Kong Ping, Daughtrey Margery L, Hong Chuanxue
Hampton Roads Agricultural Research and Extension Center, Virginia Tech, Virginia Beach, VA 23455, USA.
Long Island Horticultural Research and Extension Center, Cornell University, Riverhead, NY 11901, USA.
J Fungi (Basel). 2023 Jan 29;9(2):181. doi: 10.3390/jof9020181.
() infects (boxwood), (pachysandra), and spp. (sweet box); yet, how it adapts to its hosts has been unclear. Here, we performed serial passage experiments with the three hosts and measured changes in three aggressiveness components: infectibility, lesion size, and conidial production. The detached leaves of individual hosts were inoculated with isolates (P0) from the originating host, followed by nine serial inoculations of new leaves of the same host with conidia from the infected leaves of the previous inoculation. All boxwood isolates maintained their capability of infection and lesion expansion through the 10 passages, whereas most non-boxwood isolates lost these abilities during the passages. Isolates from plants of origin (-P0) and their descendants isolated from passages 5 (-P5) and 10 (*-P10) were used to evaluate aggressiveness changes on all three hosts with cross-inoculation. While post-passage boxwood isolates gave enlarged lesions on pachysandra, sweet box P5 and pachysandra P10 isolates showed reduced aggressiveness on all hosts. appears to be most adapted to boxwood and less adapted to sweet box and pachysandra. These results suggest speciation of , with its coevolutionary pace with the hosts the fastest with boxwood, intermediate with sweet box, and the slowest with pachysandra.
（某种病菌）感染黄杨属植物、富贵草属植物和野扇花属植物；然而，它如何适应其宿主尚不清楚。在这里，我们对这三种宿主进行了连续传代实验，并测量了三个侵袭性组成部分的变化：感染性、病斑大小和分生孢子产生量。用来自原始宿主的分离株（P0）接种单个宿主的离体叶片，然后用前一次接种感染叶片上的分生孢子对同一宿主的新叶片进行九次连续接种。所有黄杨属植物分离株在10次传代过程中都保持了感染和病斑扩展的能力，而大多数非黄杨属植物分离株在传代过程中失去了这些能力。来自原始植物（-P0）及其从第5代（-P5）和第10代（*-P10）传代中分离出的后代的分离株用于通过交叉接种评估对所有三种宿主的侵袭性变化。虽然传代后的黄杨属植物分离株在富贵草上产生了更大的病斑，但野扇花P5和富贵草P10分离株在所有宿主上的侵袭性都有所降低。（该病菌）似乎最适应黄杨属植物，而对野扇花和富贵草的适应性较差。这些结果表明（该病菌）正在形成物种，其与宿主的共同进化速度在黄杨属植物中最快，在野扇花中居中，在富贵草中最慢。
