The work of artificial algae cultivation in China started late, and many other types of seaweed are still not mature. At present, kelp which is cultivated on a large scale in China is a new variety cultivated artificially. The following is a small series for everyone to introduce the breeding method of kelp in detail.
(1) Select breeding
1. Breeding methods
Directional selection In the kelp thickening stage, according to the breeding goal of high iodine and high yield of kelp, the algae with large and medium-belt width and thick leaf are selected firstly, then the algae with high iodine content are screened, and then directional culture is formed. A group of good traits.
Self-crossing The kelp male and female gametophytes with excellent traits are white-crossed and selected to obtain a "pure line" with high iodine and high yield. X-ray treatment The kelp gametophyte was treated with a 4000 lux dose of X-ray, followed by self-crossing and orientation selection.
2. Breeding of new varieties of high iodine and high yield kelp
Twenty-nine high-iodine individuals were selected from the near-drying algae body. After continuous self-crossing and directed cultivation, two inbred lines with high iodine and high yield and good traits were selected.
(1) No. 860 is a long-leaf line with long leaves and yield, suitable for firing at higher temperatures. At the same time, it has the advantages of high iodine content and low water content. The disadvantage is that the area formed by the robe is small.
(2) No. 170 is a method in which the separated female gametophyte is irradiated with x-rays and self-cultivated using the surviving gametophytes. It is characterized by low water content of algae and iodine content. The algae grows faster under high temperature and has high yield.
In addition to the death of two new kelp varieties, China has also cultivated long g1 type Haiyu No.1, No.2, No.4, thick-leaf type of Retire No.3 and other excellent varieties, and the plant length and The study of stem length inheritance.
(2) Single sports species
In the early 1970s, China carried out research on kelp haplotypes, cultivating kelp singly and cultivating seedlings in the sea.
1. Single robes body cultivation The kelp haploid cultivation is to use the mature female eggs of the gametophyte to obtain a single stalk body. The method comprises the steps of separating the male and female gametophytes by micro-tube separation method, and culturing at a temperature of 5-12 ° C and a light intensity of 1500-2500 Lx for 10 h/d. After the female gametophyte matures, the eggs are discharged, and a few of them are lined up.
Parthenogenesis forms young and broad-body, and grows into a single bubble body in the commercial area. At present, only the female robes are cultivated, and the male robes have not yet been obtained.
2, the ploidy of the single robes body in the female robes on the surface of the sea can form robes vesicles on the surface, release the robes after maturity, the buds are attached to the germination and all form a female match: wide body. The female gametophyte forms a female robes after parthenogenesis. The life cycle of the female body is completed. Regarding the ploidy of the female robes, it is believed that the female sporophytes have a problem of natural doubling of chromosomes during the growth process, but the female spores are confirmed by chromosome examination.
The acquisition of the female robes provides favorable conditions for the utilization of kelp heterosis. "Shuanghai No.1" is a new variety obtained by using female robes as the female parent, hybrid with thick-leaf hybrid kelp, and then selected by white cross. It has M[sheet width, thickness and uniformity, and the area of ​​the sac is large. High iodine content.
(3) Cross breeding
1. Intraspecific hybridization
Hybrid kelp hybridization is a new type of cultivating and breeding using the same kelp as a parent. In China, the research on cross-breeding breeding in kelp has started earlier, and some excellent hybrids have been promoted for cultivation and production. The research and application of strength is at the advanced level in the world. In addition to “Singhai No.1â€, the new “Haiza No.1†variety, which was bred by parents No. 860 and No. 170, was proved to be an excellent high-yield variety after extensive cultivation experiments. No. 1 is the use of cultivated kelp to hybridize with the seaweed that grows naturally on the seabed. The descendants of the kelp are cultivated through continuous white text breeding, and the products of the 122V produce 25-30t dry goods.
2. Interspecific hybridization
The interspecific hybridization of kelp is carried out by breeding and breeding new varieties using different types of parents. Japan began interspecific hybridization studies of kelp in the late 1970s. Using the Japanese-made long kelp, Limin kelp, ghost kelp, Sanshi kelp, narrow-leaved kelp, kelp male and female gametophyte, the interspecific hybridization test was carried out, the fertilization rate of each hybrid combination was determined, and the hybrid kelp seedling well was cultivated indoors and The sea area was cultured as a hybrid kelp adult, and the heterosis combination of growth, length and thickness of algae and the genetic relationship between kelp species were discussed.
At the end of the rib period in China, we introduced six kinds of kelp snakes from Japan, and carried out research on kelp seed hybrid breeding. On the basis of completing various kelp ecological conditions, we selectively cultivated 18 combined ribs. The hybrid kelp seedlings were cultivated as hybrid kelp adults on the floating area of ​​the sea area, and the length and width of the algae of the hybrids were determined.
The results showed that the 13 combinations showed heterosis in the length of algae and 9 combinations in the growth of algae width. Among them, the hybrids of the six combinations in the length and width of algae were obvious, showing a wide range of applications. prospect. Since the 1990s, China's use of kelp and Japanese long kelp hybrids, the new "Smoke--" new varieties have the advantages of large algae, fast growth, high yield, has been widely applied and popularized.
Therefore, there are three methods of kelp breeding, such as breeding, haplotype, and crossbreeding. Have you learned it? If you don't understand, you can communicate with each other in the comment area.
Wenzhou Celecare Medical Instruments Co.,Ltd , https://www.celecaremed.com