Different root low temperature response of two maize genotypes differing in chilling sensitivity

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• 作者：Aroca ; Ricardo ; Tognoni ; Franco ; Irigoyen ; Juan José ; Sá ; nchez-Dí ; az ; Manuel ; et. al.
• 关键词：chilling ; low temperature acclimation ; mercuric chloride ; root hydraulic conductance ; water channels ; Zea mays ; CRHC ; composite root hydraulic conductance ; E ; leaf transpiration rate ; J_v ; exuded sap water flow ; L_h ; hydrostatic root h
• 刊名：Plant Physiology and Biochemistry
• 出版年：2001
• 出版时间：December, 2001
• 年：2001
• 卷：39
• 期：12
• 页码：1067-1073
• 全文大小：120 K

文摘

Here we report on the root hydraulic properties of intact and excised root systems of two maize genotypes differing in chilling sensitivity (Z7, tolerant and Penjalinan, sensitive) subjected for 3 d to 5 °C. When root hydraulic conductance (L) was measured under a hydrostatic force using an excised root system in a pressure chamber, an initial decrease of L was observed in both genotypes. However, the value of L increased in the chilling tolerant genotype after 30 h at 5 °C; in the chilling sensitive Penjalinan genotype there was no such increase. Osmotic root hydraulic conductance was measured in excised root systems exuding under atmospheric pressure. We observed a progressive decline during the chilling treatment of the osmotic root hydraulic conductance in the chilling sensitive Penjalinan plants; however, after 54 h at 5 °C, the chilling tolerant Z7 plants had a significantly higher osmotic hydraulic conductance. Moreover, in the chilling tolerant plants we found an increase in the inhibition caused by HgCl₂ of the osmotic hydraulic conductance during the chilling treatment, indicating a possible increase in the contribution of aquaporins to root hydraulic conductance in the chilling tolerant Z7 plants during chilling treatment.