李的裂果机制及防止措施

Cracking Mechanism of Prunus salicina and Related Preventions

研究李果皮组织细胞生长以及水分和可溶性固形物(TSS)与裂果发生的关系,对裂果发生的组织解剖特点进行了观察,探索了喷施硼砂溶液、氢氧化钙溶液以及搭建塑料大棚等措施防止裂果发生的效果。研究结果如下:1.解剖学观察和显微测量表明,绥李3号果实开裂的直接原因为果实外皮层与内部薄壁组织细胞生长不协调所致。与吉林6号和绥棱红相比,绥李3号果实在快速生长期内部薄壁组织细胞生长速率显著过大(P<0·05),而表皮细胞生长缓慢或停止。加之其表面纹饰空隙较大容易形成潜在突破口,这样内外相互作用致使果实开裂。2.裂果的可溶性固形物含量显著高于正常果(P<0·05)。3.喷施硼砂可以减轻裂果,但喷施氢氧化钙溶液无明显效果。4.果实临近成熟时(8月初),土壤含水量与裂果程度呈正相关(P<0·05);搭建塑料大棚并在周围挖排水渠可以有效地减少绥李3号果实开裂,说明水分是影响绥李3号裂果的主要驱动因子。

Relationships among cell growth of fruit, water, or total soluble solid （TSS） with cracking of Prunus salicina L. were studied. Tissue anatomical characteristics of cracking fruit were observed. Effects of spraying borate or calcium hydroxide solutions and rain shield on trees for reducing cracking incidence were tested. The results were as follows： 1. Anatomical observations and micro-measurements showed that, uncoordinatedly growing between the outer dermal tissue of fruit and inner parenchyma caused fruit cracking. Compared with ‘Jilin 6＇ and ‘Suilinghong＇ , inner parenchyma cells of ‘Suili 3＇ grew significantly more faste during rapidly growing period （P 〈 0. 05 ） while epidermis grew slowly or stops developing. In addition, there exists bigger interspace of cutin decorations on surface of ‘Suili 3＇ , potentially becoming breakthrough point of cracking. In this way, combination of internal turgor forces caused by inner rapid growth acting on the fruit surface with the loss of skin elasticity caused fruit cracking. 2. TSS contents in cracking fruits are significantly higher than that of normal fruits （ P 〈 0. 05）, suggesting that higher TSS may easily induce fruit cracking. 3. ‘Suili 3＇ fruit cracking may be reduced through spraying of borate at 0. 5 mg/L. However, spraying calcium hydroxide solutions had no effect in reducing fruit cracking. 4. It is positive-correlated between soil moisture and the incidence of the cracking （ P 〈 0. 05 ） in August when fruits of ‘Suili 3＇ was nearly mature ; plastic rain shield and ditches may effectively reduce fruit cracking of ‘Suili 3 ＇ , suggesting that water is a driving factor that caused fruit cracking.