BIODIVERSITY OF MYCORRHIZAL FUNGI IN SA PROGRESS AND CHALLENGES

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1 BIODIVERSITY OF MYCORRHIZAL FUNGI IN SA PROGRESS AND CHALLENGES Prof Joanna Dames Mycorrhizal Research Laboratory Department of Biochemistry and Microbiology Rhodes University

2 What are mycorrhiza? Mutualistic associations between soil fungi and plant roots. Host plant receives mineral nutrients Fungus obtains photosynthetically derived carbon compounds Several types of mycorrhizas Ecto and Endo - mycorrhizas Few plants are non-mycorrhizal

3 Fungal/host associates Ectomycorrhizal Pinus and Eucalyptus plantation Basidiomycota, Ascomycota, Zygomycota Endomycorrizal Ericoid mycorrhizal members of the Ericales (fynbos) Ascomycota, few Basidiomycota Arbusclar mycorrhizal majority of indigenous plants, crops, grasses Glomeromycota Orchid mycorrhizas - mainly Basidiomycota (Nondumiso Khambule Wednesday pm session) Smith and Read 2008 Mycorrhizal Symbiosis; Hawley and Dames 2004 SA J Science

4 Ectomycorrhiza Root tips, variable, age, stage of colonisation and geographic location Morphology Molecular Mantle Fruiting bodies

5 Scleroderma citrinum, 2 different Amanita sp., Thelephora terrestris, Albatrellus sp. tomentelloid, suilloid morphotypes Hawley, Taylor and Dames (2008) SA J Science

6 Challenges Linking above ground fruiting bodies with specific ECM roots difficult Single ECM root tip may be colonised by more than fungus Diversity belowground is greater than aboveground Not all ECM fungi produce mushrooms so not reliable measure of diversity. Not all mushrooms are mycorrhizal Vee Chartier FitzGerald Wednesday pm session

7 Ericoid mycorrhiza Intracellular coiling Morphology Cultural Molecular Dark Septate Endophytes Isolations Jahman Thabede DSE Wednesday pm session

8 Erica - cultural Helotiales dominant in all Erica plants, except E. chamissonis Oidiodendron maius, Meliniomyces sp. from the Rhyzoscyphus erica aggregate identified DSE genera Phialocephala sp.; Cadophora sp., and Lachnum sp. Other Phoma, Cryptosporiopsis, Chaetomium, Acremonium and Epicocum spp. Basidiomycota Mycena sp. Bizabani and Dames 2015 Microbiological Research; Bizabani and Dames - FBIP Small grant

9 Erica 454 pyrosequencing ITS Percentage distribution of the Orders detected from Erica host plants. Nonmetric multidimensional scaling (NMDS) ordination of fungal OTUs composition as detected from six Erica plants at order level. Stress value= 0.08; R2 = 0.80.

10 Erica 454 pyrosequencing ITS Glomerales were identified in E. caffra (0.5%), E. cerinthoides (0.7%) and E. nemorosa (4%). Sebacinales were present in all Erica host plants. OTUs N Closest BLAST match Accession GenBank/UNITE Ecaf Oidiodendron cf. maius KC /SH FU Ecerin Epacris pulchella root associated AY /SH FU fungus EP7 Edem Mycena hudsoniana EU /SH FU Echam Capronia sp. AF /SH FU Enem8 12 Leohumicola verrucosa JN /SH FU Eglum3 45 Meliniomyces bicolor EF /SH FU Bizabani and Dames - FBIP Small grant

11 Bizabani, Fontenla, Dames 2016 Scientia Horticulturae

12 Arbuscular mycorrhiza Extraradical Morphology Molecular Interradical Spore morphology

13 Challenge few characteristics, many species look similar Fungi are unculturable

14 Portulacaria afra - Spekboom ECHO - High Dames & Fulmaka ICOM 2015 HELSPOORT - Medium HOUNSLOW - Weak

15 AM Spekboom 18S NG Sequencing Percentage contribution of Glomeromycotean families in the spekboom plots. Ambisporaceae and Archaeosporaceaea were dominant families in the Echo plot, while members of Claroideoglomeraceae and Geosiphonaceae only occurred in the Helspoort plot, Glomeraceae were dominant in the Hounslow plot.

16 AM - Spekboom Relative abundance (%) of dominant OTUs (contributing > 1%) in the spekboom plots. OTUs 1,2 & 6 representing Paraglomus, 3 & 5 Ambispora, 4 Claroideoglomus and 7 Glomus species. Only OTU 3 & 5 were identified to species level A. leptoticha and A. fennica, respectively.

17 Mycorrhizal benefits Enhanced nutrient uptake and acquisition Promotion of root and plant growth Increased tolerance to stress such as drought, salinity, disease Increased survival Interaction with soil microorganisms Improved soil structure

18 Challenges What is there? Need for baseline data Require more sampling and replication in undisturbed soils/veg Combine traditional with molecular approaches Many soil management practices reduce mycorrhizal populations

19 CONSERVATION OF SOIL BIODIVERISTY BIOLOGICAL CONTROL ENZYMES FOR THE BIOECONOMY PLANTS DON T HAVE ROOTS THEY HAVE MYCORRHIZA PLANT GROWTH PROMOTING RHIZOBACTERIAL INTERACTIONS REHABILATION OF DEGRADED ENVIRONMENTS FUTURE CROPS MYCORRHIZAL RESEARCH LABORATORY