Thermal Control Suitable for Increasing Petals in <i>Eustoma grandiflorum</i> (Raf.) Shinn.

Abstract

The number of petals in a flower is one of the most important appearance qualities of ornamental flowers. In Eustoma, the number of petals fluctuates significantly and little is known about how it is controlled. We investigated the cultivating conditions that affect the number of petals in double flowers and tried to develop a technique for growing splendid corolla. High temperature in the reproductive phase reduces the number of petals. The transient treatment of high temperature just prior to the petal initiation stage is sufficient to control such a reduction. The measurement of flower bud growth showed that one week of temperature treatment is necessary to control the number of petals in a flower. The integration of our results demonstrated that both daytime and nighttime temperatures affected the number of petals and that the number of petals was clearly correlated with average daily temperature within the range of 20°C < x < 25°C. This phenomenon applies to various cultivars in Eustoma grandiflorum. We propose the greenhouse conditions necessary to achieve both high quality flowers and reduced energy consumption by considering the temperature and stages of flower development.

Determining the Relationship between Floral Initiation and Source–Sink Dynamics of Tomato Seedlings Affected by Changes in Shading and Nutrients

“…In most studies, the floral initiation was described by the accumulated time or thermal effectiveness, which was used to predict the change of floral development from external stimuli (Brøndum and Heins, 1993). There was no distinction in the accumulation of photosynthesis production and morphological change in leaves (Kawakatsu et al, 2017;Luo et al, 2018;Tomer et al, 2018). In contrast, out results suggest a new direction in explaining the effect of external stimuli to floral initiation and provide a feasible way for controlling the floral imitation by using photosynthesis production (dry matter) or source organs (leaf area).…”

The effect of the drug Zircon on the decorative qualities of large-flowered eustoma plants in pot

“…The determination of the leaf area is of fundamental significance, since the leaves are directly related to processes such as evapotranspiration, radiation capture and CO2 fixation [9,10].…”

“…Currently, valuable eustoms varieties have been created for decorative and economic characteristics. Breeders have always sought to obtain plants with strong branches, simple and double inflorescences of various colors, as well as varieties resistant to wind, rain and fusarium -the main disease of eustoma [5,9,13].…”

“…In recent decades, numerous physiologically active substances (FAV) have been widely used in the practice of floriculture for open and protected soils as growth stimulators, which are used to increase the ornamental plants' biometric indicators, the effects on flowering time, plant resistance to extreme environmental conditions [6,9,12,14]. One of the most commonly used growth stimulants (active substances (DV) isolated from vegetable raw materials Ehinacea purpurea L. is the drug Zircon (DV is a mixture of hydroxycinnamic acids (PCC)).…”