GB2092428A

GB2092428A - Method for separation of germinated seed from non-germinated seed

Info

Publication number: GB2092428A
Application number: GB8102650A
Authority: GB
Original assignee: VESTERGAARD LIS
Current assignee: VESTERGAARD LIS
Priority date: 1981-01-29
Filing date: 1981-01-29
Publication date: 1982-08-18

Abstract

Seeds are coloured black before germination and then germinated, whereupon the germinated seeds or the non-germinated seeds are sorted out by measuring the reflection of the individual seed. Non-germinated seeds will not reflect any light because of the dull black colour, while germinated seeds, usually having white germs, especially if they are germinated in dark, will reflect enough light to form the basis for a separation. The reflection measurement may be made with a photocell and a light source in a measuring chamber.

Description

SPECIFICATION Method for separation of germinated seed from non-germinated seed As wages, energy prices, investment costs, running costs, material costs, and seed prices are rising it is desirable to find a method that makes it possible to sow only germinated seed. That should make certain that every sowed seed becomes a perfect plant.

As there is no seed lot that will germinate 100 percent it is necessary to make a sorting. By present methods, however, that are exclusively manual the sorting must take place when the plant has grown so big that it can be handled. This implies that the above costs will rise as the germination procent is falling.

By conventional germinating methods it is impossible to make all able seed germinate, just as diseases from ungerminated seed may contaminate germinated seed. It may also be necessary to sow double to prevent bare spots because of ungerminated seed, and finally, the finished plant may be of an inferior quality because the small plants have been growing too close or too far from each other.

Because of this a lot of researce has been going on to find suitable methods to separate the seed after germination but before sowing.

Methods such as: Colouring of active biomass with indicator.

Separation by means of specific gravity.

Measuring of electric conductivity.

Measuring of temperature.

X-rays photographing.

Scanning by ultra-voilet light.

All these methods either damage the seed or they are too costly or impossible to use practically when having to separate millions of seed that vary greatly in size.

If you want to germinate the seed lot it is often necessary first to activate the seed and break down the germination controlling substances. This is done by submitting the seed to either a high or a low temperature.

Other means such as hormon treatment, stratification, or treatment with oxygen will start the seed germinating processes.

These treatments often demand a lot of space because it is necessary first to place the seed in a container or in a growth substrate, and often it is not practical to do at all.

If the seed, however, is sowed after germination all these treatments can be done in a narrow space, e.g. 1 litre of onion seed will consist of 1,000,000 single seed.

Today it is possible to treat and sow germinated seed. But it has so far not been possible to separate the germinated seed from the not-germinated seed.

This invention is a method that solves this problem easily, cheaply, and effectively.

Further, a machinery to carry out the invention is described.

All the small sprouts are completely white if the seed germinate in complete darkness, and a white seed sprout can be measured by a simple reflection measurement technique, i.e. a reflection indicates a germinated seed, and no reflection indicates a non-germinated seed.

Unfortunately only very few seed have totally black seed capsules from Nature's side. Most are more or less light in colour, and this will influence the measurements and make it impossible to get a reliable result, especially as there is always a great internal variation in the seed size of the same seed lot. The invention is therefor to colour the seed black in orderto obtain the maximum contrast when measuring.

It is possible to colour both dry and moist seed before they germinate.

The colour can be a stain that penetrates the outer part of the seed capsule, or a regular paint put on the outside of the seed capusle. It must be common for these materials that the pigment is black, easily handled, and not toxic to the seed.

Experiments have shown that by this method very small seed sprouts can be measured. The difference between the seed and the sprouts may be as small as 10 percent in order to obtain an effective separation.

The measurements can be made according to two principies: 1) The black coloured and germinated seed are dried so much that they just can be handled without sticking together. They can then be separated by means of the above reflection measurement, whereupon they have to be put back into water immediately. The separation has to be done in surroundings with a high relative humidity and the seed have only a short lifetime in dry condition depending of the size of the seed; e.g. letice seed about 20 minutes, leek seed about 30 minutes, bigger seed up to one hour, smaller seed 10 minutes or less.

2) The coloured and germinated seed are placed in water so that the measurement can be done from below through the water to avoid reflection from the water surface.

Suggestion for an apparatus to separate the coloured and germinated seed.

