Disease/fungal attacks/treatment of disease

Von Broembsen, S L; Brits, G J.
Phytophthora root rot of commercially cultivated proteas in South Africa.
Plant Disease, v.69, n.3, 1985:211-213
Abstract: Phytophthora cinnamoni was isolated from the roots of 63 spp. of
diseased protease (Proteaceae) in commercial fields in the South Western Cape
Province of South Africa. Disease was often associated with poor soil
drainage. Aboveground symptoms ranged from wilting and rapid death to
chlorosis, decline and eventual death. P. cinnamomi was associated most
frequently with Leucospermum spp. and Leucadendron spp. Pathogenicity of P.
cinnamomi to indigenous proteas in 8 genera (Leucadendron, Leucospermum,
Protea, Aulax, Brabeium, Mimetes, Paranomus, and Serruria) was demonstrated by
artificial inoculation.

Turnbull, L V; Ogle, H J; Stirling, A M; Dart, P J.
Preliminary Investigations Into the Influence of Pseudomonas-Cepacia on Infection and
Survival of Proteas in Phytophthora-Cinnamomi Infected Potting Mix
Scientia Horticulturae (Amsterdam), v.52, n.3, 1992:257-263
Abstract: The potential for biological control by a strain of Pseudomonas
cepacia, selected in vitro for antagonism to the growth of Phytophthora
cinnamomi, was tested for both seedling and cutting propagated proteas. Eight
species of protea were grown from seed in a modified University of California
(UC) potting mix under growth cabinet and glasshouse conditions. In the
absence of Pseudomonas cepacia, root infection was recorded in all species 2
months after pot inoculation with Phytophthora cinnamomi. In five species, 60%
or more plants died during the 150 day trial period. Inoculation with
Pseudomonas cepacia reduced disease incidence with no root infection being
recorded in three species and no deaths in five species. In the remaining
three species, plant mortality was reduced, varying from 20 to 40%. For
cuttings propagated under mist in UC potting mix or wedges of Oasis Grow, the
presence of Pseudomonas cepacia significantly (P < 0.05) reduced root
infection levels in three of the four species tested in both propagation
media. Plant mortality varied from 0 (two species) to 40% during the 60 day
trial period. In the absence of Pseudomonas cepacia, all plants of two species
died with no plant deaths occurring in the remaining two species

Marks, G C; Smith, I W.
Metalaxyl and phosphonate as prophylactic and curative agents against stem infection of Leucadendron caused by Phytophthora cinnamomi.
Australian Journal of Experimental Agriculture, v.32, n.2, 1992:255-259
Abstract: Neither metalaxyl (100 mL of a solution of 2.0 g a.i./L, applied as
a root drench to 10-L pots) nor phosphonate (foliar spray at 1.0 g a.i./L,
applied to runoff) controlled Phytophthora cinnamomi stem infection of
Leucadendron laureolum .times. L. salignum hybrid when applied 10 days after
inoculation. Both fungicides were most effective when applied prior to
inoculation. Neither fungicide was able to kill P. cinnamomi within
established infections. The fungus survived within the vascular tissues of
treated plants. Infection was confined to cortical tissue by wound periderm
when the rate of tissue invasion by P. cinnamomi was slowed by the fungicides.
The results confirm observations made in protea growers' field that with
highly susceptible species, systemic fungicides can have poor curative
properties and should be used as a prophylactic, in conjunction with other
disease control methods.

Serfontein, S; Knox-Davies, P S.
Tip blight of Protea repens.
Phytophylactica, v.22, n.1, 1990:113-116
Abstract: The young growing tips of Protea repens and certain other Protea
spp. in cultivation are commonly blighted. Isolations from blighted tips
yielded a variety of organisms, including Colletotrichum gloeosporioides,
Botrytis cinerea and a Coniothyrium sp., though no pathogen was isolated
consistently. Tunnels caused by insect larvae were also seen. Seedlings
growing in affected and unaffected soils showed differences in the extent of
defoliation. It is postulated that tip blight is caused largely by soil or
climatic stress conditions, and that the pathogens are coincidental or
secondary.

