The effect of corm size and division of the mother corm in gladioli

Abstract

The effects of size and division of the mother corm on yield of gladioli inflorescences, corms and cormlets and on inflorescence quality were studied in two experiments in south-east Queensland. Planting with whole large corms resulted in greater inflorescence yield, higher inflorescence quality and gave more high quality inflorescences than planting with smaller corms. Flowering percentage [(number of inflorescences/number of corms planted) x 100] was increased by cutting the large corms, but was reduced by cutting the smaller corms. Inflorescence quality was reduced by cutting corms. Some multiple shooting (greater than one shoot per corm) occurred with whole large corms and increased the flowering percentage, but inflorescence quality was still higher than for the smaller corms, and was acceptable by market standards. The yield of new corms was increased by cutting corms of large or number 3 size, but was reduced by cutting the smaller initial corms. For the large corms, cutting increased the yield of new corms by 93%. The method of cutting corms influenced subsequent plant development. Cutting to remove storage tissue and damage to part of the root initials without damaging the buds, stimulated multiple shooting, increased inflorescence yield, decreased inflorescence quality, and substantially increased the number and weight of new corms. Removal of buds in cutting reduced inflorescence number and corm and cormlet yield. Commercial producers may be able to cut large corms to rapidly propagate new planting material, concurrently with flower production. However, cultivars differ in their response to cutting.