Use of Exotic Germplasm in China

Major introduced cultivars

Fourteen major progenitors of Chinese wheats were released from 1949 to the 1980s. Jinn (1983) calls these progenitors centroparents. They included Chinese landraces, several improved Chinese lines, and introduced
cultivars from Italy, Chile, and the U.S. (Table 15).

Table 15. "Centroparents" in Chinese wheats, their origin and number of progeny

Source: Jin (1983).

Qiao et al. (1994) analyzed the characteristics and pedigrees of major cultivars grown in Zone II (the winter
wheat region of the Yellow and Huai River Valleys) during the 1980s (Table 16).

Table 16. Genealogical profile of the top ten cultivars in Zone II, China, 1980s and early 1990s

Source: Qiao et al. (1994).

Their geneological profile shows the early generations in their pedigrees to be based on key Chinese landraces such as Maza mai and Youzi mai. Foreign parents introduced before the 1950s included Quality (Australia), Mentana (Italy), Villa Glori (Italy), Early Premium (U.S.), and Triumph (U.S.). In the 1950s, important foreign parents included Suwon 86 (Korea), Abbondanza (Italy), and Funo (Italy). The Chilean parents Orofen, and Rulofen (of Italian parentage), as well as other Italian lines, were bred into their pedigrees in the 1960s. In the early 1970s, selections from the Romanian cross Lovrin, as well as some materials from the Former Soviet Union and Germany, were introduced into their pedigrees.

Cooperation with foreign institutions, such as Cornell University and the Rockefeller Foundation, as well as various foreign missionary organizations, began during the 1920s and 1930s and resulted in the introduction of modern plant breeding science (Hsu 1982). When the People's Republic of China was founded, there were over 100 agricultural experiment stations at the national and provincial levels, 25 national agricultural colleges, and 9 agricultural schools. As a whole, there was no extension service, and educational-experimental efforts were too small to affect productivity. But some of the foreign cultivars introduced from the U.S., Australia, and Europe during this period provided the basis for later cultivar improvement. Major foreign cultivars that were introduced before 1949 and that played an important role in plant breeding after the founding of the People's Republic of China included Quality, Noongar, and Fawn (Australia); Villa Glori, Mentana, and Ardito (Italy); and Triumph and Early Premium (U.S.).

Quality, called Biyu mai, was introduced in 1923 and extended to a large area in both winter and spring wheat zones during the 1950s. Quality had broad adaptation, drought tolerance, and resistance to leaf and stripe rust. Two of Quality's descendants, Liyin and Bima, were both among the early improved cultivars that were widely grown and that became major parents in the national breeding program. Noongar (Shannian 2) was extended in northern spring wheat zones in 1950s and, at the time, was highly resistant to stripe and leaf rust. Fawn (Chuanfu mai), which was resistant to stripe rust and loose smut, was introduced in 1938 and extended in Sichuan Province. Fawn and Quality are the parents of the famous cultivar Wuyi mai, whose descendants were the major cultivars planted in the southwestern winter wheat zone and the northwestern spring wheat zone.

Either directly planted or as parents used in breeding, Italian cultivars have played an important role in China's wheat production. Many cultivars originating in Italy were well adapted to the southern winter wheat zone and some other areas. Ardito, Mentana, and Villa Glori resulted from the famous work of Strampelli (about 1930), in which he crossed Wihelmina with the early maturing Italian landrace Rieti, and then top-crossed the F 1 with Akagomughi, a short-strawed Japanese variety.¹³

Reiti was resistant to disease and had good grain quality. Wilhelmina, the progeny of a backcross of the Dutch landrace Zeeuwse Witte to one of the earliest English cultivars, Squarehead, was high-yielding. Ardito (Ailiduo, also named Zhongda 2509) was introduced very early in China and was planted in Yunnan, Guizhou, Sichuan, Fujian, Anhui, and Jiangsu Provinces. Ardito was short, daylight-insensitive, and highly resistant to stripe rust and loose smut. Villa Glori (Zhongnong 28), introduced in the late 1930s and grown in Sichuan, Guizhou, and Yunnan Provinces, was also daylight-insensitive and highly resistant to stripe rust and loose smut. Mentana (Nanda 2419) was planted throughout the country after 1949 (except in the northeastern spring wheat zone) and was still grown in 1983.