Serfontein, S; Knox-Davies, P S.
Leaf spot of Protea magnifica and copper leaf of Leucospermum cordifolium associated with Coleroa senniana.
Phytophylactica, v.22, n.1, 1990:103-108
Abstract: Coleroa senniana causes leaf specks and yellow to brown discolored
spots on Protea magnifica leaves. Necrotic lesions were recently seen to be
associated with these spots. Isolation and infection studies showed them to be
caused following secondary invasion of the Coleroa lesions by Fusicoccum
aesculi (= Dothiorella aesculi), the anamorph of Botryosphaeria ribis. F.
aesculi appears to gain entry as the pseudothecia burst through the cuticle.
C. senniana was also associated with oily, yellow, confluent spotting
(so-called copper leaf) of Leucospermum cordifolium leaves and shoots, and is
the first record of C. senniana on this host. F. aesculi was less frequently
associated with lesions on L. cordifolium, presumably because the pseudothecia
were widely separated. Light and scanning electron microscopy showed that C.
senniana is largely confined to the cuticle. The systemic fungicides benomyl,
fenarimol, nuarimol, penconazole and triadimefon gave promising control of C.
senniana.

Defrank, J.
The response of nine protea species to spray applications of fluazifop-p.
Tropical Pest Management, v.36, n.2, 1990:145-146
Abstract: The phytotoxicity of two sequential spray applications of the grass
herbicide, fluazifop-p, was determined on nine protea species. Fluazifop-p, at
2.3, 4.5, and 18.0 g a.i./litre, was sprayed onto mature protea plants and a
grassy weed, kikuyu grass (Pennisetum clandestinum Hochst. ex Chiov.), in a
spray-to-drip application. There was no unacceptable crop injury from the 2.3
and 4.5 g a.i./litre spray applications. Unacceptable injury was recorded on
three proteas (Banksia prionotes Lindley., Banksia victoriae Meisn. and
Banksia speciosa R. Br.) with the 18.0 g a.i./litre treatment. Kikuyu grass
was controlled with fluazifop-p at 4.5 and 18.0 g a.i./l.

Hansen, J D; Chan, H T Jr; Hara, A H; Tenbrink, V L.
Phytotoxic reaction of Hawaiian cut flowers and foliage to hydrogen cyanide fumigation.
Hortscience, v.26, n.1, 1991:53-56
Abstract: Phytotoxicity from hydrogen cyanide (HCN) fumigation was measured in
several varieties of Hawaiian cut flowers and foliage (Zingiberaceae,
Heliconia, Orchidaceae, Maranteaceae, Lycopodiaceae, Agavaceae, Proteaceae) as
a potenital disinfestation treatment. Concentrations tested were 2500, 3700,
4600, and 5500 ppm HCN for 30 min. All foliage and most heliconia were
undamaged at fumigation levels of 5500 ppm HCN; most protea and 'Midori'
anthuriums were uninjured at 4600 pm HCN; red and pink ginger were uninjured
at 3700 ppm HCN; and all pincushion protea showed phytotoxicity to HCN. Red
ginger was quickly damaged when exposed to sunlight immediately after
treatment at 2500 ppm HCN. No injury was observed in simulated shipment tests
of red ginger and 'Ozaki' anthuriums fumigated at 2500 ppm HCN. Wet red ginger
flowers longer than 6 cm were damaged at 2500 ppm HCN, whereas shorter flowers
were uninjured. Wet 'Ozaki' anthuriums showed phytotoxicity only at 4600 ppm
HCN. Wet, treated lycopodium and bamboo orchid foliage was not injured. The
number of marketable days and shelf life of the treated plant material were
estimated from the visual ratings.

Hansen, J D; Hara, A H; Tenbrink, A H.
Vapor heat: A potential treatment to disinfest tropical cut flowers and foliage.
Hortscience, v.27, n.2, 1992:139-143
Abstract: Vapor heat treatments to disinfest tropical cut flowers and foliage
were evaluated using a commercial facility. Efficacy was determined for
specific durations against representative Hawaiian quarantine pests on their
plant hosts. Nymphs and adults of aphids, soft and armored scales, mealybugs,
and thrips were killed after 1 hour at 46.6C, and both life stages of aphids
and armored scales along with mealybug nymphs after 2 hours at 45.2C. Injury
to several varieties of Hawaiian floral commodities (Araceae, Musaceae,
Zingiberaceae, Heliconiaceae, Orchidaceae, Marantaceae, Lycopodiaceae,
Agavaceae, Proteaceae) during these treatments was determined. Large
heliconias, most red ginger, bird-of-paradise flowers and leaves, and most
foliage were not damaged; anthuriums, pincushion protea, and orchid flowers
and foliage were very sensitive to vapor heat. Treatment modification was
needed to reduce plant injury to these commodities without losing efficacy.
The number of shelf-life days of the treated plant material was estimated from
the visual ratings.

