Meetings & Field Trips

Evening Meeting:  Wednesday 6th May

7:30pm Unitec

Two Talks:

Ellie Fajer: 'Investigating the Potential of

Fungal Endophytes to Combat Kauri

Dieback'

For my master’s thesis at the University of

Auckland, I investigated how phosphite

treatments to Phytophthora agathidicida-

symptomatic and asymptomatic kauri (Agathis

australis) may affect their root and soil fungal

communities. Thanks to funding from the

Auckland Botanical Society through the Lucy

Cranwell Grant, I conducted fieldwork across

kauri forests in the Auckland region. I utilized

molecular meta-barcoding to profile the soil and

root-inhabiting fungal communities of kauri

trees, some affected by P. agathidicida and/or

treated with phosphite injections. I developed

models predicting which environmental and

management factors impact fungal community

composition, finding that phosphite treatments for

kauri are a significant predictor of their root and soil

fungal communities. For symptomatic kauri treated

with phosphite, I found that their root fungal

communities showed significant signs of recovery three

years following phosphite treatments. Finally, I found

that while phosphite applications to symptomatic trees

improved rates of fungal root colonization, phosphite

applications to asymptomatic trees were linked to

significantly lower root fungal abundance. Ultimately,

while phosphite treatments can be effective in slowing

the progression of kauri dieback and other

Phytophthora-driven plant diseases, my research

demonstrates that such treatments may have broader

impacts on plant-associated microbial community

structure and functioning, especially when applied

preventatively to asymptomatic trees.

Abdulwakeel Ajao - Towards a new

classification of Rhynchosia (Leguminosae,

Phaseoleae) and related genera: A

comprehensive phylogeny of Cajaninae

Rhynchosia is the largest genus in the subtribe

Cajaninae of the tribe Phaseoleae in the family

Fabaceae. In southern Africa, the genus has not

been revised in more than 100 years and was

therefore classified by the South African

National Biodiversity Institute as a priority genus

in need of taxonomic revision. Consequently,

many species are poorly known and thus difficult

to identify, while their distribution ranges and

correct typification have not been properly

established. Furthermore, there is a dearth of

information on the phylogenetic relationships of

the genus and its allied genera within the subtribe

Cajaninae. In this talk, I will present advances in

taxonomic studies of the genus Rhynchosia in

southern Africa and in phylogenetic analyses of

the genus and related genera in the subtribe

Cajaninae. Morphological studies revealed a

number of characters that can be used to

distinguish closely related species within the

genus Rhynchosia. These include growth habit,

stipule type, leaf indumentum, inflorescence type

and length, calyx and standard petals

indumentum. The phylogenetic results suggest

that a new classification is needed to

circumscribe a monophyletic Rhynchosia and

recircumscribe other genera in the subtribe

Cajaninae.

Field trip: Auckland Botanic Gardens and

Puhinui Forest, Saturday 16th May

Leader: Ella Rawcliffe

Meeting time: 10 am

Meeting place: Northern entrance to the

Auckland Botanic Gardens at 177 Everglade

Drive, Totara Heights. Street parking available

on Everglade Drive and surrounding streets.

We will view the biosecurity

enclosures in the interests of becoming familiar

with the Low Incidence Pest Plants, which

Auckland Council is aiming to eradicate from the

region:

www.aucklandcouncil.govt.nz/en/environment/what-we-do-to-help-environment/our-biodiversity-%20projects/eradicating-low-incidence-pest-plants.html 

After this, we will head through the Gondwana

Arboretum where I will leave you for self-directed

exploration in the Puhinui Forest, armed with a species

list compiled by Mike Wilcox (below) from previous

ABS visits, independent visits, BioBlitz, and herbarium

records.

Health and Safety: Please note this area of the Botanic

Gardens also includes an off-leash dog park. While I

don’t anticipate a problem, in the interest of being

prepared you may want to save the number of Animal

Management: 0800 462 685.