During 2019, fruit blight and rot symptoms were observed on olive (O. europaea L.) fruits on trees grown in the Experimental Farm, Faculty of Agriculture, Sohag University, Egypt. Fungal isolates recovered from symptomatic fruits were identified as Curvularia lunata (Walker) Boedijn (two isolates) and A. alternata (Fr.) Keissl. (one isolate). Koch’s postulates were fulfilled by a pathogenicity test conducted in vitro on olive fruits wounded before inoculation with fungal isolates and incubation at 25 ± 0.2 °C in a moist chamber for a week. During incubation, we observed the development of blight and rot symptoms on fruits inoculated with both isolates of C. lunata, similar to the natural symptoms described. Conversely, A. alternata was nonpathogenic to olive fruits. PCR amplification using the specific P1 and P2 primers to C. lunata based on the Clg2p Ras protein gene sequences resulted in approx. 870 base pairs for all DNA of C. lunata analyzed, confirming the identification of C. lunata. In vitro, both chitosan nano and non-nano scale effectively inhibited mycelial growth by reducing linear mycelium and biomass and sporulation of C. lunata. In vivo, chitosan nanoscale at 2.0 mg mL⁻¹ greatly reduced the infection and the lesion diameter of C. lunata inoculated fruits after a week and effectively induced defense-related enzyme activity of PO, PPO, and PAL. This report is the first recording of fruit blight and rots on olive caused by C. lunata, as a new disease. Also, we report the in vitro and vivo toxicity of nanoparticles of chitosan as a natural elicitor, effectively inducing defense-related enzymes against C. lunata.

2019 年期间，在埃及 Sohag 大学农学院实验农场种植的树木上的橄榄 ( O. europaea L.) 果实上观察到果枯病和腐烂症状。从有症状的果实中分离出的真菌分离物被鉴定为Curvularia lunata (Walker) Boedijn (两个分离株) 和A. alternata (Fr.) Keissl。（一个隔离）。Koch 的假设通过对受伤的橄榄果实进行体外致病性测试而得到满足，该测试在接种真菌分离株之前在 25 ± 0.2 °C 的潮湿室中孵育一周。在孵化过程中，我们观察到在接种了两种C. lunata分离株的水果上出现了枯萎病和腐烂症状，类似于所描述的自然症状。反过来，A. alternata对橄榄果实无致病性。基于 Clg2p Ras 蛋白基因序列，使用特定的 P1 和 P2 引物对C. lunata 进行PCR 扩增，结果约为 C. lunata 的所有 DNA 的 870 个碱基对分析，证实了C. lunata的鉴定。在体外，壳聚糖纳米和非纳米尺度都通过减少线性菌丝体和生物量以及C. lunata 的孢子形成来有效抑制菌丝体生长。在体内，2.0 mg mL ^{-1 的}壳聚糖纳米级大大降低了C. lunata的感染和病变直径接种一周后的果实，有效诱导 PO、PPO、PAL 的防御相关酶活性。这份报告是首次记录由C. lunata引起的橄榄果疫病和腐烂病，这是一种新病害。此外，我们还报告了壳聚糖纳米粒子作为天然诱导剂的体外和体内毒性，可有效诱导防御相关酶抵抗C. lunata。