Defrank, J; Easton-Smith, V A.
Evaluation of pre-emergence herbicides on four proteaceous species.
Tropical Agriculture, v.67, n.4, 1990:360-362
Abstract: Sequential applications of three pre-emergence herbicides were made
to four species of newly planted proteas. Herbicides were applied at
three-month intervals over a two-year period. Protea trunk diameter growth in
response to herbicide treatments and two types of synthetic mulch were
recorded after a one-year establishment period. Protea neriifolia R. Br.
growth was significantly reduced by oryzalin at 6.7 kg a.i. ha-1. Banksia
menziesii R. Br. growth was reduced in untreated plots where weeds were
removed by hoeing: growth of all other proteas was improved with weed removal.
Growth of all other Protea species was unaffected by herbicide applications.
Synthetic mulches of woven black polypropylene and a polyester spunbound
fabric did not adversely affect protea growth. However, the polyester mulch
collected soil, providing a surface for weed-seed germination and growth
through the fabric. All herbicides tested provided adequate weed control, but
oryzalin provided only marginal control of a leguminous weed, Medicago
truncatula Gaertn.

Benic, L M; Knox-Davies, P S.
Anthracnose of Protea compacta, caused by Colletotrichum gloeosporioides.
Phytophylactica, v.15, n.3,:109-120
Abstract: C. gloeosporioides was regularly isolated from stem lesions of a
dieback disease of P. compacta. It was frequently accompanied by a
Botryosphaeria. Both fungi were inoculated into stems of mature P. compacta
plants. Only C. gloeosporioides caused typical dieback symptoms, but lesions
were more extensive when both fungi were present. Both fungi were isolated
from seed receptacles and seed, but only C. gloeosporioides was recovered from
damped-off and blighted seedlings in the glasshouse. Seedlings inoculated with
C. gloeosporioides developed typical damping-off and blight. A warm
(30.degree. C) thiram soak and thiram dusting applied to seed after 30 min hot
water (50.degree. C) treatment gave good control of seedling diseases. Seed
treatment also enhanced seed germination. Captab was phytotoxic to developing
seedlings.

Smith, W A; Engelbrecht, M C; Knox-Davies, P S.
Studies on Batcheloromyces leaf spot of Protea cynaroides.
Phytophylactica, v.15, n.3,:125-132
Abstract: Observations were made of symptom development by Batcheloromyces
proteae on different P. cynaroides variants with different degrees of
susceptibility. A [scanning electron microscope] SEM study confirmed details
of the superficial growth and sporulation of the fungus on its host. B.
proteae grew extremely slowly on potato-dextrose agar. Its optimum growth
temperature was 22.degree. C.

Crous, Pedro W.; Palm, Mary E..
Systematics of selected foliicolous fungi associated with leaf spots of Proteaceae. Mycological Research, v.103, n.10, Oct., 1999.:1299-1304.
Abstract: The present study treats several fungi associated with leaf spots of
Proteaceae from Africa, Australia and India. Leptosphaeria leucadendri
(anamorph: Sclerostagonospora leucadendri) is described from Leucadendron
leaves from Australia, while three previously described African taxa from
Protea leaves are transferred to Phaeophleospora as P. abyssinicae, P.
congestum and P. protearum. Trimmatostroma protearum and a Phyllosticta sp.
are described from Protea leaves collected in South Africa and Australia,
respectively. Cercospora agharkarii, which occurs on Grevillea, is redisposed
to Pseudocercospora, while a new genus Pseudohendersonia, is proposed for P.
proteae occurring on Protea leaves in South Africa.