The major Chinese progeny of these early Italian-improved wheats include Yaanzao and Zhuyeqing (from Ardito); Xinong 6028 and Shannong 205 (from Villa Glori); and Niexiang 5, Xuzhou 14, and Emai 6 (from Mentana). Each of the introductions noted aboveand some of the Italian cultivars introduced in the period from 1950 through 1970 (mentioned below) were planted directly, and some of them occupied very large areas.

Before 1949, the U.S. spring wheat cultivars CI 12203 (Gansu 96) and Merit were extended in China's spring wheat production zones. Another U.S. spring wheat, Pilot (Bailuotou), was extended in Heilongjiang Province in the 1950s. A series of Minnesota spring wheats (Songhuajiang 2, 3, 4, and 5) were extended in Heilongjiang, Jilin, and Inner Mongolia Provinces in the 1950s. All of the U.S. spring wheat introductions played an important role in the control of stem rust, and their progeny include Dongnong 101, Keqiang, Kezhuang, Liaochun 1, and Liaochun 2. Pilot, for example, was a selection from Hope (Zeven and Zeven -Hissink 1976) and likely carried the Sr2 complex for stem rust resistance.

Important U.S. winter wheats which were probably introduced before 1949 but were extended during the 1950s include Early Premium (Zaoyang mai), Triumph (Shengli mai), and Cheyenne/Early Blackhull (Qianjiao mai) . Widely grown descendants of Early Premium include Beijing 8, Dongfanghong 3, Jinan 2, Jinan 4, Jinan 9, Shijiangzhuang 54, Changle 5, Xuzhou 14, and their derivatives Beijing 10, Nongda 139, and 12057. Major cultivars descended from Triumph include Nongda 183, Nongda 311, Huabei 187, and Shijiangzhuang 407. Cheyenne and Blackhull were selections from winter wheats brought to the Kansas Experiment Station from the Crimea and were probably selections from (or are related to) Turkey, the major progenitor of all U.S. winter wheats (Flora 1988; Zeven and Zeven-Hissink 1976). Triumph was a hard red winter wheat from Oklahoma; it was also a farmer's selection.¹⁴

Cultivars from Italy and the U.S. also played an important role in China's wheat breeding programs from 1950 through 1970. Chile and Eastern Europe became major sources of breeding material during this period as well. After 1949, many of these lines were introduced through the FSU and Eastern European socialist countries. Tevere (Jieli), Giuliari (Aiganhong), and Funo (Afu) were major Italian improved wheats descended from or related to Ardito (Lupton 1987); Giuliari is a descendant of Tevere. All three were introduced in the 1950s and extended widely in China. All were relatively short, rust resistant, and daylight-insensitive.

The important Chinese selections from (and progeny of) Funo include Boai 7023, Wumai 1, Yangmai 1, Yangmai 2, Yangmai 3, Sichuanyouyimai, Sumai 1, and Sumai 3. The Italian cultivar Abbondanza (Abo) was extended in most of China's wheat zones; introduced in the 1950s, Abbondanza descended from Mentana and Villa Glori (Zeven and Hissink-Zeven 1976). Abbondanza's Chinese progeny include Taishan 4, Ganmai 8, Doudi 1, and Tianxuan 15. St 1472/506 (Zhengyin 1, originally from Italy) was extended in Gansu, Henan, and Jiangsu provinces in 1960s, and its descendant Ningmai 3 was widely grown.

Orofen (Ourou) was an important Chilean introduction that had wide adaptation in China. Released in Chile in 1958, it was introduced to China through Albania. In the 1950s, it was extended in the northern spring wheat zone, the Xingjiang winter and spring wheat zone, the southwestern winter wheat zone, and the southern winter wheat zone. In the 1960s, Orofen was used as a parent in breeding a number of major cultivars, including Taishan 1 and Jinmai 2148; the winter wheat cultivars 12057, Xuzhou 17, Zhongshan 6, and Fengmai 13; and the spring wheat cultivars Xinshuguang 1, Jinghong 5, Qingchun 5, and Jinchun 2. Orofen is also a descendant of Mentana (Zeven and Hissink -Zeven 1976), with Mexican wheat parentage through Yaqui 48, one of the earliest wheats bred by Norman Borlaug. Orofen carries Hope resistance to stem rust inherited through Thatcher, as well as other rust resistance complexes inherited through Frontana.

