Knowledge of the principles and methods of determining seed viability by the fluorescence method.
Operation method
Fluorescence method to detect seed experiments
Principle
Plant seeds often exist in the ultraviolet irradiation can produce fluorescent substances, such as certain flavonoids, coumarins, phenolic substances, etc., in the seed aging process, the structure and composition of these fluorescent substances often change, and thus the fluorescence of the color is also a corresponding change in some of the seeds in the aging of the death of fluorescent substances in the nature of the nature of the fluorescent material has not changed, but due to the decline in viability or the death of the cells of the protoplasm of the increase in permeability. The fluorescent substance in the seed can easily seep out when the seed is dipped. In the former case, the seed viability can be determined by directly observing the fluorescence of the seed embryo, while in the latter case, the viability can be determined by observing the amount of fluorescent substance exuded.
Materials and Instruments
Plant seeds Move I. Materials, instrumentation and equipment For more product details, please visit Aladdin Scientific website.
UV fluorescent lamp Non-fluorescent white paper Blade Tweezers
1. Materials: Plant seeds.
2. Instrumentation: UV fluorescent lamp, non-fluorescent white paper, razor blade, tweezers.
II. Experimental steps
1. Direct observation method
This method is applicable to some pines and cypresses, cereals and some Rosaceae fruit tree seeds, but the inter-species differences are large. Use a razor blade to cut the seed in half lengthwise along the centerline of the embryo, take one half and place it on a non-fluorescent white paper, so that the cut side of the seed is facing upwards, and place it under an ultraviolet fluorescent lamp for irradiation and observation, and record. Viable seeds produce a bright orchid, orchid-purple, violet, or orchid-green fluorescence, and dead seeds are mostly yellow, brown to dull with numerous spots.
Observe 100 seeds, note the number of viable and dead seeds, estimate the germination rate and compare it with the actual germination rate obtained by the ordinary germination test method.
2. Fluorophore method on paper
Soaked intact seeds, according to a certain distance on wet filter paper (note that the water on the filter paper should not be too much, to prevent the fluorescent material dispersal) set aside for a certain period of time (a few hours), so that the filter paper (or even with the seeds) air-drying, and placed in the ultraviolet fluorescent lamps, can be seen around the dead seeds there is a circle of bright fluorescent clusters. The number of dead seeds can be determined according to the number of fluorescent clusters, and at least 100 seeds are measured each time, and the germination rate is estimated and compared with the actual germination rate measured by the common germination test method. This method has been applied to cruciferous plant seeds such as cabbage and radish with good results. However, it is not applicable to seeds that will diminish fluorescence or lose fluorescence after senescence and death, and the direct observation method should be used in the latter case.