Study on the Physiological Quality Changes and Identification of Pathogen Pathogenicity of Gastrodia elata after Harvest

"Dafang" Gastrodia elata was used as the test material to determine the changes of 17 physiological quality indicators(hardness,respiration intensity,moisture content,extrachromic,intrachromic,soluble solids,protein,polysaccharide,gastrodin,adenosine,p-Hydroxybenzyl alcohol,p-Hydroxybenzaldehyde)and identify the pathogens during storage period,and analysis of the correlation and principal component of various physiological quality indicators were carried out. The results showed that the polysaccharides,gastrodin,adenosine,p-hydroxybenzyl alcohol and p-hydroxybenzaldehyde of Gastrodia elata were 241.36 mg·g^-1,632.46,76.48,186.82,6.07 μg·g^-1,respectively,stored at low temperature(25±0.5)℃ for 30 d. However,the polysaccharides,gastrodin,adenosine,p-hydroxybenzyl alcohol and p-hydroxybenzaldehyde of Gastrodia elata were 225.28 mg·g^-1,603.32,71.32,173.32,5.32 μg·g^-1,respectively,stored at low temperature(1±0.5)℃. Therefore,low temperature(1±0.5)℃ could delay the change of physiological quality of fresh gastrodia elata after harvest. It was suggested that the refrigeration temperature of storing Gastrodia elata should be 0~1℃. The respiratory type of Gastrodia elata was climacteric respiration. The main pathogens of Gastrodia elata were Neofusicoccum(Neofusicoccum sp.),Diaporthe(Diaporthe sp.),Alternaria(Alternaria sp.)and Fusarium(Fusarium sp.). The correlation analysis showed that the postharvest physiological quality of Gastrodia elata was well correlated,and the nutritional indexes(gastrodin,adenosine,p-hydroxybenzyl alcohol and p-hydroxybenzaldehyde)of Gastrodia elata were significantly positively correlated with each other(P<0.01). In addition,a comprehensive evaluation function of 17 physiological quality indicators of Gastrodia elata was established by principal component analysis,which was used to evaluate the changes of storage quality of Gastrodia elata.