[目的]采用傅里叶变换红外光谱对葱蒜锈病叶进行了研究,探讨中红外光谱在作物病害诊断中的应用潜力。[方法]用傅里叶变换红外光谱测试了葱蒜正常绿叶及锈病叶,分析其光谱差异。[结果]葱、蒜绿叶的红外光谱主要显示了多糖类物质、蛋白质、酯类振动;正常绿葱蒜叶和锈病葱蒜叶光谱在1800~900cm-1指纹范围显示了差异,与正常绿叶相比,锈病葱叶在1640cm-1的酰胺Ⅰ振动峰变强,在1103cm-1处的肩峰不明显;锈病叶的吸收强度比A1640/A1063、A1640/A1736、A1640/A2924和A1063/A2924比正常叶相应比值A1638/A1059、A1638/A1738、A1638/A2922和A1059/A2922变大。正常蒜叶的多糖振动峰1056cm-1为指纹区的最强峰,而锈病叶在1634cm-1处峰为指纹区的最强峰;锈病蒜叶的吸收强度比A1634/A1069、A1634/A1099、A1409/A2923和A1634/A1737较正常叶的相应比值A1627/A1056、A1627/A1104、A1411/A2920和A1627/A1740变大,锈病叶的A1634/A2923、A1069/A2923和A1737/A2923较相应正常叶的A1627/A2920,A1056/A2920,A1740/A2920变小。[结论]根据红外光谱差异可以区分绣病叶与正常叶,红外光谱可望发展成为作物病害检测的方法。
[ Objective] Fourier transform infrared spectroscopy was used to study fistular onion (Alliumfistulosum) and garlic (Allium sativum) rust leaves, so as to explore the application potential of mid-infrared spectroscopy in the diagnosis of crop disease. [ Method] The normal green leaves and rust leaves of fistular onion and garlic were tested using fourier transform infrared spectroscopy, and their spectral differences were analyzed. [ Result] The infrared spectra of green leaves of fistular onion and garlic are mainly composed of the vibrational bands of polysaccharides, protein and ester. Normal and rust leaves exhibited differences in the fin- gerprint interval of 1 800 -900 cm-1 , in which the band at 1 640 cm-1 in the spectrum of flstular onion rust leaf became stronger, and the band at 1 103 cm-1 was not obvious compared with the spectrum of normal leaf. The absorbance ratios A1640/A1063, A1640/A1736, A1640/A2924, and A1063/A2924 of onion rust leaf were larger than the corresponding ratios A1638/A1 059, A1738/A1 38, A2921/A1638, and A2 92l/A1059 in the spectrum of normal leaf. The band of polysaccharides at 1 056 cm-1 in the spectrmn of garlic normal leaf was the strongest in fingerprint area, while the band at 1 634 cm-1 in the spectrum of garlic rust leaf was the strongest in that are- a. The absorbance ratios A1634/A1069 , A1634/A1099 , A1409/A2923 , and A1634/A737 of garlic rust leaf were larger than the corresponding ratios A1627/A1056 , A1623/A1104 , A1411/A2920 and A1627/A1740 of normal leaves. While the ratios A1634/A2923, A1059/A2923, and A1737/A2923 of garlic rust leaf were less than the corresponding values of A1627/A2920, A1056/A2920, and A1 740/A2920 of normal leaf. [ Conclusion] Rust leaf and normal leaf could be distinguished according to the differences in infrared spectra, and infrared spectroscopy could be developed as the detection method for crop diseases.