Effect of various corm sizes on the vegetative, floral and corm yield attributes of gladiolus

Corm and cormel production of gladiolus has major role in the growth and development of gladiolus industry. However, its commercial cultivation is mainly limited by rare production of corms and cormels and thereby does not fulfill local demand of the countries. A field experiment was conducted to investigate the effect of corm size on the vegetative and floral attributes and corm and cormel production in gladiolus. The main objective of the present study was to find out the best corm size on the basis of both corm diameter and weight in order to standardize conventional method of propagation for producing more corms and cormels. For this purpose, corms of three commercially grown varieties viz. Traderhorn, White Friendship and Peter Pears of three different sizes- small, (dia. 2.2-2.4 cm), medium (dia. 2.7-3.0 cm) and large (dia. 3.2-3.5 cm) were planted in split plot design consecutively for two years, i.e., 2006 and 2007. Large sized corms s ignificantly increased the leaf breadth, length of flowering spike, and number of florets spike-1 over those produced from small and medium sized ones, whereas plant height was greatly decreased in response to large sized corms. Regarding corm production, large sized corms produced significantly higher weight of corms per plant, cormels per plant and combined total weight of corms and cormels plant in all the three varieties of gladiolus. However, variety wise Peter Pears got the best results. The yield of new corms per plant was significantly increased in response to large sized corms both in White Friendship and Peter Pears, whereas, Traderhorn had no effect of corm size for number of corms per plant. Cormel production also depicted significant results in response to large sized corms in all the three varieties of gladiolus. All obtained corms and cormels were graded on the basis of diameter into large as well as small sized corms when categorized according to the standards of North American Gladiolus Council.