Taxonomic Review of and Development of a Lucid Key for Philippine Cercosporoids and Related Fungi

The genus Mycosphaerella Johanson, contains more than 3000 names (Aptroot 2006), and has been linked to more than 30 well-known anamorphic genera (Crous 2006a and 2006b). It has a worldwide distribution from tropical and subtropical to warm and cool regions (Crous 1998; Crous et al. 2000 and 2001). Mycosphaerella, however, has been associated with at least 27 different coelomycete or hyphomycete anamorph genera (Kendrick and DiCosmo, 1979), 23 of which were accepted by Crous et al. (2000). More than 3000 names have already been published in Cercospora (Pollack, 1987). The genus Cercospora Fresen., which is one of the largest genera of hyphomycetes, has been linked to Mycosphaerella teleomorphs (Crous et al., 2000). Cercospora was first monographed by Chupp (1954), who accepted 1419 species. Subsequent workers such as, F.C. Deighton, B.C. Sutton and U. Braun divided Cercospora in to almost 50 different genera which are morphologically similar and distinct with each other (Crous and Braun, 2003).


Status of collection
; ; ; Guo et al. (1998);; Saccardo (1886); Shin & Kim (2001); . * AR= already reported, FR= first record. Some former species of Cercospora that are morphologically different from C.apii s.lat., are now considered to Cercospora s.str. As far as known, Cercospora s.str. are host specific or with a host range confined to species of a single host genus or some allied host genera of a single family. This phenomenon is constantly being addressed via molecular studies (Crous et al., 2000(Crous et al., , 2001 olivaceous brown conidiophores with small conspicuously thickened and darkened conidiogenous loci, and obclavate-cylindrical conidia with obconically truncate base (Table 2). Teodoro (1937) had enumerated 65 species of Cercospora in the Philippines while 33 species were reported by Quimio and Abilay (1977). In the present study, 48 hosts exhibiting leaf spots were reported as caused by species of Cercospora, 32 were from medicinal plants. There were 30 first records of Cercospora leaf spots recorded in this study. All species of Cercospora associated with those hosts are known except for a species on Basella albae. It has not been described on this host; therefore, it warrants description on a new host record, with proposed species name of Cercospora basellae-albae (Begum and Cumagun, 2010).
Stromata lacking to well developed, usually pigmented; conidiophores are pigmented, pale olivaceous to medium dark brown with conidiogenous loci inconspicuous, unthickened and not darkened but somewhat refractive or rarely very slightly darkened, or only outer rim slightly darkened and refractive; conidia subhyaline to pigmented, solitary or catenulate, scolecosporous, hila unthickened and not darkened (Table 3). Pseudocercospora was introduced by Spegazzini (1910). Deighton (1976) re-introduced this name and widened the concept of this genus considerably to include a wide range of cercosporoids with pigmented conidiophores and inconspicuous, unthickened, not darkened conidiogenous loci. It is the second largest Cercosporoid genus, with more than 300 published names (Kirk et al. 2001). In Taiwan, 198 species of Pseudocercospora have been recognized by . In the present study, 20 Pseudocercospora sp. were reported, of which 14 species caused diseases on medicinal plants (Table 3). There were 12 new records of Pseudocercospora diseases in the Philippines.

Dichotomous Key to the Species Passalora
Bougainvilla, (Ponaya & Cumagun, 2008), P. henningsii on Manihot esculenta, formerly named as Cercospora cassavae Ellis & Everh. /C. manihots Henn. / C. henningsii Allesch (Crous and Braun, 2003) and P. tinosporae on Tinospora reticulate. The same host species and the associated fungi were reviewed in the study and were found to confirm with the descriptions of the genus Passalora (Table 4).
Stromata none; conidiophores macronematous, mononematous, each composed of an erect, straight or flexious, brown to dark blackish brown, smooth or verruculose; conidiogenous cells polyblastic, integrated and terminal, sympodial, cylindrical, scars often numerous; Conidia solitary or occasionally in very short chains, simple, ellipsoidal, obclavate or obovoid, hyaline or rather pale olive or olivaceous brown, without septa or with one or a few transverse septa.
In the present study, only one Periconiella lygodii on Lygodium japonicum was reported (Table 6). Four species of Periconiella have been reported to occur on ferns (Braun, 2004). He noted that P.lygodii is distinguished from all other species of Periconiella on ferns by having long, obclavate-cylindrical, pluriseptate, smooth conidia. This is the first record of P. lygodii on Lygodium japonicum in the Philippines, (Begum et al. 2009).

Lucid key for Philippine cercosporoid fungi
Before the advent of computers, the traditional way in which scientists identify identify biological specimens was through the use of printed pathway (or dichotomous) keys. However, with the advent of database and multi-media-software, it is now possible to store large amounts of biological data and to access this information through easy-to-use matrixbased (or multi-access) keys. Lucid is one example of a multi-media matrix key.The Lucid Program from The Centre for Biological Information Technology CBIT, University of Queensland, which was licensed to the third author was used to develop the Lucid key. The activities involved in the process of designing, developing, producing and publishing a Lucid key on CD, DVD or the Internet are outlined as follows: (1) Establishing the scope of the key; (2) designing and scoring the key; (3) sourcing, developing and editing facts sheets, images and other multi-media associated with features and entities; (4) packaging up a prototype on CD or on the Internet; (5) beta testing and user testing of the key; (6) graphic design of CD and CD-insert or web; and (7) packing of key for release.

