Are the gametes produced by the doubling of colchicine in the plant haploid or diploid

Normal diploid plants that have been doubled with colchicine produce normal gametes that are diploid, haploid but not diploid The concept of haploid needs to be clear here.

Chromosomal ploidy refers to the number of homologous chromosomes in a cell, and only one set of them is called a "monoset" or "haploid". It is important to note that haploid is distinguished from monoploid (an individual with a set of chromosomes in somatic cells). Some haploid organisms have more than one set of chromosomes in their somatic cells.

The vast majority of organisms are diploid organisms, and their haploid somatic cells contain one chromosome set, and if the original species itself is polyploid, then its haploid somatic cells must contain more than one chromosome set. For example, the haploid of tetraploid rice contains two sets of chromosomes, and the haploid of hexaploid wheat contains three sets of chromosomes. }

and the concept of diploidy.

Any organism that develops from a fertilized egg and contains two sets of chromosomes in its somatic cells is called diploid. It can be expressed in 2n. Humans and almost all higher animals, as well as more than half of higher plants, are diploid. }

Your question itself is questionable, "Are the gametes produced by the doubling of colchicine in plants haploid or diploid" Plants have tetraploid and octaploid, most of which are diploid. However, the direct development of egg cells without fertilization is haploid, the direct development of gametes is haploid, and the number of chromosomes in plants is only doubled by colchicine, not diploident. Don't listen to the indiscriminate blowing of water on the first floor.

Definition 1: A cell or organism that contains only one set of chromosomes. The gametes of most animals and plants are haploid, and the organisms that develop directly without combining gametes are also haploid.

At first glance, you are not familiar with the textbook, the old students have to memorize the textbook, and the multiple-choice questions, fill-in-the-blanks, and experimental questions (experiments in the textbook) are all from the concept of the textbook, (personal experience).

Haploid, as long as it is a gamete, it is haploid.

In the case of a haploid (a set of chromosomes) formed by diploid, it is diploid after colchicine treatment.

If it is a haploid formed by polyploidy, it is polyploid after colchicine treatment. For example, the haploid of tetraploid is two sets of chromosomes that become tetraploid (polyploidy) after being doubled by colchicine.

Haploids may be heterozygous after colchicine treatment, Reason:

1) When a haploid plant contains only one chromosome set, the plant treated with colchicine will have two chromosome sets, which must be homozygous. For example, haploid plants with genotype A were treated with colchicine to obtain homozygous for AA, and haploid plants with genotype A were treated with colchicine to obtain homozygous for AA.

2) When a haploid plant contains two or more chromosome sets, it can be considered in two cases.

If the parents of a haploid plant are heteropolyploid, or if they are formed by the crossing of two different organisms, the plant must also be homozygous after colchicine treatment. For example, the 9 chromosomes of radish (2n=18) are written as R, and the 9 chromosomes of cabbage (2n=18) are written as B, then the F1 of the two hybrids is Rb, which is haploid, and the Rrbb obtained by F1 treatment with colchicine must be homozygous.

Haploid plants with homopolyploid parents are not necessarily homozygous after colchicine treatment. For example, tetraploid mandala (4n=48), assuming that its genotype is AAAA, its haploid has 2 chromosome sets, and the genetic composition of the haploid has 3 kinds, such as AA, AA, and AA, among which AA is treated with colchicine to obtain heterozygous (dipnosomes) with genotype AAAA.

Therefore, after treating haploid plants with colchicine, the result is not necessarily homozygous, but may be heterozygous.

The number of chromosomes of a haploid plant is not necessarily 1, for example, if it is originally 4ploid, its haploid contains 2 chromosome groups, and the number of chromosomes obtained after using colchicine on it is 4ploid.

Haploid refers to the development of gametes, which can be more than one chromosome or one chromosome set, if it is a haploid plant developed into a gamete with two chromosome groups, it is tetraploid after doubling.

The original haploid does not necessarily have only one set of chromosomes.

Of course not.

The so-called haploid refers to an individual that develops directly from an unfertilized gamete, but it is important to note that there is not necessarily only one chromosome set.

For example, if a plant is tetraploid, it will have two sets of chromosomes in its gametes, and the individual that develops directly from the unfertilized gamete is haploid. Treatment of this haploid with colchicine results in four sets of chromosomes, which are called tetraploids.

What turned out to be diploid became tetraploid.

Textbook P51 Multiple Choice Question 3 "In breeding, haploids are treated with colchicine in order to obtain: (a) diploid; (b) polyploidy; (c) heterozygous; (d) homozygous". The answer given in the teaching staff is d.

The concept of homozygotes in textbook P24 is "A plant with a combination of DD and DD is an individual developed from a zygote formed by the combination of gametes of the same gene, which is called homozygosity." Homozygous children are able to inherit stably and their inbred offspring do not undergo trait segregation. Let's look at the case of a haplotype of sport:

Individuals with a genotype of AAAA can produce three types of gametes: AA, AA, and AA. The pollen of the individual was taken for anther culture in vitro to obtain three haploids of aa, aa and aa, and then the genotype of aa, aa and aa were treated with colchicine respectively, and the genotype of aa, a and a three tetraploids could be obtained, obviously the genotype aaaa and aa individuals were homozygous, but the genotype of aaaa individuals formed by the inbred offspring of aaaa individuals and the proportion were as follows:

Gametes 1aa4aa1aa

1aa1aaaa4aaaa1aaaa

4aa4aaaa16aaaa4aaaa

1aa1aaaa4aaaa1aaaa

As mentioned in the table above, only 1 2 individuals with the same genotype and 35 36 individuals with the same genotype as the parents have inbred offspring of individuals with the same genotype, and it is clear that there has been trait segregation, so individuals with genotype AAAA cannot be called homozygous. The author believes that the above question is wrong.

The precise definition of diploidy is that any biological individual that develops from a fertilized egg and contains two sets of chromosomes in its somatic cells is called diploid. In addition, plants grown from diploid somatic cells and plants that have been doubled by doubling the number of chromosomes from haploids containing only one set of chromosomes are also called diploids.

Your understanding is a bit lacking.

Assuming that the genotype of maize is AA, the genotype after treatment with colchicine is AAAA, and the pollen produced is AA, AA, AA, and the haploid obtained by anther in vitro culture has AA, AA, AA, so there are both homozygous and heterozygous.