Regeneration of Pear (Pyrus communis L.) From Shoot Tip and Nodal Cultures

In vitro regeneration is a potential tool used for the preservation of superior germplasm and breeding of fruit species. Nodal segments and shoot tips were cultured in different concentrations and combinations of plant growth regulators (PGR) to evaluate the  in vitro regeneration  potential of pear (Pyrus communis L.) cv. Nashpati. Murashige and Skoog (MS) medium was used as basal medium combined with different concentrations and combinations of  NAA and IBA and TDZ. MCL (Cheveau and Leblay Regeneration Medium), CL vitamins, and SPSP (Cheveau and Skirvin Standard Pear Shoot proliferation Medium) was used in these investigations. MS medium (6899: 4.4g in 1000 ml of dd water) containing IBA and NAA were used for root initiation. Nodal segments and Shoot tips (1 cm) were excised and cultured onto nutrition medium. Cultures were incubated in a growth cabinet at 23 °C to 25 °C under 2500 lux inflorescent light intensity with a 16-h photoperiod. Nodal segments gave more shot initiation percentage (88%) in  Murashige and Skoog salts containing 2.0 (μM) TDZ  followed by MS + 0.5 (μM) NAA + 2.0 (μM) TDZ where 75% shoot initiation was achieved. Shoot tip explant gave 69 and 62 shoot initiation percentage respectively in both the cases.  The shoots initiated in first step were transferred to SPSP medium (Chvreau and Skirvin Standard Shoot Proliferation Medium) for shoot proliferation and elongation. Shoots obtained in second step were  transferred onto root induction medium i.e. MS + 0.1 (μM) NAA + 5.0 (μM) IBA and rooted shoots were transferred onto MS (6899: 1.7g) without plant growth regulators for root elongation. After two weeks the rooted plants were transferred to small earthen pots containing peat moss without nutrients and were placed in mist unit for acclimatization. Almost all of the plants were acclimatized and survived in field.