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Anthostomella on pine needles in Scotland
[ 28 3 ] Trans. Br. mycol. Soc. 70 (2) 283-315 (1978).
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NOTES AND BRIEF ARTICLES ANTHOSTOMELLA ON PINE NEEDLES IN SCOTLAND SHEILA M. FRANCIS
Commonwealth Mycological Institute, Kew
Four species of Anthostomella Sacco have been recorded on Pinus in Europe (Francis, 1975). These fungi are rarely collected and few exsiccati have been found in herbaria. Only one of the Pinus species, A. formosa Kirschst., has been recorded for this country and it was known only from a culture sent to this Institute in 1971 by Dr C. S. Millar of Aberdeen University. He had isolated the fungus from first-year needles, green and apparently healthy, of Corsican pine (Pinus nigra var. maritima (Aiton) Melville) from Culbin Forest, Moray, Scotland. At the Aberdeen foray in September 1975 I collected a quantity of fallen needles of Corsican pine from the litter beneath the trees from which the isolations had been made. Prolonged searching of many hundreds of needles eventually produced six which yielded between them about twenty perithecia of A. formosa. This very low proportion of perithecia present in the litter continued in later collections sent to me from Culbin and agrees with the experience of Dr Millar and his colleagues. In 1975 Dr Millar showed me some needles of Pinus sylvestris from the island of Rhum in the Inner Hebrides with perithecia of an Anthostomella sp., identified as such by Dr S. C. Gregory of the Forestry Commission, Roslin, Midlothian. This proved to be A. pedemontana Ferr. & Sacc., known previously only from northern Italy and West Pakistan. I was able to visit Rhum and the neighbouring island of Canna in August 1976 and collected fallen needles of both Corsican and Scots pine. These yielded, in later examination, abundant material of the four European species of Anthostomella and, in addition from Canna, a species that closely resembled A. sabinianae S. Francis, a taxon described on needles of the Digger pine, Pinus sabiniana, from California (Francis, 1975), i.e. all the species ever recorded on Pinus. Descriptions of these fungi have already been given (Francis, 1975). Only the more important details are included in Table 1, and the spores are illustrated in Fig. 1. The collections of A. formosa and A. pedemontana agreed closely with the type material; those of A. conorum and A. sabinianae differed slightly. The type material of A. conorum was collected on cone scales of Scots pine and the
three other collections at Herb. K and IMI that I have seen were also on cone scales. A clypeus was present in these examples. No clypeus was seen in sections of needles of the Rhum material. A similar difference existed between the type material of A. sabinianae from California and the Canna collection. In the Californian specimens, on needles of Digger pine, there was a conspicuous circular clypeus which is absent in the Canna material on Corsican pine. There appear to be no obvious anatomical features in the pine needles to account for this difference. It should be noted that it is unusual for the species on pine needles to have a clypeus and the type material of A. sabinianae is the only collection I have seen with a clypeus. If this difference is maintained in subsequent collections I think the taxa should be separated at least at varietal level but I do not wish to do so on one collection. I hope to get further material from the Small Isles and west coast of Scotland and would be most grateful for the loan or gift of any other collections. It is obvious that the damp, relatively mild climate of Rhum and Canna is more favourable to the growth of these fungi than the much dryer and colder weather conditions prevailing at Culbin on the east coast. What is surprising is to find this range of species present especially on two islands where there are few mature trees, all of which have been planted this century. Dennis (1964) in his study of 'The Fungi of the Isle of Rhum' first made this general point stating that 'The usual mycorrhizal fungi, parasites and saprophytes have accompanied or followed their hosts in these isolated tree plantings ... to a remarkable degree.' On Rhum the mature trees cluster round Kinloch Castle at the head of Loch Scresort and also form a thin line along the south shore of the loch. My collections on Rhum were made from litter beneath Corsican pine immediately behind the jetty (site LS); from Scots pine in the Deer reserve to the west of the Castle (DR); and a to-year-old stand of Scots pine 3 miles west of the Castle in the Kilmory plots (KP). On Canna the oldest trees are a stand of Corsican pine on Compass Hill planted 70 years ago. The four trees of Scots pine which are adjacent to the Corsican pine are 5-7
Notes and brief articles
c
R
A
[)
20//111
Fig. 1. Ascospores of (A) Anthostomella conorum (IMI 208976e), (B) A. formosa (IMI 197142), (C) A. pedemontana (IMI 214112), (D) A. sabinianae (IMI 208976d).
Table
1.
