不同基质对香蕉幼苗根系生长分析动态研究

孙寅虎 李芹 张光勇 刘学敏 杨绍琼 邓成菊 高梅 陈伟强 李伟 杜浩 李宗锴

摘 要 以椰糠、混合基质（体积比珍珠岩∶泥炭=4∶1）、复合生物菌剂、红壤土为基质，对‘红研一号香蕉组培苗进行营养杯栽培试验。通过测定和分析幼苗的生长状况及根系形成的动态影响，筛选出最适合的栽培基质。试验结果表明：混合基质栽培的香蕉幼苗在叶片数、叶片宽、叶面积、假茎粗、假茎高方面都有明显优势，对比其他栽培基质处理可缩短7 d左右的育苗时间。第35 d后，香蕉组培苗的生长状况均表现为混合基质>椰糠>红壤土>复合生物菌剂；在根系形成影响的过程中，第7 d后，混合基质和椰糠在根系长度、表面积、体积方面一直优于对照；但在21 d后，复合生物菌剂培养的香蕉幼苗的根系长度、表面积、体积等出现快速增长，由此表明，复合生物菌剂对根系的促进生长作用十分明显；35 d后，香蕉幼苗的根系形态总体表现为复合生物菌剂>混合基质>椰糠>红壤土。综合幼苗生长状况及根系形成的动态影响结果表明，混合基质更适合培育优质、健壮的无菌香蕉种苗，可广泛应用。

关键词 香蕉幼苗 ；基质 ；生长状况 ；根系形成

中图分类号 S668 文献标识码 A Doi：10.12008/j.issn.1009-2196.2018.02.001

Abstract Banana variety Hongyan 1 was tissue cultured and its plantlets were cultured in containers with different substrates， i.e. coconut coir dust， perlite/peat mixture （perlite∶peat = 4∶1）， complex microbial agents， or red loam， to determine and analyze their growth and the dynamic effects of different substrates on root formation for screening of the most suitable culture substrate. The results showed that the leaf number， leaf width， leaf area， and thickness and height of pseudostems of the banana plantlets were significantly higher in the treatment with the perlite/peat mixture than in the treatment with other substrates， and that the time for raising plantlets on the perlite/peat mixture was shortened by about 7 days as compared to the other treatments. After 35 days of container culture， the banana plantlets grew well on the substrates in the order of perlite/peat mixture > coconut bran > red soil > complex microbial agents. The perlite/peat mixture and the coconut coir dust were better in root formation with higher length， surface area and volume of the roots than the control after 7 d of culture， but after 21 days of culture the banana plantlets cultured on the complex microbial agents showed fast root growth in length， surface area and volume， which indicated an obvious effect of the complex microbial agents on the growth of root system. After 35 days of culture， the banana plantlets treated was better in root morphology in the order of the complex microbial agents > the perlite/peat mixture > the coconut coir dust > the red soil. Considering the plantlet growth and root formation it is concluded that the perlite/peat mixture is more suitable for the culture of high quality and robust disease-free banana plantlets which can be spread for wide use.

Keywords banana plantlet ； substrate ； growth ； root formation

在香蕉产业的发展中，香蕉二级苗的质量问题直接关乎香蕉是否优质和高产。香蕉是云南省红河州面积、产量最大，涉及面较广的主导产业[1]。目前，红河州香蕉育苗主要为土壤育苗，但是大量挖掘土壤，不僅会造成土壤的流失，而且土壤中难免会携带病虫害，对香蕉组培苗生长不利，尤其是枯萎病和线虫，一但感染后移栽大田，对香蕉生长极其不利[2-3]。因此，寻找一……