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Ravenelia is the third largest rust genus of the order Pucciniales with more than 200 described species. It is an important rust genus that has undergone tremendous taxonomic changes. This genus produces teliospores united into a head on a compound pedicel composed of two to several hyphae with autoecious, macro-, demi- to hemi-, and, more rarely, microcyclic modes of their life cycle which provide it a unique identity and have proved helpful in the identification of the genus. The current understanding of the taxonomy, history, diversity and distribution of this genus is discussed in this paper. Both online and offline resources were searched to gather data of the published literature. The data thus obtained were analyzed for numerical and graphical summaries to provide the diversity and distribution of the genus. In addition, a phylogenetic analysis based on the ITS and nLSU DNA sequence data available in GenBank and the published literature was performed to examine the taxonomic placement of different species within the genus. The genus was reported to be distributed over 53 countries of the world. Around 51 plant genera belonging to four plant families, viz., Fabaceae, Phyllanthaceae, Asphodelaceae and Zygophyllaceae were found to be infected with these rust fungi. The phylogenetic analysis based on LSU and ITS sequence data revealed the polyphyletic nature of the genus. A table of 248 species of this genus is also provided with all information of host, distribution and cited reference that can be helpful for mycologists to find all information at one place. Future perspectives for the advancement of this genus are also discussed.

Puccinia, which comprises 4000 species, is the largest genus of rust fungi and one of the destructive plant pathogenic rust genera that are reported to infect both agricultural and nonagricultural plants with severe illnesses. The presence of bi-celled teliospores is one of the major features of these rust fungi that differentiated them from Uromyces, which is another largest genus of rust fungi. In the present study, an overview of the current knowledge on the general taxonomy and ecology of the rust genus Puccinia is presented. The status of the molecular identification of this genus along with updated species numbers and their current statuses in the 21st century are also presented, in addition to their threats to both agricultural and nonagricultural plants. Furthermore, a phylogenetic analysis based on ITS and LSU DNA sequence data available in GenBank and the published literature was performed to examine the intergeneric relationships of Puccinia. The obtained results revealed the worldwide distribution of Puccinia. Compared with other nations, a reasonable increase in research publications over the current century was demonstrated in Asian countries. The plant families Asteraceae and Poaceae were observed as the most infected in the 21st century. The phylogenetic studies of the LSU and ITS sequence data revealed the polyphyletic nature of Puccinia. In addition, the presences of too short, too lengthy, and incomplete sequences in the NCBI database demonstrate the need for extensive DNA-based analyses for a better understanding of the taxonomic placement of Puccinia.

The rust genus Skierka belonging to the phylum Basidiomycota was described in 1900 by Raciborski with Skierka canarii as the type species. The published literature on this rust genus reveals its ambiguity in taxonomic placement. It was challenging to taxonomically delineate and precisely identify each species within this genus due to the species sharing some common characteristics. The latest studies based on morphology taxonomy and molecular characteristics, however, have solved this puzzle now and placed this genus in its new family Skierkaceae. To understand all about the genus Skierka, this compilation was carried out to unveil the general characteristics, history, diversity, distribution, ecology, morphology and molecular taxonomy of different species of Skierka. After exploring 14 species of Skierka, it was observed that this genus is distributed in seven plant families in 19 countries all over the world. The genus appears to be well-represented in Asian and South American counties. This rust has not been reported from any European countries to date. The morpho-taxonomy of all species is well studied, but molecular analyses are still required. Only two species of the genus namely S. robusta and S. diploglottidis were identified based molecular analyses. Therefore, further studies should be focused on epitypifying the taxa that are too old and updating their taxonomy based on molecular, biochemical, and physiological aspects along with morphological characteristics. Multiple analytical methods should be considered when dealing with multi-locus datasets. This will increase our understanding of the diversity, distribution, and identification of these rust fungi.

An updated analysis of the diversity of rust fungi in Himachal Pradesh is provided herein as a product of field surveys, of mycological analysis, and of all forms of published documentation and literature. The results of all forms of analysis revealed that Himachal Pradesh has 167 species of rust fungi belonging to the class Pucciniomycetes. The class is represented by 11 families, 23 genera with 167 species. The Pucciniaceae (96 species) followed by Phragmidiaceae (14 species) are the largest families of rust fungi reported from the state. Rest of the families were found associated with 1–10 species of rust fungi. The rust fungi (19 species) with uncertain placement are placed in incertae sedis. The rust genera reported from Himachal Pradesh so far are Aecidium, Chrysomyxa, Coleosporium, Frommea, Gymnosporangium, Kuehneola, Kweilingia, Melampsora, Monosporidium, Ochrospora, Peridermium, Phakopsora, Phragmidium, Pileolaria, Puccinia, Pucciniastrum, Pucciniostele, Ravenelia, Skierka, Uredinopsis, Uredo, Urocystis, and Uromyces.

