Effects Of Anti-cracking Agents On Fruit Qualities And Anatomical Structure Of Huizao

Jujube(Z. Jujuba Mill.) is a kind of rhamnaceae belong to Zizyphus Mill;since ancient times, it has been one of “five fruits”(peach, plum, plum, apricot,jujube). As a thermophilic, photophilous, drought-enduring and adaptable economicfruit species, jujube is viewed as the “iron crops”. Jujube is the preferred species towindbreak and sand-fixation, environmental greening, developing water-savingforestry and fruit growing. Huizao (its alias is Dazao) originated in Xinzheng; as theimportant local cultivation variety, it has excellent fruit qualities and is suitable forfresh, dried and processed. However, due to the presence of issues such as maturity inthe rainy season, neglect of management, unreasonable cultivation measures andspecial weather factors of the Yellow River Basin, fruit cracking is widespread,occurring almost every year, consequently, the phenomenon of high production butlow harvest appear generally.Huizao (susceptible) was sprayed8kinds of anti-cracking agents that have beenused to other fruit trees. They were Borax（PS）, Yinkerui（YR）, Ruiengai（RG）,Calcium Chloride（LG）, Calcium Nitrate（XG）,‘White Flour’(common name)（BM）, Duoxiaozuo（DX）, Naphthalene Acetic Acid(NAA)（NS）. This experimentstudied effects of different agents on fruit cracking rate, fruit qualities, mineralelements content and anatomical structure of Huizao. It aimed exploring theanti-cracking mechanism of Huizao, screening the agents which were effectiveagainst cracking but had no influence on fruit qualities, and providing certaintechnical support for effective cracking control in production. The main results are asfollows:1. In terms of fruit cracking rate, the effects of Yinkerui（YR）, Calcium Nitrate（XG）,‘White Flour（’BM）and Duoxiaozuo（DX）are better in different treatments.Compared with the control, in addition to the lower soluble sugar content andsignificantly higher titratable acid of NAA, other treatments have no significantinfluence on fruit weight, soluble sugar content, titratable acid, soluble solids contentof Huizao.2. The effects of differents agents containing Ca on the mineral elements contentof fruit peel and pulp are more obvious. Among them, the effects of Yinkerui（YR） and Calcium Nitrate（XG）on N, Ca, Mg content are better, which is beneficial tofruit cracking prevention of Huizao and may be associated with the presence form ofCa.3. The higher content of N, P, K in fruit pulp promote the occurrence of fruitcracking. Due to the significantly positive correlation between P content in the pulpduring the maturation period and fruit cracking rate, the P fertilizer applicationshould be controlled at the later growth stage. The correlations of Ca with Mg arealways extremely significantly positive at different stages; however, the correlationsof Ca with B never reached significant level.4. The epidermal of Huizao is thicker than that of Jixinzao, while the cuticle ofJixinzao is thicker than that of Huizao. Duoxiaozuo（DX）significantly increased theepidermal thickness of Huizao and epidermal\cuticle thickness of Jixinzao. Inaddition, fruit cracking is related to the arrangement of epidermal cell, the integrityand uniformity of cuticle and so on.5. The correlation between epidermal thickness of Huizao and Jixinzao is higherthan the correlation between cuticle thickness, indicating that jujube varieties have agreater impact on cuticle thickness. The correlation between epidermal thickness andcuticle thickness of Huizao and the correlation between epidermal thickness andcuticle thickness of Jixinzao are both higher, indicating that jujube varieties have noimpact on the correlation of epidermal thickness with cuticle thickness.