Cultivation method of indica type three-line hybrid rice with high alkali elimination value

Abstract

The invention relates to a cultivation method of indica type three-line hybrid rice with high alkali elimination value, which comprises the following steps: selecting a sterile line of Gangyou 9605 to be improved as a female parent, and hybridizing with a restoring line of Sichuan you 1618 with high alkali elimination value to obtain an F1 filial generation; and sowing the obtained seeds of the F1 filial generation, and after the seeds are mature, backcrossing the seeds with the female parent Gangyou 9605 to obtain BC1F1 generation seeds. The obtained seeds of the BC1F1 generation are sown, after the seeds are mature, single plants with excellent characters are taken for selfing, and seeds of the BC1F2 generation are obtained. The obtained seeds of the BC1F1 generation are sown, and after the seeds are mature, the seeds and the male parent Chuanyou 1618 are subjected to backcross, and F2 filial generation is obtained. Performing continuous selfing on the obtained F2 filial generation to obtain plants with stable characters, so as to obtain the indica type three-line hybrid rice with high alkali elimination value.

Description

Technical Field

[0001] The invention relates to a method for cultivating indica three-line hybrid rice with high alkali-inhibition value, belonging to the technical field of hybrid rice breeding. Background Art

[0002] Alkali digestibility (ALD) is an important indicator of the endosperm texture and starch properties of grains, particularly rice, and is primarily used to assess rice's cooking and edible qualities and processing characteristics. It reflects the ability of starch in rice grains to swell and dissolve under alkaline conditions and is closely related to the rice's texture, including its firmness and stickiness. A high ALD generally indicates that the grain gelatinizes and softens more easily during cooking, resulting in better edible quality.

[0003] Gangyou 9605 boasts high yield, a moderate growth period, good resistance, and moderate susceptibility to rice blast, with a comprehensive blast index of 4.9 and 3.4 in the past two years, respectively, and a neck blast loss rate of 5, the highest level. It also exhibits strong heat resistance, capable of maintaining good growth and yield stability in high-temperature environments. However, its alkali-insoluble value is 4.2, and its gelatinization temperature is relatively high, requiring more advanced cooking conditions. During cooking, higher temperatures or longer cooking times are required to fully gelatinize the starch and achieve a soft rice. Rice may become more susceptible to reversion after cooling, especially after refrigeration or storage for a period of time, resulting in a noticeable deterioration in taste, which can affect the re-consumption of leftovers.

[0004] Therefore, we proposed a method for breeding indica three-line hybrid rice with high alkali-absorbing value to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for cultivating an indica three-line hybrid rice with a high alkali absorption value, thereby increasing the alkali absorption value of excellent plants and improving their taste.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for cultivating three-line indica hybrid rice with high alkali-absorbing value comprises the following steps:

[0008] Step 1: Select the sterile line of Gangyou 9605 to be improved as the female parent, and hybridize it with the restorer line of Chuanyou 1618 with a high alkali-tolerance value to obtain the F1 offspring.

[0009] Step 2: Sow the seeds of the obtained F1 offspring, and after they mature, backcross them with the mother plant Gangyou 9605 to obtain BC1F1 generation seeds.

[0010] Step 3: Sow the obtained BC1F1 generation seeds, and after they mature, select the single plants with good traits for self-pollination to obtain BC1F2 generation seeds.

[0011] Step 4: Sow the obtained BC1F1 generation seeds, and after they mature, backcross them with the father Sichuan You 1618 to obtain the F2 offspring.

[0012] Step 5: The obtained F2 progeny are continuously self-pollinated to obtain plants with stable traits, thereby obtaining an indica three-line hybrid rice with a high alkali-absorbing value.

[0013] Preferably, the plant with excellent traits is a plant that meets the requirements of green leaf sheaths, no coloration of anthocyanins in the second leaf blade and leaf auricles, no coloration of anthocyanins in the stem nodes, wrapped stem nodes at the base of the stem, and white stigma.

[0014] Preferably, backcrossing is performed for 2-3 generations in step 2.

[0015] Preferably, the self-pollination in step 3 is carried out for 4-5 generations.

[0016] Preferably, backcrossing is performed for 2-3 generations in step 4.

[0017] Preferably, in step five, self-pollination is performed for 4-5 generations.

