Irgc Irpb and Inger Impacts on Numbers of Released Varieties

The data for routes suggest a substantial impact for IRRI programmes. A considerable number of borrowed varieties, parents, grandparents and ancestors from IRRI attests to the impact of the IRRI plant breeding programme, though not to its recent contribution. Flows through INGER also attest to its impact, although at least some of the INGER flows are substitutes for other flows. IRRI's germplasm collection has contributed to the flows by supplying genetic material

Table 13.4. Routes of varietal release: descriptive statistics.

Average no. of landraces

Table 13.4. Routes of varietal release: descriptive statistics.

Average no. of landraces

Average

no.

independent

of landraces

of IRRI

Average n

Per cent

of landraces

No. of

Per cent of

Total

of

Pre-

Post-

Pre-

Post-

rare trait in

Route

varieties

varieties

area

area

1976

1976

1976

1976

>5.0

IRRI/INGER

146

8.5

5177

13.3

n.a.

13.2

n.a.

0.0

12.55

IRRI/NO INGER

148

8.7

3959

10.2

5.4

12.4

0.0

0.0

7.66

OTHER/INGER

37

2.2

411

1.1

n.a.

4.2

n.a.

2.1

3.35

OTHER/NO INGER

59

3.5

2954

7.6

4.4

5.2

2.5

1.6

4.14

IRRI PARENT/INGER

214

12.5

6570

16.9

n.a.

10.4

n.a.

1.2

9.55

IRRI PARENT/NO INGER

313

18.3

5589

14.4

5.6

9.5

1.7

1.4

6.53

OTHER PARENT/INGER

208

12.2

4283

11.0

n.a.

2.9

n.a.

2.5

1.52

OTHER PARENT/NO INGER

151

8.8

3228

8.3

3.4

4.8

3.4

3.8

2.68

IRRI GPARENT/INGER

14

0.8

670

1.7

0.0

7.2

0.0

3.0

6.00

IRRI GPARENT/NO INGER

94

5.5

1436

3.7

7.4

10.7

4.6

3.6

8.93

OTHER GPARENT/INGER

0

0.0

0

0.0

0.0

0.0

0.0

0.0

0.00

OTHER GPARENT/NO INGER

180

10.5

1482

3.8

4.4

4.1

4.3

3.8

2.04

PURE NATIONAL

145

8.5

3121

8.0

3.2

2.6

2.7

2.2

1.10

co en to plant breeders at IRRI and in national programmes. Some of this material flows through INGER as well.

In order to address the question of impact in a statistically sound manner, a model that takes national choices into account is required. Variables measuring the impacts on investments in IRGC, IRPB and INGER are required.

Table 13.5 provides a summary of the variables defined for this analysis. These are defined for 15 countries (or groups of countries) for the 1965-1990 period. The key endogenous variables to be 'explained' are R1-R9, the annual varietal releases by route. This set of varieties by route is 'jointly' determined by a set of explanatory variables. In addition, the number of landraces and the number of international and national rare trait materials are also endogenous variables.

The explanatory variables include variables measuring IRGC, IRPB and INGER activities, national demand and national plant breeding activities. Of these, the most complicated is the measure of INGER activities, NING, the number of nurseries in a country. Since this is chosen by the country, it cannot be treated as an exogenous or predetermined variable. It must be modeled as simultaneously determined along with the other endogenous variables. The variables measuring IRGC and IRPB, on the other hand, can be considered to be predetermined and thus exogenous to the national level variables. IRGC, the cumulated number of catalogued IRGC accessions (with passport data), can be

Table 13.5. Variables: IRGC, IRPB, INGER impacts on flows of genetic resources.

I. Endogenous variables measured at the national level

NING The number of INGER nurseries in the country in each year

R1-R8, R13 Flows of released varieties by year by route

II. Predetermined variables: IRRI

POOLR Size of total landrace pool

POOLRI Size of IRRI origin landrace pool

ENTRIES The number of IRRI materials placed in INGER

III. Predetermined variables: national level

CNLR Cumulated landraces of national origin in released varieties

CILR Cumulated landraces of IRRI origin in released varieties by year

IV. Exogenous variables: international level

IRGC Cumulated number of IRGC occasions catalogued with identifiers by year

V. Exogenous variables: national level

OING Number of INGER nurseries in other countries

AREA Land area planted to rice

Country dummy variables

Time dummies (1975-1980), (1981-1985), (1986-1990)

considered to be a determinant of the number of INGER nurseries undertaken in a participant country. IRGC also should have some effect on the rare trait contents. It can also be considered to contribute to the index of IRPB activities, which is measured by the cumulative size of the internationally contributed landrace pool, POOLRI, and to the size of the total landrace pool, POOLR.

Other exogenous variables include the cumulated landraces, both international and national, which are measures of national plant breeding activity. In addition the area planted to rice in a country should be governing genetic resource flows because it reflects demand.

Table 13.6 reports coefficient estimates and 't values from the third stage of a three-stage least squares (3SLS) estimate of the system of ten equations. The intercept and country dummy and time dummy variables coefficients are not reported since they do not generally enter into the policy implications of the results.