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Taxonomic Review of and Development of a Lucid Key for Philippine Cercosporoids and Related Fungi 33

Lucid Builder
Lucid key consists of two programs: Lucid Builder and Lucid Player. The first program is a key development tool (Fig. 1) that allows taxonomists to input their knowledge base into a form that is readily accessible by other people. A Lucid Builder enables key developers to easily build their own keys. In the present study, information from 74 Cercosporoid fungi data were entered for developed Lucid key. In Lucid Builder, data were incorporated for example for Cercospora adiantigena on Adiantum phillipense (Fig. 2). The right side of the screen shows, all species that were inputted while left side provides the inputted characters for specific species. The information that were entered on the left side of the screen corresponds to the highlighted Cercosporoid species on the right side.
www.intechopen.com During an identification session, Lucid Player allows one to choose any question in its list at any time, but "stepping" through the key in a structured and sensible way will make one task of identification easier. The guidelines for making identification are as follows (1) familiarity with the specimen; (2) note and use of distinctive features; (3) answering easy features first; 4) choosing multiple states; and (5) checking the result.
Familiarity with the characteristics of the specimen to be identified is essential. Briefly reviewing Lucid key and specimen's characteristics before one starts will facilitate the identification. In any key, some taxa may possess particularly distinctive features. Use of these may allow the taxon to be keyed out in a very few steps. At the very least, starting with particularly distinctive or striking features for the first character states selected may quickly reduce the list of entities remaining. One can select any features from any position in the list and start by browsing the list of features available for obvious features that one can quite quickly answer, as opposed to getting stuck on the first one. Lucid is designed to overcome problems associated with difficult and obscure features.Always choose multiple states if one is uncertain which state is the correct one to choose for a particular specimen. One can choose as many states as from any one feature. After a preliminary identification has been made, one can check the other information (notes or image) provided for the taxon.

Lucid Player
The second program of the Lucid key is key interface or Lucid Player (Fig. 3) through which end-users interact with the Lucid key that has been developed and distributed either as a CD-Rom or via the Internet. The Lucid player enables users to view and interact with the key. Lucid Player allows one to input a list of character states that best describe the specimen to be identified. These character states can be selected (or de-selected) in any order, resulting in a shortening of the list of remaining taxa that best match the decribed specimen. The upper left side of the screen shows all characters for a given specimen while it's lower left side indicates the characters that were chosen. The upper right side of the screen provides the possible identity of the specimen while the lower right side shows the discarded taxa from the list (Fig. 4). In the present study, Lucid key was developed to identify Cercosporoid fungi, even though the dichotomous keys are the most common keys encountered. The use of dichotomous keys has a major disadvantage: if a couplet is difficult or impossible to answer, the identification session often ends there. Lucid has the advantage over printed dichotomous keys in that the user is able to skip an unanswerable couplet or question and still proceed with identification because Lucid key allows to start at any point and proceed in any order. Lucid guide for smut fungi of Australia has already been completed. Its accompanying CD, incorporating a Lucid Player, provides an easy-to-use, interactive key to smut species, with comprehensive fact-sheets, distribution maps, and over 1000 images (Vanky and Shivas, 2008). On the other hand, Lucid guide for smut fungi of Thailand is still underway in collaboration with Australian plant pathologists (Shivas, personal communication). Gerald (2005) reported that, "Diagnosing Postharvest Diseases of Cantaloupe" is the first Lucid key developed in the U.S. for a set of plant diseases and one of the first plant disease identification keys ever developed in Lucid. A Lucid key was developed for the identification of Phytophthora species in USA based on morphological and molecular characters (Ristaino et al. 2008 present study only the data of the true Cercosporoids like, Cercospora, Pseudocercospora and Passalora were inputted into the Lucid key.
Identification of Cercosporoid fungi is a difficult task, and the Lucid key was created to help provide individuals with easily accessible tools to distinguish species. Recent experience suggests that computer-based identification keys will become an increasingly important part of the move towards providing taxonomic information on-line.

Summary and conclusions
The genus Cercospora is one of the largest genera of hyphomycetes. i.e., commonly associated with leaf spots and is responsible for great damages to beneficial plants, such as cereals, vegetables, ornamentals, forest trees, grasses. A total of 105 Cercosporoid diseases were identified, belonging to Cercospora (48), Pseudocercospora (20), Passalora (5), Asperisporium (1), Cladosporium (30,) and Periconiella (1). From the reported Cercospora species, 20 were Cercospora apii s.lat and 28 were Cercospora s.str. The first report of Cercospora basellae-albae in the Philippines was observed causing leaf spots on Basella alba cv. Rubra (Begum and Cumagun, 2010). Twenty eight first records of Cercospora leaf spots were reported. Among Pseudocercospora leaf spots, 12 first records were reported and all were host specific. A new species of Passalora amaranthae found on Amaranthus viridis was reported. Only one specimen caused by Asperisporium moringae was reported on Moringa oleifera.
Lucid key is a powerful and highly flexible knowledge management software application designed to help users with identification and diagnostic tasks. Lucid is one of a multimedia matrix keys, that includes possible the storing of large amounts of information. Lucid key consists of two programs: Lucid Builder and Lucid Player. The first program is a key development tool, which allows developers to easily build their own keys. The second program of the Lucid key is the key interface or Lucid Player, through which end-users interacts with the Lucid key and enables users to view and interact with the key. In the present study, Lucid key was developed to identify Cercosporoid fungi, a total of 74 Cercosporoid fungi and their characters were entered into a program using Lucid Builder. Lucid has the advantage over printed dichotomous keys in that the user is able to skip an unanswerable couplet or question and still proceed with identification. Identification of Cercosporoid fungi is a difficult task, and the Lucid key was created to help provide individuals with easily accessible tools to distinguish species. The end product of the Lucid key of Philippine Cercosporoid fungi, in the future will be useful in teaching, research, and extension work in mycology and plant pathology.