[0018] The present invention has the following beneficial effects: Gangyou 9605 has the advantages of high yield, a moderate growth period, good resistance, and strong heat resistance, and can maintain a good growth state and stable yield in high temperature environments. However, its alkali digestibility is low and its gelatinization temperature is high, requiring more cooking conditions, and higher temperatures or longer cooking times are required to fully gelatinize the starch. This breeding method can produce an indica three-line hybrid rice with high yield, good resistance, strong heat resistance, and a high alkali digestibility. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0020] A method for cultivating three-line indica hybrid rice with high alkali-absorbing value comprises the following steps:

[0021] Step 1: Select the sterile line of Gangyou 9605 to be improved as the female parent, and hybridize it with the restorer line of Chuanyou 1618 with a high alkali-tolerance value to obtain the F1 offspring.

[0022] Step 2: Sow the seeds of the obtained F1 offspring, generally from early March to early April, with a sowing rate of 10.0 kg per mu in the nursery field. After they mature, backcross them with the mother plant Gangyou 9605 to obtain BC1F1 generation seeds.

[0023] Step 3: Sow the BC1F1 generation seeds. Transplant seedlings raised in water at approximately 5.0 leaves, within 30 days of seedling age. Plant rows 20.0 cm x 30.0 cm apart, with a minimum of 70,000 seedlings per acre. After maturity, select individual plants with excellent traits for self-pollination to obtain BC1F2 generation seeds.

[0024] Step 4: Sow the obtained BC1F1 generation seeds, and after they mature, backcross them with the father Sichuan You 1618 to obtain the F2 offspring.

[0025] Step 5: Continuously self-pollinate the obtained F2 progeny, apply fertilizer scientifically, and sow and plant early at the right time; apply sufficient base fertilizer, mainly rice-specific fertilizer and organic fertilizer, to obtain plants with stable traits, and obtain a high-alkali-consumption indica three-line hybrid rice, Huiyou 527.

[0026] The results are shown in the following table:

[0027] Table 1 Hybrid statistical data

[0028] name Plant height (cm) Total number of grains per ear Fruit setting rate (%) Alkali elimination value (grade) Gangyou 9605 124.6 208.2 86.2 4.2 <![CDATA[F1 offspring]]> 123.8 191.5 85.4 5.9 <![CDATA[BC1F1 progeny]]> 123.6 192.3 85.9 6.0 <![CDATA[BC1F2 offspring]]> 123.9 189.4 84.9 6.6 <![CDATA[F2 progeny]]> 123.8 189.2 85.1 6.8

[0029] In summary:

[0030] The cultivation method used in the present invention not only retains the advantages of Gangyou 9605, such as high yield, moderate growth period and good resistance, but also improves the alkali consumption value, thereby ensuring that the hybrid rice has a soft taste, a soft texture, moderate viscosity, and is easy to chew, making it suitable for the elderly, children or consumers who prefer soft food. The method also has the advantages of sufficient gelatinization, more thorough destruction of the starch granule structure, easier decomposition by human digestive enzymes, and higher digestion and absorption rate. Thus, the Huiyou 527 with a higher alkali consumption value is cultivated without reducing its yield.

[0031] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions merely illustrate the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for cultivating three-line indica hybrid rice with high alkalinity, characterized in that: The steps include: Step 1: Select the sterile line of Gangyou 9605 to be improved as the female parent, and hybridize it with the restorer line of Chuanyou 1618 with a high alkali-tolerance value to obtain the F1 offspring. Step 2: Sow the seeds of the obtained F1 offspring, and after they mature, backcross them with the mother plant Gangyou 9605 to obtain BC1F1 generation seeds. Step 3: Sow the obtained BC1F1 generation seeds, and after they mature, select the single plants with good traits for self-pollination to obtain BC1F2 generation seeds. Step 4: Sow the obtained BC1F1 generation seeds, and after they mature, backcross them with the father Sichuan You 1618 to obtain the F2 offspring. Step 5: The obtained F2 progeny are continuously self-pollinated to obtain plants with stable traits, thereby obtaining an indica three-line hybrid rice with a high alkali-absorbing value.

2. The method for cultivating a high alkalinity-absorbing indica three-line hybrid rice according to claim 1, wherein: The plants with excellent traits are those that have green leaf sheaths, no anthocyanin coloring in the second leaf blade and leaf auricles, no anthocyanin coloring in the stem nodes, wrapped stem nodes at the base of the stem, and white stigmas.