TWI886088B - Method for cultivating onion seedling - Google Patents

Abstract

A method for cultivating onion seedling is used to cultivate less spicy edible bulbs. The method comprises: seeding an onion to obtain an onion seedling. When cultivating the onion, a light with a photosynthetic photon flux density (PPFD) of from 200 µmol m ^-2s ^-1to 300 µmol m ^-2s ^-1is used to irradiate the onion for 24 hours per day.

Description

Cultivation method of onion seedlings

The present invention relates to a method for cultivating onions, in particular to a method for cultivating onion seedlings.

Onion ( Allium cepa L.) is a biennial herb of the genus Allium, family Onionaceae. The edible part is the scales, which refers to the enlarged part at the base of the leaf sheath in the late growth stage. Generally speaking, it takes about a year to harvest the scales. However, during the onion cultivation process, an organic sulfur compound called diallyl disulfide (DADS) is formed in the scales, giving the scales a unique spicy taste, which has hindered the development of onion recipes.

In view of this, it is indeed necessary to provide a method for cultivating onions so as to cultivate edible scales with less pungent taste.

To solve the above problems, the main purpose of the present invention is to provide a method for cultivating onions for cultivating edible scales with less pungent taste.

The onion seedling cultivation method of the present invention may include: sowing an onion seed to obtain an onion seedling, wherein during the cultivation of the onion seed, the onion seed is irradiated with light having a photon flux density of 200 to 300 μmol m ^-2 s ^-1 for 24 hours per day.

In the onion seedling cultivation method of the present invention, after the onion seeds are sown, the onion seeds can be cultivated with water before the onion seeds germinate and grow the first leaf.

In the onion seedling cultivation method of the present invention, after the onion seeds germinate and grow the first leaf, and before the onion seedlings are obtained, the onion seeds can be cultivated in an onion anti-lean growth solution.

In the onion seedling cultivation method of the present invention, each liter of the onion anti-lean growth solution may contain: 26.6 mg of nitrate nitrogen, 9 mg of ammonium salt nitrogen, 23.81 mg of phosphorus, 79.91 mg of potassium, 19.17 mg of calcium, 0.02 mg of sulfur, 0.03 mg of zinc and 0.54 mg of boron.

Accordingly, by irradiating the onion seeds with light of a specific photon flux density for a specific period of time, the scales of the obtained onion seedlings can be made to swell earlier. In addition to accelerating the acquisition of edible scales, the shorter the cultivation time, the lower the content of diallyl disulfide in the scales, thereby reducing the pungent taste of the scales, which is the effect of the present invention.

In order to make the above and other purposes, features and advantages of the present invention more clearly understood, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings as follows:

The onion seedling cultivation method of the present invention may include: sowing an onion seed to obtain an onion seedling.

It is noteworthy that in the onion seedling cultivation method of the present invention, during the process of cultivating the onion seeds, the edible scales of the obtained onion seedlings can be rapidly expanded by using a specific light intensity, thereby obtaining onion seedlings containing onion scales with less pungent taste.

Specifically, workers can sow the onion seeds into a plug tray, and then place the plug tray in a step-in growth box, so that the walk-in growth box can intelligently adjust the environmental parameters such as temperature, carbon dioxide concentration and light required for the germination and growth of the onion seeds. In this embodiment, the environmental parameters of the walk-in growth box are set to: average day and night temperature 25/22°C, carbon dioxide concentration of 800 ppm, light quantity [photosynthetic photon flux density (PPFD)] of 200-300 µmol m ^-2 s ^-1 (full sunlight).

Furthermore, after sowing the onion seeds, until the onion seeds germinate and grow the first leaf (about 14 days), workers can cultivate the onion seeds with water (conductivity of 0.1 ms‧cm ^-1 ).

Then, the worker can further cultivate the onion seeds in an onion anti-lean growth solution (with a conductivity of 0.8 ms‧cm ^-1 ) after the onion seeds germinate and grow the first leaf and before the onion seedlings are obtained (about 31 days). In this embodiment, each liter of the onion anti-lean growth solution can contain: 26.6 mg of nitrate nitrogen (NO ₃ -N), 9 mg of ammonium salt nitrogen (NH ₄ -N), 23.81 mg of phosphorus, 79.91 mg of potassium, 19.17 mg of calcium, 0.02 mg of sulfur, 0.03 mg of zinc and 0.54 mg of boron.

45 days after sowing (DAS = 45), onion seedlings with early swollen bulbs can be harvested.

In order to verify that the onion seedling cultivation method of the present invention can be used to obtain onion seedlings with early swelling of scales, the daily light hours were adjusted to 12/12 (12 hours of sunshine and 12 hours of darkness), 16/8 (16 hours of sunshine and 8 hours of darkness) and 24/0 (24 hours of sunshine and 0 hours of darkness), and the other environmental parameters (such as average day and night temperature, carbon dioxide concentration, light quantity and culture solution) were all exactly the same.

45 days after sowing, the growth of onion seedlings in each group was analyzed. The results are shown in Table 1 and Figure 1. In the group with 24 hours of light per day, the scales swelled prematurely.

Table 1 Group Plant height (cm) Fresh weight (g) Dry weight (g) Root length (cm) Number of leaves (n) Stem diameter (mm) 12/12 27.5±4.8 ^ab 0.60±0.031 ^a 0.134±0.026 ^b 12.5±6.0 ^a 3.0± ^0.0a 4.73±1.01 ^b 16/8 23.6±2.6 ^bc 1.59±0.297 ^a 0.127±0.020 ^b 10.9±3.7 ^a 2.8±0.4 ^ab 4.62±0.22 ^b 24/0 20.7±1.8 ^c 1.37±0.303 ^a 0.175±0.025 ^a 7.9± ^1.0a 2.4±0.5 ^b 9.63±0.66 ^a

In summary, by irradiating the onion seeds with light of a specific photon flux density for a specific period of time, the scales of the obtained onion seedlings can be made to swell early. In addition to accelerating the acquisition of edible scales, due to the shorter cultivation time, the cumulative amount of diallyl disulfide in the scales is lower than that of onions whose scales do not swell early (normal onions), thereby reducing the pungent taste of the scales, which is the effect of the present invention.

Although the present invention has been disclosed using the above preferred embodiments, they are not intended to limit the present invention. Any person skilled in the art may make various changes and modifications to the above embodiments without departing from the spirit and scope of the present invention, and the scope of protection of the present invention shall be subject to the scope of the attached patent application.

without

[Figure 1]     Photos of the onion seedlings in each group of this experiment.

Claims (4)

A method for cultivating onion seedlings comprises: sowing an onion seed to obtain an onion seedling, wherein during the cultivation of the onion seed, the onion seed is irradiated with light having a photon flux density of 200 to 300 µmol m ^-2 s ^-1 for 24 hours per day. The method for cultivating onion seedlings of claim 1, wherein the onion seeds are cultivated in water after sowing and before the onion seeds germinate and grow the first true leaf. The method for cultivating onion seedlings of claim 2, wherein the onion seeds are cultivated in an onion anti-lean growth solution after the onion seeds germinate and grow the first leaf and before the onion seedlings are obtained. The method for cultivating onion seedlings of claim 3, wherein each liter of the onion anti-lean growth solution contains: 26.6 mg of nitrate nitrogen, 9 mg of ammonium salt nitrogen, 23.81 mg of phosphorus, 79.91 mg of potassium, 19.17 mg of calcium, 0.02 mg of sulfur, 0.03 mg of zinc and 0.54 mg of boron.