Plant polyploids are plants that have more than three sets of chromosome sets per cell. Common plants in nature are mostly diploid, and research has found some natural polyploids with increased chromosome number, robust growth, enlarged organs, higher nutrient content, and increased resistance to stress, making them ideal breeding materials. In addition to natural polyploids, polyploids can actually be induced artificially. There are many artificial induced polyploid methods, such as: physical induced polyploidy, chemical induced polyploidy and other methods.
Principle
Physical induction: Polyploidy can be obtained by extreme temperatures, temperature excitation, rays, and other methods.
Chemical induction: chemical methods of inducing polyploidy, i.e., using chemical reagents to treat plants to double their chromosomes, is by far the most commonly used method.
Other methods: somatic cell fusion, endosperm culture, Agrobacterium-mediated methods.
Appliance
Provide theoretical basis for breeding in agricultural development and application in production.
Operation method
colchicine-induced method
Principle
Plant polyploids are plants that have more than three sets of chromosome sets in each cell. There are many ways to artificially induce polyploidy, this experiment uses colchicine to inhibit the formation of spindle humorous filaments, so that the chromosomes replicated can not move to the poles, and at the same time the cell does not divide, thus forming the principle of polyploidy, with the appropriate concentration of colchicine treatment of onion or garlic root tips, to be the tip of the root tip after the expansion of the preparation of the observation, can be found polyploid cells.
Materials and Instruments
Garlic Onion Corn Seeds Plant Seedlings Move 1. Seed germination: rye or barley seeds were washed with tap water and soaked for half an hour, and then transferred to a petri dish with moistened absorbent paper, and germinated in an incubator at 25℃ for 36～48h. 2. Colchicine treatment: seed germination to the root length of 0.5 ~ 1.0cm, leaving the germinated seeds, washed with water, absorbent water, add 0.02% colchicine solution, so that the sprouted root tip immersed in colchicine solution. Cover the petri dish and place it in a 25℃ incubator for 24h. 3. Observation and fixation of root tip: After treatment, the root tip was enlarged and shaped like a drum whip. Take this root tip, put in penicillin bottle, with methanol: glacial acetic acid (3:1) fixative 6h, discard the fixative, continue the following steps or add 70% alcohol at 4 ℃ in the refrigerator for storage. 4. Root tip treatment and pressing: discard the fixative or alcohol, add 1 mol/L hydrochloric acid preheated at 60 ℃, dissociate in a water bath at 60 ℃ for 10 min. discard the hydrochloric acid, and wash the root tip several times with tap water to thoroughly wash the hydrochloric acid. After staining with magenta carbolic acid, the root tip could be pressed and observed to identify the chromosome doubling of the root tip cells. For more product details, please visit Aladdin Scientific website.
Colchicine
Microscope Constant temperature incubator Constant temperature water bath Tweezers Slides and coverslips