Rice blast disease, caused by the fungus Magnaporthe oryzae, poses a significant threat to rice production worldwide. A pot experiment was conducted to test the hypothesis that foliar-applied zinc oxide nanoparticles (ZnONPs) have an inhibitory effect against blast fungus by strengthening the antioxidant defence system in rice plants. Various treatment concentrations of ZnONPs (10, 20, 30, and 40 mg/L) were applied to pathogen-inoculated plants. Foliarly applied ZnONPs lowered the infection efficiency of the sprayed conidia by 73% on the leaf segments compared to the positive control. The lesion number caused by the pathogen in the leaf tissues was significantly reduced compared to the experiment’s positive control, and the sporulation intensity was reduced compared to the positive control. Foliar-applied ZnONPs improved the functions of superoxide dismutase, phenylalanine ammonia-lyase, peroxidase, and catalase enzymes. Furthermore, the growth and yield attributes of rice plants were improved compared to the positive control. Yield and production of rice can be improved with exogenously applied ZnONPs under the rice blast infestation.

A field experiment was conducted in the early and late planting seasons, 2019 to evaluate the effectiveness of grain amaranth (Amaranthus cruentus L.) planted at different timing and proportion as a trap crop for reducing insect pest densities on cucumber. Amaranth was established into cucumber plots two weeks before cucumber (2WBC), same day (SD) with cucumber or two weeks after cucumber (2WAC) in 100:0, 100:25, 100:50, 100:75 and 100:100 cucumber-amaranth proportions. Amaranth planted 2WBC or SD trapped significantly higher numbers of Aulacophora foveicollis and Epilachna chrysomelina compared to 2WAC, corresponding to lower infestations and damage on cucumber, with the highest fruit yield at SD cucumber. While leaf damage was reduced by 68–74% at 100:100, yield increase of 66–69% was obtained at 100:50 relative to sole cucumber plots. Hence, planting grain amaranth SD with cucumber at 100:50 cucumber-amaranth proportion has a great prospect against insect pests of cucumber in a trap–cropping strategy.

The investigation aimed to isolate, identify, characterized and evaluate fungal endophytes from Embelia ribes. The main objective of the study was to identify and evaluate the fungal endophytes for PGP and antifungal activities against selected phytopathogens. A total of eight fungal endophytes were identified by amplifying the ITS region, with phylogenetic analysis confirming their placement within the Ascomycota. Phomopsis and Daldinia sp. dominant species in E. ribes. To evaluate their antifungal activities, three selected endophytes were tested against three fungal pathogens selected based on their relevance and prevalence as plant pathogens in the study area. SEM analysis of the interaction zones between the endophytes and pathogens provided insights into the inhibitory mechanism’s endophytes. Furthermore, the IAA and chitinase activities by endophytes known to exhibit inhibitory activities against pathogenic fungi. Further research is needed to understand the specific mechanisms underlying their inhibitory effects and to assess their performance under field conditions.

Two types of formulations, emulsifiable concentrates (ECs) and nano-emulsions (NEs), were conducted to enhance the activity of the Rheum palmatum L. and Juniperus virginiana L. essential oils (EOs). The efficacy of EOs, ECs, and NEs was evaluated under laboratory and semi-field conditions against Tetranychus urticae Koch eggs and females. In addition, assessing their selectivity towards the predatory mite, Phytoseiulus persimilis Athias-Henriot. The tested ECs and NEs showed toxicity against T. urticae females higher than bulk oils, and all caused 100% un-hatchability of T. urticae eggs. With the exception of EOs and R. palmatum EC, neither the prepared ECs nor NEs showed any phytotoxicity symptoms on treated plants. The residual effects of tested materials were dissipated over time. Juniperus virginiana EO, EC and NE were compatible with P. persimilis. Tested ECs and NEs can aid in more sustainable crop management, to develop low-risk solutions to replace the use of pesticides.

Preliminary survey revealed that 30–40% of Cavendish banana plants were affected with leaf spot disease. Diseased leaf samples were sterilized with 3% sodium hypochlorite solution for 2 min and cultured on PDA media at 25 °C for 15 days followed by microscopic examination. Combined morphological, cultural and microscopic examinations identified two causal agents designated here as BaFI-1 and BaFI-2. Further, BLASTn search using internal transcribed spacer (ITS) rDNA sequences of the isolates also revealed that BaIF-1 and BaFI-2 had 97.13% and 100% homology with Nigrospora sphaerica and Neocordana musae, respectively; which were already reported from Indian and Spanish region. Pathogenecity tests were conducted using 2 months old banana seedlings inoculated with isolated spores in the polyhouse, which addressed Koch’s postulates. To our knowledge, this is the first report confirming Nigrospora sphaerica and Neocordana musae to be the causal agents of leaf spot disease of Cavendish banana in Bangladesh.

