番茄果实组织在衰老和热胁迫中死亡率及DNA片段化的测定

组织、细胞死亡率及DNA片段化分析是番茄果实细胞程序性死亡(PCD)必不可少的检测指标。优化了番茄果实的电导率测定方法和TUNEL原位杂交方法,比较了不同甘露醇浓度和水作为介质对番茄果实圆片电导率测定的影响。0.2 mol/L~0.3mol/L的甘露醇溶液下番茄果实圆片的电导率较低,120 min后趋于稳定,而水为介质使番茄果实圆片电导率在测定的240 min内一直呈上升趋势,由30 min时的(23.95±0.85)%升至240 min的(63.95±0.35)%。结果表明0.3 mol/L甘露醇,震荡120 min为番茄果实电导率测定的适宜条件。进一步对成熟衰老和45℃热激处理的番茄果皮圆片电导率进行了测定,发现成熟的番茄及热激处理绿熟期果实细胞死亡率升高。对番茄果皮进行徒手切片的TUNEL原位荧光染色方法检测果实细胞DNA片段化简便可行,TUNEL原位杂交方法分别检测出了衰老果实和热激处理绿熟番茄果实TUNEL阳性细胞核。

Determination of Cell Viability and DNA Fragmentation in Tomato Fruit Induced by Senescence and Heat Stress

Cell viability and DNA fragmentation analysis are essential markers for tomato fruit programmed cell death(PCD).The ion leakage detection and TUNEL assay of tomato fruit method were optimized in this study,and compared the effect of different concentrations of mannitol and water as a medium on determination of ion leakage.The ion leakage of tomato fruit discs was lower in 0.2 mol/L(0.3mol/L of mannitol solution,and became stable after 120 min.But the ion leakage in water increased continually within 240 min...