The Changes Of Cell Wall Component And Stone Cell’s Morphological Observation During Japanese Pear’s Maturation

The ripening and softening of fruits are a complex physiological and biochemical process.Including that the increase of weight, horizontal, lengthwise size and flavor and texture. The change offruits’texture is the most obvious sign in the growth and maturity. This is also the shared characteristicsof all kinds of fruits. The fruits’ ripening and softening, on the one hand, because of the enzyme thatdegradation cell wall plays a part in cell wall. On the other hand, the changes of cell wall’s structureand component. The cell wall consists of cellulose, hemicellulose and pectin and so on. In the growthcycle of fruits, cell wall’s structure and component has changed. These changes lead to the maturity offruit. However, the changes are different because of the variety and strain. Japanese pears: Nijyuseiki,kousui and cyoujyuurou were used as experimental materials. This experiment studied and analysed thefundamental physiological index, the changes of cell wall’s component and the morphology change ofstone cell in nijyuseiki. The results were as follows:1The fruits’ fundamental physiological indexThis experiment studied the changes of weight by weighing method. The results showed that: thethree varieties’growth has presented single S style. Among August17th to the maturity, kousui’s weightincreased rapidly, nijyuseiki and cyoujyuurou slower than kousui. The horizontal and lengthwise sizewas measured with vernier method. The results showed that: three varieties’ horizontal and lengthwisesize have presented single S style. Among August17th to the maturity, kousui’s horizontal andlengthwise size increased rapidly, nijyuseiki and cyoujyuurou slower than kousui.2The changes of pulp cell wall’s materialThis experiment measured the content of Ethanol Insoluble Solid by weighing method. Showedthat: three varieties’content increased and then decreased. In initial stage, the content of cyoujyuurou’sEIS increased rapidly. The maturation period’s content was three varieties’ minmum value.The content of cellulose and ligin were weighed by weighing method. The results showed that: interms of cellulose, before June10th, the cyoujyuurou’s content was higher than the others’. From June10th to July second, the content of kousui increased rapidly.And from July second, the content ofkousui was higher than the others’; in terms of ligin, three varieties’ content increased and thendecreased. But there were difference, nijyuseiki and cyoujyuurou decreased in June10th, kousui decreased in May24th. From July second to July25th, kousui’s drop was maximum value.The content of hemicellulose was measured by Anthrone method. The results showed that: interms of4%KOH hemicellulose’s content, nijyuseiki and kousui decreased and then increased. But thestage and range were different. Cyoujyuurou’s content decreased the whole stage; in terms of24%KOHhemicellulose’s content, nijyuseiki, kousui and cyoujyuurou decreased and then increased.The stageand range were different. Three varieties’ hemicellulose had presented decreased and then increased.The content of pectin was measured by Carbazole method. The results showed that: in the wholestage, the content of there varieties’ Water soluble pectinⅡ, EDTA soluble pectin and Na2CO3solublepectin increased. Nijyuuseiki and kousui’s Water soluble pectinⅠincreased, but cyoujyuurou hadunobvious changes. And the content of Na2CO3soluble pectin was higher than the others’. Pectin’scontent increased in the whole stage.3The morphological observation of pulp stone cell in nijyuuseikiFrom the initial stage to maturation stage, observed the change of stone cell’s morphologicaland measured the stone cell’s diameter. The results showed that: the stone cell was prosperous in theparts of core and peel. In the initial stage, the central of pulp containing a group of stone cells from5to10, the structure was compact. By the proceeding of growth ang development, the stone cell began tolignification, and the size increased. The pulp cell around the stone cell increased at the form ofelliptical growing. In the midanaphase of growth and development, the group of stone cell graduallydisintegrated, the volume became smaller. The pulp cell increased until maturation stage. In maturationstage, the group of stone cell continued to disintegrate, the thickness of pulp cell wall decreased.