Altitude and source effects on rates of maize seed-lot replacement (1−p) and diffusion (q) in Mexico1.

Significant at the 0.05 level is indicated by **; significance at the 0.10 level is indicated by *. G-tests exclude seed from formal seed systems; masl: meters above sea level.1Expressed as a ratio, rates vary between 0 and 1. Replacement implies that seed is not saved by a farmer across cycles; diffusion entails the exchange of saved seed among farmers.2The terms “local” and “introduced” refer to the location of the immediate source of seed; e.g., seed is local if acquired from neighbors, while seed acquired from farmers in another locality is introduced.3Seed acquired during the current cycle is “new;” seed saved by the farmer from a previous cycle is his/her “own.”