Diagnostic characters of Anthostomella species found on Pinus Ascospores ~--------"----~-------,
Germ
Asci (pm) A. conorum (Fckl) Sacc.*
96-140 x 10-13
Size (pm) 13-17 x 7-9
Cell no. 1
slit (pm) = length
of spore A.formosa Kirschst, A. pedemontana Ferr. & Sacc.* A. sabinianae S. Francis*
120-135 x 8 110-113 X 9-12 111-133 X 8-10
13'5-15"5 x 6-7 13-16 x 6-7 14-15 x 6-7
2 1 2
7- 1 0 6 = length of spore
Sheath
+ + + +
* Denotes a new record for Britain.
years old and came originally from Rhum. The distribution of species of Anthostomella as shown by these collections is given in Table 2. I visited Rhum and Canna again in 1977 and made further collections. The results from Rhum were similar to those reported for 1976. Fallen cones of Pinus nigra were examined for A. conorum without success although the fungus was present on fallen needles at this site. A sample of cones and needles collected in June by Dr David Minter gave the same result. Trans. Br. mycol. Soc. 70 (2) (1978).
Collections at Canna were made at the edge of the Corsican pine wood on Compass Hill (1976 collections came from the centre of the wood). The fallen needles again yielded A. sabinianae without a clypeus but in addition, on this occasion, specimens of the fungus were found with a distinct, well-defined dypeus which appeared exactly similar to the Californian material. The most obvious difference between the two sites is that the edge of the wood is warm and sunny while the centre is nearly devoid of sun and appreciably
Printed in Great Britain
Notes and briefarticles Table
2.
Location of Anthostomella spp. on Rhum and Canna
A. conorum
Ai formosa
A. pedemontana
A. sabinianae
Rhum P. syluestris
+
Site DR Site KP
+
P. nigra
Site LS
+
+
+
+
Canna P. syluestris
P. nigra
cooler even when visited on an exceedingly hot day in the summer of 1976. It is a pleasure to acknowledge the help I have had from Dr Colin Millar. I thank the Nature Conservancy for allowing me to collect on Rhum and the Chief Warden, Peter Corkhill, for his assistance; Dr and Mrs J. Lome Campbell for permission to land and collect on Canna and for their kind hospitality to my husband and me. The loan of a microscope from the Scientific Investiga-
+ tions grant, administered by the Royal Society, greatly facilitated this work. REFERENCES
S. M. (1975). Anthostomella Sacco Part I. Mycological Papers 139, 1--97. DENNIS, R. W. G. (1964). The fungi of the Isle of Rhum, Kezo Bulletin 19,77-131. FRANCIS,
NOMENCLATURE OF ALBUGO TRAGOPOGONIS (PERS.) S. F. GRAY J. M. WHIPPS AND R. C. COOKE Department of Botany, University of Sheffield, U.K. Albugo tragopogonis on the leaves of Senecio squalidus L. has been used in several studies on the
physiology of host-biotroph relationships (Thornton & Cooke, 1970; Long & Cooke, 1974; Long, Fung, McGee, Cooke & Lewis, 1975; Whipps, 1977). During these investigations it was found that the literature on Albugo contains numerous confusions with respect to nomenclature. Such difficulties arise from inconsistencies in the use of the names Albugo and Cystopus for the same genus, and from lack of certainty as to the status of a number of 'species' within Albugo. The purpose of this note is to briefly explain and confirm the generic name Albugo, reasons for the use of which are not widely appreciated, and to establish the correct name for that Albugo species which is found on Senecio squalidus. Wider issues concerning the validity of criteria currently being used to divide Albugo at the specific and varietal level will be discussed in a further paper which deals with the development of Albugo species on susceptible and non-susceptible hosts (Whipps & Cooke, in prep.). Leveille (1847) transferred the names of some of Trans. Br. mycol, Soc. 70 (2) (1978).