Conventional control of sucking pests infesting various vegetables has several drawbacks. Biorational insecticides are increasingly used for pest management due to their limited side effects. A study involving several biorational compounds, viz. spinosad, buprofezin, Beauveria bassiana, Lecanicillium muscarium and a chemical insecticide, fenitrothion was performed by leaf-dip bioassay to measure their efficacy against the bean aphid, A. craccivora Koch. as a representative of sucking pests. Mortality of aphids against treatment with biorational insecticides was recorded in three replicates under laboratory conditions. The lethal concentration (LC50 and LC90) of the treatments were calculated by probit analysis. Efficacy was concentration and time dependent. Spinosad has been found to be more effective than buprofezin. The spinosad (LC50 = 2582.04 ppm) and buprofezin (LC50 = 543.03 ppm) were found to be approximately 88 and 52 times less toxic than fenitrothion. At 48 h post-treatment (HPT), the highest mortality for spinosad and buprofezin was 66.67 and 60.00%, respectively, and reached 93.33% at 72 HPT. Among the two fungal biopesticides, L. muscarium was more effective than B. bassiana. For both, mortality (80–100%) at the higher concentrations was statistically different than others at 144 and 168 HPT. Thus, biorational compounds, particularly spinosad and L. muscarium, are useful for controlling bean aphids.

This work aimed to broaden the spectrum biocontrol activity of Meyerozyma guilliermondii LMA-Cp01. Inhibition of postharvest pathogens, viz., Alternaria alternata, Penicillium italicum, P. digitatum, P. expansum, Botrytis cinerea, and Rhizopus stolonifer was tested on persimmon, oranges, apples, and pears. The effect of spraying or dipping application of the actinomycete for the phytopathogens biocontrol was evaluated. LMA-Cp01 reduced 30 and 50% (R. stolonifer), 53 and 67% (B. cinerea), and 55 and 67% (P. expansum) the disease incidence and severity on apples, respectively. Regarding pears, reductions of 44 and 71% (R. stolonifer) and 65 and 85% (P. expansum) of incidence and severity were respectively achieved. P. italicum and P. digitatum incidence on oranges was reduced by 70 and 72%, respectively, and the severity was also reduced by 85%. The LMA-Cp01 efficacy on apples and oranges was higher by spraying application. LMA-Cp01 is a promising broad-spectrum biocontrol agent against diseases on different hosts.

The Nucleotide-binding site domain (NBD) of plant resistance (R) genes plays a vital role during plant defense signaling. The functional significance of CC-NBS-LRR (Coiled coil-NBS-Leucine Rich Repeat) class of R gene designated ZzR1, characterized from Zingiber zerumbet in earlier studies, was determined by molecular modeling and docking studies. Docked complex showed the ligand GTP interacts with amino acid residues in the cleft made by GLPL and P-loop motifs of the NBD. Heterologous expression of ZzR1 NBS protein was optimized using expression vectors, pEcoli-Nterm-6xHN and pET Directional TOPO and transformed in five Escherichia coli strains namely DH5α, TOP10, BL21DE3, BL21DE3 star and BL21plysS cells. The NBS protein of 36 kDa molecular size was expressed in E. coli BL21DE3 strain using pET TOPO vector. Optimum induction was detected at 30 °C using isopropyl-1-thio-β-D-galactopyranoside (IPTG) (1 mM). The present study provides valuable information on ligand interactions and heterologous expression of ZzR1 NBD protein.

Pyricularia oryzae, the causal agent of rice blast disease, is a serious threat to rice. It reduces the yield and quality of rice. Agrofungicide used to control rice blast is harming the environment and human health. Safer alternative is needed. This study aimed to investigate the antifungal activity of zinc oxide nanoparticles (ZnO NPs) against P. oryzae of Sarawak, and its phytotoxicity towards Sarawak rice. Solvothermal sysnthesis method was used to synthesize two sizes of ZnO NPs (∼20 nm and ∼40 nm). ZnO NPs showed inhibition effect on P. oryzae tested and the effect was isolate dependent. The effect increased along with the concentration increment of ZnO NPs. ZnO NPs were found not affecting the seed germination rate, but on the shoot and root development. The effect varies at different concentration treatments of ZnO NPs. Landrace/genotype dependent phytotoxicity effect of ZnO NPs was observed.

The present study aims to develop eco-friendly Emulsifiable Concentrates (EC) using citronella and lemon grass essential oil (EO) and evaluate its antifungal activity against Phomopsis vexans in Solanum melongena. Among nine prepared formulations, F1 formulation with EO (40%) + vegetable oil (50%) and emulsifier blends (10%) with hydrophilic-lipophilic balance value (12.86) were found suitable for both EO formulations. These formulations (CF1 and LF1) performed well in terms of emulsion stability, cold test, accelerated storage and foam test indicating feasibility for their commercial production. In laboratory studies, at 0.1% concentration, citronella essential oil, lemon grass essential oil and their EC formulations CF1 and LF1 inhibited the growth of P. vexans with EC50 values 0.0087, 0.0098, 0.009 and 0.0126, respectively. Further, under field conditions, CF1 performed better than LF1 formulation in terms of minimum disease severity (32.22%). Hence, EC formulations can be used as natural and eco-friendly fungicide for P. vexans control.