套袋對黃冠梨果實中多糖和脂類分布的影響

摘 要： 以黃冠梨為試材，研究套袋果實生長發育過程中多糖和脂類的分布及其與花斑病發生的關系。結果表明，黃冠梨果實多糖主要分布表皮細胞層、單寧細胞層以及石細胞中，果肉的薄壁細胞中分布較少。隨著果實生長發育，果實中多糖逐漸增多，花后70 d染色最深，隨后又逐漸減少。果實中脂類主要分布在角質層、單寧細胞層和薄壁細胞，并隨果實發育，角質層和單寧細胞層變薄，但染色程度變化不明顯，而果肉的薄壁細胞染色越來越淺。套白袋和套3層袋的果實中多糖和脂類分布和變化與未套袋果實一致，但較未套袋果實染色淺，且3層袋果實染色最淺。套白袋和套3層袋果實的花斑病發生率分別為5.5％和22.5％，均高于未套袋果實。研究結果說明，套袋影響了果實發育過程中多糖和脂類的積累，這些物質含量的減少與果實花斑病的發生有密切的關系。

關鍵詞： 黃冠梨； 套袋； 多糖； 脂類

中圖分類號：Ｓ６６1．2 文獻標識碼：Ａ 文章編號：１００９－９９８０?穴２０11?雪０6－959－０5

Effect of bagging on distribution of polysaccharide and lipid in Huangguan pear fruit

WANG Ying-tao1，2， LI Xiao2， LI Yong2， LI Liu-lin1， ZHANG Shao-ling1*

（1College of Horticulture， Nanjing Agricultural University， Nanjing，Jiangsu 210095 China； 2Institute of Fruit Tree Research， Hebei Academy of Agriculture and Forestry Sciences， Shijiazhuang，Hebei 050061 China）

Abstract: Distribution of polysaccharide and lipid in fruit bagged with white one-layer and three-layer bag was observed， and its relationship with browning spot of Huangguan pear was explored as well. The results showed that: polysaccharide in fruit mainly distributed in epidermal cells， tannin layer and stone cells， and showed a little in parenchyma cell wall. The staining of polysaccharide in fruit gradually increased with fruit development， showed the heaviest at 70 days after full bloom， and then decreased. Lipid in fruit mainly distributed in cuticle， tannin layer and parenchyma cells. The cuticle and tannin layer thickness gradually became thin， but no obvious change on the staining of lipid in cuticle and tannins layer was observed during fruit development. The staining of lipid in parenchyma cell became light. The distribution and change trend of polysaccharide and lipid in bagged fruit were essentially consistent with those in non-bagged fruit， but the staining of polysaccharide and lipid in bagged fruit was much lighter than that of non-bagged fruit， and the staining of polysaccharide in fruit bagged with three layer bag was much lighter than that in fruit bagged with white one-layer bag from 80 days after full bloom. The rate of browning spot of fruit bagged in white one-layer and three-layer bag were 5.5% and 22.5% respectively， more than that of non bagged fruit. The data suggested that fruit bagging affected accumulation of polysaccharide and lipid， and there was close relationship between the decrease of polysaccharide and lipid and occurrence of browning spot.

Key words： Huangguan pear； Bagging； Polysaccharide； Lipid

黃冠梨具有外觀美、抗性強、結果早及連年豐產等諸多優良特性，深受廣大生產者及消費者的歡迎。套袋栽培能顯著提高果實的外觀品質[1]，已成為我國當前安全優質梨生產的主要技術手段。資料表明梨果實中含多糖，其積累程度對果實品質具有重要的影響[2]。然而，果實套袋后，由于改變了果實所處的微環境，進而影響到果實生長發育過程中多糖和脂類的分布，同時還發現套袋梨的果面易出現不規則的花斑，嚴重者花斑連成一片，俗稱“雞爪病”，從而導致果實品質的下降[3-4]。……