Breeding method of early-maturing cotton variety

Abstract

The invention discloses a breeding method of an early-maturing cotton variety, and relates to the technical field of variety breeding. Comprising the following steps: 1) parent selection and hybridization; 2) selfing screening; 3) hybridizing and fusing; 4) performing selfing purification; and 5) variety identification and breeding. Through a designed hybridization strategy, polymerization and fixation of premature characters are accelerated, and compared with a traditional breeding method, the breeding period is remarkably shortened. And through multi-generation selfing purification, the stability and the consistency of premature characters are ensured, and the adaptability and the popularization value of a new variety are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of variety breeding, and more particularly to a breeding method for early-maturing cotton varieties. Background Art

[0002] Cotton is one of the main cash crops in my country. There are three major cotton-growing areas in my country, namely the Yellow River Basin Cotton Area, which includes Shandong, Hebei, Henan and other places; the Yangtze River Basin Cotton Area, which includes Hunan, Hubei, Jiangsu, Anhui and other places; and the Xinjiang Cotton Area. As an important cash crop and strategic resource, the cotton industry occupies an important position in the national economy. The results of cotton breeding with a variety of excellent traits have a vital scientific and technological contribution to the increase in cotton production and the prosperity of the industry. Yield, disease resistance, and fiber quality have always been the preferred breeding targets for cotton.

[0003] With the development of modern agriculture, cotton production has an increasingly urgent need for new varieties that are early maturing, high-quality, high-yielding, and suitable for mechanized harvesting. For cotton breeding, early maturity is an even more important agronomic trait. The suitability of the variety's growing period directly affects the variety's utilization of light and temperature resources in a specific area and its potential for increasing yields. The early maturity of cotton is a quantitative trait controlled by multiple genes. By shortening the variety's growing period and genetically improving its early maturity through breeding and biological methods, the multiple cropping index in the wheat-cotton or oil-cotton double-cropping cotton areas in the Yangtze River and Yellow River basins can be increased. In the cotton areas of northern Xinjiang with a short frost-free period, full use can be made of light and heat resources to avoid low temperature damage caused by late spring cold in the early growth period and early frost damage in the late growth period, thereby ensuring cotton yield and quality.

[0004] The growth period is the number of days from sowing to the boll opening period (the date when 50% of the cotton plants have their first boll opening). This is the main indicator for measuring the early maturity of cotton varieties. Generally, the shorter the growth period, the earlier the variety matures. In the upland cotton varieties in the cotton-growing areas of the Yellow River and Yangtze River basins, the growth period of early-maturing cotton varieties is 101-120 days, which is suitable for planting after the harvest of crops and vegetables such as wheat, barley, rapeseed, potatoes and garlic, with two harvests a year. It is also suitable for planting in the early-maturing cotton areas of the northwest inland, especially in the northern Xinjiang. The growth period of medium-early maturing varieties is 121-130 days, which is suitable for intercropping of wheat and cotton, and is also suitable for planting in the northwest inland cotton areas, especially in the southern Xinjiang. The growth period of medium-maturing varieties is about 140 days, which can only be planted once or transplanted in the cotton-growing areas of the Yellow River and Yangtze River basins.

[0005] Early-maturing cotton varieties can be harvested earlier, avoiding adverse climatic conditions in the later period and improving yield stability. However, traditional breeding methods have long cycles and low efficiency, and are difficult to meet the needs of rapid breeding. Therefore, it is of great practical significance to develop an efficient and precise hybrid breeding technology to accelerate the selection of new early-maturing cotton varieties.

[0006] Therefore, providing a breeding method for early-maturing cotton varieties is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0007] In view of this, the present invention provides a breeding method for early-maturing cotton varieties.

[0008] In order to achieve the above object, the present invention adopts the following technical solution:

[0009] A method for breeding early-maturing cotton varieties comprises the following steps:

[0010] 1) Parent selection and hybridization:

[0011] Select Early Maturity Cotton No. 1 as the female parent and Late Maturity Cotton No. 1 as the male parent for hybridization to obtain the first generation hybrid F1-1;

[0012] Select Early-maturing Cotton No. 2 as the female parent and Late-maturing Cotton No. 2 as the male parent for hybridization to obtain the first-generation hybrid F1-2;

[0013] 2) Self-pollination screening:

[0014] Self-pollinating F1-1 and F1-2 respectively to obtain F2-1 and F2-2, and selecting the offspring showing early-maturing characteristics from F2-1 and F2-2 to obtain early-maturing offspring of F2-1 and early-maturing offspring of F2-2;

[0015] 3) Hybridization fusion:

[0016] The selected F2-1 early-maturing offspring is used as the female parent and the F2-2 early-maturing offspring is used as the male parent for hybridization to obtain the F3 generation early-maturing offspring;

[0017] 4) Self-pollination purification:

[0018] The excellent early-maturing individuals in the F3 generation are self-pollinated to produce the F4 generation; through multiple generations of self-pollination, the early-maturing genes are further purified to ensure the stability and consistency of the early-maturing traits;

[0019] 5) Variety identification and breeding:

[0020] A comprehensive field performance evaluation is conducted on the F4 generation and self-pollinated offspring plants, including early maturity, yield, fiber quality and other traits, to select the best early-maturing new cotton varieties.

[0021] Furthermore, in step 4), in order to increase the selection pressure on early maturity, late sowing screening is carried out, and the sowing date is postponed to June 15-20, and topping is carried out on August 10-15.

