International Flows of Genetic Resources

Table 13.2 reports measures of international flows of genetic resources associated with the released varieties and the parents of the released varieties. Of the 1709 released varieties, 390 (24%) were the result of a cross made outside the releasing country IRRI was the source for 294 of these varieties. Other national programmes were the source for 96 releases. (Appendix Table 13.A1 provides country details for varieties.)

After IRRI, India was the next largest exporter of varieties, with 28 Indian varieties released elsewhere. India was also a large importer of varieties; 70 of its 643 varieties originated elsewhere, with 53 from IRRI. Sri Lankan varieties were released 11 times in other countries. Twelve Thai varieties were released in Myanmar; Myanmar was one of the largest importers of rice varieties; 43 of its 76 releases were imported varieties, including varieties from Bangladesh, China, India, Indonesia, IRRI, the Philippines, Sri Lanka, Thailand and Vietnam.

In addition to IRRI's direct role as a source of exported varieties, it has served as a conduit through which elite lines have moved from country to country. Even before the establishment of INGER in 1975, IRRI scientists helped to test and disseminate elite lines of rice around the world. This function was formalized with the inauguration of INGER. Through INGER's activities, elite lines and released varieties from national research programmes have been made available for international testing and evaluation. Participating countries have gained access to promising varieties, and in some cases, they have been able to import them directly from the INGER nurseries.

INGER itself keeps a complete and accurate set of data on varietal importing that has occurred through its programmes. INGER has documented more than 300 instances of varieties imported after appearing in INGER trials.8 Our study lacks complete data on varietal releases in participant countries, especially in Africa and Latin America. Nonetheless, for a limited set of countries, this study

Table 13.2. International genetic resource flows by time period.

Pre- 1966- 1971- 1976- 1981- 19861965 1970 1975 1980 1985 1991 Total

I. Released varieties, per cent based on

IRRI cross

3

25

19

22

18

12

17

Other NAR cross

16

7

6

6

6

5

6

Own NAR cross

81

68

75

72

76

83

77

II. Parents of released varieties,

II. Parents of released varieties,

per cent with one or more parents

IRRI cross

0

24

29

33

23

19

24

Other NAR cross

27

25

21

15

18

20

18

Own NAR cross

73

51

50

52

59

61

58

was able to identify nearly 200 instances in which varieties could have been imported through INGER.9 In particular, INGER has played a significant role in disseminating IRRI lines. For varieties developed at IRRI and released by national programmes, INGER was the apparent conduit in half of the cases, all of them in the period, 1976-1991.

Since 1976, INGER has also become the primary channel through which nationally developed varieties have been transferred from one country to another. Since 1976, 37 national programme varieties have been imported through INGER. During the same period, the number of national programme varieties imported through other avenues has diminished from 13 in 1976-1980 to six in 1986-1991. INGER has played an important role in facilitating the transfer of varieties across geographic zones; for instance, both of two Sri Lankan varieties released in Africa came through INGER, and both of two Indian varieties released in Latin America came through INGER.

Perhaps more remarkable than the direct international flows of varieties has been the international flows of parents of the varieties. Nearly three-quarters of the varieties in the data set (1263) have at least one imported parent. Including imported varieties, 810 releases (47%) have at least one parent from IRRI, and 619 (36%) have at least one parent from another national programme (Table 13.2). Excluding imported varieties, more than 500 varieties have at least one parent from IRRI. Excluding both imported varieties and those with IRRI parents, more than 350 released varieties have at least one parent from another national programme. This indicates that the importation of parent materials is taking place across national programmes on a large scale. (Appendix Table 13.A2 reports country details for parents.)10

The extent of international exchange - both of varieties and of parents -implies that a large majority of the varieties in the data set were developed using breeding lines from outside the country of release. In fact, only 145 varieties out of 1709 (8.5%) were developed entirely from own-country parents, grandparents and other ancestors. Most of these were simple varieties with fewer than four ancestors in their pedigree. The extent of this international flow of germplasm is extraordinary: no country in the data set has failed to take advantage of unimproved or improved germplasm from other countries.

National rice improvement programmes have depended to differing extents on IRRI lines as sources of genetic materials (Appendix Tables 13.A1 and 13.A2). Some countries have borrowed many of their released varieties or parent lines from IRRI, while others have used IRRI materials in conjunction with local varieties or other internationally available breeding lines. For example, Vietnam and Pakistan have based their modern varieties almost completely on IRRI lines, but Sri Lanka used a large pool of other breeding lines as sources of germplasm.

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