Chitarra Walter, Siciliano Ilenia, Ferrocino Ilario, Gullino Maria Lodovica, Garibaldi Angelo
Centre for Innovation in the Agro-Environmental Sector, AGROINNOVA, University of Torino, Largo P. Braccini 2, Grugliasco (TO), Italy.
Department of Agricultural, Forest and Food Sciences (DISAFA), University of Torino, Largo P. Braccini 2, Grugliasco (TO), Italy.
PLoS One. 2015 Oct 15;10(10):e0140769. doi: 10.1371/journal.pone.0140769. eCollection 2015.
The severity of F. oxysporum f.sp. conglutinans on rocket plants grown under simulated climate change conditions has been studied. The rocket plants were cultivated on an infested substrate (4 log CFU g-1) and a non-infested substrate over three cycles. Pots were placed in six phytotrons in order to simulate different environmental conditions: 1) 400-450 ppm CO2, 18-22°C; 2) 800-850 ppm CO2, 18-22°C; 3) 400-450 ppm CO2, 22-26°C, 4) 800-850 ppm CO2, 22-26°C, 5) 400-450 ppm CO2, 26-30°C; 6) 800-850 ppm CO2, 26-30°C. Substrates from the infested and control samples were collected from each phytotron at 0, 60 and 120 days after transplanting. The disease index, microbial abundance, leaf physiological performances, root exudates and variability in the fungal profiles were monitored. The disease index was found to be significantly influenced by higher levels of temperature and CO2. Plate counts showed that fungal and bacterial development was not affected by the different CO2 and temperature levels, but a significant decreasing trend was observed from 0 up to 120 days. Conversely, the F. oxysporum f.sp. conglutinans plate counts did not show any significantly decrease from 0 up to 120 days. The fungal profiles, evaluated by means of polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE), showed a relationship to temperature and CO2 on fungal diversity profiles. Different exudation patterns were observed when the controls and infested plants were compared, and it was found that both CO2 and temperature can influence the release of compounds from the roots of rocket plants. In short, the results show that global climate changes could influence disease incidence, probably through plant-mediated effects, caused by soilborne pathogens.
研究了尖孢镰刀菌黄瓜专化型在模拟气候变化条件下对紫叶生菜植株的危害程度。紫叶生菜植株在受侵染基质（4 log CFU g-1）和未受侵染基质上种植三个周期。花盆放置在六个植物生长箱中，以模拟不同的环境条件：1）二氧化碳浓度400 - 450 ppm，温度18 - 22°C；2）二氧化碳浓度800 - 850 ppm，温度18 - 22°C；3）二氧化碳浓度400 - 450 ppm，温度22 - 26°C；4）二氧化碳浓度800 - 850 ppm，温度22 - 26°C；5）二氧化碳浓度400 - 450 ppm，温度26 - 30°C；6）二氧化碳浓度800 - 850 ppm，温度26 - 30°C。在移栽后0、60和120天，从每个植物生长箱中采集受侵染和对照样本的基质。监测病害指数、微生物丰度、叶片生理性能、根系分泌物以及真菌谱的变化。发现病害指数受较高温度和二氧化碳水平的显著影响。平板计数表明，真菌和细菌的生长不受不同二氧化碳和温度水平的影响，但从0到120天观察到显著的下降趋势。相反，尖孢镰刀菌黄瓜专化型的平板计数从0到120天未显示出任何显著下降。通过聚合酶链反应变性梯度凝胶电泳（PCR-DGGE）评估的真菌谱显示，真菌多样性谱与温度和二氧化碳有关。比较对照植株和受侵染植株时观察到不同的分泌模式，发现二氧化碳和温度都能影响紫叶生菜植株根系化合物的释放。简而言之，结果表明全球气候变化可能通过土壤传播病原体引起的植物介导效应影响病害发生率。
