热水处理防治甘蔗宿根矮化病的效果及对再生植株影响研究*

 甘蔗宿根矮化病（Ratoon Stunting Disease,RSD）在我国蔗区普遍发生,研究其防治方法十分必要。应用50 ℃ 2 h热水处理严重感染RSD的粤糖00-236,新台糖22号种茎,用斑点酶标记免疫试验（Dot blot enzyme immunoassays,DB-EIA）检测RSD病原菌（Leifsonia xyli subsp. xyli,Lxx）,研究热水处理脱菌效果;并以粤糖00-236热水处理种茎与未处理种茎进行田间对比试验,研究热水处理对种茎再生植株的影响。结果表明:50 ℃ 2 h热水处理种茎可极显著的杀死感病种茎中的RSD病原细菌Lxx,对RSD有较好的防效,但不能彻底去除感病种茎中的Lxx。与未经热水处理种茎再生植株相比,经热水处理的粤糖00-236感病种茎再生植株的茎长、节间长度、一茎重显著增加,有效茎数极显著增多,生长速度加快,蔗茎产量增加23.2%,但成熟期甘蔗品质几乎无差异。另外,热水处理对种茎蔗芽有损伤,降低了种茎萌芽率。结果表明:50 ℃ 2 h热水处理甘蔗种茎能有效的防治甘蔗RSD,促进甘蔗生长,具有显著的增产效应。

Studies on Control Effect of Hot Water Treatment on Sugarcane Ratoon Stunting Disease by and Its Influence on Regenerative Plants

Since sugarcane ratoon stunting disease (RSD) has caused a lot of serious damage in China, It is very necessary to study the control method of RSD. Using RSD-infected seedcanes of 2 sugarcane varieties, YT00-236 and ROC22, as materials, the control effect of hot water treatment (HWT) at 50 ℃ for 2 hours on RSD was studied, combined with dot blot enzyme immunoassays (DB-EIA) to detect causal bacterium of RSD, Leifsonia xyli subsp. Xyli (Lxx). Meanwhile, comparative planting experiment between the YT00-236 seedcanes with HWT and its diseased seedcanes without HWT in the field was conducted to reveal the influence of HWT on regenerative plants. The results showed that HWT at 50 ℃ for 2 hours could extremely significantly reduce the population of Lxx in RSD-infected seedcanes, but complete elimination of Lxx was very difficult. The stalk length, internodal length and stalk weight significantly increased, the number of millable stalks per plot raised extremely significantly, the growth speed accelerated and the yield increased by 23.2%, respectively, of regenerative plants from the seedcanes with HWT, compared with those of RSD-infected seedcanes without HWT, but their qualities in maturity phase were similar. In addition, HWT could slightly injure cane buds and reduce germination rate of buds. It was concluded that HWT was an effective method of control of RSD, could promote plant growth and significantly increase cane yield.