The quality index - a new tool for integrating quantitative measurements to assess quality of young floriculture plants.

摘要

Floriculture crops are an important sector of ornamental horticulture, with an estimated wholesale value in the United States (U.S.) of US$ 4.13 billion in 2010. Furthermore, the value of propagative materials for these crops is US$ 376 million. The majority of floriculture crop producers utilize young plants including seedlings (plugs) or rooted stem-tip cuttings (liners) produced by propagation specialists and shipped to producers for finishing. Research has focused on improving the efficiency and quality of young plants production, since the advent of the "plug revolution" and increasing popularity of annuals produced from stem-tip cuttings has provided many challenges and opportunities in young plant production. Numerous quantitative measurements of seedlings and rooted cuttings are taken to measure the effects of environmental and/or cultural treatments during propagation. However, of greater importance to young plant producers is the cumulative effect of quantitative para-meters on young plant quality. To resolve this, a subjective rating based on perceived visual quality is sometimes used. Here we present the Quality Index (QI), a tool integrating several quantitative measurements and indices to provide an objective assessment of young plant quality. For example, we found that when the daily light integral is increased during propagation of seeds and cuttings of new and current floriculture crops, the QI of young plants increased by up to 858%. We will introduce this concept and discuss the applications, opportunities, and limitations of using the QI for assessing the effects of environmental and/or cultural conditions during propagation of young plant quality in floriculture production.