[0022] Furthermore, in step 5), the offspring of the new variety are screened by delayed sowing for 2-3 consecutive years to ensure that the early maturity, boll setting and boll weight of the cotton variety are synergistically improved.

[0023] It can be seen from the above technical solution that, compared with the prior art, the beneficial effects of the present invention are:

[0024] The invention accelerates the aggregation and fixation of early-maturing traits through the designed hybridization strategy, significantly shortening the breeding cycle compared with the traditional breeding method. Through multi-generation self-pollination purification, the stability and consistency of early-maturing traits are ensured, and the adaptability and promotion value of new varieties are improved. Using different parents for hybridization increases the chance of gene recombination, providing rich genetic materials for breeding new cotton varieties with high yield, high quality and early maturing.

[0025] The present invention aims at the major scientific and technological needs of the cotton industry for mechanized harvesting and simplified cotton planting. By means of key technical links such as reasonable configuration of parents, improvement of nutritional growth, early seed-finger selection and increasing selection pressure for early maturity by delaying sowing time, the early maturity of cotton is improved, and technical support is provided for the breeding of early and high-yield cotton varieties with a short growing period, strong growth, good yield, strong boll setting ability and high flowering rate before frost. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Example 1

[0028] Parent selection and hybridization:

[0029] 1) Selecting early-maturing cotton No. 1 (Xinlu Zao 33) as the female parent and late-maturing cotton No. 1 (Hongmian 30) as the male parent for hybridization to obtain the first-generation hybrid F1-1;

[0030] The early-maturing cotton No. 2 (Xiangmian Zao No. 3) was selected as the female parent and the late-maturing cotton No. 2 (Yumian No. 46) was selected as the male parent for hybridization to obtain the first-generation hybrid F1-2;

[0031] 2) Self-pollination screening:

[0032] Self-pollinate F1-1 and F1-2 to obtain F2-1 and F2-2, and screen and identify the plant lines from F2-1 and F2-2 to ensure that the selected plant lines maintain strong boll-setting ability of the early-mature cotton varieties on the basis of early maturity;

[0033] The F2-1 early-maturing offspring and the F2-2 early-maturing offspring were obtained;

[0034] 3) Hybridization fusion:

[0035] The selected F2-1 early-maturing offspring is used as the female parent and the F2-2 early-maturing offspring is used as the male parent for hybridization to obtain the F3 generation early-maturing offspring;

[0036] Through hybridization, the vegetative growth of early-maturing cotton varieties is improved, so that the F3 generation of cotton has strong vegetative growth, plant height reaches 85-95cm (5-15cm higher than the F1 generation), the root system is well-developed, and the supply of photosynthetic products is improved;

[0037] 4) Self-pollination purification:

[0038] The excellent early-maturing individuals in the F3 generation are self-pollinated to produce the F4 generation; through multiple generations of self-pollination, the early-maturing genes are further purified to ensure the stability and consistency of the early-maturing traits;

[0039] To increase the selection pressure for early maturity, the sowing date was postponed to June 15-20, the topping was done on August 10-15, and the boll opening rate reached more than 50% on October 25.

[0040] In a shortened growing season, the growth cycle is completed faster, and cotton materials or individual plants with a single boll weight of more than 5.5g are selected.

[0041] 5) Variety identification and breeding:

[0042] A comprehensive field performance evaluation of the F4 generation and self-pollinated offspring plants, including early maturity, yield, fiber quality and other traits, was conducted to select the best early-maturing cotton new varieties. The offspring of the genetic population were screened for 2-3 consecutive years of late sowing to ensure that the early maturity, boll setting and boll weight of the cotton varieties were synergistically improved.

[0043] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for breeding early-maturing cotton varieties, characterized in that: The following steps are involved: 1) Parent selection and hybridization: Select Early Maturity Cotton No. 1 as the female parent and Late Maturity Cotton No. 1 as the male parent for hybridization to obtain the first generation hybrid F1-1; Select Early-maturing Cotton No. 2 as the female parent and Late-maturing Cotton No. 2 as the male parent for hybridization to obtain the first-generation hybrid F1-2; 2) Self-pollination screening: Self-pollinating F1-1 and F1-2 respectively to obtain F2-1 and F2-2, and selecting the offspring showing early-maturing characteristics from F2-1 and F2-2 to obtain early-maturing offspring of F2-1 and early-maturing offspring of F2-2; 3) Hybridization fusion: The selected F2-1 early-maturing offspring is used as the female parent and the F2-2 early-maturing offspring is used as the male parent for hybridization to obtain the F3 generation early-maturing offspring; 4) Self-pollination purification: The superior early-maturing individuals in the F3 generation are self-pollinated to produce the F4 generation; Through multiple generations of self-pollination, the early-maturing gene is further purified to ensure the stability and consistency of the early-maturing trait; 5) Variety identification and breeding: A comprehensive field performance evaluation is conducted on the F4 generation and self-pollinated offspring plants, including early maturity, yield, fiber quality and other traits, to select the best early-maturing new cotton varieties.

2. The breeding method according to claim 1, characterized in that: In step 4), in order to increase the selection pressure for early maturity, late sowing screening was carried out, and the sowing date was postponed to June 15-20, and topping was carried out on August 10-15.

3. The breeding method according to claim 2, characterized in that: In step 5), the offspring of the new variety are screened for 2-3 consecutive years to ensure that the early maturity, boll setting and boll weight of the cotton variety are synergistically improved.