Studies On Drought Resistance Of Different Regional Amygdalus Pedunculata Pall.

The test materials were selected from Hebei, Wushenqi, Shen mu, Gu yang and Yu yangfive regions’ a yearly growth seedlings Amygdalus pedunculata Pall., then we got their leafanatomical structure characteristics, physiological and biochemical characteristics underdrought stress to determine the drought resistance. The results showed that：（1）The five areas ofAmygdalus pedunculata Pall. are similar in leaf structure. They areall total with cuticle; the vascular bundles are bicollateral; palisade tissues are well developedwith one or two layers. Analysis of variance showed that Hebei region’s blade is the most thinin leaf anatomical structure determination, both the upper epidermis and horny layer areminimum; Yuyang area is on the contrary.（2）In drought damage index, Hebei region’s index is highest, indicating it was damagedbadly, and with worst drought resistance performance; the indexes of Shenmu and Guyangareas are under Hebei and Wushenqi areas; and Yuyang area’s index is minimum, with biggestability to resist drought damage.（3）With the extension of stress time and degree of drought stress, the leaf RWC,plasma membrane permeability and MDA showed an upward trend, and the change range ofweak drought resistance was larger. Their SOD and POD activity, free proline and solubleprotein content with the strengthening of stress increased first then decreased later or directlydecreased, and the stronger drought resistance the higher activity or content.（4）Under water stress the contents of chlorophyll a and b also increased first and thendecreased, and the response of chlorophyll b to drought stress is more sensitive thanchlorophyll a. But Car showed a downward trend, and among them Yu Yang and Shenmuareas were highest after40days.（5）Stomatal density after drought stress has a different degree of increase, which canhelp to adapt to water deficit. But according to the research suggests that the smaller plantstomatal density, the stronger drought-resistant ability. So the drought-resistant ability of YuYang district Amygdalus pedunculata Pall is the strongest.The study indicated that: by adjusting their leaf structure, physiological and biochemicalcharacteristics, Amygdalus pedunculata Pall. reduced the harm caused by water stress, and according to the comprehensive analysis of the indicators we came to a conclusion that thesequence of drought resistance of five regions Amygdalus pedunculata Pall. was as follow:Yuyang area> Shenmu area>Guyang area> Wushenqi area> Hebei area. The research laid afoundation for further breeding, and provided a theoretical basis for the industrializationdevelopment of Amygdalus pedunculata Pall..