Micropropagation of 'Wild Pear' Pyrus pyrifolia (Burm F.) Nakai. I. Explant Establishment and Shoot Multiplication

Abstract

The study was undertaken to standardize in vitro explant establishment and shoot multiplication technique for wild pear. The highest explant establishment (77.88%) was observed during spring, which was on a par with explant establishment frequency during winter season (76.21%). The lowest explant establishment was observed during rainy season (61.94%). The establishment frequency for shoot tips (69.07%) was significantly less than the establishment frequency for nodal segments (71.95%). The antibrowning agents decreased explant browning, yet they could not eliminate it. The magnitude of the effect of the antibrowning agents depended on the season of explant collection and type of explant. Antibrowning agents were more useful during spring and winter seasons when the incidence of browning was low, in comparison to rainy, summer and autumn seasons when the browning was comparatively high. Though, the highest number of shoots (11.24/ culture) were obtained with 2.0 mg per litre BA, but this BA level did not produce shoots of desirable length (>2.0 cm). BA (1.5 mg per litre) + IBA (0.5 mg per litre) was the best growth regulator combination for shoot multiplication in wild pear as it produced sufficient number of shoots (10.21 shoots per culture) having desirable shoot length. The highest number of shoots per culture (11.20) was obtained with Woody Plant Medium (WPM), followed by MS medium (10.21). The highest shoot length (3.21 cm) was observed with MS Medium and it was on a par with WPM.

Keywords

• explant browning
• shoot multiplication
• micropropagation
• wild pear