How was the disease-resistant, fragrant and soft rice variety Jiuqi Xiang No. 1 bred?

I. Breeding process

1. Parent selection The internationally renowned rice variety Basmati, a superior rare fragrant-soft line obtained by mutation of Basmati original seed through solar radiation at this institute, and Xiangsimiao No. 2 were mixed and used as the male parent, with the conventional short-stalked, high-yielding, good-resistance and widely adaptable Qingzhen No. 8 as the female parent.

2. Progeny selection After a single plant was selected in the late season of 1991, various types of single panicles with medium-short stalks and plant-grain type similar to Xiangsimiao were selected respectively from the segregating materials of the F2 and F3 generations, then multi-generation selection and propagation and single-plant line comparative trials were carried out. In the late season of 1994, a line with relatively low amylose content and relatively high gel consistency was selected. In 1995, 3 lines with different plant heights, similar grain type, fragrant-soft character and high yield were bred and tested, and finally a shorter-stalked fragrant-soft simiao-type line with comprehensive traits and quality more ideal than the new parent was selected. After trial planting in 1996 and 1997, the results showed that this line had beautiful appearance quality of rice, possessed the characteristics of the fragrant-soft simiao type, and was competitive in the market, and it was named Jiuqi Xiang No. 1.

II. Breeding results

1. Yield performance After Jiuqi Xiang No. 1 was bred in 1996, up to now the cumulative demonstration area in the suburbs of Guangzhou, Leizhou, Meizhou, Zhongshan, Zhanjiang, Huiyang, northern Guangdong in this province and Ji'an in Jiangxi Province and other places has reached 500,000 mu. In the late season of 1999, it participated in the Guangzhou municipal regional trial, with an average yield of 325.0 kg per mu across 3 trial sites, ranking third among 17 participating varieties, increasing by 11.7 kg and 4.1% over the control variety Qishanzhan, increasing by 1.7 kg and 0.6% over the control variety Jingxian 89, increasing by 73.7 kg and 33.1% over Bataizaoxiang, increasing by more than 200 kg over Basmati, and slightly increasing yield compared with Xiangsimiao No. 2. In trial planting in Zengcheng and various places, this variety generally yields 360-400 kg per mu, and can reach 500 kg at high yield, and is deeply praised by farmers.

2. Agronomic traits Jiuqi Xiang No. 1 is a medium-maturity variety of early indica fragrant rice, with a whole growth period of about 125 days in the early season and about 110 days in the late season, a plant height of about 100 cm, medium tillering ability and ear-bearing rate, about 200,000 effective panicles per mu, an average of 150 filled grains per panicle, a seed-setting rate of 75%, and a 1000-grain weight of 16 jin. It is suitable for planting in sandy loam soil with medium to medium-high fertility and in environments with good water quality and large day-night temperature difference, and the quality and stable yield are even better when planted in the late season.

3. Resistance According to the identification by the Plant Protection Research Institute of the Guangdong Academy of Agricultural Sciences, this variety is highly resistant to rice blast, with a total resistance frequency of 90%, among which the resistance frequency to the medium B group and medium C group is 100%. The reaction to bacterial leaf blight by artificial inoculation identification is grade 9, which is highly susceptible (according to many years of planting in the Guangzhou area, this disease is rarely found). When planted in various types of areas, it shows relatively good resistance to leaf roller and rice planthopper.

4. Quality The rice of Jiuqi Xiang No. 1 was tested by the Rice and Rice Products Quality Testing Center of the Ministry of Agriculture, and the results showed that 10 indicators including brown rice rate, milled rice rate, head rice rate, length-width ratio, chalkiness rate, chalkiness degree, transparency, alkali spreading value, gel consistency and protein content all reached the first-grade standard of high-quality rice, and grain length and amylose content reached the second-grade standard of high-quality rice. The comprehensive evaluation result of rice quality is better than the domestic high-quality rice variety Zhou 903, and comparable to the foreign high-quality rice top-grade Thai fragrant rice. Experts from the Guangdong Provincial Genetics Society identified and held that: the breeding of this variety has reached the advanced level within the province. Jiuqi Xiang No. 1 has reached a relatively high level in yield, resistance and rice taste.

III. Processing, utilization and economic benefits

Since 1998, this variety has been successively used by production manufacturers such as the "Suizhen brand" fragrant simiao rice processing factory of this institute, the "Jufu brand" high-quality rice factory of the Guangdong Academy of Agricultural Sciences, the "Gualu brand" high-quality simiao rice factory of the Zengcheng City Agriculture Bureau, the "Lixin brand" high-quality simiao rice factory of Zhongxin Town, Zengcheng City, and the "Taiji brand" high-quality rice processing factory of Zhucun Town, Zengcheng City, to produce fragrant-soft characteristic rice products. In early 1999, the "Gualu brand" nutritional health-care rice product produced by the simiao rice factory of the Zengcheng City Agriculture Bureau using Jiuqi Xiang No. 1 rice and characteristic rice such as Zengye simiao was exhibited and evaluated in Macao, China, and as a result won the international gold award of the "Second Asian International Famous, Excellent and New Product, New Technology, New Invention @#@119@#@"; the "Gualu brand" super-grade simiao rice product produced using the rice of this variety and other specially excellent rice also won the gold award of the "1999 China Fourth International Agricultural Exposition" and was recognized as a Chinese famous-brand product.

According to investigation, in 1999 the market price of late indica paddy in Zengcheng City: Jiuqi Xiang No. 1 was 100-125 yuan per 50 kg, and calculated at a yield of 360 kg per mu, the output value per mu was 720-900 yuan, while grade-three paddy was about 43 yuan per 50 kg, and calculated at a yield of 450 kg per mu, the output value per mu was only 387 yuan. Jiuqi Xiang No. 1 and other high-quality paddy processed according to formula into fragrant-type rice products @#@136@#@ (formula fragrant-soft rice 4.5 yuan per kg, single high-quality rice about 2.5 yuan per kg, grade-three rice about 1.5 kg per kg) also achieved relatively good economic benefits. Last year the paddy price of this variety was 85-90 yuan per 50 kg, and the planting benefit was still relatively good.

IV. Key cultivation points

For early-season planting, this variety is suitable for sowing from late February to early March and transplanting before Qingming; for late-season planting, it is suitable for sowing in mid-July and transplanting before the Start of Autumn. The seed rate per mu in the field is 1.5 kg for seedling-throwing cultivation and 2 kg for transplanting cultivation. Fertilizer application in field cultivation should be at a medium-high level; base fertilizer is required to be organic fertilizer or compound fertilizer; early-stage fertilizer should be applied early and heavily; about 20 days after transplanting, do a good job of draining and sunning the field and apply lime or plant ash 1-2 times, then create conditions to apply topdressing for the middle-stage young panicle development and enlargement; apply nitrogen and potassium fertilizer from the initial heading stage to the full heading stage; keep the field moist until maturity in the middle and late stages, which is beneficial to improving the seed-setting rate. In addition, attention should also be paid to preventing and controlling rodent damage.