薄壳山核桃愈伤组织诱导的优化

Optimization of Callus Induction in Pecan

本研究以薄壳山核桃品种苗‘波尼’幼嫩叶片为外植体,设置不同消毒方法、不同蔗糖浓度、不同褐化抑制剂及不同植物生长调节剂浓度及配比,研究其对叶片诱导愈伤组织形成的影响。结果表明,不同消毒方法对薄壳山核桃叶片愈伤组织形成影响显著,以0.1%HgCl2消毒2 min效果最好,污染率为15.6%,且愈伤组织生长状态最好;不同蔗糖浓度对叶片愈伤组织形成的影响以30 g/L效果好,愈伤诱导率达75.6%;不同褐化抑制剂对叶片愈伤组织影响较小,其中以0.2 g/L PVP效果最好,不仅褐化率低且愈伤诱导率高;不同植物生长调节剂浓度及配比对薄壳山核桃叶片愈伤组织形成影响显著,以4/5MS+0.75 mg/L TDZ+0.5 mg/L6-BA+0.5 mg/L NAA培养基与改良DKW+0.4 mg/L TDZ+0.4 mg/L IBA培养基诱导效果最好,研究发现低浓度的TDZ(0.2~0.4 mg/L)促进愈伤组织形成,高浓度的TDZ(0.8~2.0 mg/L)抑制愈伤组织形成。本研究可筛选出诱导叶片愈伤组织的最佳方法,为后期愈伤组织诱导不定芽提供科学依据。

The young leaves of the pecan seedlings’Pawnee’were used as explants,and different disinfectants and disinfection time,different sucrose concentrations,different browning inhibitors and different plant growth regulator concentrations and ratios were set,to study the effect of leaf-induced callus formation.The results showed that different disinfection methods had significant effects on callus formation of pecan leaves.The best effect was achieved by disinfecting with 0.1%HgCl2 for 2 min,the pollution rate was 15.6%,and the callus growth state was the best.The effects of different sucrose concentrations on leaf callus formation were better at 30 g/L,and the callus induction rate was 75.6%.Different browning inhibitors had less effect on leaf callus,among which 0.2 g/L PVP had the best effect,not only the browning rate was low,but also the callus induction rate was high.The concentration and ratio of different plant growth regulators had significant effects on the callus formation of pecan leaves,with 4/5 MS+0.75 mg/L TDZ+0.5 mg/L 6-BA+0.5 mg/L NAA medium.The improved DKW+0.4 mg/L TDZ+0.4 mg/L IBA medium had the best induction effect,and the low concentration of TDZ(0.2~0.4 mg/L)promoted callus formation,and the high concentration of TDZ(0.8~1.0 mg/L)inhibit callus formation.This study can screen out the best method for inducing leaf callus and lay a foundation for the induction of adventitious buds in later callus.