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Effect of leaf aqueous extracts of Khaya senegalensis were determined on disease causing fungi. This work aimed to determine the antifungal effect of Khaya senegalensis leaf extract on the growth of some selected fungi. In this study, the phytopathogenic fungi isolated from the spoiled bread are identified based on morphological and cultural characters. The identification of the fungi was confirmed by pathogenicity tests, the organisms were found to be Mucor spp. and Rhizopus spp. Leaf aqueous extracts of different concentrations (100, 200, 300, 400 and 500 mg mL-1) of Khaya senegalensis were added to the growth media prior to inoculation. The aqueous extracts have inhibited the mycelial growth of the fungi, and this effect gradually increased with an increase in the concentration. It could be emphatically concluded that the tested plant extract can effectively control fungi affecting. This makes it potential biofungicide for the management of fungi associated with bread as it is cheap and environmentally safe due to their fungicidal and fungitoxic ability.

Rhizoctonia is a widespread soilborne fungus in different agroecosystems worldwide. It has been reported as a destructive fungal pathogen that caused various types of diseases on a wide variety of crops. The aim of this study was to characterize Rhizoctonia spp. isolated from various crops. We obtained 37 Rhizoctonia isolates from rice, corn, spinach, chrysanthemum, and chili grown in various locations in Peninsular Malaysia. A total of 35 isolates were classified under Rhizoctonia solani (multinucleate) and two isolates belonged to binucleate Rhizoctonia (BNR) according to the number of nuclei and morphological characteristics. Based on rDNA-ITS sequences and PCR profiling using AG group-specific primers, these isolates were identified as R. solani AG-1 IA (75.6%), AG-1 ID (10.8%), AG-2-2 IV (2.7%), AG-4 HG-I (5.4%), BNR AG-Fa (2.7%), and AG-A (2.7%). A specific primer of binucleate Rhizoctonia AG-Fa was designed and its specificity was evaluated by PCR. Further investigation using tef-1α gene confirmed the AG group identities for these isolates. Clustering analysis of molecular markers (OPA13 and OPE-6, 2080 iPBS, and 2249 iPBS and ISSR 3) supported the AG concept rather than geographical origin or plant host. Pathogenicity tests on the leaves of rice and corn showed that R. solani AG-1 IA rice isolates cause necrotic lesions greater than AG-1 IA corn isolates. Rhizoctonia solani AG-1 IA, AG-2-2IV, and AG-4 HG-I isolates cause necrotic lesions greater than BNR isolates on seedling of cabbage, cauliflower, and radish. To the best of our knowledge, this is the first study on morphology and molecular characterization of Rhizoctonia spp. isolated from various crops and regions in Malaysia.

Objective: The present study was carried out to determine the antifungal activity of Mangifera indica leaves extract on fungi isolated from bread vended within Bakori. Methods: The powdered form of M. indica leaves was used to prepare the extract using ethanol, the leaves were air dried at room temperature for 10 days. Results: The chemical test was carried out to identify the secondary metabolites, some of the metabolites that were present include alkaloids, saponins, flavonoids, steroids, and tannins. Both fungal isolates were identified on the basis of morphological characteristics as Aspergillus niger, Aspergillus flavus, and Mucor spp. The antifungal activity of M. indica leaves extract was determined using agar well diffusion method on Aspergillus and Mucor spp. The results showed that the extract was found to inhibit A. niger at 100 mg/ml, 50 mg/ml, and 25 mg/ml with 13.9 mm, 11.5 mm, and 8.0 mm, respectively, and A. flavus at 100 mg/ml, 50 mg/ml, and 25 mg/ml with 13.6 mm, 11.2 mm, and 8.1 mm, respectively, while Mucor spp. was found to be resistant at 25 mg/ml while 100 mg/ml and 50 mg/ml showed an activity. Minimum inhibitory concentration result showed a promising activity against Aspergillus spp. at 25 mg/ml while Mucor spp. at 50 mg/ml. Conclusion: Therefore, M. indica leaf extracts can be used in the treatment of diseases or illness caused by Aspergillus and Mucor spp.

