Bacterial blight is a significant disease of cotton caused by Xanthomonas citri pv. malvacearum in Pakistan. For effective management, it requires a comprehensive understanding of its pathogenic characteristics. In this study, X. citri pv. malvacearum (Xcm) was isolated from infected samples of cotton collected from the Bahawalpur region. The bacterium was purified and identified through morphological, biochemical, and cultural analyses. Results of the biochemical analysis showed that isolated bacteria showed a positive result in potassium hydroxide (KOH), catalase, oxidative fermentative (OF), urease, starch hydrolysis, citrate utilization, methyl red, Voges-Proskauer, and casein hydrolysis and negative for gram staining, indole production, and arginine dihydrolase test. In cultural analyses X. citri pv. malvacearum appeared mucoid and convex, with colors ranging from yellow to orange on nutrient agar and flattened or slightly raised, ranging from bright to pale yellow with a mucoid texture on yeast extract dextrose calcium carbonate agar (YDCA). This study provides valuable information for researchers and scientists facilitating the accurate identification of Xcm, which is crucial for the In-Vitro assessment of various strategies to determine effective solutions against bacterial blight of cotton.

Conocarpus lancifolius leaves were observed to have typical symptoms of fungal leaf spots in botanical gardens and various nurseries, mainly during the winter and rainy seasons of 2022 and 2023. Leaves of infected plants showed round to irregular grayish-white and dark brownish to black spots with a yellow halo and central whitish color appearance that were variable in size, ranging from 0.5 to 1.5 mm in radius. After processing the samples and purification of the fungus, morphological characteristics such as its color, mycelium pattern, and spore shape were used to identify it as belonging to the genus Alternaria. Following morphological identification pathogenicity test was performed according to Koch’s postulates, proving that the pathogenic fungus Alternaria burnsii was associated with C. lancifolius causing leaf spots. The CTAB method was used to extract DNA to perform molecular characterization and further species-level identification. The fungal DNA was amplified using the ITS and GAPDH genes. Sequencing was done by Macrogen, Korea. A phylogenetic tree was constructed against both genes (ITS and GADPH) by using the sequence of 20 isolates; 19 belong to the Alternaria family and 1 is an outgroup. The suspected isolate with accession no OQ689862, and OQ910482 showed 99.48% and 100% similarity with OP985911 and MN718663, respectively. After submitting sequences to NCBI BanKit, the following accession numbers were assigned against the ITS and GAPDH gene sequences: OQ689862 and OQ910482, respectively. After molecular and morphological characterization, it was determined that Alternaria burnsii was isolated and associated with the leaf spots of the C. lancifolius plant by satisfying Koch’s postulates. According to our research, this is the first report of the leaf spot of C. lancifolius caused by A. burnsii. It is suspected that in the future, C. lancifolius will be infected by other pathogenic microbes. Therefore, to control the disease spread, highly effective management strategies should be adopted.

The fruit and vegetable processing industry generates approximately 30–50% of its input material as waste globally, contributing to environmental degradation and threatening food security. Among these wastes, citrus peels are rich in biologically active compounds with antioxidant and antimicrobial properties. This study aimed to evaluate the potential of Citrus limon peel powder as a natural preservative in cupcakes, offering a sustainable alternative to synthetic additives such as potassium sorbate. Cupcakes were prepared with 1% Citrus limon peel powder and compared with untreated control and 1% potassium sorbate treatments for their physicochemical, microbial, and sensory characteristics. Cakes containing lemon peel powder showed improved shelf life and reduced microbial counts compared to the control, indicating effective antimicrobial activity. In addition, antioxidant analysis confirmed the presence of phenolic compounds contributing to the preservation effect, while sensory evaluation revealed acceptable taste and texture throughout storage. These findings suggest that lemon peel powder can serve as a natural functional ingredient to enhance the shelf stability of baked goods while reducing dependence on synthetic preservatives. This approach not only valorizes agro-industrial waste but also supports healthier food systems and environmental sustainability.

Aloe vera is a perennial, succulent, drought-tolerant plant that grows to a height of 60–100 cm. Its leaves are made up of rind, juice, and gel. During the winter and rainy seasons of 2022 and 2023, typical symptoms of collar rot were observed on A. vera plants in selected botanical gardens and commercial nurseries across Bahawalpur, Punjab, Pakistan. Infected plants exhibited light to dark brown necrotic lesions at the collar region, with lesion diameters ranging from 0.2 to 3.0 cm. Hundred infected leaves from 100 different plants with the same symptoms were collected and processed for isolation. Infected leaves were cut into 4 mm and surface sterilized with 1% NaOCl and rinsed thrice with distilled water. These pieces were placed on potato dextrose agar (PDA) medium and incubated for five days at 25 °C ± 2. The resulting colonies of fungus appeared white in color and spores were crescent in shape. Pathogen that consistently isolated from symptomatic tissues and identified as Fusarium phaseoli based on morphological characteristics and molecular characterization of the internal transcribed spacer (ITS) region and β-tubulin of ribosomal DNA. Pathogenicity was confirmed through controlled inoculation assays, fulfilling Koch’s postulates. To the best of our knowledge, this represents the first report of F. phaseoli causing collar rot on A. vera in Bahawalpur, Punjab, Pakistan.

Spinacia oleracea L. cultivation in South Asia is severely compromised by leaf spot disease caused by fungal plant pathogens, resulting in significant yield and quality losses. In this study, we report the first molecularly confirmed case of an Alternaria burnsii leaf spot on S. oleracea in Pakistan. Symptomatic S. oleracea leaves exhibiting necrotic lesions with concentric rings were collected during a field survey across Bahawalpur district, Punjab, Pakistan in 2024. After isolation, purification and morphological identification it was identified that it belongs to the Alternaria genus. For the confirmation of species, molecular identification was performed; using the ITS and GAPDH primer revealed that the fungal plant pathogen causing leaf spot of S. oleracea is A. burnsii which was also confirmed by phylogenetic analysis. Koch’s postulates were carried out to confirm pathogenicity on detached leaf assays. To assess the virulence of A. burnsii enzymatic analysis was performed. Notably, enzymatic virulence profiling demonstrated a markedly increased production of polygalacturonase (PG: 16.0 ± 0.8 AU), pectin lyase (PNL: 12.0 ± 0.6 AU) and cellulase (CL: 14.0 ± 0.7 AU) relative to controls (all p < 0.001; LSD = 0.16), with PG having the greatest relative increase. This report expands the known host range for A. burnsii and highlights its two-fold threat: as a bioaerosol disseminable by wind and an enzymatic pathogen. These findings highlight the urgent need for integrated disease management strategies for suppressing leaf spot disease in S. oleracea agroecosystems.