Swart, L.; Denman, S.; Lamprecht, S. C.; Crous, P. W..
Fusarium wilt: A new disease of cultivated Protea in Southern Africa.
Australasian Plant Pathology, v.28, n.2, 1999.:156-161.
Abstract: A newly recorded disease of cultivated Protea, Fusarium wilt, is
described and shown to be caused by Fusarium oxysporum. The disease occurs on
mature plants (2-year-old) of P. aristata X repens cv. Venus, P. compacta X
susannae cv. Pink Ice, P. cynaroides, P. eximia X susannae cv. Cardinal, P.
eximia X susannae cv. Sylvia, P. magnifica X susannae cv. Susara and P. repens
cv. Sneyd in the summer rainfall areas of the North-Western province of South
Africa and in Zimbabwe. Disease symptoms first become visible as necrotic
leaves. Subsequently, a dark lesion develops from the roots along the stem,
usually visible only on one side of the stem. Occasionally the lesion develops
in the upper part of the stem. The vascular tissue is discoloured leading to
branch die-back and plant death. F. oxysporum was readily isolated from the
roots, crown and vascular tissues of infected plants. Koch's postulates were
proved on six Protea cultivars. Disease symptoms similar tothose observed in
the field developed 6 weeks after inoculation on all cultivars. The fungus was
re-isolated from the roots, crown and vascular tissues of inoculated plants.
This is the first record of Fusarium wilt on Protea plants.

Swart, L.; Taylor, J. E.; Crous, P. W.; Percival, K..
Pestalotiopsis leaf spot disease of Proteaceae in Zimbabwe.
South African Journal of Botany, v.65, n.3, June, 1999.:239-242.
Abstract: A species of Pestalotiopsis Steyaert was consistently isolated from
necrotic leaf spots on Leucospermum R. Br. and Protea L. species in Zimbabwe.
Inoculation studies were conducted to prove pathogenicity and it was confirmed
that the Pestalotiopsis sp. was the causal agent of the disease. A description
of this fungus is given and it is compared to other Pestalotiopsis spp.
recorded from Proteaceae.

Denman, Sandra; Crous, Pedro W.; Wingfield, Michael J..
A taxonomic reassessment of Phyllachora proteae, a leaf pathogen of Proteaceae.
Mycologia, v.91, n.3, May-June, 1999.:510-516.
Abstract: Phyllachora proteae is a well known leaf pathogen of Protea spp. In
the present study this fungus was recollected from several genera and species
of Proteaceae in the Western Cape province of South Africa, and its taxonomy
was reassessed. Single ascospore cultures produced a Fusicoccum anamorph in
culture, described here as F. proteae. A microconidial synanamorph with
narrowly ellipsoidal, brown, thick-walled conidia was commonly associated with
F. proteae in culture. Based on its bitunicate asci, as well as pseudothecial
and ascospore morphology, a new combination for P. proteae is proposed in
Botryosphaeria, as B. proteae.

Viljoen, C. D.; Wingfield, B. D.; Wingfield, M. J..
Relatedness of Custingophora olivaceae to Gondwanamyces spp. from Protea spp.
Mycological Research, v.103, n.4, April, 1999.:497-500.
Abstract: Species of Gondwanamyces are unusual amongst the ophiostomatoid
fungi in that they are associated with the infructescences of Protea in South
Africa. These fungi are distinguished from other ophiostomatoid genera by
their Knoxdavesia anamorphs. Knoxdavesia spp. are peripherally similar, but
distinct from Stachybotrys and Phialocephala. They are, however,
morphologically identical to Custingophora. Custingophora olivaceae, was
isolated from compost in Germany, a niche very different from that associated
with fungi from Protea spp. The similarity of Custingophora and Knoxdavesia is
such that they cannot be distinguished morphologically. The notion that
Gondwanamyces might represent a teleomorph for Custingophora is intriguing. To
determine whether an anamorph-teleomorph connection exists between Knoxdavesia
and Custingophora, we determined the sequence of approximately 1100
nucleotides from the large subunit (LSU) ribosomal RNA gene. Results suggest
that species of Gondwanamyces and C. olivaceae are phylogenetically related.
This, as well as their morphological similarity suggests that Gondwanamyces
and C. olivaceae have a shared ancestry. They are, however, sufficiently
different that Gondwanamyces is probably not a teleomorph for Custingophora
olivaceae.

