设施芹菜光合特性对寡照胁迫的响应

Response of the Photosynthetic Characteristics of Celery to Sparse Sunlight in Greenhouse

以芹菜品种"津南实芹1号"为试材,于2011年3～4月在南京信息工程大学人工控制温室设计寡照试验,测定不同寡照处理和恢复处理的光合参数及荧光参数。结果表明:随着寡照天数的增加,芹菜叶片的最大光合速率、光饱和点、光能初始利用效率显著低于对照,光补偿点逐渐增加;不同的寡照处理下,芹菜叶片最大光合速率与胞间CO2浓度关系最密切,其次与蒸腾速率有关;随着寡照处理天数的增加,芹菜叶片PSⅡ最大量子产量和光合电子传递速率都逐渐降低,非光化学淬灭值qN随着寡照天数增加逐渐增加。结合叶片光合速率和荧光参数,将寡照2～6 d分为轻度灾害(I级),7～11 d分为中度灾害(Ⅱ级),寡照处理12 d以上划分为重度灾害(Ⅲ级)。研究认为芹菜寡照处理第12 d以后,光系统活性受到严重损伤,无法恢复,因此芹菜寡照12 d是受灾的临界指标,研究结果为设施作物寡照气象灾害防御提供依据。

The celery variety ＂Jinnan1Apium graveolens cv＂ was choosed to make sparse sunlight experiment in the artificial control greenhouse of the agrometeorological experiment station in Nanjing University of Information Science Technology from March to April in 2011,and the photosynthesis parameters and fluorescence parameters were measured under different sunlight shortage treatment.The results show that the maximum photosynthetic rate,light saturation point,solar energy initial utilization efficiency were significantly lower than that under natural sunlight with increase of sparse light date,and the light compensation point increased gradually.The maximum photosynthetic rate of celery leaves was closely associated with intercellular CO2 concentration and related with the transpiration rate under different sparse light treatment.The potential of photochemical efficiency（Fv/Fm） and the photosynthetic electron transfer efficiency（ETR） declined but the photochemical quenching（qN） increased evidently when the date of sparse sunshine increased.Combined with photosynthetic rate and fluorescence parameters of celery leaves,the duration of three to six days＇ sparse sunlight can be regarded as mild disaster（grade I）,and seven to eleven day＇s sparse sunlight can be regarded as moderate disaster（grade II）,and twelve days or more for severe disaster（grade III）.It suggests that optical activity suffered serious injury and could not recover after twelve days sparse sunlight.Therefore 12-day in sparse sunlight is critical disaster index for celery.The results in this study could be used to provide scientific basis for protecting facilities agriculture and preventing the meteorological disaster.