An Effective Embryogenesis Procedure from Anther Culture in Loquat

The objective of this study was to establish a highly effective embryogenesis procedure in anther culture of loquat (Eriobotrya japonica Lindl. 'Dawuxing'). The results showed correlations between diameters of flower bud and microspore developmental stages. When the transverse and vertical diameters of flower buds were 4.68 and 4.52 mm, respectively, microspores were at the late-uninucleate developmental stage, and were suitable for inducing embryos. Two days of cold treatment at 4 degrees C under darkness were more favorable than the control, resulting in 69.89% of callus formation. The most suitable medium for induction of callus from anthers was MS medium supplemented with 0.5 mg/L 2,4-D and 2.0 mg/L 6-BA, in which calli were induced at a frequency of 78.3%. The optimal induction of anther-derived embryos was achieved on MS medium supplemented with 0.05 mg/L ZT, 0.01 mg/L NAA and 0.05 mg/L IBA, in which the rate of embryo induction was 25.7%. The most suitable medium for anther-derived embryo proliferation was MS supplemented with 0.05 mg/L ZT, 0.02 mg/L NAA and 0.02 mg/L IBA, in which the proliferation coefficient was 5.8.