Agriculture Reference
In-Depth Information
TABLE 1:
Examples of families with significant changes among F3 progeny from selected
and non-selected spikes in the F2 generation evaluated at the research station of Le Moulon.
PH
LLSD
GW/Spike
TKW
Family
P-value
Change
P-value
Change
P-value
Change
P-value
Change
24
0.0187
-
0.4038
ns
0.6568
ns
0.0021
+
34
0.0001
+
<.0001
+
0.723
ns
0.0051
+
42
0.0786
+
0.0016
+
0.5407
ns
0.602
ns
60
0.0956
+
0.0442
-
0.6457
ns
0.752
ns
64
<.0001
+
0.0001
+
0.0366
+
0.3011
ns
80
<.0001
+
0.0114
+
0.0158
+
0.0884
+
90
0.5706
ns
0.2792
ns
0.0014
+
0.0005
+
PH = Plant height from the ground to the top of the spike not including the awns; LLSD
= distance between the base of the spike and the flag leaf; SL = length of the spike from
the base to the tip not including the awns; GW/Spike = weight of grain per spike; TKW =
thousand kernel weight; P = values for the difference between selected and non-selected
progeny within each F3 family using ANOVA and Tukeys mcp. The direction of change
from non-selected to selected progeny is given for p < 0:1;
-
non-selected>selected, +non-
selected<selected, ns = p > 0:1
.
11.4 DISCUSSION
11.4.1 SELECTION WITHIN FARMER VARIETIES
Traits such as PH are very easy to see in the field and every farmer chose
plants that were taller than the average for the plot, but that had not lodged.
The majority of organic farmers involved in this network state that they
would like varieties that are vigorous and tolerant of weed pressure early
in the growing season but strong enough not to lodge. In contrast, long
LLSD is a characteristic sought by farmers but did not have a signifi cant
selection differential in most cases. This trait may be more diffi cult to
evaluate in the fi eld or may not be as important as traits such as GW/spike
and PH when farmers are making their selections.
