‘黄金梨’果肉硬化症的果实显微结构观察

Observation of the Flesh Microstructure for Hard-End Disorder of 'Whangkeumbae' Pear(Pyrus pyrifolia Nakai)

本文以‘黄金梨'硬化症病果和正常果为试材,采用常规的石蜡切片法,比较了硬化症病果果肩部(SE)、果顶部(CE)以及正常果果肩部(CKSE)和果顶部(CKCE)的表皮及果肉的解剖结构差异。结果表明,CKSE和CKCE的角质层薄,随表皮细胞的生长出现不同程度的起伏,单宁细胞层平均为3～4层;SE和CE的角质层和单宁细胞层细胞相对较厚。‘黄金梨'的表皮层和单宁细胞层细胞的横径长度均大于纵径,但CE和SE的纵/横比值均高于CKSE和CKCE,说明病果的细胞形状发生了变化,逐渐接近于圆形或椭圆形,尤其是硬化症症状严重的果顶部。果肉硬度大小依次是CE>SE>CKCE>CKSE;CKCE、CKSE和SE果肉中石细胞团直径较CE大;CKSE和CKCE的团围薄壁细胞的长度比SE和CE的长。

The experiment was carried out in ‘Whangkeumbae’ pear fruits with or without hard-end disorder. The differences of fruit pericarp and flesh microstructure were compared between stem end （SE） or calyx end （CE） in hard-end disorder fruits ana stem end （CKSE） or calyx end （CKCE） in normal fruits by using paraffin section method. The results showed that the corneous layer in CKSE and CKCE, which was variation as the fruit growth, was thinner than in CE and SE. There were 3-4 tannin layers in CKSE and CKCE. However, there were thicker corneous layer cells and tannin layer cells in CE and SE compared to CKCE and CKSE. Horizontal diameter length of epidermis and corneous layer cells were greater than vertical diameter length in ＇Whangkeumbae＇ pear, but the ratio of vertical and horizontal diameter in CE and SE were higher than CKCE and CKSE. The results indicated that the shape of fruit cells with hard-end disorder gradually changed to round or oval, and the symptom in CE was especially obvious. The hardness order is CE〉SE〉CKCE〉CKSE. Diameters of sclereid group of CKCE, CKSE and SE were bigger than CE. The parenchyma cells surround regiment of CKSE and CKCE were longer compared to SE and CE.