Oghaz N Akbari, Hatamzadeh S, Rahnama K, Moghaddam M Khorrami, Vaziee S, Tazik Z
Department of Plant Protection, Faculty of Plant Production, Gorgan University of Agricultural Science & Natural Resources, Gorgan, 4918943464, Golestan, Iran.
Department of Horticultural Sciences, Faculty of Plant Production, Gorgan University of Agricultural Science & Natural Resources, Gorgan, 4918943464, Golestan, Iran.
World J Microbiol Biotechnol. 2022 Aug 12;38(10):183. doi: 10.1007/s11274-022-03356-8.
Cladosporium spp. are among the most important plant pathogens, plant endophytes, insect parasites and human pathogens in nature. The aim of this study was to increase the speed and accuracy of Cladosporium spp. spore counting using UV-visible spectrophotometry based on the regression model in a water suspension. Spores of C. ramotenellum AM55, C. limoniforme Br15, C. tenuissimum K15 and C. cladosporioides Ld13 fungi were diluted in sterile distilled water several times. Spore concentration/ml (SC) was counted with a hemocytometer. The spectrophotometer visible light absorption (ABS) was measured under 14 wavelengths from 300 to 950 nm for each dilution. The results showed that the morphological variation of the spores greatly affect the determination of the suitable wavelength. 650, 750, 500 and 400 nm wavelengths had the highest coefficient of determination (R) values respectively for C. ramotenellum AM55, C. limoniforme Br15, C. tenuissimum K15 and C. cladosporioides Ld13 on the linear regression model. R values were 0.9874, 0.9647, 0.8856 and 0.9711 respectively, for the 650, 750, 500 and 400 nm wavelengths. The linear equation of SC = 10 × ABS-133,040 with the highest R2 value of 0.9532 had the best fit under a combinatorial regression model where SC and ABS of all Cladosporium spp. were presented. The proposed linear regression models can be used under in vivo and in vitro conditions for medicine or plant pathology studies which certainly increase the accuracy and speed of the future experiments compared to the hemocytometer method.
枝孢属真菌是自然界中最重要的植物病原体、植物内生菌、昆虫寄生虫和人类病原体之一。本研究的目的是基于水悬浮液中的回归模型，利用紫外可见分光光度法提高枝孢属真菌孢子计数的速度和准确性。将悬铃木枝孢AM55、柠檬形枝孢Br15、细弱枝孢K15和枝孢霉Ld13真菌的孢子在无菌蒸馏水中多次稀释。用血细胞计数器计数每毫升孢子浓度（SC）。对每种稀释液在300至950nm的14个波长下测量分光光度计可见光吸收（ABS）。结果表明，孢子的形态变化对合适波长的测定有很大影响。在直线回归模型中，650、750、500和400nm波长分别对悬铃木枝孢AM55、柠檬形枝孢Br15、细弱枝孢K15和枝孢霉Ld13具有最高的决定系数（R）值。650、750、500和400nm波长的R值分别为0.9874、0.9647、0.8856和0.9711。在组合回归模型中，当呈现所有枝孢属真菌的SC和ABS时，SC = 10×ABS - 133040的线性方程具有最高的R²值0.9532，拟合效果最佳。所提出的线性回归模型可用于体内和体外条件下的医学或植物病理学研究，与血细胞计数器法相比，这肯定会提高未来实验的准确性和速度。
