The application of organic fertilizer has been one of the most important agricultural practices to increase tea plant productivity. However, a single organic fertilizer alone could not match the nutrient requirements of tea plant. According to the nutrient demand of tea plant, tea-specific fertilizer with an appropriate nutrient ratio in combination with organic fertilizer would be an appropriate way. A four-year field experiment was conducted to characterize the sensory quality of green tea subjected to four different fertilization treatments, i.e., tea-specific fertilizer (N-P₂O₅-K₂O: 18-8-12) + urea + colza cake, tea-specific fertilizer + urea + livestock waste compost, and tea-specific fertilizer + urea, combined tea-specific fertilizer (referred to as M1, M2, and M3, respectively); nonfertilizing (CK) served as control. The fertilizer formulated specifically for tea could enhance the taste qualities of green tea, such as water extract, caffeine, tea polyphenol, EGCG, and ECG. However, the effect of this fertilizer on enhancing the aroma level of green tea was weaker than that of the application of tea-specific fertilizer combined with organic fertilizer, whereby this combined fertilization significantly improved the concentration of green tea aroma compounds, such as D-limonene, cis-jasmone, nonanal, linalool, cis-3-hexenyl hexanoate, and cis-3-hexenyl benzoate. This study provides a theoretical basis for judicious fertilization by combining tea-specific fertilizer and organic fertilizer in tea orchards.

Gray blight disease stands as one of the most destructive ailments affecting tea plants, causing significant damage and productivity losses. However, the dynamic roles of defense genes during the infection of gray blight disease remain largely unclear, particularly concerning their distinct responses in resistant and susceptible cultivars. In the pursuit of understanding the molecular interactions associated with gray blight disease in tea plants, a transcriptome analysis unveiled that 10,524, 17,863, and 15,178 genes exhibited differential expression in the resistant tea cultivar (Yingshuang), while 14,891, 14,733, and 12,184 genes showed differential expression in the susceptible tea cultivar (Longjing 43) at 8, 24, and 72 h post-inoculation (hpi), respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses highlighted that the most up-regulated genes were mainly involved in secondary metabolism, photosynthesis, oxidative phosphorylation, and ribosome pathways. Furthermore, plant hormone signal transduction and flavonoid biosynthesis were specifically expressed in resistant and susceptible tea cultivars, respectively. These findings provide a more comprehensive understanding of the molecular mechanisms underlying tea plant immunity against gray blight disease.

From the 1950s to the 1970s, approximately 80,000 kg of tea seeds were introduced from mainland China to the Xizang Autonomous Region for experimental cultivation. To assess the genetic diversity patterns of these tea accessions following more than half a century of acclimatization to plateau environments, we analyzed genetic variation, population structure, and genetic distinctiveness among fifty tea germplasm using nine phenotypic traits and 30 SSR markers. Phenotypic analysis revealed a moderately high level of genetic diversity, as indicated by the mean Shannon diversity index (H′ = 1.29). Principal component analysis (PCA) indicated that phenotypic variation was not geographically structured across the collection sites. The SSR markers exhibited a high degree of polymorphism, with an average polymorphic information content (PIC) of 0.610 and a genetic diversity index (I) of 1.437, indicating substantial genetic variation. Analysis of molecular variance (AMOVA) revealed that genetic differentiation occurred predominantly within populations, accounting for 91.49% of the total genetic variation. Similarly, 97.86% of the variation was attributed to differences within elevational gradients. Discriminant analysis of principal components (DAPC) and Bayesian population structure modeling (STRUCTURE) both identified two genetic clusters among the studied genotypes. Our results have practical implications for tea breeding programs by providing guidance for parental selection, informing germplasm collection management, and supporting the conservation of genetic resources.

The tea plant (Camellia sinensis (L.) O. Kuntze) is a globally important crop, yet its cultivation is continually challenged by a range of viral pathogens that can compromise plant health and product quality. In this study, eighteen symptomatic leaves were collected from the Hubei Province Tea Germplasm Resources Nursery, China, representing multiple cultivars and diverse genetic backgrounds. The samples were pooled into three groups and subjected to ribodepleted transcriptome sequencing. Analyses revealed a complex virome, with Tea plant necrotic ring blotch virus (TPNRBV) dominating Pools A and B, whereas Badnavirus betacolocalasiae was the most prevalent in Pool C. Functional enrichment of viral genes indicated involvement in multiple biological processes, including replication, host interaction, and metabolism. Notably, two previously uncharacterized viruses were identified: Tea plant-associated ourmia-like virus 1 (TeaOLV1) and Tea plant-associated rhabdo-like virus 1 (TeaRLV1). Phylogenetic reconstruction positioned TeaOLV1 within the Penoulivirus genus, while TeaRLV1 formed a distinct clade among plant-associated rhabdoviruses. Conserved motif analysis revealed typical viral domains, accompanied by lineage-specific variations in tea plants. Collectively, these findings enhance our understanding of the viral diversity in tea plants, provide refined taxonomic placement for newly identified viruses, and offer molecular insights into their evolutionary relationships and potential functional roles.

The tea leaf beetle Basilepta melanopus is a devastating leaf-feeding pest of tea plants, with its infestation area and damage severity in Chinese tea plantations continuously increasing. Characterizing the morphology and distribution of sensilla provides a morphological basis for understanding the behavioral mechanisms underlying host recognition, mate localization, and environmental perception of this pest. In this study, the morphology, ultrastructural characteristics, distribution and sexual dimorphism of sensilla on antennae, mouthparts, legs, and external genitalia of B. melanopus adults were examined by stereomicroscopy and scanning electron microscopy (SEM). Nine types and thirty-nine subtypes of sensilla were observed. These include various types on the antennae, including Böhm bristles, sensilla chaetica, sensilla trichodea, sensilla basiconica, sensilla auricillica, sensilla coeloconica, and sensillar pits, and many subtypes. The two types of sensilla unique to the mouthparts are sensilla styloconica and sensilla campaniformia. Sensilla chaetica and sensilla trichodea are also found on the tarsi. In addition, sensilla trichodea and sensilla basiconica were identified on the external genitalia of the female insect. On the male external genitalia, four types of sensilla were observed: sensilla trichodea, sensilla chaetica, sensilla basiconica, and sensilla coeloconica. There were also differences in the number and size of sensilla between males and females. This study investigated the relationship between the sensilla of B. melanopus and its key behavioral activities, namely feeding and oviposition, through detailed morphological observations and systematic analysis of these sensory structures. The findings provide a conceptual framework and offer novel perspectives for future research on the behavioral ecology and integrated management of this species.