Genetic variability and mycohost association of Ampelomyces quisqualis isolates inferred from phylogenetic analyses of ITS rDNA and actin gene sequences

Ampelomyces quisqualis complex is well known as the most common and widespread hyperparasite of the family Erysiphaceae, the cause of powdery mildew diseases. As commercial biopesticide products it is widely used to control the disease in field and plastic houses. Although genetic diversity within Ampelomyces isolates has been previously recognized, a single name A. quisqualis is still applied to all pycnidial intracellular hyperparasites of powdery mildew fungi. In this study, the phylogenetic relationships among Ampelomyces isolates originating from various powdery mildew fungi in Korea were inferred from Bayesian and maximum parsimony analyses of the sequences of ITS rDNA region and actin gene. In the phylogenetic trees, the Ampelomyces isolates could be divided into four distinct groups with high sequence divergences in both regions. The largest group, Clade 1, mostly accommodated Ampelomyces isolates originating from the mycohost Podosphaera spp. (sect. Sphaerotheca). Clade 2 comprised isolates from several genera of powdery mildews, Golovinomyces, Erysiphe (sect. Erysiphe), Arthrocladiella, and Phyllactinia, and was further divided into two subclades. An isolate obtained from Podosphaera (sect. Sphaerotheca) pannosa was clustered into Clade 3, with those from powdery mildews infecting rosaceous hosts. The mycohosts of Ampelomyces isolates in Clade 4 mostly consisted of species of Erysiphe (sect. Erysiphe, sect. Microsphaera, and sect. Uncinula). The present phylogenetic study demonstrates that Ampelomyces hyperparasite is indeed an assemblage of several distinct lineages rather than a sole species. Although the correlation between Ampelomyces isolates and their mycohosts is not obviously clear, the isolates show not only some degree of host specialization but also adaptation to their mycohosts during the evolution of the hyperparasite.     

Natural occurrence of ampelomyces intracellular mycoparasites in mycelia of powdery mildew fungi

This is the first extensive investigation that quantifies natural mycoparasitic relationships in the phyllosphere. The presence of Ampelomyces spp. was quantified in naturally occurring powdery mildew fungi collected in Hungary and Romania between 1992 and 1995. A total of 570 samples was studied representing 27 species (nine genera) of the Erysiphaceae infecting 41 host plant genera. The incidence of Ampelomyces spp., determined as the proportion of samples in which intracellular pycnidia were present, varied between 4.3 and 68.8% in the host fungal genera studied. The intensity of mycoparasitism, defined as a percentage of the powdery mildew mycelia parasitized by Ampelomyces , ranged from 0.15 to 65%. Both the incidence and the intensity of mycoparasitism showed the lowest values in Blumeria graminis (DC.) Speer collected from wild and cultivated monocotyledons, while the highest values were found in Arthrocladiella mougeotii (Lév.) Vassilkov infecting Lycium halimifolium Mill. plants. The paper reports for the first time the natural occurrence of Ampelomyces in Sawadaea bicornis (Wallr.:Fr.) Homma on maple.     

Hyperparasites of the genus shape Ampelomyces on powdery mildew fungi in Serbia

From 1982 to 1996, in Serbia, 229 species of plants infected with powdery mildew were collected. Seventy-five species had hyperparasites of the genus Ampelomyces. Distribution analysis showed that hyperparasitism was greatest on plants from the families Asteraceae, Apiaceae and Fabaceae. Ampelomyces was not found on the family Poaceae. It was reported for the first time on the families Amygdalaceae, Cornaceae, Grossulariaceae, Plantaginaceae, Rhamnaceae and other 37 plant species. Hyperparasites of the genus Ampelomyces were found on 33 different species of fungi that are causal agents of powdery mildews. They are reported for the first time on nine species. Pycnidial size varied in the range 45–106 × 25.5–40.5 μm and conidia from 4.5–10.5 × 2.5–4.8 μm. This revised version was published online in June 2006 with corrections to the Cover Date.     

Phoma glomerata as a mycoparasite of powdery mildew

Ampelomyces and Phoma species are frequently confused with each other. Isolates previously attributed to the genus Ampelomyces were shown to be Phoma isolates through studies of their morphology and life cycle and ribosomal DNA internal transcribed spacer region 1 sequence analysis. Phoma glomerata can colonize and suppress development of powdery mildew on oak and may have utility as a mycoparasitic agent.     