The first equation is the equation determining the number of INGER nurseries that the host country chooses. The nurseries have expanded over time and the time dummies reflect this expansion. The rice area variable also explains why countries add more INGER nurseries. We also find that countries respond positively to their neighbours' decisions to conduct INGER nurseries and, most important, that as the catalogued accessions in IRGC expands, the number of INGER nurseries expands. INGER nurseries do not respond to the number of materials placed in trials by IRRI and have actually declined as the total landrace pool has expanded, given the response to IRGC. Thus we find a number of factors influencing the number of INGER nurseries placed in different countries. The 3SLS model treats this number as endogenously determined in the nine route or pathway equations.

As noted earlier, the 'model' underlying the Table 13.6 estimates is one in which the 'flow' of varietal releases through each route or pathway responds to four governing variables in addition to rice area, country and time effects. Two of these variables measure international plant breeding activities (CILR and POOLRI), one measures national plant breeding activities (CNLR), and the fourth, NING, is the outcome of both international (IRGC) and national activities. We expect each of these activities to have different impacts on each flow. In particular, the introduction of INGER is expected to increase the likelihood that a released variety has passed through INGER. We are, however, interested in the total impact, i.e. the sum of the flow impacts, because this tells us whether the activity caused an expansion in the total number of varieties released.

We note first that the AREA variable, while a strong determinant of the number of INGER trials in a country, is not a significant determinant of flows. This is consistent with the interpretation that plant breeding activities (not simply the sizes of countries) govern releases.

Now consider the impact of the variables indexing national and international plant breeding activities. The effort of national plant breeding programmes is indexed by the cumulated stock of landraces and ancestral material embodied in varietal releases by each national programme (CNLR). This

Table 13.6. Estimates of INGER, IRGC, IRPB and NPB impacts 3SLS estimates of ten equation system.

co co

Independent variables

Dependent variable OING IRGC ENTRIES POOLR NING CNLR CILR POOLRI AREA

NING

NING

0.00037

-0.0034

0.0021

0.00013

0.0001

IRRI/INGER

(.16)

(2.57)

(4.42)

(0.05)

(1.09)

-0.0078

0.0013

-0.0008

0.00628

0.0002

IRRI/NO INGER

(3.16)

(1.00)

(1.70)

(2.38)

(2.38)

R3

0.0010

0.0002

0.0006

0.00036

-0.00003

OTHER/INGER

(0.74)

(0.30)

(0.57)

(0.24)

(0.93)

R4

-0.0002

-0.0001

0.0001

0.00389

-0.00007

OTHER/NO INGER

(0.13)

(0.09)

(0.20)

(2.89)

(1.44)

R5

0.0036

0.0054

0.0010

-0.00416

-0.00004

IRRI PARENT/INGER

(1.05)

(2.89)

(1.47)

(1.10)

(0.58)

R6

0.0053

0.0036

-0.0032

0.0254

-0.00000

IRRI PARENT/NO INGER

(0.89)

(1.13)

(2.69)

(3.86)

(0.00)

R7

0.0087

0.0040

-0.0002

0.00062

-0.0004

OTHER PARENT/INGER

(1.72)

(1.43)

(0.22)

(0.11)

(1.82)

R8

0.0121

-0.00068

-0.0005

0.0124

-0.00051

OTHER PARENT/NO INGER

(3.56)

(0.35)

(0.92)

(3.42)

(3.86)

R13

0.0065

0.0068

0.0010

0.00015

-0.00006

NATIONAL

(1.25)

(2.38)

(1.00)

(0.03)

(2.21)

Sum of coefficients

0.0295

0.0173

-0.0003

0.0451

F test on sum

4.75

5.26

0.014

8.35

Prob. > F

0.037

0.021

0.903

0.004

variable has generally positive impacts on most routes and a positive and statistically significant total impact. Not surprisingly, successful national breeding programmes cause more varietal releases.

The two variables measuring the IRRI plant breeding programme, CILR and POOLRI, clearly indicate that it is the size of the IRRI origin landrace pool that is important and not the cumulative stock. In other words, what seems to be important is the introduction of new landrace material into the pool, not the replication of those landraces which are largely the contribution of national programmes. Each landrace added to the pool by IRRI contributes 0.045 varieties annually in each country as indicated by the statistically significant sum of the coefficients.

Now consider the INGER impact. The expansion of INGER diverted varietal flows away from NO INGER routes (R2 and R4) to INGER routes (though this diversion was not highly significant). For parental materials, INGER has a positive impact on all routes including stimulus of NO INGER routes (R6 and R8). This suggests that the INGER nurseries stimulated more international search for genetic resources. It also reflects the fact that INGER nurseries actually include parent and grandparent cultivars that were not initially introduced through INGER.

F tests tell us that NING has a significant positive impact on the total flow of released varieties. The coefficient 0.0295 indicates that one additional INGER nursery is associated with 0.0295 additional released varieties. Thus the addition of 34 nurseries (a nursery is counted in each location in each year) adds one released variety. The implication for ending the INGER programme (i.e. stopping the 900-1000 nurseries each year in recent years) is that this would reduce the recent annual flow of released varieties from 80 per year to around 60 per year. This indicates that INGER has added to the production of released varieties by roughly 25%. This is a large impact.

Each landrace added from IRRI sources causes approximately 0.68 added varieties to be released in each future year. (This coefficient is based on replication in 15 countries.)

IRGC also has an impact on released varieties because it induces added INGER nurseries. The addition of one accession to IRGC causes (0.000875 X 15) = 0.0013 INGER nurseries. This, in turn, means that (0.0295 X 0.0013 X 15) = 0.0058 more varieties are produced. Thus adding 1000 accessions to IRGC causes 5.8 added released varieties in each future year.

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