Relationship Between Bitter Pit And Changes Of Ca、Mg、K Content, And Structure Of Vascular Bundle Of Stalks During Fruit Develepment

Apple is the most common fruit, sweet, crisp taste and rich nutrition is the world’s four major fruit crown, while Apple in fruit production in China occupies a dominant position.In recent years, with the popularization of bagging, the quality of apple and the occurrence of the disease are serious, which affect the quality, yield and storage of the fruit. Causal real Ca deficiency caused by physiological diseases, such as bitter pit disease, disease of chicken pox spots, watercore, cracking and postharvest fruit diseases, soften etc. caused by the poor quality of apple fruit, causing economic losses. Ca is not only essential nutrient for plant growth and development, but also as a signal material, many physiological and biochemical processes of plants are regulated. If the fruit Ca content is insufficient, often easy to cause a variety of physiological diseases seriously affect the product output, quality and farmer economic income. Therefore, resolving the shortage of Ca and the imbalance of mineral elements such as K and Mg is the main problem that need to be solved at present.This paper in ‘Dounan’ and’ Fuji’ apple varieties as experimental materials. Through the determination of fruit development during the fruit of different parts of water soluble Ca、Mg、K content and the change of the total quantity, fruit pedicle vascular bundle number and area and ‘Dounan’ onset fruit and normal fruit in different parts of water solution of Ca、Mg、K content and the total amount of the difference. To investigate the relationship between the occurrence of bitter pit apple and the fruit Ca、Mg、K and to provide the theoretical basis for taking appropriate measures to reduce the incidence of bitter pit. The main conclusions of the experiment are as follows:1. Water soluble Ca content o and the total Ca content between ‘Dounan’ and ‘Fuji’ in the fruit peel, fruit pulp, fruit heart during fruit development has a significant difference. The content of ‘Fuji’ is far higher than that of ‘Dounan’.2. In the process of fruit development, peduncle vascular bundle number and size is increasing, but in the same period ‘Fuji’ peduncle vascular bundle number and area are higher than the ‘Dounan’.3.The Ca contentin both lesion part and the rest in ‘Dounan’ with bitter pit is lower than the Ca contentin in the same part in ‘Dounan’normal fruit without bitter pit.4. ‘Dounan’ fruit with bitter pit have lower Ca content higher Mg, K content, lower Ca/Mg,and Ca/K compared with ‘Dounan’naomal fruit.