This study aimed at evaluating the effect of environmental factors temperature and water potential (Ψw) on the growth of Neocosmospora (Fusarium) solani and three Fusarium species (F. oxysporum, F. equiseti and F. brachygibbosum) associated with citrus dry root rot and to determine the optimum and marginal rate for their growth. The effects of incubation temperature (5–40 °C), water potentials (Ψw) (− 15.54; − 0.67 MPa) (0.89–0.995 a_w) and their interaction (5–30 °C) was evaluated on the in vitro radial growth rates of Fusarium spp. and on their lag phase. Secondary models were used to model the combined effect of these factors on radial growth rate. The results underlined a highly significant effects (P < 0.001) of Ψw and temperature and their interactions on radial growth rates and lag phases (λ). The Four studied species were shown tolerant to a temperature of 35 °C with an optimum mycelial growth at 30 for N. solani and F. oxysporum and at 25 °C for F. equiseti and F. brachygibbosum. However, no growth was observed at both temperatures 5 and 40 °C and at Ψw of − 9.68 MPa (0.93 a_w). The optimum water potential for growth was ≥− 2.69 MPA (>0.98 a_w). The results from the polynomial model and response surface showing good agreement between observed and predicted values. The external validation on citrus fruit indicated slight differences between predicted and observed values of radial growth. The results of this study will be beneficial for understanding the ecological knowledge of these species and thereby limited preventively their occurrence.

本研究旨在评估环境因素温度和水势 ( Ψ w) 对与柑橘干根腐病相关的新孢子菌( Fusarium ) solani和三种镰刀菌( F. oxysporum、F. equiseti和F. brachygibbosum)生长的影响并确定它们的最佳和边际增长率。孵化温度 (5 – 40 °C)、水势 ( Ψ w) ( −  15.54; −  0.67 MPa) (0.89 – 0.995  a _w ) 及其相互作用 (5 –30 °C) 对镰刀菌属的体外径向生长速率进行了评估。并处于滞后阶段。二级模型用于模拟这些因素对径向增长率的综合影响。结果强调了Ψ w 和温度及其相互作用对径向生长速率和滞后阶段 ( λ )的高度显着影响 ( P  < 0.001 )。四个研究的物种显示出耐受 35°C 的温度，对于N. solani和F. oxysporum，最佳菌丝生长在 30 °C，对于木贼和F. brachygibbosum的最佳菌丝生长在 25°C 。然而，在 5°C 和 40°C 以及Ψ下均未观察到生长w of − 9.68 MPa (0.93  a _w )。生长的最佳水势为≥− 2.69 MPA (>0.98  a _w )。多项式模型和响应面的结果显示观测值和预测值之间具有良好的一致性。柑橘类水果的外部验证表明径向生长的预测值和观察值之间存在细微差异。本研究的结果将有助于了解这些物种的生态知识，从而预防性地限制它们的发生。