the ACC technique was smaller sized than that of CNF prepared by chemical therapy, suggesting that CNF created by the ACC strategy has larger wettability than CNF produced by other methods. To investigate the prospective application of CNF in agriculture, we examined irrespective of whether coating with CNF protected soybean plants against P. pachyrhizi. We show that a specific CNF property can alter soybean leaf surface hydrophobicity, resulting in decreased formation of pre-infection structures linked with reduced P. pachyrhizi infection.Materials AND Techniques Plant Development Circumstances, Pathogen Inoculation Assay, and CNF TreatmentSusceptible soybean cultivar seeds (Glycine max cv. Enrei) were germinated in a development chamber at 25/20 C with 16-h-light/8-hdark cycle (10050 ol m-2 s-1 ) for three weeks. An isolate from the ASR pathogen P. pachyrhizi T1 (Yamaoka et al., 2014) was maintained on soybean leaves. Fresh urediniospores had been collected and suspended in distilled water with 0.001 Tween 20 (FUJIFILM, Tokyo, Japan). The 3-weekold soybean plants were spray-inoculated with 1 105 spores/ml applying a hand CYP26 Inhibitor review sprayer for uniform spore deposition. The inoculated plants have been maintained within a chamber for 24 h with 905 humidity at 23 C inside the dark. The plants have been then transferred to a development chamber (22/20 C with 16-hlight/8-h-dark cycle) and incubated additional to let symptom development. To quantify ASR lesion quantity on CNF-treated plants, soybean leaves had been spray-inoculated with P. pachyrhizi. At ten days immediately after inoculation, photographs have been taken, and lesions had been counted to calculate the lesion number per cm2 . Lesions have been counted from 54 random fields on three independent leaves. Cellulose nanofiber (marketed as nanoforest ) was supplied through the courtesy of Chuetsu Pulp Paper (Takaoka, Japan). CNF suspension was adjusted to a concentration of 0.1 (v/v) in water like 0.02 Tween 20 just before treatment. Each adaxial and abaxial sides of soybean leaves have been spray-treated with 0.1RFrontiers in Plant Science | frontiersin.orgSeptember 2021 | Volume 12 | ArticleSaito et al.Soybean Rust Protection With CNFCNF till runoff then the treated soybean plants were dried at area temperature for three h just before inoculation. Scopoletin (TCI, Tokyo, Japan) was BRD9 Inhibitor manufacturer pre-solved as 500 mM stock options in dimethyl sulfoxide (DMSO; FUJIFILM) and diluted to 500 in P. pachyrhizi spore suspensions.Quantification of Pre-infection Structures FormationTo quantify the formation of pre-infection structures including germ-tubes and appressoria on control, CNF-, and scopletintreated plants, soybean leaves had been spray-inoculated with P. pachyrhizi 1 105 spores/ml. At 6 h right after inoculation, the leaves were observed with an Olympus BX51 fluorescence microscope right after Calcofluor White (Sigma-Aldrich, St. Louis, MO, Usa) staining and photographed. The germ-tubes forming differentiated appressoria were counted as appressoria. The differentiated germ-tubes without the need of appressoria that grew around the leaf surface have been also counted from at least one hundred urediniosopres on three independent leaves. The formation of pre-infection structures on borosilicate glass slides and polyethylene tape with or without CNF treatment was quantified right after dropping P. pachyrhizi spores (2 105 /ml). Six hours soon after inoculation, pre-infection structures have been observed using a Nikon ECLIPSE 80i phase contrast microscope. The germ-tubes forming differentiated appressoria were counted as appressoria. The differentiated germ-tubes without