Plant growth promoting microorganisms in micropropagation

Micropropagation is a technique of producing new plants from single cell, tissue or small pieces of vegetative material. Micropropagation may be used in herbaceous plants such as strawberry, gladiolus and woody plants like apple, rose etc. Trichoderma harzianum inoculation in pomegranate cuttings resulted in significant increase in the number and length of primary roots (Satish Kumar, et al., 2001). Azospirillum lipoferum inoculated to cuttings of one year old runner shoots of pepper had increased root formation, root development, root weight and germination of cuttings (Govindan and Chandy 1985). Inoculation of Arbuscular mycorrhizal fungi in the cashew cuttings increased the plant height, stem girth and total biomass (Lakshmipathy, et al., 2000). Arbuscular mycorrhizal fungi increased the uptake of P, N, Mg, Cu, Fe, and Zn etc. in the micropropagated grape vine plants (Hare Krishna, et al., 2006). Application of Glomus fasciculatum in the micropropagated sugar cane plants increased the root biomass, improved survival rate, significant increase in percent colonization, sugar content, cane height and cane yield (Guleri, et al., 2005). Plant growth promoting microorganisms have the potential to contribute significantly to the development of sustainable agricultural system. Cost of chemical growth regulators and hazardous effects on cuttings can be eliminated to a greater extent with the aid of plant growth promoting microorganisms.