Cassava [on-farm research]
1979
In 1979 the technology development within the CIAT Cassava Program was at the critical testing and evaluation stage before release of the 1st technology packages to national extension agencies. The overall structure for this evaluation process had been largely defined and was in process of implementation, with principal focus being put on expanding this system into all major cassava producing countries in Latin America. The International Regional Yield Trials had shown that germplasm selections and 1st hybrids could yield well, but that yield was highly dependent on agroclimatic conditions. The selected line M Col 1684 had shown very broad adaptability giving consistently high yields in Colombia and, in 4 international trials, it gave an av. yield of 33 t/ha while the regional varieties in the same trials yielded only 19 t/ha. Results from farm-level trials were limited and more extensive testing was planned. Initial results showed that the yields of local varieties can be markedly increased by use of CIAT improved cultural practices. The yields of selected varieties highlighted the important interaction between yield and agroclimatic conditions and defined other variety characteristics as being important to farmers. These results emphasized the importance of these trials in the evaluation and testing procedure. The evaluation of new cassava technology was in the ex-ante stage. Definition and characterization of the major production zones was critical to an evaluation of the impact of new cassava technology, as well this would define which of the results from the regional and on-farm trials were most representative and define sites when trials should be located. Methodologies and data gathering services existed making a more thorough analysis of the ex-ante impact of new cassava technology feasible
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