WRKY transcription factors regulate diverse biological processes in plants, including abiotic and biotic stress responses, and constitute one of the largest transcription factor families in higher plants. Although the past decade has seen significant progress towards identifying and functionally characterizing WRKY genes in diverse species, little is known about the WRKY family in sorghum ( Sorghum bicolor (L.) moench). Here we report the comprehensive identification of 94 putative WRKY transcription factors ( Sb WRKYs). The Sb WRKYs were divided into three groups (I, II, and III), with those in group II further classified into five subgroups (IIa–IIe), based on their conserved domains and zinc finger motif types. WRKYs from the model plant Arabidopsis ( Arabidopsis thaliana ) were used for the phylogenetic analysis of all SbWRKY genes. Motif analysis showed that all Sb WRKYs contained either one or two WRKY domains and that Sb WRKYs within the same group had similar motif compositions. SbWRKY genes were located on all 10 sorghum chromosomes, and some gene clusters and two tandem duplications were detected. SbWRKY gene structure analysis showed that they contained 0–7 introns, with most SbWRKY genes consisting of two introns and three exons. Gene ontology (GO) annotation functionally categorized SbWRKYs under cellular components, molecular functions and biological processes. A cis -element analysis showed that all SbWRKYs contain at least one stress response-related cis -element. We exploited publicly available microarray datasets to analyze the expression profiles of 78 SbWRKY genes at different growth stages and in different tissues. The induction of SbWRKYs by different abiotic stresses hinted at their potential involvement in stress responses. qRT-PCR analysis revealed different expression patterns for SbWRKYs during drought stress. Functionally characterized WRKY genes in Arabidopsis and other species will provide clues for the functional characterization of putative orthologs in sorghum. Thus, the present study delivers a solid foundation for future functional studies of SbWRKY genes and their roles in the response to critical stresses such as drought.

Members of the plant-specific B3-domain transcription factor family have important and varied functions, especially with respect to vegetative and reproductive growth. Although B3 genes have been studied in many other plants, there is limited information on the genomic organization and expression of B3 genes in grapevine (Vitis vinifera L.). In this study, we identified 50 B3 genes in the grapevine genome and analyzed these genes in terms of chromosomal location and syntenic relationships, intron–exon organization, and promoter cis-element content. We also analyzed the presumed proteins in terms of domain structure and phylogenetic relationships. Based on the results, we classified these genes into five subfamilies. The syntenic relationships suggest that approximately half of the genes resulted from genome duplication, contributing to the expansion of the B3 family in grapevine. The analysis of cis-element composition suggested that most of these genes may function in response to hormones, light, and stress. We also analyzed expression of members of the B3 family in various structures of grapevine plants, including the seed during seed development. Many B3 genes were expressed preferentially in one or more structures of the developed plant, suggesting specific roles in growth and development. Furthermore, several of the genes were expressed differentially in early developing seeds from representative seeded and seedless cultivars, suggesting a role in seed development or abortion. The results of this study provide a foundation for functional analysis of B3 genes and new resources for future molecular breeding of grapevine.

The genus Agaricus is known for its medicinal and edible species but also includes toxic species that belong to section Xanthodermatei. Previous phylogenetic reconstruction for temperate species, based on sequence data of nuc rRNA gene (rDNA) internal transcribed spacers (ITS), has revealed two major groups in this section and a possible third lineage for A. pseudopratensis. Recent research in Agaricus has shown that classifications need improving with the addition of tropical taxa. In this study we add new tropical collections to section Xanthodermatei. We describe three species from collections made in Pakistan and Thailand and include them in a larger analysis using all available ITS data for section Xanthodermatei. Agaricus bisporiticus sp. nov. and A. fuscopunctatus sp. nov. are introduced based on molecular and morphological studies, whereas A. microvolvatulus is recorded for the first time in Asia. Specimens from Thailand however have a much larger pileus than the type specimens from Congo. In maximum likelihood (ML) and maximum parsimony (MP) phylogenetic analyses these three species cluster with A. pseudopratensis from the Mediterranean area and A. murinocephalus recently described from Thailand. In Agaricus section Xanthodermatei this new group is monophyletic and receives low bootstrap support whereas the two previously known groups receive strong support. Within the new group, the most closely related species share some traits, but we did not find any unifying morphological character; however the five species of the group share a unique short nucleotide sequence. Two putatively toxic species of section Xanthodermatei are now recognized in Pakistan and six in Thailand.

