interactions, the morpho-anatomy of symbiotic structures, the molecular mechanisms of symbiosis, and the influence of other microbial species.

Treasures of the forest floor – an under-researched and underfunded bounty
Halll, I.R.; Xiong, W.P.; Zhang, J.L.; Wang, D.  2018.  
An expansion of an oral paper presented at the 9th International Conference on Mushroom Biology and Mushroom Products, 12-19 November 2018, Shanghai and Zhengzhou, China.  https://www.researchgate.net/publication/332538979

About half of the world’s favourite wild edible mushrooms form intimate mycorrhizal associations with the roots of suitable host plants. The first of these to be cultivated were the truffles about 220 years ago. The method is usually attributed to Joseph Talon (Hall et al. 2007) from Saint Saturnin-lès-Apt, France. The story goes that it was Talon who discovered that if self-sown seedlings found under truffle trees were transplanted into a new area eventually they too would produce truffles. However, Pierre Mauléon (1744-1831), a miller in the small village of Beuxes near Loudun, in the Poitou-Charentes region of France, is credited with the same discovery in 1790 – twenty years before Talon (Hall & Zambonelli 2012). Another method was described in 1807 in a report by Giovio to Canonico Giacomo Sacchetti, the secretary of the Siena Academy, in which seedlings were inoculated with pieces of truffle (Hall & Zambonelli 2012). These methods were a great success and truffières (truffle plantations) became widely established in France and Italy (Hall et al. 2008; Hall & Zambonelli 2012).

Recent papers of interest