In general, FSU introductions did not adapt well to Chinese growing conditions. Some were used as parents in breeding lines for the northern winter wheat zone because of certain desirable characteristics (e.g., big spike, big kernel, drought tolerance), and some adapted well in Xinjiang and Ganshu Provinces (including Wukelan 0246, new Wukelan 83, Aodesa 3, Aodesa 16, and Xiaoe 186). Sulian Zaoshu 1, of FSU origin, is a parent for a number of important cultivars, including Xuzhou 15, Taishan 1, and Beijing 10.

With the improvement in Chinese foreign relations during the 1970s, scientific exchange increased. Since the early 1970s, 1B/1R derivativessuch as Lovrin 10 (Romania), Kavkaz, and Neuzuchthave been used in breeding as sources of rust resistance. The Mexican (CIMMYT) wheats Yecora F70, Alondra "S," Veery, and Tanori F71 were introduced and used in breeding during this period. According to Dalrymple (1986), the use of Mexican (CIMMYT) semi-dwarf wheats in direct sowing and in the breeding program began in China during the 1970s, when large quantities of CIMMYT seeds (of varieties Potam, Tanori, Saric, Inia, and Jori) were purchased and planted in the southern and northeastern provinces. Many of these varieties sprouted before harvest, and others were susceptible to scab and stripe rust, which are present in China but not in the irrigated wheat -growing zone of northwestern Mexico. The varieties were later-maturing than indigenous varieties, less drought tolerant, and when sown in the fall, lacked cold tolerance. Chinese breeders crossed the CIMMYT materials with their own lines, and reported progeny from the crosses included winter and spring wheats extended in southwestern and southern China (Zones IV and V), which are relatively minor wheat-producing zones.

Since the early Green Revolution wheat varieties, the ancestral pool of the most popular CIMMYT lines has broadened, and the breeding strategy of pyramiding multiple sources of resistance genes from diverse genetic backgrounds has improved the prospects for more durable rust resistance (Singh and Rajaram 1995).¹⁵ Gradually, CIMMYT materials appear to be playing a more important role in the Chinese breeding program.

During the 1980s and 1990s, with the continuation of economic and political reforms in China, germplasm exchange has become less a matter of diplomatic affairs and more a routine scientific activity. Established in 1978, the Chinese Plant Germplasm Institute began a new stage of germplasm collection and research: it is in charge of introducing cultivars and has established a system of introduction, quarantine, preservation, and germplasm utilization. In recent years, approximately 4000 accessions of common wheat cultivars have been introduced from more than 30 countries, including Yugoslavia, England, France, Romania, Argentina, and the U.S.

Semi-dwarf materials
Since much wheat in China is grown under irrigated conditions,¹⁶ the development of semi-dwarf cultivars has long attracted wheat breeders' attention. Chinese wheat scientists began to breed for short stature in the 1950s. In 1957, wheat breeders in Shaanxi Province crossed Suweon 86 with Xinong 6028 and other cultivars to obtain the first group of dwarf and semi-dwarf cultivars in China. These could not be directly sown in farmers' fields because of their poor plant shape, small spikelets, rust susceptibility, and early withering. As parents, they were used extensively in breeding programs throughout the country. Since 1970s, a large number of semi-dwarf cultivars with high yield potential have been extended; these include Nongda 139, Beijing 10, Taishan 1, Taishan 4, Fan 6, Boai 7023, Jinan 13, Lumai 14, Lumai 15, Ningmai 3, Bainong 3217, and Mianyang 11.