Uromyces is the second-largest plant pathogenic rust genus, is responsible for numerous diseases, and has major effects on both agricultural and non-agricultural plants. The genus is generally characterized by its unicellular teliospores that help to characterize it and distinguish it from another important rust genus, Puccinia. In this study, a global overview of the diversity and distribution of Uromyces is presented based on both online and offline resources. The information obtained was analyzed for numerical and graphical summaries to provide the diversity and distribution of the genus by country and continent. Besides this, broad taxonomical aspects, a brief life cycle, and other comparative aspects on diversity and distribution were also provided. In addition, a phylogenetic analysis based on the ITS and nLSU DNA sequence data available in GenBank and published literature was performed to examine the intergeneric relationships of Uromyces. The results obtained revealed that the rust genus is found distributed over 150 countries, territories, and occupancies of the world on around 647 plant genera belonging to 95 plant families. Phylogenetic studies based on LSU and ITS sequence data revealed that Uromyces species are polyphyletic and require more DNA-based analyses for a better understanding of their taxonomic placement.

Fungi are an important and diverse component in various ecosystems. The methods to identify different fungi are an important step in any mycological study. Classical methods of fungal identification, which rely mainly on morphological characteristics and modern use of DNA based molecular techniques, have proven to be very helpful to explore their taxonomic identity. In the present compilation, we provide detailed information on estimates of fungi provided by different mycologistsover time. Along with this, a comprehensive analysis of the importance of classical and molecular methods is also presented. In orderto understand the utility of genus and species specific markers in fungal identification, a polyphasic approach to investigate various fungi is also presented in this paper. An account of the study of various fungi based on culture-based and cultureindependent methods is also provided here to understand the development and significance of both approaches. The available information on classical and modern methods compiled in this study revealed that the DNA based molecular studies are still scant, and more studies are required to achieve the accurate estimation of fungi present on earth.

Severe leaf spot disease was observed on Aloe vera plants in the winters of 2011 and 2012 during a survey of various nurseries of Gwalior, India. Irregular, sunken, dark creamish brown spots having reddish brown margin were noticed on both surfaces of the leaves. The causal organism was consistently isolated from symptomatic leaves on potato dextrose agar media (PDA). A total 59 isolates of fungi were recovered from diseased A. vera leaves, and 37 isolates were identified as belonging to the genus Fusarium. On the basis of morphological characteristics and internal transcribed spacer (ITS) region of rDNA amplified using the primers ITS4/ITS5 the pathogen was identified as Fusarium proliferatum (Matsushima) Nirenberg and pathogenicity of the isolate was confirmed by using Koch’s postulates. To the best of our knowledge, this is the first report of leaf spot disease caused by Fusarium proliferatum on A. vera plants in India.

This paper deals with the study of a leaf spot disease observed on Aloe vera leaves in various nurseries and botanical gardens during the routine surveys of two consecutive years of 2010 and 2011. The symptoms appeared in the form of circular to oval, brown to black, sunken spots on abaxial surface of leaves. The disease was observed only in January to February during the survey. Colonieson PDA were velvety, dark olivaceous to greenish black in colour. The identification of the pathogen was done phenotypically using disease symptoms and microscopic characteristics. Further investigation identified it as Cladosporium sphaerospermum Penzig which was also confirmed at Indian Type Culture Collection (ITCC), IARI, New Delhi, India. According to the literature, this is the first report of Cladosporium sphaerospermum as causal agent of leaf spot disease on A. vera from India.

Pistacia integerrima is a deciduous tree species belonging to the family Anacardiaceae. The plant possesses numerous phytochemicals of ethno-medicinal importance. In a routine mycological survey carried out from July 2013 to June 2014, leaves of P. integerrima were found infected with fungi causing rust and blight diseases. The morphological and microscopic observations revealed three fungi, namely Skierka himalayensis, Pestalotiopsis sp., and Pileolaria pistaciae, which were found to cause rust and blight diseases. One new species of rust fungi, namely Skierka himalayensis sp. nov., and Pestalotiopsis sp. are reported for the first time from India. The detailed descriptions and illustrations of these three phytopathogenic fungi are provided in this paper.