CPPU對尼羅草(Acroceras macrum Stapf)癒合組織誘導與植株再生之影響

Abstract

The objectives of the studies were to develop a system for callus induction and plant regeneration from immature inflorescences of nilegrass (Acroceras macrum Stapf cv. Taishu No. 1). Explants were cultured on an MS (Murashige and Skoog) medium supplemented with 2.00 mg L^(-1) 2,4-D (2,4-dichlorophenoxy acetic acid) and different concentrations of CPPU (N-(2-chloro-4-pyridyl)-N'-phenyl urea). The effects of CPPU on callus induction frequency were examined. The frequency of callus induction was 72.4% when immature inflorescences were cultured on MS medium with 2.00 mg L^(-1) 2,4-D and 0.10 mg L^(-1) CPPU for 5 weeks. For plant regeneration, the callus was transferred to MS medium with BA (N6-Benzyladenine) or TDZ (N-phenyl-N'-1, 2, 3-thiadiazol-5-lurea). The frequency of shoot regeneration was 16.7% with 0.05 mg L^(-1) TDZ and 13.3% with 1.0 mg L^(-1) BA. To increase the frequency of plant regeneration, callus induced with 2.00 mg L^(-1) 2,4-D and 0.1 mg L^(-1) CPPU was transferred to MS medium with 0.5 mg L^(-1) NAA and 1.0 mg L^(-1) TDZ for 5 weeks. This increased the shoot regeneration significantly by 77.8%. The shoots were transferred to 1/2 MS medium for rooting and then transplanted to the field. The percentage of surviving plantlets was more than 92%. From these results, we established an efficient system for plant regeneration from immature inflorescences of nilegrass. It would be helpful for commercial mass production of nilegrass propagation.