生长调节剂和基质对紫花苜蓿扦插繁殖效率的影响

Effects of different growth regulator treatments and culture mediums on clonal propagation of alfalfa

紫花苜蓿(Medicago sativa)作为异花授粉植物,其有性繁殖易受各种因素影响而失去原有的遗传完整性。扦插克隆作为一种无性繁殖手段,对苜蓿保优传代、快速获得制种群体和培育优良品种具有重要意义。本研究以苜蓿雄性不育突变体ms1为材料,探究不同浓度生长调节剂及不同栽培基质对苜蓿扦插繁殖效率的影响。结果表明,不同生长调节剂对苜蓿插穗再生性能的影响差异显著(P<0.05),其中生根粉(ABT)最好,萘乙酸(NAA)次之,吲哚丁酸(IBA)最差,且150mg.L-1 ABT处理插穗生根效果最佳,成活率达88.3%,比对照高71.0%,并具有较高的生根数(3.94条)、根长(8.96cm)、根系效果指数(0.75)和叶片数量(10.46枚)。不同栽培基质对苜蓿插穗成活率的影响差异不显著(P>0.05),但对插穗的生根数、根长、叶片数量和根系效果指数均存在显著影响(P<0.05),其中,混合基质优于单一基质,以M4(园土+蛭石+珍珠岩)和M5(园土+河沙+珍珠岩)诱导再生效果最好,而单一园土的扦插繁殖效果最差。

Alfalfa （Medicago sativa ） is a typical perennial autotetraploid and outcrossing plant. The sexual reproduction of alfalfa is susceptible various factors, and its original genetic integrity is easy to lose. Vege- tative propagation of alfalfa by stem cutting is extremly important to ensure the genetic stability of alfalfa resources and cultivars. In this research, taking male sterile mutant （rnsl） identified in alfalfa as experi- mental material, the effects of different growth regulator treatments and culture mediums on its clonal propagation were studied. The results showed that, there were significant differences among treatments of three growth regulators on the clonal propagation （P〈0.05）. The efficiency of ABT was the best for the regeneration, and then followed by NAA and IBA. The highest rooting rate reached under treatment of 150 mg· L-1 ABT. Under this treatment, the survival rate was up to 88.3%, which was 71.0G higher than that of the control （P^0.05）, and also exhibited the good performance of numbers of root （3.94）, root length （8.96 cm）, rooting effect（0.74） and numbers of leaf （10.46）. The survival rate of all the cut- tings was not significant different among the five culture mediums （P〈0.05）, while significant differences in the numbers of root, root length, rooting effect and numbers of leaf were found （P〈0.05）. The mixed culture medium was better than the single culture medium, which provided a good support for the growth of cloning plants, and the efficiency of M4 （soil ＋ vermiculite ＋ perlite） and M5 （soil ＋ sand ＋ perlite） were the best compared to the single garden soil.