The apparatus can be divided into the following units: Separator.

Measuring chamber either stationary or for flow measurements.

Measurement head with and without optic.

Sorting mechanism.

Light source.

Electronic.

1. Dried Seed 2. Wet Seed Separator: 1. The dried seed is separated by means of a vibration channel that delivers the seed to the measuring chamber.

2. The wet seed is picked up from a waterfilled container by means of a vacuum nozzle that delivers it to the measuring chamber.

Measuring chamber: Equal for 1 and 2.

a) stationary measuring chamber can consist of a black surface either flat, round, or of a hemispherical plate or ball, upon which the seed is placed exactly above the measurement head.

b) flow chamber can consist of a black vertical or almost vertical tube or channel, upon which the seed slides or falls past the measurement head placed in the bottom of the tube channel.

Measurement head: Equal for 1 and 2.

By bigger seed the measurement head is a transparent plate under which photocell and light source are placed. By smaller seed it is necessary to use an optic to project an enlarged picture of the seed down upon the photocell.

Sorting mechanism: Equal for 1 and 2.

Measuring chamber with photocell and light source can be tilted to one side or the other for germinated/ not germinated seed. Or a vacuum nozzle can be used to suck the not-germinated seed away from the measuring chamber. Instead of a vacuum nozzle a pressure nozzle can be used with the same effect.

The germinated seed will then be kept, while the not-germinated seed will be led away for later disposal.

Light source: Equal for 1 and 2.

The light source can be either a powerful wolfram lamp or a quartz iodine lamp, if necessary with an optic to focus the light, and a glass fibre optic to lead the light to a place beside the photocell. It is very important that there is no direct or indirect light coming to the photocell.

Electronic: Equal for 1 and 2.

The electronics can consist of a photocell or a light sensitive transistor, e.g. a Darlington transistor which is both very sensitive and very fast. The delivered signal is amplified, and activates by means of a relay the sorting mechanism.

CLAIMS (Filed 29 Jan 1982) 1. Method for separation of germinated seed from non-germinated seed, characterized in that the seeds before being brought to germinate are coloured black, after which the germinated seeds are separated from the non-germinated by means of a reflection measurement.

2. Method according to claim 1, characterized in that the seeds are brought to germinate in the dark.

3. Method according to claim 1 or 2, characterized in that the reflection measurement is done in a measuring chamber, which comprises a light source and a device for measuring reflected light.

4. Method according to claims 1-3, characterized in that the seeds are coloured with dull black mordant or paint.

5. Method according to claims 1-4, characterized in that the separation is made without the seed being dried so much as to die.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. Measuring chamber: Equal for 1 and 2. a) stationary measuring chamber can consist of a black surface either flat, round, or of a hemispherical plate or ball, upon which the seed is placed exactly above the measurement head. b) flow chamber can consist of a black vertical or almost vertical tube or channel, upon which the seed slides or falls past the measurement head placed in the bottom of the tube channel. Measurement head: Equal for 1 and 2. By bigger seed the measurement head is a transparent plate under which photocell and light source are placed. By smaller seed it is necessary to use an optic to project an enlarged picture of the seed down upon the photocell. Sorting mechanism: Equal for 1 and 2. Measuring chamber with photocell and light source can be tilted to one side or the other for germinated/ not germinated seed. Or a vacuum nozzle can be used to suck the not-germinated seed away from the measuring chamber. Instead of a vacuum nozzle a pressure nozzle can be used with the same effect. The germinated seed will then be kept, while the not-germinated seed will be led away for later disposal. Light source: Equal for 1 and 2. The light source can be either a powerful wolfram lamp or a quartz iodine lamp, if necessary with an optic to focus the light, and a glass fibre optic to lead the light to a place beside the photocell. It is very important that there is no direct or indirect light coming to the photocell. Electronic: Equal for 1 and 2. The electronics can consist of a photocell or a light sensitive transistor, e.g. a Darlington transistor which is both very sensitive and very fast. The delivered signal is amplified, and activates by means of a relay the sorting mechanism. CLAIMS (Filed 29 Jan 1982)

1. Method for separation of germinated seed from non-germinated seed, characterized in that the seeds before being brought to germinate are coloured black, after which the germinated seeds are separated from the non-germinated by means of a reflection measurement.