Table 1. Various seed-management rates for cassava in Cauca, Colombia.¹ .

	Type of seed
	Landraces	Improved	Total
A. Replacement by elevation (N = 655)
High	0.33	0.34	0.33
Intermediate	0.15	0.33	0.19
Low	0.21	0.38	0.28
Total	0.25	0.35	0.28
G elevation effect	17.4* (4 df)
G type effect	12.0 *(3 df)
B. Diffusion by origin2 (N = 165)
Local	0.78	0.65	0.75
Introduced	0.72	0.88	0.79
Total	0.77	0.72	0.76
G origin effect	1.7 (2 df)
G type effect	1.8 (2 df)
G complete independence	1.9 (4 df)
C. Introduction by elevation (N = 170)
High	0.12	0.27	0.15
Intermediate	0.26	0.79	0.46
Low	0.14	0.13	0.13
Total	0.15	0.35	0.21
G elevation effect	19.4* (4 df)
G type effect	11.9* (3 df)
D. Mixing by origin (N = 165)
Local	0.44	0.32	0.41
Introduced	0.61	0.39	0.50
Total	0.47	0.35	0.43
G origin effect	1.0 (2 df)
G type effect	1.6 (2 df)
G complete independence	2.1 (4 df)

Significance at the 0.05 level is indicated by *.

1. Expressed as a ratio (varying between 0 and 1), replacement rates imply that seed is not saved across cycles; diffusion rates entail the exchange of saved seed; introduction rates mean that seed is brought into a locality.

2. Seed is “local” if acquired from neighbors and “introduced” if acquired in another locality.