اثر تيمارهاي پس از برداشت كلسيم بر پوست فرورفتگي ميوه ليموي (Citrus limon l Burm) ليسيون در دماي سرمازدگي يك بررسي بافت شناسي

Effect of postharvest calcium treatments on peel pitting of Lisbon Lemon (Citrus limon (L.) Burrn.) fruit at chilling temperature: A histological study

To reduce postharvest chilling injury and histological evaluation of chilling and resistance, Lisbon lemons were treated with CaCI2 solutions up to 7.5% (WN) by dipping (15 ʹc, 25 rnin.) or vacuum infiltrati on (15 ʹc, -33 kPa, 10 rnin.) before storage at 1.5 ·c and 85-90 % RHfor 6 and 12 weeks and I additional week at 20 ʹc. After 12 weeks storage, dipping in 3% CaCI2 and vacuum intiltration with 1.5% CaC~ were the most effeetive treatments and reduced the severity of pitting by 58.9 and 53.2 %, respectively. Pitting was manifested by parenchyma flattening and collapse of epidermal and a variable numher of sub-epidermal cell layer s extending between oil glands. The first signs of cellular damage were associated with collapsed cells immediately above oil glands, and lateral release of oil gland contents possihly indicating that the injured cell layers originated from oil gland disruption. Epidermal, sub-epidermal and parenchyma cell wall s of Ca-rreated fruit s stained strongly following cold temperature stora ge, possibly an evidence for Ca entry into fruit. These results were consi stent with the role of calcium in cell-to-cell adhe sion and tissue coherence properties in plants.