Effect of growth regulators on growth, flowering and rhizome yield of ginger ( Zingiber officinate Rosc)

Field experiments were conducted in 2001 and 2002, to study the effect of foliar application of growth regulators on growth; flowering and rhizome yield of ginger ( Zingiber officinale Rosc .). Treatments consisted of gibberellic acid (GA3) at 0,150 and 300 ppm; ethrel at 0,100 and 200 ppm and cycocel (CCC) at 0,250 ppm and each concentration was applied in 5 sprays at 24 days interval starting from 8 weeks after planting. The experiment was a 3x3x3 factorial laid out in a randomized complete block design with 3 replications. Results showed that GA 3 inhibited flowering and shoot emergence while ethrel had no effect on flowering but enhanced shoot emergence. Leaf area (LA), leaf development rate (LDR), stem elongation rate (SER), vigour index (VI) and rhizome yield were increased with CCC and decreased with GA and ethrel. Application of CCC at 250 ppm significantly improved rhizome yield by 36.4%. Keywords : Ginger, growth regulators, growth indices, rhizome yield Nigerian Journal of Horticultural Science Vol. 9 2005: 69-73