Persoon's (1801) Uredo species to a new genus Cystopus. At that time the perfect state of this genus was unknown but upon its discovery by de Bary (1862, 1863) the sexual stage was firmly associated with the name Cystopus. However, prior to 1847, Albugo had been used on a number of occasions during the renaming of those Uredo species subsequently placed by Leveille in Cystopus (Roussel, 1806; Gray, 1821). Accordingly, Kuntze (1891) revived Albugo on the grounds of priority, a decision which was endorsed by later workers (Schroeter, 1893; Wilson, 1907; Fitzpatrick, 1930). The ensuing Albugo-Cystopus confusion came about through varying interpretations of Article 59 of the International Code of Botanical Nomenclature which, before 1956, stated that where a species possessed two or more morphologically distinct reproductive stages, then the name of the perfect state must take preference. Although the wording of the Article might have allowed exemption for the phycomycetes, particularly oomycetes, it was strictly adhered to by some mycologists (Ramsbottom, 1916; Wakefield, 1927; Novotel'Nova & Minasyan, 1970). Article 59 was designed
Printed in Great Britain
Printed in Great Britain
NOTES AND BRIEF ARTICLES ANTHOSTOMELLA ON PINE NEEDLES IN SCOTLAND SHEILA M. FRANCIS
Commonwealth Mycological Institute, Kew
Four species of Anthostomella Sacco have been recorded on Pinus in Europe (Francis, 1975). These fungi are rarely collected and few exsiccati have been found in herbaria. Only one of the Pinus species, A. formosa Kirschst., has been recorded for this country and it was known only from a culture sent to this Institute in 1971 by Dr C. S. Millar of Aberdeen University. He had isolated the fungus from first-year needles, green and apparently healthy, of Corsican pine (Pinus nigra var. maritima (Aiton) Melville) from Culbin Forest, Moray, Scotland. At the Aberdeen foray in September 1975 I collected a quantity of fallen needles of Corsican pine from the litter beneath the trees from which the isolations had been made. Prolonged searching of many hundreds of needles eventually produced six which yielded between them about twenty perithecia of A. formosa. This very low proportion of perithecia present in the litter continued in later collections sent to me from Culbin and agrees with the experience of Dr Millar and his colleagues. In 1975 Dr Millar showed me some needles of Pinus sylvestris from the island of Rhum in the Inner Hebrides with perithecia of an Anthostomella sp., identified as such by Dr S. C. Gregory of the Forestry Commission, Roslin, Midlothian. This proved to be A. pedemontana Ferr. & Sacc., known previously only from northern Italy and West Pakistan. I was able to visit Rhum and the neighbouring island of Canna in August 1976 and collected fallen needles of both Corsican and Scots pine. These yielded, in later examination, abundant material of the four European species of Anthostomella and, in addition from Canna, a species that closely resembled A. sabinianae S. Francis, a taxon described on needles of the Digger pine, Pinus sabiniana, from California (Francis, 1975), i.e. all the species ever recorded on Pinus. Descriptions of these fungi have already been given (Francis, 1975). Only the more important details are included in Table 1, and the spores are illustrated in Fig. 1. The collections of A. formosa and A. pedemontana agreed closely with the type material; those of A. conorum and A. sabinianae differed slightly. The type material of A. conorum was collected on cone scales of Scots pine and the
three other collections at Herb. K and IMI that I have seen were also on cone scales. A clypeus was present in these examples. No clypeus was seen in sections of needles of the Rhum material. A similar difference existed between the type material of A. sabinianae from California and the Canna collection. In the Californian specimens, on needles of Digger pine, there was a conspicuous circular clypeus which is absent in the Canna material on Corsican pine. There appear to be no obvious anatomical features in the pine needles to account for this difference. It should be noted that it is unusual for the species on pine needles to have a clypeus and the type material of A. sabinianae is the only collection I have seen with a clypeus. If this difference is maintained in subsequent collections I think the taxa should be separated at least at varietal level but I do not wish to do so on one collection. I hope to get further material from the Small Isles and west coast of Scotland and would be most grateful for the loan or gift of any other collections. It is obvious that the damp, relatively mild climate of Rhum and Canna is more favourable to the growth of these fungi than the much dryer and colder weather conditions prevailing at Culbin on the east coast. What is surprising is to find this range of species present especially on two islands where there are few mature trees, all of which have been planted this century. Dennis (1964) in his study of 'The Fungi of the Isle of Rhum' first made this general point stating that 'The usual mycorrhizal fungi, parasites and saprophytes have accompanied or followed their hosts in these isolated tree plantings ... to a remarkable degree.' On Rhum the mature trees cluster round Kinloch Castle at the head of Loch Scresort and also form a thin line along the south shore of the loch. My collections on Rhum were made from litter beneath Corsican pine immediately behind the jetty (site LS); from Scots pine in the Deer reserve to the west of the Castle (DR); and a to-year-old stand of Scots pine 3 miles west of the Castle in the Kilmory plots (KP). On Canna the oldest trees are a stand of Corsican pine on Compass Hill planted 70 years ago. The four trees of Scots pine which are adjacent to the Corsican pine are 5-7
Notes and brief articles
c
R
A
[)
20//111
Fig. 1. Ascospores of (A) Anthostomella conorum (IMI 208976e), (B) A. formosa (IMI 197142), (C) A. pedemontana (IMI 214112), (D) A. sabinianae (IMI 208976d).
Table
1.
