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经对菠萝果肉的分析,发现病果的PPO(多酚氧化酶)、POD(过氧化物酶)活性和天然底物绿原酸、单宁含量远较正常果为高,而有机酸和抗坏血酸含量,则病果较正常果为低。将果肉提取的PPO与外源绿原酸、单宁相作用,所形成的褐色产物的紫外吸收光谱和菠萝黑心组织提取液的紫外吸收光谱相同,这证明酶促褐变是菠萝黑心的重要发病机理之一。菠萝褐变的外因是气温的急剧变化,内因则是果肉营养比的不平衡,如氮、钾与钙间的不平衡,既能影响细胞结构和膜的透性,又能影响酶的活性和有机酸、抗坏血酸的含量。在内外因的共同作用下,细胞易受损伤破裂,细胞、液胞中的酚类物质外溢,与PPO和氧相遇,被氧化成褐黑色醌类而褐变。所以,在生产上。控制果实营养比,尤其在偏施氮肥或偏施钾肥的地区,适当控制氮、钾的施用,并适当增施钙肥,对有效控制菠萝黑心病发生,有着积极意义。
The pineapple pulp analysis showed that PPO (polyphenol oxidase), POD (peroxidase) activity and the natural substrate chlorogenic acid, tannin content of the disease fruit is much higher than normal fruit, and organic acids and ascorbic acid Content, the disease is lower than the normal fruit. The results showed that enzymatic browning was an important pathogenesis of pineapple black heart when the PPO extracted from the pulp was treated with exogenous chlorogenic acid and tannin and the UV absorption spectrum of the brown product formed was the same as that of the black pineapple tissue extract One of the mechanisms. The external cause of pineapple browning is a dramatic change in temperature. The internal cause is the imbalance of the nutrient ratio of the pulp, such as the imbalance between nitrogen, potassium and calcium, which can affect the cell structure and membrane permeability as well as the enzyme activity Organic acids, ascorbic acid content. Under the combined action of internal and external factors, the cells are vulnerable to rupture, the phenolics in the cells and liquid cells spill, meet with PPO and oxygen, and are oxidized into brown black quinones and browning. So, in production. Control of fruit nutrition ratio, especially in areas with partial or partial potassium application, proper control of nitrogen and potassium application and proper application of calcium fertilizer have positive significance for the effective control of black pineapple disease.