Semi-dwarf cultivars now cover most of the winter wheat areas in China. Among varieties actually cultivated, those with plant heights of 70-90 cm are classified as semi-dwarf, although most of these varieties range from 80 to 90 cm. Varieties shorter than 70 cm are classified as dwarf.¹⁷

Table 17 shows the major parents of 170 Chinese semi-dwarf cultivars, and Table 18 shows the major parents of 70 dwarf accessions, according to the Chinese Plant Germplasm Institute (1982). Examination of Tables 17 and 18 shows that, of the nine major parents, at least four are Italian or Chilean cultivars descended from Akagomughi, the Japanese short-strawed variety that carries the Rht8 and Rht9 dwarfing genes. According to evidence reported in Dalrymple (1986), Abbondanza (descended from Mentanasee Section 6) was considered a semi-tall in China, and Ardito was shorter. As noted in Section 6, Triumph was relatively short among U.S. cultivars. Early Premium does not appear to have been a major parent of Chinese dwarf cultivars.

Table 17. Major parents of 170 Chinese semi-dwarf accessions (70-80 cm)^a

Source: Institute of Crop Germplasm Resources (1982).
^a Varieties used in semi-dwarf breeding must meet a higher standard (i.e., 70-80 cm as opposed to 70-90 cm for the category as a whole).

Table 18. Major parents of 70 Chinese dwarf accessions (shorter than 70 cm)

Source: Institute of Crop Germplasm Resources (1982).

The two Chinese-bred major parents found in Tables 17 and 18 are Xiannong 39 and Xinong 6028. Xiannong 39 was the first dwarf cultivar bred in China, from Xinong 6028 and Suweon 86. Suweon 86 is a sister of Suweon 85 and a relative of Norin 10, the source of the Rht1 and Rht2 dwarfing genes through the landrace Daruma (which originated in Japan or Korea). Norin 10 is one of the parents of the CIMMYT semi-dwarf wheats (Dalrymple 1986). Xinong 6028's parents are Jinyang 60 and Villa Glori (Italy), the latter having descended from Akagomughi. Jinyang 60, also named Xibei 60, is a landrace selection from Shaanxi Province; it is not a dwarf plant. Tables 17 and 18 thus suggest that most of the dwarf genes in Chinese cultivars are derived from foreign germplasm.

In addition to several of the foreign sources of dwarfing genes reported above, Jia has reported the importance of Hui Xian Hong and You Bao mai. You Bao is an improved cultivar from Shandong Province. Youzi mai and Baodasanbaipao are believed to be its parents. However, test results have indicated that neither of these parents contributed You Bao mai's dwarfing genes (Jia 1992). The origin of Hui Xian Hong is unclear. It was reported to be a landrace from Hui County, Henan Province, or an introduction from Japan, resembling Norin 14, a relative of Norin 10 (Dalrymple 1986; Jia 1992). Another more recent domestic source of dwarfism has been identified as a natural mutant of either Aiganzao (a Chinese line from the cross of Suweon 86 and Villa Glori) or Abbondanza. With further selection and breeding, Aibian 1 was obtained from the mutant. Aibian 1 is only 24- to 30-cm tall, and with stable heredity, it has been used and studied in many breeding programs.

¹³ Ardito and Mentana have been of great importance in wheat breeding not only in China and throughout the Mediterranean region, but also in South America and the Former Soviet Union (Lupton 1987).
¹⁴ Blackhull was one of the top five wheat varieties grown in the U.S. from the 1920s through the mid-1940s, and Cheyenne was planted on over 3 million hectares in the U.S. from 1944 to 1974. Triumph was one of the top five wheat varieties grown in the U.S. from the 1950s and 1960s. Triumph had a key characteristic that was not exploited by U.S. wheat breeders until the 1940s: it was relatively short (Dalrymple 1988).
¹⁵ Evidence on CIMMYT wheat varieties is reported in Smale (1995) and Smale et al. (forthcoming).
¹⁶ According to FAO Agrostat data for the People's Republic of China, 52% of cultivated area was irrigated in 1993. CIMMYT (1989) estimated that 31% of the wheat area was irrigated in the mid-1980s, with an 8% growth rate from the 1961-1965 period to the 1981-1985 period.
¹⁷ The formal classification of breeding lines is more restrictive. According to Chinese Plant Germplasm Institute (1982), of 2,391 accessions bred from the 1950s to the 1980s, 170 (7%) are 70-80 cm tall (semi-dwarf), and 70 (3%) are shorter than 70 cm (dwarf).