Costa-Arbulú C, Gianoli E, Gonzáles W L, Niemeyer H M
Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile.
J Chem Ecol. 2001 Feb;27(2):273-83. doi: 10.1023/a:1005676321251.
Feeding by the aphid Sipha flava produces a reddish spot on mature leaves of Sorghum halepense. The present work is aimed at determining whether this plant response entails induced resistance against the aphid. Old and young leaves showed the same response to aphid feeding (reddish coloration). Water-stressed plants displayed a similar reddish coloration to aphid-infested plants. This was verified by evaluation of absorbance peaks of the respective leaf extracts. Aphid fecundity was reduced on previously infested (and hence reddish colored) leaves. However, aphid fecundity was not affected on water stressed plants. Furthermore, aphid survival was not different on artificial diets containing increasing concentrations of the reddish pigment. It is concluded that the reddish spot is correlated with, but is not itself responsible for, the observed induced resistance of S. halepense against S. flava.
黄腹缢管蚜取食会在石茅高粱的成熟叶片上产生一个红色斑点。目前的研究旨在确定这种植物反应是否会引发对该蚜虫的诱导抗性。老叶和嫩叶对蚜虫取食表现出相同的反应（红色着色）。水分胁迫的植株与受蚜虫侵害的植株呈现出相似的红色。通过评估各自叶片提取物的吸收峰对此进行了验证。在先前受侵害（因此呈现红色）的叶片上，蚜虫的繁殖力降低。然而，水分胁迫植株上的蚜虫繁殖力并未受到影响。此外，在含有浓度不断增加的红色色素的人工饲料上，蚜虫的存活率没有差异。得出的结论是，红色斑点与观察到的石茅高粱对黄腹缢管蚜的诱导抗性相关，但红色斑点本身并非诱导抗性的原因。
