Effect of different factors on in vitro shoot tip culture establishment in mango.

The individual effects of pre-treatment, explant size, explant age, explanting season, basal salt medium formulation and growth regulators were investigated on shoot in vitro culture establishment in monoembryonic mango cvs. Amrapali and Pusa Arunima. Endophytic microbial contamination and rapid browning of explant and culture medium were the major factors, which delimited the explant establishment. Regardless of genotype and duration, pre-treatment comprising etiolation + spray of imidazole + agitation in 0.2% PVP solution before culture was found best with regards to improved culture establishment and reduced infection of shoot cultures. The smaller explants exhibited higher medium browning compared to longer ones. The highest explant survival and least browning were recoded when 4.0 cm long explant were employed. Likewise, explants excised from older shoots, i.e. from 3 to 4-month-old current season shoots registered higher survival in comparison to one week or 3–4 week-old explants. Explants inoculated on medium comprising B5 macro-salts excluding (NH4)2SO4 and (NH4)2NO3 plus MS micro-salts and organics supplemented with 0.5 mg l−1 NAA plus 2.0 mg l−1 BAP in March were found superior over other combinations.