Spaaij, F.; Weber, G.; Smith, M. T..
Myxozyma vanderwaltii, new species (Candidaceae), a new yeast species isolated from a flower of Protea repens
(L.) L. Antonie van Leeuwenhoek, v.63, n.1, 1993.:17-21.
Abstract: Three strains of an undescribed species of the genus Myxozyma were
recovered. The new species differs from other accepted species of the genus in
its assimilation pattern of carbon sources, mol% G + C and low DNA-DNA
homolgy. A description of the new species, Myxozyma vanderwaltii, and a key to
the species accepted in the genus are given.

Mouton, Marnel; Wingfield, Michael J.; Schalk Van Wyk, P..
Conidium development in the Knoxdaviesia anamorph of Ceratocystioposis proteae.
Mycotaxon, v.46, n.0, 1993.:363-370.
Abstract: Ceratocystiopsis proteae and its anamorph, Knoxdaviesia proteae,
occur commonly in the infructescences of Protea repens. Conidia of K. proteae
are produced in a gloeoid mass at the apices of phialidic conidiogenous cells.
It would thus be expected that the conidia should be produced by apical wall
building with enteroblastic proliferation and holoblastic ontogeny. TEM
examination of conidium development in K. proteae, however, revealed the
presence of a delimitation wall layer continuous with the new conidium inner
wall. This might indicate some relationship with the ring wall building
process. It is our opinion that the wall orientation in this case represents a
hitherto unrecognized variation in phialidic conidial development.

Swart, L.; Crous, P. W.; Denman, S.; Palm, M. E.. Fungi occurring
on Proteaceae.
I. South African Journal of Botany, v.64, n.2, April, 1998.:137-145.
Language: English; Pub type: JOURNAL ARTICLE
Abstract: The present study has led to the description of several new fungi
occurring on leaves of Protea L., Leucospermum R.Br., Telopea R.Br. and
Brabejum L. collected from South Africa, Australia or New Zealand.
Cladophialophora proteae L. Viljoen & Crous, Coniothyrium nitidae Crous & S.
Denman, Coniothyrium proteae Crous & S. Denman, Coniothyrium leucospermi Crous
& S. Denman, Harknessia leucospermi Crous & L. Vilioen, and Septoria protearum
L. Viljoen & Crous spp. nov. are described from Protea and Leucospermum in
South Africa, while Phyllosticta owaniana G. Winter is redescribed from leaves
of Brabejum stellatifolium L. Furthermore, Mycosphaerella telopeae M. Palm &
Crous sp. nov. is described from leaves of Telopea collected in New Zealand,
while Phyllosticta telopeae H.Y. Yip, which also occurs on this host, is
described in culture from Australian material.

 

Marais, Gert J.; Wingfield, Michael J.; Viljoen, Christopher D.;
Wingfield, Brenda D.. A new ophiostomatoid genus from Protea infructescences.
Mycologia, v.90, n.1, Jan.-Feb., 1998.:136-141.
Language: English; Pub type: JOURNAL ARTICLE
Abstract: In recent years, two unusual ophiostomatoid fungi, Ceratocystiopsis
proteae and Ophiostoma capense, have been described from infructescences of
Protea spp. They are unique in having Knoxdaviesia anamorphs and differ from
each other in ascospore morphology. Both species are sensitive to
cycloheximide, typical of Ceratocystis s. s. In this study, RFLP analyses were
done on the rRNA operon regions of the type species of Ceratocystis,
Ophiostoma and Ceratocystiopsis as well as C. proteae and O. capense using the
restriction enzymes Eco RI, Hae II, Pst 1, Sal 1, Sma I and Xba I. By
constructing restriction maps, phylogenetic relationships between these
species were determined. From the data, it was evident that C. proteae and O.
capense are phylogenetically unrelated to both Geratocystis and Ophiostoma,
but showed a closer affinity to Ceratocystis than to Ophiostoma. Based on the
RFLP analyses, cycloheximide sensitivity, cell saccharides, and anamorph
morphology, a new genus, Gondwanamyces, is established to accommodate these
two unusual fungi.