Field trials were conducted during the 2018 rainy season at the Federal University Dutsin-Ma Teaching and Research Farm, Badole. The aim of the work was to evaluate the influence of different levels of NPK fertilizer (0, 40, 80 kg ha-1) and poultry manure (0, 4, 8 tons’ ha-1) on the growth of okra. The trial was laid out in a Randomized Complete Block Design (RCBD) and replicated three times. The application of 4 and 8 tons’ ha-1 of poultry manure showed significant difference on the number of plant per plot at 4 and 6WAS. While the application of NKP 15:15:15 at all level were statistically at par on the number of plant per plot. The application of poultry manure and NPK 15:15:15 showed significant difference among the treatment to plant height, number of leaves, leaves area, stem girth at various weeks of data collection. The increase in the level of poultry manure and NPK 15:15:15 fertilizer showed the significant effects on number plant, number of leave per plant, leave area, plant height, stem girth. And some of parameters were statistically at far by varied level of factors and time. Okra variety Clemson spineless significantly gave taller plants and increase in the plant organs. Both NPK fertilizer and poultry manure were found to play a significant role in increasing the growth of okra plant.

Heat stress or global warming is a continuous temperature fluctuation that affects the environment and damage plant tissues because of the hormonal imbalances in plants. Yield losses resulting from heat stress are a major threat to global food security. Plant growth-promoting bacteria (PGPB) may be utilized to lessen this loss in yield. PGPB containing aminocyclopropane-1-carboxylic acid (ACC) deaminase activity can enhance plant growth that various abiotic stresses inhibit. This work was conducted to evaluate the effect of ACC deaminase and exopolysaccharides producing bacteria on maize plants grown under heat stress. The stressed plants were kept at 45 °C, while non-stressed plants were grown at a temperature of 28 - 35 °C. In 45 days of the growing period under heat stress, the plant growth and activities were decreased, however, in the presence of PGPB (isolated from soil and plant tissues in Muzaffagarh, Pakistan) containing ACC deaminase activity, the plant activities and biomass were increased compared to their respective control. The ACC deaminase-producing bacteria played a significant role by enhancing the physiological activities of the plants like chlorophyll a and b, carotenoid pigments, and proline content. Enzymatic activities like superoxide dismutase (81 %), peroxidase (57.8 %), and catalase (50.27 %) were increased. The relative water content of the maize plants was increased in Treatment one (T1) with 300, and 200 % for non-heat and heat, respectively, while the control was having 220, and 200 % for non-heat and heat, respectively. Soluble sugar content was improved with T1 having the highest values (4,000 and 5,700 g/mol) for heat and non-heat, respectively. The control was having 900, and 2300 g/mol for heat and non-heat, respectively. The application of ACC deaminase-producing bacteria on maize can help to overcome the adverse effects of heat stress and help the plant to survive under stress condition. HIGHLIGHTS Heat stress is a continuous temperature fluctuation that affects the environment and damage plant tissues because of the hormonal imbalances in plants, and yield losses resulting from heat stress are a major threat to global food security This research work was carried out to assess the effect of ACC deaminase and exopolysaccharides producing bacteria on maize plants grown under heat stress The use of ACC deaminase-producing bacteria on maize can help to overcome the adverse effects of heat stress and help the plant to survive under stress condition GRAPHICAL ABSTRACT

The bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most serious rice diseases, causing huge yield losses worldwide. Several technologies and approaches have been opted to reduce the damage, however, these have had limited success. Recently, scientists have been focusing their efforts on developing efficient and environmentally friendly nanobactericides for controlling bacterial diseases in rice fields. In the present study, a scanning electron microscope (SEM), transmission electron microscope (TEM), and a confocal laser scanning microscope (CLSM) were utilized to investigate the mode of actions of ginger EOs on the cell structure of Xoo. The ginger EOs caused the cells to grow abnormally, resulting in an irregular form with hollow layers, whereas the dimethylsulfoxide (DMSO) treatment showed a typical rod shape for the Xoo cell. Ginger EOs restricted the growth and production of biofilms by reducing the number of biofilms generated as indicated by CLSM. Due to the instability, poor solubility, and durability of ginger EOs, a nanoemulsions approach was used, and a glasshouse trial was performed to assess their efficacy on BLB disease control. The in vitro antibacterial activity of the developed nanobactericides was promising at different concentration (50–125 µL/mL) tested. The efficacy was concentration-dependent. There was significant antibacterial activity recorded at higher concentrations. A glasshouse trial revealed that developed nanobactericides managed to suppress BLB disease severity effectively. Treatment at a concentration of 125 μL/mL was the best based on the suppression of disease severity index, AUDPC value, disease reduction (DR), and protection index (PI). Furthermore, findings on plant growth, physiological features, and yield parameters were significantly enhanced compared to the positive control treatment. In conclusion, the results indicated that ginger essential oils loaded-nanoemulsions are a promising alternative to synthetic antibiotics in suppressing Xoo growth, regulating the BLB disease, and enhancing rice yield under a glasshouse trial.

Fusarium wilt disease incited by Fusarium oxysporum f. sp. niveum (FON) is the utmost devastating soil-inhabiting fungal pathogen limiting watermelon (Citrullus lanatus) production in Malaysia and globally. The field disease survey of fusarium wilt was carried out during December 2019 and November 2020, in three major production areas (3 farmer fields per location) in Peninsular Malaysia namely, Mersing, Serdang and Kuantan and disease incidence of 30 and 45%, was recorded for each year, respectively. Infected watermelon plants showed symptoms such as vascular discoloration, brown necrotic lesions to the soil line or the crown, one-sided wilt of a plant, or a runner or the whole plant. Infected root and stem tissues, 1-2 cm pieces were surface sterilized with 0.6% NaOCl for 1 minute followed by double washing with sterile water. The disinfected tissues were air-dried and transferred onto semi-selective Komada's medium (Komada 1975) and incubated for 5 days. The fungal colonies produced were placed on potato dextrose agar (PDA) to attain a pure culture and incubated at 25±2℃ for 15 days. The pure fungal colony was flat, round and light purple in color. Macroconidia were straight to slightly curved, 18.56-42.22 µm in length, 2.69-4.08 µm width, predominantly 3 septate and formed in sporodochia. Microconidia measured 6.16-10.86 µm in length and 2.49-3.83 µm in width, kidney-shaped, aseptate and were formed on short monophialides in false-heads. Chlamydospores were single or in pairs with smooth or rough walls, found both terminally or intercalary. To confirm their pathogenicity, two-week-old watermelon seedlings (cv. NEW BEAUTY) were dipped into spore suspension (1 ˟ 106 spores/ml) of representative isolates of JO20 (Mersing), UPM4 (Serdang) and KU41 (Kuantan) for 30 second and then moved into 10 cm diameter plastic pots containing 300 g sterilized soil mix. Disease symptoms were assessed weekly for one month. Control seedlings were immersed in sterile distilled water before transplanting. The inoculated seedlings showed typical Fusarium wilt symptoms like yellowing, stunted growth, and wilting, which is similar to the farmer field infected plants. However, the seedlings inoculated by sterile distilled water remained asymptomatic. The pathogen was successfully re-isolated from the infected seedlings onto Komada's medium, fulfilling the Koch's postulate. For the PCR amplification, primers EF-1 and EF-2 were used to amplify the tef1-α region. A Blastn analysis of the tef1-α sequences of the isolates JO20 (accession nos. MW315902), UPM4 (MW839560) and KU41 (MW839562) showed 100% similarity; with e-value of zero, to the reference sequences of F. oxysporum isolate FJAT-31690 (MN507110) and F. oxysporum f. sp. niveum isolate FON2 790-2 (MN057702). In Fusarium MLST database, isolates JO20, UPM4 and KU41 revealed 100% identity with the reference isolate of NRRL 22518 (accession no. FJ985265). Though isolate FJ985265 belongs to the f. sp. melonis, earlier findings had revealed Fusarium oxysporum f. sp. are naturally polyphyletic and making clusters with diverse groups of the Fusarium oxysporum species complex (O'Donnell et al. 2015). The isolates JO20, UPM4 and KU41 were identified as F. oxysporum f. sp. niveum based on the aligned sequences of tef1-α and molecular phylogenetic exploration by the maximum likelihood method. To the best of our knowledge, this is the first report of F. oxysporum f. sp. niveum as a causative pathogen of Fusarium wilt disease of watermelon in Malaysia. Malaysia enables to export watermelon all-year-round in different countries like Singapore, Hong-Kong, The United Arab Emirates (UAE), and Netherlands. The outburst of this destructive soil-borne fungal pathogen could cause hindrance to watermelon cultivation in Malaysia. Thus, growers need to choice multiple management tactics such as resistant varieties, cultural practices (soil amendments and solarization), grafting, cover crops and fungicide application to control this new pathogen.

