香蕉采后炭疽病发生与几丁酶、β-1,3-葡聚糖酶和多巴胺的关系

Incidence of Anthracnose in Relation to Chitinase, β-1, 3-Glucanase and Dopamine of Banana Fruits After Harvest

几丁酶、β－1，3-葡聚糖酶随着香蕉术后炭疽病的发展过程，活性逐渐增加；但当果实出现明显病害症状时活性略有下降。施保功处理在抑制香蕉采后炭疽病发生的同时也抑制了芭蕉炭疽菌可能诱导的几丁酶和β-1，3-葡聚糖酶活性的增加。多巴胺在香蕉采收时含量较高，但随着炭疽病的发生明显下降。对“黑油身”和“63－1”两个不同抗病品种分析表明，前者几丁酶和β－1，3-葡聚糖酶活性和多巴胺含量较高与其较强的抗病性相一致。

The incidence of anthracnosecaused by Colletotrichum musae on bananafruitS after harvest was investigatedwhen the fruits were dipped in a solution of ethrel 1 000 mg/L for 1 minand allowed to ripen for 5 d at 20℃and RH 80% - 90% prior to shelf Period at ambient temperature (25 -30℃ ) and RH 55%- 65%. The apPearance of disease symptoms was related to the physiological condition of thefruits. The activities of chitinasq and β-1, 3-glucanase increased gradually during pathogenesis. However, it decreased a little when the fruits showedobvious disease symptoms (Fig. 1 ).The treatment with sporgon at a concentration of 1 mg/L suppressed boththe development of anthracnose and theincreases of chitinase and p-1, 3-glucanase activities (Table 1 ), a fact suggesting that pathogenesis enhanced theactivities of the two enzymes. The content of dopamine in banana Peel washigh (1. 28 mg/g FW)at harvest, andthen decreased markedly during the incidence of anthracnose (Fig. 3 ). Compared with the variety ' 63- 1', the activities of chitinase and β-1, 3-glucanase and the content of dopaminewere higher in the variety 'Black-oilshape'(Table 2), which might be asso-elated with a stronger resistance to thediseases.