Corrigendum

New Phytologist 144 (1999), 195–202
In the October 1999 issue of New Phytologist , we published the research paper entitled 'Identification and expression analysis of two fungal cDNAs regulated by ectomycorrhiza and fruit body formation' by Uwe Nehls et al . ( New Phytol . (1999) 144 , 195–202). Since its publication, the authors have identified an important error in Fig. 4: the labels SC13 and SC25 are in incorrect positions and should be transposed.
We apologise to our readers for this mistake.     

The New Phytologist Forum

New Phytologist has, throughout its history, been a forum for open debate – indeed, in his opening editorial (1902), Tansley referred to 'easy communication and discussion' as being the main ideas for the journal launch. The Internet now offers exciting new ways for sharing information, and this has challenged all information providers to reassess what they offer. It is our intention that the new Forum section in the journal should formalize our standing commitment, and encourage serious dialogue – through scientific commentary, correspondence and opinion.
As the journal approaches its hundredth year, so the need for dialogue is stronger than ever. More and more science is published, making it harder, year on year, to keep abreast of important developments. Science is also global, making discussion confined to those within one country or economic bloc to be too restrictive. And as the pressure to publish is as strong as it has ever been, so the free flow of original and unorthodox ideas can too easily become stifled.
New Phytologist , as a high-impact, high-quality journal, with its international scope and fierce independence – the Trust is not answerable to any society or commercial publisher – is a respected vehicle for such material. We invite you to participate, and to join us in helping the Forum to develop.     

金银忍冬白粉菌及其重寄生菌的报道

通过对来自中国青岛金银忍冬的调查,发现一中国新记录种——金银忍冬白粉菌(Erysiphe caprifoli-acearum var. caprifoliacearum)并在其上首次发现重寄生菌——白粉寄生孢(Ampelomyces quisqualis)。根据采集的材料对其进行了详细的形态描述和显微拍照。研究标本保存于青岛农业大学真菌标本室(HMQAU)。     

Ampelomyces quisqualis Ces., ein Parasit auf Mucorineen

Zusammenfassung Ampelomyces quisqualis Ces., ein bisher für Mucorineae noch unbekannter Parasit, wurde in seiner Entwicklung und seinem Befallsbild untersucht. Neun Gattungen der Mucoraceae und vier Gattungen anderer Mucorineen-Familien wurden durch Infektionsversuche auf Agar-Platten (Ausnahme Actinomucor) getestet. Bei allen wurde eine meist starke Schädigung festgestellt. Nur die Sektion Pusilla der Gattung Mortierella war weitgehend resistent. Im einzelnen sei als Folge des Befalls hingewiesen auf das Auftreten homothallischer Zygoten bei Absidia glauca, auf die Bildung von Zwergsporangien bei Phycomyces und auf die Pilaira-artige Ausbildung des Sporangienträgers bei Pilobolus.

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Ampelomyces quisqualis Ces., a Parasite on Mucorineae

Summary Ampelomyces quisqualis Ces., an hitherto unknown parasite on Mucorineae, is described in its development and its growth on the hosts. 9 genera of Mucoraceae and 4 genera of other families of Mucorineae were tested as potential hosts for Ampelomyces quisqualis on malt-agarplates. A violent damage to most species was found. Only the sectio Pusilla of the genus Mortierella was rather resitent. As sequence to the attack homothallic zygospores appeared in Absidia glauca, dwarfish sporangia in Phycomyces, and the sporangiophores of Pilobolus became similar in appearance to the sporangiophores of Pilaira.

     

Errata

New Phytologist 145 (2000), 1–3
In the January 2000 issue of New Phytologist , we published the forum article entitled 'Cadmium for all meals – plants with an unusual appetite' by U. Krämer. Since its publication, it has been brought to our attention that an error was introduced during typesetting. In the text several instances of concentrations are erroneously presented as mg⁻¹: these should be kg mg⁻¹.
New Phytologist 145 (2000), 367–421
In the March 2000 issue of New Phytologist , we published the Tansley review entitled 'Numerical and physical properties of orchid seeds and their biological implications' by J. Arditti and A. K. A. Ghani. Since its publication, it has been brought to our attention that an error was introduced during typesetting. On p. 391, Eqn 5, the horizontal line above the right side of the equation should form a square root sign.
We apologize to the authors and to our readers for these mistakes.     

