Effect of Plant Growth Regulators on Growth and Flowering of Gladiolus CV. Friendship

Abstract

A field experiment was conducted to study the effects of GA₃ (50 and 100 ppm), CCC (250 and 500 ppm), TIBA (150 and 300 ppm), and NAA (100 and 200 ppm) on the growth and flowering of gladiolus using a completely randomized design. The growth regulators were applied twice, first at six weeks and again at eight weeks after planting. Application of GA₃ at 100 ppm significantly increased plant height and leaf area. GA₃ at 100 ppm also resulted in the earliest flowering, by nearly 10 days, and reduced the total crop duration by 12.8 days. GA₃ at 50 ppm produced the longest spike and rachis and the maximum number of florets per spike. A significant increase in floret diameter was observed with GA₃ at 100 ppm, whereas the various growth regulator treatments did not significantly influence spike length.