Agriculture Reference
In-Depth Information
TABLE 3:
Cont.
Farmer
Criteria of selection
Variety se-
lected
Significant changes compared to original
version
“Alwaro”
Longer petioles
Longer leaves
More « yellow » and « greener » leaves
(chromameter)
More erected leaves
More flowering on May 22 and 29
More flowering for all the dates of
observation
leaf blade attitude, leaf blade blistering and intensity of green, shape of
apex and thickness) after pooling the data of the three replicates. For both
ANOVA and Chi square tests, the tests were performed with functions
“aov” and “fisher.test” using R software [16] with a significance thresh-
old of 5%. For bolting and flowering index, we transformed the index in
number of plants bolted or flowered at a given date. For this purpose, we
multiplied the percentage in the middle of the range of the index by the
basic number of plants per plot (32)—we applied 12.5% for index 1, 50%
for index 2 and 87.5% for index 3. We applied chi square tests on the new
count data. However, in Table 5, for these traits, means of the values in the
3 replicates are given in the 0 to 3 scale.
We performed an ascending hierarchical classifi cation on the variety
x version means for all traits except bolting and fl owering indexes in or-
der to assess multi-trait changes of varieties. Data were standardized to a
mean of zero and variance of one prior to the analysis, and the Euclidian
distance and Ward agglomeration criterion (Ward's minimum variance)
were used (function « hclust » in the R freeware was used). Ascending
hierarchical classifi cation is a multivariate analysis that leads to groupings
of the most similar variety x version combinations. However, one must
keep in mind for this multivariate analysis that results are dependent on
the choice of distance among individuals and agglomeration method. For
the latter, simulation studies have shown that there is not one best choice
