摘要
取１ｍｍ柑桔嫁接树茎尖在附加６－ＢＡ（１．０ｍｇ／Ｌ）和ＮＡＡ（０．４ｍｇ／Ｌ）的ＭＳ培养基上具有良好的分化效果；不同梢期的茎尖，其分化率不同。休眠结束后，刚开始萌发的芽或盛长期的芽最适合作茎尖培养的起始外植体。在以上分化培养基上，其茎尖萌发率可达７８．４％～８５．７％，且生长健壮；不同品种的柑桔茎尖在同一增殖培养基上，其增殖系数有较大差异；经连续继代增殖的芽转入改良的ＭＳ培养基中，进行壮苗培养，可获得健壮植株；采用１００ｍｇ·ｋｇ－１ＩＢＡ浸泡新梢基部，有利于生根。培养过程中，选择最适激素浓度，蔗糖浓度，培养基酸碱度以及足够的光照，可有效地避免试管苗黄化和玻璃状苗的出现。
The shoot tips about 1mm of grafted citrus tree underwent good differentiation on amodified MS medium supplied 6-BA(1.0 mg/L)and NAA(0.4 mg/L).The differentiation rate ofshoot tip varied with the different growing stages.The sproutings just affter the dormancy or atthe vigourous growth stages were most suitable to be the original explants for shoot tip cul-ture.The differentiation rate of shoot tip may reach 78.4%-85.7%and grow well on above moi-fied MS medium.The propagation rate also varied with the different varieties.Healthy plantletsmay be obtained from the continuously cultured buds growing on the modified MS medium.Soak-ing the base parts of newlydeveloped shoots with 100 mg·kg-1 IBA was favourable to root forma-tion.Optimum concentration of hormone and sucrose,suitable pH in culture medium and suffi-cient illumination could effectively control the occurance of yellowing and transparent plantlets in the culture tubes.
