Pugliese M, Gullino M L, Garibaldi A
Centre of Competence for the Innovation in the agro-environmental field (AGROINNOVA) - University of Torino, Via L. da Vinci, 44, IT-10095 Grugliasco (TO) - Italy.
Commun Agric Appl Biol Sci. 2011;76(4):579-82.
Plant responses to elevated CO2 and temperature have been much studied in recent years, but effects of climate change on pathological responses are largerly unknown. The pathosystems grapevine (Vitis vinifera) - downy mildew (Plasmopara viticola) and powdery mildew (Erysiphe necatrix) were chosen as models to assess the potential impact of increased CO2 and temperature on disease incidence and severity under controlled environment. Grapevine potted plants were grown in phytotrons under 4 different simulated climatic conditions: (1) standard temperature (ranging from 18 degrees to 22 degrees C) and standard CO2 concentration (450 ppm); (2) standard temperature and elevated CO2 concentration (800 ppm); (3) elevated temperature (ranging from 22 degrees to 26 degrees C, 4 degrees C higher than standard) and standard CO2 concentration; (4) elevated temperature and CO2 concentration. Each plant was inoculated with a spore suspension containing 5x10(5) cfu/ml. Disease index and physiological parameters (chlorophyll content, fluorescence, assimilation rate) were assessed. Results showed an increase of the chlorophyll content with higher temperatures and CO2 concentration, to which consequently corresponded an higher fluorescence index. Disease incidence of downy mildew increased when both CO2 and temperatures were higher, while an increase in CO2 did not influenced powdery mildew incidence, probably due to the increased photosynthetic activity of plants under such conditions. Considering that the rising concentrations of CO2 and other greenhouse gases will lead to an increase in global temperature and longer seasons, we can assume that this will allow more time for pathogens evolution and could increase pathogen survival, indirectly affecting downy and powdery mildews of grapevine.
近年来，植物对二氧化碳浓度升高和温度升高的反应已得到大量研究，但气候变化对病理反应的影响在很大程度上仍不清楚。选取葡萄（葡萄属）-霜霉病（葡萄生单轴霉）和白粉病（葡萄白粉菌）这两种病原体系作为模型，以评估在可控环境下二氧化碳浓度升高和温度升高对疾病发病率和严重程度的潜在影响。将盆栽葡萄植株种植在人工气候室中，设置4种不同的模拟气候条件：（1）标准温度（18摄氏度至22摄氏度）和标准二氧化碳浓度（450 ppm）；（2）标准温度和升高的二氧化碳浓度（800 ppm）；（3）升高的温度（22摄氏度至26摄氏度，比标准温度高4摄氏度）和标准二氧化碳浓度；（4）升高的温度和二氧化碳浓度。每株植物接种含5×10⁵ cfu/ml的孢子悬浮液。评估疾病指数和生理参数（叶绿素含量、荧光、同化率）。结果表明，随着温度和二氧化碳浓度升高，叶绿素含量增加，相应地荧光指数也更高。当二氧化碳浓度和温度都较高时，霜霉病的发病率增加，而二氧化碳浓度升高并未影响白粉病的发病率，这可能是由于在此条件下植物光合活性增强。考虑到二氧化碳和其他温室气体浓度的上升将导致全球气温升高和生长季节延长，我们可以推测这将使病原体有更多时间进化，并可能增加病原体的存活率，从而间接影响葡萄的霜霉病和白粉病。