Colletotrichum falcatum Went causes red rot disease in sugarcane farming in the tropical and sub-tropical regions. This disease causes significant economic loss to the sugarcane production industry. Successful disease management strategies depend on understanding the evolutionary relationship between pathogens, genetic diversity, and population structure, particularly at the intra-specific level. Forty-one isolates of C. falcatum were collected from different sugarcane farms across Bangladesh for molecular identification, phylogeny and genetic diversity study. The four genes namely, ITS-rDNA, β-tubulin, Actin and GAPDH sequences were conducted. All the 41 C. falcatum isolates showed a 99–100% similarity index to the conserved gene sequences in the GenBank database. The phylogram of the four genes revealed that C. falcatum isolates of Bangladesh clustered in the same clade and no distinct geographical structuring were evident within the clade. The four gene sequences revealed that C. falcatum isolates from Bangladesh differed from other countries´ isolates because of nucleotides substitution at different loci. The genetic structure of C. falcatum isolates were determined using ISSR marker generated 404 polymorphic loci from 10 selected markers. The percentage of polymorphic loci was 99.01. The genetic variability at species level was slightly higher than at population level. Total mean gene diversity at the species level was 0.1732 whereas at population level it was 0.1521. The cluster analysis divided 41 isolates into four main genetic groups and the principal component analysis was consistent with cluster analysis. To the best of our knowledge, this is the first finding on characterizing C. falcatum isolates infesting sugarcane in Bangladesh. The results of this present study provide important baseline information vis a vis C. falcatum phylogeny analysis and genetic diversity study.

Fusarium oxysporum f. sp. niveum (Fon) is the causative agent of Fusarium wilt disease of watermelon; it is the most serious soil-borne pathogen around the globe. The yield loss is around 30–80% or even more, and is presently a major hindrance to watermelon cultivation worldwide. Initially, the infected watermelon plant shows symptoms like loss of turgor pressure of the leaves and vines that can be recovered at night. The progress of the disease in contaminated transplants turns into dull green to yellow and finally necrotic. When the fungus continues to colonize the xylem vessel, it usually forms more tyloses, finally limiting water movement and causing wilt. The correct identification of the pathogen is necessary for proper disease control. As such, the selection of a molecular marker could serve as an effective means of screening the pathogen. Additionally, different methods have also been reported for the identification of Fon. Therefore, this review focused on the comprehensive description of the biology, diversity, detection, aggressiveness, mycotoxin production, and eco-friendly management strategies of the Fusarium wilt disease of watermelon.