Delalibera Italo, Humber Richard A, Hajek Ann E
Department of Entomology, Cornell University, Ithaca, NY 14853, USA.
Can J Microbiol. 2004 Aug;50(8):579-86. doi: 10.1139/w04-041.
Neozygites tanajoae has recently been described as a new fungal pathogen distinct from Neozygites floridana. This pathogen is currently being used as a classical biological control agent against the cassava green mite, Mononychellus tanajoa (Bondar), in Africa. Neozygites tanajoae is a particularly fastidious species, and in vitro cultures of isolates from Brazil and Africa have only recently been established. In this study, the efficacy of several cryoprotectants at different exposure times, cooling rates, and warming rates for protecting hyphal bodies of N. tanajoae during cryopreservation was investigated. A protocol for preservation of cultures of N. tanajoae at ultra-low temperatures of -80 degrees C or -196 degrees C, using 1% trehalose + 2% dimethyl sulfoxide as cryoprotective agents, is described in detail. In this study, we demonstrate that N. tanajoae differs remarkably from N. floridana (isolates ARSEF 662 and ARSEF 5376) in the ability to withstand the stress of cold temperature (4 degrees C) and cryopreservation. In vitro cultures of the 2 N. floridana isolates remained viable at 4 degrees C for up to 47 d; however, cultures of N. tanajoae did not survive this temperature for 4 d. Cryopreservation methods successful for N. tanajoae isolates are not suitable for N. floridana and are unusual in comparison to those for many fungi.
塔纳霍新接霉最近被描述为一种不同于佛罗里达新接霉的新型真菌病原体。这种病原体目前正被用作非洲木薯绿螨（Mononychellus tanajoa (Bondar)）的经典生物防治剂。塔纳霍新接霉是一种特别挑剔的物种，来自巴西和非洲的分离株的体外培养直到最近才得以建立。在本研究中，研究了几种冷冻保护剂在不同暴露时间、降温速率和升温速率下对塔纳霍新接霉菌丝体在冷冻保存过程中的保护效果。详细描述了一种使用1%海藻糖 + 2%二甲基亚砜作为冷冻保护剂在 -80℃ 或 -196℃ 的超低温下保存塔纳霍新接霉培养物的方案。在本研究中，我们证明塔纳霍新接霉在耐受低温（4℃）和冷冻保存压力的能力方面与佛罗里达新接霉（分离株ARSEF 662和ARSEF 5376）有显著差异。两种佛罗里达新接霉分离株的体外培养物在4℃ 下可存活长达47天；然而，塔纳霍新接霉的培养物在这个温度下4天内就无法存活。对塔纳霍新接霉分离株成功的冷冻保存方法不适用于佛罗里达新接霉，并且与许多真菌的冷冻保存方法相比并不常见。