The necrotrophic fungus Botrytis cinerea causes devastating pre- and post-harvest yield losses in grapevine (Vitis vinifera L.). Although B. cinerea has been well-studied in different plant species, there is limited information related to the resistance and susceptibility mechanisms of Vitis genotypes against B. cinerea infection. In the present study, leaves and berries of twenty four grape genotypes were evaluated against B. cinerea infection. According to the results, one genotype (Ju mei gui) was highly resistant (HR), one genotype (Kyoho) was resistant (R), eight genotypes were susceptible (S), and fourteen genotypes were highly susceptible (HS) against infection of B. cinerea in leaves. Whereas in the case of B. cinerea infection in grape berry, three genotypes were found to be highly resistant, three resistant, eleven genotypes susceptible, and seven were highly susceptible. To further explore the mechanism of disease resistance in grapevine, we evaluated “Ju mei gui” and “Summer black” in terms of B. cinerea progression, reactive oxygen species reactions, jasmonic acid contents, and the activities of antioxidant enzymes in leaf and fruit. We surmise that the resistance of “Ju mei gui” is due to seized fungal growth, minor reactive oxygen species (ROS) production, elevated antioxidant enzyme activity, and more jasmonic acid (JA) contents. This study provides insights into the resistance and susceptibility mechanism of Vitis genotypes against B. cinerea. This will help for the selection of appropriate germplasm to explore the molecular basis of disease resistance mechanisms in grapevine.

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A new club fungus, Clavariadelphus pakistanicus sp. nov. included within genus Clavariadelphus Donk and section Clavariadelphus, is described from the Himalayan moist temperate forests of Pakistan. Clavariadelphus pakistanicus is characterized by its solitary growth habit, clavate to subcylindrical gray–orange to orange–white longitudinally rugose to rugulose basidiocarps with broadly ellipsoid smooth basidiospores measuring 7.5–9.2 μm × 4.0–5.6 μm, and a dense white rhizomorphic mat. Molecular phylogenetic analyses using internal transcribed spacer (ITS) rDNA cluster C. pakistanicus, Clavariadelphus sachalinensis (S. Imai) Corner, and Clavariadelphus truncatus (Quél.) Donk as sister clades.

Botrytis cinerea is a necrotrophic fungal phytopathogen with devastating effects on many Vitis genotypes. Here, a screening of 81 Vitis genotypes for leaf resistance to B. cinerea revealed two highly resistant (HR), twelve resistant (R), twenty-five susceptible (S) and forty-two highly susceptible (HS) genotypes. We focused on the HR genotype, ‘Zi Qiu’ (Vitis davidii), and the HS genotype ‘Riesling’ (V. vinifera), to elucidate mechanisms of host resistance and susceptibility against B. cinerea, using detached leaf assays. These involved a comparison of fungal growth, reactive oxygen species (ROS) responses, jasmonic acid (JA) levels, and changes in the anti-oxidative system between the two genotypes after inoculation with B. cinerea. Our results indicated that the high-level resistance of ‘Zi Qiu’ can be attributed to insignificant fungal development, low ROS production, timely elevation of anti-oxidative functions, and high JA levels. Moreover, severe fungal infection of ‘Riesling’ and sustained ROS production coincided with relatively unchanged anti-oxidative activity, as well as low JA levels. This study provides insights into B. cinerea infection in grape, which can be valuable for breeders by providing information for selecting suitable germplasm with enhanced disease resistance.

A new thelephoroid species, Thelephora iqbalii, collected from the Himalayan moist temperate (HMT) forests of Pakistan, is characterized by small coralloid basidiomata bearing long, narrow ridges with fine hairs on their branches and hymenia that are cyanescent in KOH. An ITS-based phylogeny comparing T. iqbalii with other Thelephora species is also presented.