Activity of natural products against courgette powdery mildew

The effectiveness of several natural products in field trials were tested against powdery mildew on courgette. Sulphur, sodium bicarbonate (alone or in mixture with pinolene, mineral oil or sulphur), sodium silicate in mixture with mineral oil, potassium permanganate, lecithin, Equisetum arvense in mixture with Timus vulgaris, Ampelomyces quisqualis and Reynoutria sachalinensis were evaluated. Generally, in our working conditions (very strong pathogen infection), only some products were effective. Good results were obtained using sulphur and potassium permanganate in the first year and very interesting results about disease control were obtained, in the second year of the trial, using sulphur alone or in mixture with sodium bicarbonate. The products tested did not show any phytotoxic symptoms.     

一株白粉寄生菌的酚类代谢产物

从得自鼎湖山自然保护区的一株白粉寄生菌(Ampelomyces sp.)SC0307固体发酵物中分离得到7个酚类化合物.通过波谱分析,分别鉴定为2,5-二羟基苯甲醇(1)、对羟基苯甲酸(2)、2,5-二羟基苯甲酸(3)、3,4-二羟基苯甲酸(4)、苯乙酸(5)、3,4-二甲氧基肉桂酸(6)、3,4,5-三甲氧基肉佳酸(7).7个化合物均为从白粉寄生菌属真菌中首次分离获得.     

Mycoparasite-Ampelomyces in artificial culture I. Morphology and cultural behaviour

This paper reports detailed studies and observations made on five isolates of the common mycoparasite on powdery mildews viz.Ampelomyces quisqualis Ces. in artificial culture. The results revealed some significant variations among these isolates in respect of morphological characters of pycnidia and pycnidiospores and colony characters, which provide evidence on the existence of physiologic forms within this species of the hyperparasite.     

Models of natural mutations including site heterogeneity

New computational models of natural site mutations are developed that account for the different selective pressures acting on different locations in the protein. The number of adjustable parameters is greatly reduced by basing the models on the underlying physical-chemical properties of the amino acids. This allows us to use our method on small data sets built of specific protein types. We demonstrate that with this approach we can represent the evolutionary patterns in HIV envelope proteins far better than with more traditional methods. Proteins 32:289–295, 1998. © 1998 Wiley-Liss, Inc.     

New Phytologist 140 (1998), 363–383

In the November 1998 issue of New Phytologist , we published the Tansley review 'Gibberellins: regulating genes and germination' by Sian Ritchie and Simon Gilroy ( New Phytol. (1998) 140 , 363–383). Since its publication, it has come to our attention that text associated with Fig. 4 was omitted during production. The correct figure is reprinted here in full.
We apologise to the author and to our readers for this mistake.
Figure 4. Promoter sequences of various genes expressed in the cereal aleurone and shown to be regulated by GA. The position of each sequence is indicated relative to the start codon. Regions identified as being involved in regulation of the genes are highlighted, as are similar regions in other genes. Sites at which protein has been shown to bind are also indicated. ( a ) Barley Amy 32b (Sutcliff et al ., 1993; Whittier et al ., 1987); wheat Amy 2/54 (Huttley et al ., 1992; Rushton et al ., 1992; Rushton et al ., 1995); barley Amy 46 (Khursheed & Rogers, 1988); barley Amy 2/p155 (Knox et al ., 1987); barley aleurain (Whittier et al ., 1987); barley β-glucanase II (Wolf, 1992); wheat cathepsin B-like (Cejudo et al ., 1992); rice ubiquitin-conjugating enzyme (Chen et al ., 1995). ( b ). Wheat Amy 1/18 (Rushton et al ., 1992); barley Amy pHV 19 (Jacobsen & Close, 1991; Gubler & Jacobsen, 1992)/ Amy 1 / 6-4 (Khursheed & Rogers, 1988; Rogers, Lanahan & Rogers 1994); rice OSamy-a / Amy 3c (Ou-Lee et al ., 1988; Sutcliff et al ., 1991; Yu et al ., 1992; Goldman et al ., 1994); rice Amy 3B (Sutcliffe et al ., 1991); rice OSamy-c (Kim et al ., 1992; Kim & Wu, 1992; Tanida et al ., 1994); rice Amy 1A (Huang et al ., 1990; Itoh et al ., 1995).
Figure 4 ( b ). For legend see facing page.     

