不同热处理对甘蔗蔗茎脱毒效果的影响

Effects of different treatments on efficiency of virus-free seed-stems of sugarcane

为确定甘蔗脱毒的最佳方式,以期为甘蔗脱毒健康种苗的生产提供一条切实可行的途径,将甘蔗蔗茎分别置于不同温度的恒温水浴中进行不同时间的恒温热处理。结果表明:不同热处理对蔗茎处理7 d后,低于52℃的各处理萌芽率均在90%以上,52℃处理30 min以内萌芽率均为60%以上,其余处理蔗茎萌芽率低于30%;当热处理温度高于55℃、58℃和61℃时可以分别获得脱去宿根矮化病(RSD)、花叶病毒(Sc MV)和黄叶病毒(Sc YLV)的腋芽,但是蔗茎萌芽率低于20%;而在52℃恒温热处理30 min后经过38℃恒温气候箱中培养1周后,蔗芽生长点均未检测出以上3种病原微生物。以此最佳条件,研究了心叶诱导愈伤组织培养、腋芽培养、温水处理种植和恒温热处理结合腋芽分生组织培养4种脱毒方式的脱毒效果,发现心叶诱导愈伤组织培养和恒温热处理结合腋芽分生组织培养脱毒效果最佳,但是继代培养过程中发现,经诱导愈伤组织培养产生的无性系后代中变异个体较多。因此,恒温热处理结合腋芽分生组织培养为甘蔗的最有效的脱毒途径,可以培养出脱毒健康种苗。

In order to find out the most efficient pattern to get virus-free sugarcane, and provide a viable way to produce healthy sugarcane seedlings. We put seed-stems of sugarcane into different thermostat water baths. The results revealed that the percentage of germination was higher than 90% when the temperature was lower than 52℃ after 7 days of different hot water baths, and was higher than 60% when the temperature was 52℃ and the time was 30 minutes, and was lower than 30% in other treatments. When the temperature was above 55℃, 58℃ and 61 ℃, we could get sprouts without ratoon stunting disease, sugarcane mosaic virus and sugarcane yellow leaf virus respectively, but percentage of germination was lower than 20%. However, if we put the seed-stems in 52~C thermostat water bath for 30 minutes then cultivated in 38℃ thermostat for one week, we cann＇ t detect pathogenic microorganisms in growing points of sugarcane. Then under the best condition, we compared the efficiencies of four virus-free ways： callus induced from heart leaves, axillary bud cultivated, putting into warm water before planting and hot water bath combined with meristems of axillary bud cultivated. The first and the forth method were better than others. However, after several times transfers of culture, there were more mutants when the callus induced from heart leaves. Thus, hot water bath combined with meristems of axillary bud cultivated was the best treatment, which could cultivate healthy sugarcane seedlings.