Diagnostic characters of Anthostomella species found on Pinus Ascospores ~--------"----~-------,
Germ
Asci (pm) A. conorum (Fckl) Sacc.*
96-140 x 10-13
Size (pm) 13-17 x 7-9
Cell no. 1
slit (pm) = length
of spore A.formosa Kirschst, A. pedemontana Ferr. & Sacc.* A. sabinianae S. Francis*
120-135 x 8 110-113 X 9-12 111-133 X 8-10
13'5-15"5 x 6-7 13-16 x 6-7 14-15 x 6-7
2 1 2
7- 1 0 6 = length of spore
Sheath
+ + + +
* Denotes a new record for Britain.
years old and came originally from Rhum. The distribution of species of Anthostomella as shown by these collections is given in Table 2. I visited Rhum and Canna again in 1977 and made further collections. The results from Rhum were similar to those reported for 1976. Fallen cones of Pinus nigra were examined for A. conorum without success although the fungus was present on fallen needles at this site. A sample of cones and needles collected in June by Dr David Minter gave the same result. Trans. Br. mycol. Soc. 70 (2) (1978).
Collections at Canna were made at the edge of the Corsican pine wood on Compass Hill (1976 collections came from the centre of the wood). The fallen needles again yielded A. sabinianae without a clypeus but in addition, on this occasion, specimens of the fungus were found with a distinct, well-defined dypeus which appeared exactly similar to the Californian material. The most obvious difference between the two sites is that the edge of the wood is warm and sunny while the centre is nearly devoid of sun and appreciably
Printed in Great Britain
Notes and briefarticles Table
2.
Location of Anthostomella spp. on Rhum and Canna
A. conorum
Ai formosa
A. pedemontana
A. sabinianae
Rhum P. syluestris
+
Site DR Site KP
+
P. nigra
Site LS
+
+
+
+
Canna P. syluestris
P. nigra
cooler even when visited on an exceedingly hot day in the summer of 1976. It is a pleasure to acknowledge the help I have had from Dr Colin Millar. I thank the Nature Conservancy for allowing me to collect on Rhum and the Chief Warden, Peter Corkhill, for his assistance; Dr and Mrs J. Lome Campbell for permission to land and collect on Canna and for their kind hospitality to my husband and me. The loan of a microscope from the Scientific Investiga-
+ tions grant, administered by the Royal Society, greatly facilitated this work. REFERENCES
S. M. (1975). Anthostomella Sacco Part I. Mycological Papers 139, 1--97. DENNIS, R. W. G. (1964). The fungi of the Isle of Rhum, Kezo Bulletin 19,77-131. FRANCIS,
NOMENCLATURE OF ALBUGO TRAGOPOGONIS (PERS.) S. F. GRAY J. M. WHIPPS AND R. C. COOKE Department of Botany, University of Sheffield, U.K. Albugo tragopogonis on the leaves of Senecio squalidus L. has been used in several studies on the
physiology of host-biotroph relationships (Thornton & Cooke, 1970; Long & Cooke, 1974; Long, Fung, McGee, Cooke & Lewis, 1975; Whipps, 1977). During these investigations it was found that the literature on Albugo contains numerous confusions with respect to nomenclature. Such difficulties arise from inconsistencies in the use of the names Albugo and Cystopus for the same genus, and from lack of certainty as to the status of a number of 'species' within Albugo. The purpose of this note is to briefly explain and confirm the generic name Albugo, reasons for the use of which are not widely appreciated, and to establish the correct name for that Albugo species which is found on Senecio squalidus. Wider issues concerning the validity of criteria currently being used to divide Albugo at the specific and varietal level will be discussed in a further paper which deals with the development of Albugo species on susceptible and non-susceptible hosts (Whipps & Cooke, in prep.). Leveille (1847) transferred the names of some of Trans. Br. mycol, Soc. 70 (2) (1978).
Persoon's (1801) Uredo species to a new genus Cystopus. At that time the perfect state of this genus was unknown but upon its discovery by de Bary (1862, 1863) the sexual stage was firmly associated with the name Cystopus. However, prior to 1847, Albugo had been used on a number of occasions during the renaming of those Uredo species subsequently placed by Leveille in Cystopus (Roussel, 1806; Gray, 1821). Accordingly, Kuntze (1891) revived Albugo on the grounds of priority, a decision which was endorsed by later workers (Schroeter, 1893; Wilson, 1907; Fitzpatrick, 1930). The ensuing Albugo-Cystopus confusion came about through varying interpretations of Article 59 of the International Code of Botanical Nomenclature which, before 1956, stated that where a species possessed two or more morphologically distinct reproductive stages, then the name of the perfect state must take preference. Although the wording of the Article might have allowed exemption for the phycomycetes, particularly oomycetes, it was strictly adhered to by some mycologists (Ramsbottom, 1916; Wakefield, 1927; Novotel'Nova & Minasyan, 1970). Article 59 was designed
Printed in Great Britain