Alternaria alternata (Fr.) Keissl. is an important pathogen of litchi (Litchi chinensis Sonn.) that causes blight of leaf, panicle and fruits. Ecophysiological determinants favouring growth and sporulation are keys to understand the pathogen behaviour. Therefore, studies were conducted to assess the effect of different medium, carbon source, pH, temperature, relative humidity and exposure to UV radiation on growth and sporulation of A. alternata under in vitro conditions. Results showed that the maximum mycelia growth rate was on Host Leaf Extract Dextrose Agar but sporulation was the maximum on Potato Dextrose Agar medium. The mycelia growth was more with dextrose as carbon source but the maximum dry weight was recorded in maltose amended medium. Optimum pH for mycelia growth was 6.0, and below or above this pH, mycelia growth was slow. It was evident that the maximum mycelia growth rate and germination of conidia were at 30 °C. The thermal death point of A. alternata was found to be 45 °C with 10 min. exposure. The maximum mean growth rate and germination percent was recorded at 100% relative humidity. The growth rate decreased with increasing exposure time to UV‑B rays up to 20 min, but at exposure time 25 and 30 min, colony changed to profuse mycelia growth with smaller sporulating zone in the centre compared to untreated dishes. The findings of the study will be helpful in understanding epidemiology and devising management strategies of this disease.

链格孢（Alternaria alternata）（神父）是荔枝的重要病原体（荔枝组织神经）引起叶，穗和水果的疫病。有利于生长和孢子形成的生态生理学决定因素是了解病原体行为的关键。因此，进行了研究，以评估不同培养基，碳源，pH，温度，相对湿度和暴露于UV辐射对大豆生长和孢子形成的作用A.孢下体外条件。结果显示最大菌丝体生长速率在寄主叶提取物葡萄糖琼脂上，而孢子形成在马铃薯葡萄糖琼脂培养基上最大。以葡萄糖为碳源的菌丝体生长更多，但在麦芽糖改良培养基中记录了最大干重。菌丝体生长的最佳pH为6.0，低于或高于此pH值，菌丝体生长缓慢。显然，最大菌丝体生长速率和分生孢子萌发在30°C。热死点格孢被发现在45°C下持续10分钟。接触。在100％相对湿度下记录了最大平均增长率和发芽率。随着暴露于20分钟的UV-B射线时间的增加，生长速率降低，但在25和30分钟的暴露时间，菌落发生变化，与未处理的培养皿相比，菌丝体生长迅速，中心的孢子形成区域更小。该研究的结果将有助于理解流行病学和制定该疾病的治疗策略。