Effect of Scale Planting Depth and Fertilizer Application on Growth Responses of Parent Scale and Newly Formed Plantlet during Scale Propagation in the Easter Lily

Abstract

This work was designed to study the effect of scale planting depth and fertilizer application on growth responses of parent scale and newly formed plantlet during scale propagation in the Easter lily under outdoor conditions.
The dry weight to fresh weight ratio (D/F ratio) of the apical part of parent scale decreased more rapidly than that of the basal part. This tendency was more prominent on the light exposed scales or those fertilized than on those buried 3cm below the soil surface or those not fertilized, respectively.
A little after the decrease of parent scale D/F ratio, the foliated scale bulblet ratio and the dead scale ratio increased simultaneously on the light exposed scales, whereas on the buried scales the dead scale ratio increased very slowly as compared with the increase of foliated scale bulblet ratio.
No effect of fertilizer application was observed on the number of scale bulblets or the type of leaf development (plant type).
Stem roots developed more rapidly and the number of stem roots was greater when scales were buried than when they were light exposed.
Regardless of scale planting depth, number of foliage leaves on the shoots was greater on those fertilized than on those not fertilized.
The size of scale bulblet was a little greater on the light exposed scales than on the buried scales at the earlier stage of the plantlet growth. In May, however, it was greater on buried than on the light exposed scales.
No difference was observed between the D/F ratio of scale bulblet in bolted plantlets and those not bolted.
The scale bulblet D/F ratio became greater as the scale bulblet grew. It was generally greater on those not fertilized than on those fertilized.
The increase of scale bulblet D/F ratio during December to May was greatest on buried-fertilized scales.
Thus, the fertilizer application on the buried scales is thought to be desirable for the promotion of scale bulblet growth, for it produces much more foliage leaves and stem roots which are essential for bulblet growth.