白粉寄生孢ISSR-PCR体系的建立及遗传多样性的初步分析

通过正交设计和单因素水平优化的方法对白粉寄生孢ISSR-PCR程序中的一些反应参数和ISSR引物进行优化和筛选,并利用建立的ISSR-PCR的反应体系来分析白粉寄生孢的遗传多样性。5个ISSR引物对73个菌株的扩增条带表明,ISSR标记在中国白粉寄生孢中存在较高的多态性,ISSR标记揭示白粉寄生孢的遗传多样性和寄主植物(真菌)多样性存在一定的相关性。     

Testing a new Monte Carlo algorithm for protein folding

We demonstrate that the recently proposed pruned-enriched Rosenbluth method (PERM) (Grassberger, Phys. Rev. E 56:3682, 1997) leads to extremely efficient algorithms for the folding of simple model proteins. We test it on several models for lattice heteropolymers, and compare it to published Monte Carlo studies of the properties of particular sequences. In all cases our method is faster than the previous ones, and in several cases we find new minimal energy states. In addition to producing more reliable candidates for ground states, our method gives detailed information about the thermal spectrum and thus allows one to analyze thermodynamic aspects of the folding behavior of arbitrary sequences. Proteins 32:52–66, 1998. © 1998 Wiley-Liss, Inc.     

香薷白粉病菌及其重寄生菌的分离鉴定

对采自中国长春香薷白粉病菌进行系统观察和测量,鉴定其为本间白粉菌(Erysiphe hommae Braun),同时发现了重寄生菌——白粉寄生孢（Ampelomyces quisqualis Ces.）,并对重寄生茵的叶部寄生特征及培养特征进行了描述.室内检测结果表明,重寄生菌的重寄生强度较高,可抑制白粉病的发生.     

On the phylogenetic position of the New Caledonian endemic families Paracryphiaceae, Oncothecaceae, and Strasburgeriaceae: A comparison of molecules and morphology

Following his collecting trips to New Caledonia in 1979 and 1981, William C. Dickison published a series of papers focused on the anatomy, morphology, and systematic relationships of the monogeneric, endemic families Strasburgeriaceae, Oncothecaceae, and Paracryphiaceae. He and his collaborators concluded thatParacryphia, Oncotheca, andStrasburgeria should each be treated as distinct families positioned near Sphenostemonaceae, Theaceae, and Ochnaceae, respectively. These anatomical data proved to be a valuable source of systematic characters, but the precise phylogenetic positions of these enigmatic families continue to be in doubt. In fact, even the ordinal classification of flowering plants published by the Angiosperm Phylogeny Group (APG, 1998) left uncertain the position of two of these three families. More recently, however, phylogenies for eudicots based on multiple-gene data sets firmly place Oncothecaceae within Garryales, a position that has never been suggested previously. In the case of Paracryphiaceae, molecular data support the most often cited, historical placement of the family within Dipsacales. New molecular data presented here support the position of Strasburgeriaceae as sister to Ixerbaceae within Crossosomatales. This is one of several historical placements suggested for the family, but a placement that has not been cited in recent years. A comparison of anatomy/morphology betweenStrasburgeria andIxerba is presented in the context of this molecular phylogenetic hypothesis.     

Understanding the industrial application potential of lactic acid bacteria through genomics

Lactic acid bacteria (LAB) are a heterogeneous group of bacteria contributing to various industrial applications, ranging from food and beverage fermentation, bulk and fine chemicals production to pharmaceuticals manufacturing. Genome sequencing is booming; hitherto, 25 genomes of LAB have been published and many more are in progress. Based on genomic content of LAB, this review highlights some findings related to applications revealed by genomics and functional genomics analyses. Finally, this review summarizes mathematical modeling strategies of LAB in the context of genomics, to further our understanding of industrial related features.