Agave plants are important crassulacean acid metabolism (CAM) plants with multiple agricultural uses, such as being used in tequila and fiber production. Agave hybrid H11648 ((A. amaniensis Trel. and Nowell × A. angustifolia Haw.) × A. amaniensis) is the main cultivated Agave species for fiber production in large tropical areas around the world. In this study, we conducted a transcriptome analysis of A. H11648. About 49.25 million clean reads were obtained by Illumina paired-end sequencing. De novo assembly produced 148,046 unigenes with more than 40% annotated in public databases, or matched homologs in model plants. More homologous gene pairs were found in Asparagus genome than in Arabidopsis or rice, which indicated a close evolutionary relationship between Asparagus and A. H11648. CAM-related gene families were also characterized as previously reported in A. americana. We further identified 12 cellulose synthase genes (CesA) in Asparagus genome and 38 CesA sequences from A. H11648, A. americana, A. deserti and A. tequilana. The full-length CesA genes were used as references for the cloning and assembly of their homologs in other Agave species. As a result, we obtained CesA1/3/4/5/7 genes with full-length coding region in the four Agave species. Phylogenetic and expression analysis revealed a conserved evolutionary pattern, which could not explain the distinct fiber traits in different Agave species. We inferred that transcriptional regulation might be responsible for Agave fiber development. This study represents the transcriptome of A. H11648, which would expand the number of Agave genes and benefit relevant studies of Agave fiber development.

Coffee is a significant traded commodity for developing countries. Among the various diseases affecting coffee, anthracnose caused by Colletotrichum spp. has re-emerged as a major constraint on global coffee production. To better understand the Colletotrichum species complex associated with coffee anthracnose, we characterized Colletotrichum spp. using a combination of phenotypic traits, MAT1-2 (ApMat) gene analysis, multi-locus phylogenetic (ITS, ACT, CHS-1, and GAPDH), and pathogenicity assays. A total of 74 Colletotrichum isolates were collected from coffee plants exhibiting anthracnose symptoms across nine coffee plantations in China. Among these, 55 isolates were identified as the C. gloeosporioides species complex using the ApMat locus, while the remaining 19 isolates were identified through multi-locus phylogenetic analyses. The isolates represented seven Colletotrichum species from five species complexes: C. gloeosporioides (including C. siamense, C. nupharicola, and C. theobromicola), C. boninens (C. karstii), C. gigasporum (C. gigasporum), C. orchidearum (C. cliviicola), and C. magnum (C. brevisporum). This is the first report of C. nupharicola and C. cliviicola causing coffee anthracnose worldwide, and the first report of C. nupharicola in China. Pathogenicity tests confirmed that all seven species were capable of infecting coffee leaves. This research enhances our understanding of the Colletotrichum species responsible for coffee anthracnose, and provides valuable insights for developing effective disease management strategies.

Phytophthora-induced crop diseases, commonly known as “plant plagues”, pose a significant threat to global food security. In this study, strain ASG80 was isolated from sisal roots and demonstrated a broad-spectrum antagonistic activity against several Phytophthora species and fungal pathogens. Strain ASG80 was identified as Streptomyces luteireticuli via phylogenetic analysis, digital DNA–DNA hybridization (dDDH), and average nucleotide identity (ANI). Whole-genome sequencing identified 40 biosynthetic gene clusters (BGCs) related to secondary metabolite production, including antimicrobial compounds. Strain ASG80 extract exhibited broad-spectrum inhibitory activity against Phytophthora nicotianae, P. vignae, P. cinnamomi, and P. sojae. Pot experiments showed that strain ASG80 extract significantly reduced sisal zebra disease incidence, with an efficacy comparable to the fungicide metalaxyl. These findings suggest that strain ASG80 is a promising biocontrol agent with substantial potential for managing Phytophthora-related diseases in agriculture.

Coffee (Coffea arabica L.) is a very important crop in China and in the global economy. During March 2019, symptoms of leaf blight were observed on coffee planted at Hainan and Yunnan Provinces in ...

Brown rot disease caused by Pyrrhoderma noxium is a widespread disease that severely affects the roots of rubber trees (Hevea brasiliensis Muell. Arg.). The economic losses, along with environmental and health problems arising from the use of disease control chemicals, have raised the interest of scholars to explore the use of biological control agents for the effective control of fungal pathogen P. noxium. Here, the inhibition effect of the culture filtrate of B. subtilis Czk1 on P. noxium was demonstrated. The findings indicate that the antifungal activity of this strain is mediated wholly or partly by compounds produced in the culture filtrate. The combined use of liquid chromatography–tandem mass spectrometry and antifungal activity assays rapidly identified compounds produced by B. subtilis Czk1. Metabolic profiles were assessed and used to identify major metabolites based on the scores of variable importance in the projection and the plot scores of principal component analysis. A total of 296 differential metabolites were screened, including 208 in positive ion mode and 88 in negative ion mode. Two key metabolites, diacetyl and trans-2-octenoic acid, were screened from 29 metabolites by antifungal activity assays. The median effective concentration (EC₅₀) of trans-2-octenoic acid and diacetyl were 0.9075 mg/mL and 4.8213 mg/mL, respectively. The antifungal metabolites can disrupt the internal structure of the pathogenic fungal mycelium, thereby impeding its growth. This study is expected to contribute to the existing knowledge of Czk1-produced metabolites and their future antifungal applications. This study is also expected to provide a new biopreservative perspective on unexplored antifungal metabolites produced by Czk1 as a biocontrol agent.

Agave species are widely cultivated crassulacean acid metabolism (CAM) plants for alcoholic beverages, food and fiber production. Among these, the Agave hybrid H11648 ((A. amaniensis × A. angustifolia) × A. amaniensis) is the main cultivar for sisal fiber in the tropical areas of Brazil, China, and African countries. The plants of Agave hybrid H11648 have a long life cycle and large leaves, which require a huge amount of nitrogen nutrient. However, the molecular basis of nitrogen transport and allocation has not been well understood in agave. In this study, we identified 19 NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER FAMILY(NPF) genes (called AhNPFs) with full-length coding sequences in Agave hybrid H11648. Our analysis of gene expression in various types of tissues revealed the tissue-specific expression pattern of AhNPFs. We further examined their expression patterns at different leaf developmental stages, under abiotic/biotic stresses and nutrient deficiency. The results reveal several candidate regulators in the agave NPF family, including AhNPF4.3/5.2/7.1. We first characterized the NPF genes in agave based on published leaf transcriptome datasets and emphasized their potential functions. The study will benefit future studies related to nitrogen nutrient in agave.