叶片微形态结构特征与柑橘溃疡病抗性相关性研究

为了研究叶片微结构特征与柑橘溃疡病抗性的关系。选用罗浮金柑、新生系3号椪柑、纽荷尔脐橙及星露比葡萄柚这四个分别被认为是对柑橘溃疡病具有高抗、抗、耐和高感特性的品种，通过涂抹接种法来在实验室验证其抗病性；采用扫描电镜及树脂包埋半薄切片等技术对上述品种的成熟叶片下表皮气孔及叶片显微解剖结构进行观察测量；将健康叶片浸泡在菌液中，采用细菌分离法来观察同样条件下通过气孔进入不同柑橘品种叶片体内的活细菌数。结果：四个品种对溃疡病抗性存在显著差异；不同品种间气孔密度、气孔大小、叶片厚度、栅栏组织厚度、海绵组织厚度、下皮层厚度也存在差异，其中气孔密度差异达到极显著；健康叶片浸泡接种溃疡病后，分离到的单菌落数的顺序依次是星露比葡萄柚>纽荷尔甜橙>新生系3号碰柑>罗浮金柑。因此，气孔密度对柑橘品种抗病性的解释量极高。

Correlation between Citrus Canker Resistance and Leaf Micro-morphological Characteristics in Citrus

This study was to reveal the relations between leaf micro-morphological characteristics and citrus canker resistance in citrus. Different micro-morphological characteristics related to intensity of citrus canker in four citrus varieties differing in their degree of resistance to citrus canker were investigated. After healthy leaves were immersed in suspension culture solution with citrus canker bacteria for 2 hours, the number of the bacteria in specific leaf area was counted by method of bacteria isolation. These four citrus varieties were resistant to citrus canker differently. There were significant differences between stomatal density in all the citrus varieties tested. Less number of bacteria was detected in resistant varieties than that in susceptible ones. The stomatal density in abaxial leaf epidermis can be used as a prediction marker toward disease resistance.