柑桔原生质体抗热性及自由基清除剂对其影响

山金柑（ＦｏｒｔｕｎｅｌａｈｉｎｄｓｉＯｓｄ．ｃｖｓｗｉｎｇｌｅ），伏令夏橙（ＣｉｔｒｕｓｓｉｎｅｎｓｉｓＯｓｂ．ｃｖｖａｌｅｎｃｉａ）和种间杂种Ｍｕｒｃｏｔ桔橙（Ｃ．ｒｅｔｉｃｕｌａｔａＢｌａｎｃｅⅹＣ．ＳｉｎｅｎｓｉｓＯｓｂ．ｃｖｍｕｒｃｏｔ）的胚性愈伤组织经酶法分离原生质体，测定原生质体在不同高温下的完整率和活性率。结果表明：耐热性不同的柑桔胚性愈伤组织原生体在细胞膜热稳定性上存在明显差异，山金柑（５２．４９℃）＞伏令夏橙（５０．４２℃）。由原生质体活性率的变化计算出的半致死温度（ＬＴ５０）可用于柑桔原生质体耐热力的测定。超氧化物歧化酶（ＳＯＤ）的拮抗剂二乙基二硫化氨基甲酸钠（ＤＤＣ）能显著降低柑桔原生质体的抗热性；自由基清除剂苯甲酸钠（ＳＢＮ）则显著提高了柑桔原生质体的抗热性；ＳＢＮ对耐热性弱的品种的保护效果高于对耐热性强品种的保护效果。

HEAT RESISTANCE OF CITRUS PROTOPLASTS AND PROTECTIVE EFFECTS OF RADICAL SCAVENGERS

There is a significant difference on heat stability of membrane between citrus embryogenic callus protoplasts with different heat tolerance. LT 50 obtained by combining protoplast viably percentage with Logistic equation could be used as the criterion of heat tolerance of protoplasts. DDC could decrease heat resistance of citrus protoplasts, whereas SBN had the opposite effect. The protective effect of SBN on low heat tolerance variety is better than on high heat tolerance one.