Assessment of the adoption and utilization of conservation agriculture in wheat growing regions of Australia and Mexico using the agricultural innovation system framework

Abstract

The Conservation Agriculture Appraisal Index (CAAI) is a theoretical framework that was developed as a benchmarking tool to quantify, at the farm level, the concomitant utilization of the conservation agriculture (CA) principles: 1) minimum soil disturbance (MSD), 2) permanent soil cover (PSC), and 3) diversified crop rotations (DCR), plus the additional principle of controlled-traffic (CTF) farming which includes permanent-raise beds on small to medium farms in irrigated systems. The degree of adoption of CA has been widely studied, however estimates are questionable as different units of measurement were used. This prompted the development of CAAI as an integrated scoring system to account for CA adoption by farm area and cropping season.

CAAI was validated on 100 farms in four regions: two in Australia and two in Mexico, to assess the degree of CA adoption. It was found that minimum soil disturbance accounted for most of the variance in CAAI scores. Significant regional differences were found and CA per se was higher in Australia, compared to Mexico where partial and periodic adoption was more prevalent.

The drivers of adoption were then examined by comparing CAAI scores with the use of key inputs such as glyphosate, paraquat, N, P and in water use efficiency (WUE) for wheat. Significantly greater use of glyphosate and paraquat were observed in the two Australian dryland regions with higher CA adoption. There were no statistically significant differences between N and P with CAAI, although greater amounts of these fertilizers were applied in Mexico compared to Australia. Likewise, WUE did not differ significantly with CAAI score but by region.

Finally, using the data of 114 farmers a social network analysis identified that early adopters, agronomists, research, and government institutions are actors that influenced knowledge sharing of CA principles in the studied regions. More heterophilic networks were observed in regions with both summer and winter crops.