Šišić Adnan, Baćanović-Šišić Jelena, Karlovsky Petr, Wittwer Raphaël, Walder Florian, Campiglia Enio, Radicetti Emanuele, Friberg Hanna, Baresel Jörg Peter, Finckh Maria R
Department of Ecological Plant Protection, University of Kassel, Witzenhausen, Germany.
Section of Organic Plant Breeding and Agrobiodiversity, University of Kassel, Witzenhausen, Germany.
PLoS One. 2018 Feb 14;13(2):e0191969. doi: 10.1371/journal.pone.0191969. eCollection 2018.
Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI) of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea.
豆科覆盖作物和活地被植物不仅在为农业生态系统提供多种有益服务方面具有巨大潜力，而且还可能通过共享病原体，尤其是镰刀菌属的病原体，给轮作中的其他作物带来病理风险。2013年和2014年评估了作为覆盖作物和活地被植物在五个欧洲地点种植的地下三叶草、白三叶草、冬巢菜和夏巢菜根部的病害严重程度，以及从根部回收的镰刀菌属对豌豆的频率、分布和侵袭性。所有地点的病害症状都非常轻微。然而，在1480条无症状根中，分离出了14种镰刀菌属的670个分离株。在这两年中，从所有寄主中最常分离出的物种是尖孢镰刀菌和燕麦镰刀菌，占总分离百分比的69%。它们在瑞士、意大利和德国的地点很常见，而在瑞典的地点，尖孢镰刀菌占主导地位，燕麦镰刀菌很少出现。对六种镰刀菌属的72个分离株在温室试验中测试了其对豌豆生物量的侵袭性和影响。燕麦镰刀菌的分离株引起严重的根腐症状，平均严重程度指数（DI）为82，与未接种对照相比，平均生物量减少74%。尖孢镰刀菌和茄病镰刀菌的分离株在侵袭性及其对豌豆生物量的影响方面变化很大。DI在15至50之间变化，相对于未接种对照的生物量变化为-40%至+10%。三线镰刀菌、锐顶镰刀菌和木贼镰刀菌的分离株无侵袭性或侵袭性较弱，常增加豌豆生物量。这项研究表明，一些主要的豌豆病原体具有高度的生态可塑性，能够内生定殖在所研究的寄主中，因此可能成为豌豆等易感主要豆科谷物作物的接种体库。
