5.4 RESULTS
5.4.7 Residue dry matter yield (Leaves, stems and branches)
5.4.8.1 Seedless pods
A significant interaction was measured for percentage seedless pods between the cultivars and seasons (Table 5.11). AGS 353 had significantly more seedless pods than Lightning in the 2012/13 season, but not in the 2013/14 season (Figure 5.15). Mean percentage seedless pods was significantly higher in the 2012/13 season.
A significant interaction was measured for mean percentage seedless pods among the cultivars and P and K application rates (Table 5.11). Mean percentage seedless pods was significantly lower at 0 kg P ha-1 than at the two higher P application rates and decreased significantly with increasing K application rate (Figure 5.16).
Percentage seedless pods was significantly positively correlated to plant population, but significantly negatively correlated to plant height, bottom pod height, residue DM yield, pods plant-1, percentage export marketable pods, pod and bean DM yield, and shelling percentage (Table 5.18).
167 TABLE 5.11 ANOVA table of percentage seedless pods for the two cultivars at the phosphorus
and potassium application rates in the two seasons
Source of variation F value P value LSD (P<0.05) CV %
Season 88.84 ** 2.637 -
Cultivar 204.76 ** 0.851 -
Season x cultivar 106.23 ** 2.574 -
Phosphorus (P) application rate 11.62 ** 1.432 -
Potassium (K) application rate 12.12 ** 1.849 -
Season x P application rate 0.71 NS 2.746 -
Season x K application rate 1.42 NS 3.124 -
Cultivar x P application rate 0.68 NS 1.754 -
Cultivar x K application rate 0.78 NS 2.265 -
P x K application rates 0.96 NS 3.203 -
Season x P x K application rates 0.57 NS 4.778 -
Season x cultivar x P application rate 0.05 NS 3.034 -
Season x cultivar x K application rate 0.62 NS 3.598 -
Cultivar x P x K application rates 2.18 * 3.923 -
Season x cultivar x P x K application rates 0.82 NS 5.748 21.4
0 5 10 15 20 25
2012/13 2013/14
Seedless pods (%)
Season
AGS 353 Lightning a
b
c c
FIGURE 5.15 Percentage seedless pods for the two cultivars in the two seasons
0 5 10 15 20 25
0 40 80 120 160
Seedless pods (%)
Potassium application rate (kg ha-1)
AGS 353 0 kg/ha P AGS 353 30 kg/ha P AGS 353 60 kg/ha P Lightning 0 kg/ha P Lightning 30 kg/ha P Lightning 60 kg/ha P a;ab;a-d a-c; b-f;f-j c-f;c-e;f-i a-e; d-h;f-h
d-h;e-h;f-j
h-k; j-p;p g; l-p;n-p g-n;i-p;k-p m-p;op;p d-g;d-h;g-n
FIGURE 5.16 Percentage seedless pods for the two cultivars at the three P application rates and five K application rates
168 5.4.8.2 Export marketable pods*
A significant interaction was measured for percentage export marketable pod between the cultivars and seasons (Figure 5.17). Lightning had significantly higher percentages of export marketable pods in both seasons than AGS 353. A significantly higher mean percentage export marketable pods was measured in the 2013/14 season than in the 2012/13 season. Percentage export marketable pods was significantly lower at 0 kg K ha-1 than at the other K application rates, among which no significant differences were measured (Figure 5.18).
Percentage export marketable pods was significantly positively correlated to plant height, bottom pod height, residue DM yield, pods plant-1, pod and bean DM yield and shelling percentage, but significantly negatively correlated to plant population and percentage seedless pods (Table 5.18).
TABLE 5.12 ANOVA table of percentage export marketable pods for the two cultivars at the phosphorus and potassium application rates in the two seasons
Source of variation F value P value LSD (P<0.05) CV %
Season 75.34 ** 1.858 -
Cultivar 271.83 ** 0.946 -
Season x cultivar 25.34 ** 1.858 -
Phosphorus (P) application rate 1.84 NS 1.228 -
Potassium (K) application rate 9.07 ** 1.585 -
Season x P application rate 1.77 NS 2.060 -
Season x K application rate 1.84 NS 2.456 -
Cultivar x P application rate 0.93 NS 1.670 -
Cultivar x K application rate 1.21 NS 2.156 -
P x K application rates 1.92 NS 2.745 -
Season x P x K application rates 1.16 NS 3.980 -
Season x cultivar x P application rate 1.00 NS 2.567 -
Season x cultivar x K application rate 1.56 NS 3.192 -
Cultivar x P x K application rates 1.40 NS 3.734 -
Season x cultivar x P x K application rates 1.29 NS 5.352 4.7
*Export marketable pods are pods containing two or more beans. The length and width of the pods have not been considered, although they are important charcteristics to meet the requirements of the export market.
169
0 20 40 60 80
2012/13 2013/14
Export marketable pods (%)
Season
AGS 353 Lightning
b c a
d
FIGURE 5.17 Percentage export marketable pods of the two cultivars in the two seasons
0 10 20 30 4050 60 70 80
0 40 80 120 160
Export marketable pods (%)
Potassium application rate (kg ha-1)
b a a a a a
FIGURE 5.18 Percentage export marketable pods at the five K application rates 5.4.8.3 Number of pods plant-1
A significant interaction was measured for number of pods plant-1 between the cultivars and seasons (Table 5.13). Lightning produced significantly more pods plant-1 than AGS 353 in both seasons, but had a significantly higher number of pods plant-1 in the 2012/13 season, whilst AGS 353 had a significantly higher number of pods plant-1 in the 2013/14 season (Figure 5.19).
At 60 kg P ha-1, the mean number of pods plant-1 was significantly higher than at 0 and 30 kg P ha-1 (Figure 5.20).
A significant interaction was measured for mean number of pods plant-1 between the cultivars and K application rates (Table 5.13). At 0 kg K ha-1, AGS 353 had a significantly lower number of pods plant-1 than at 120 kg K ha-1, whilst at 40 kg K ha-1, Lightning had significantly fewer pods plant-1 than at 160 kg K ha-1 (Figure 5.21).
170 The number of pods plant-1 was significantly positively correlated to plant height, residue DM yield, percentage export marketable pods, pod and bean DM yield, and shelling percentage, but significantly negatively correlated to percentage seedless pods (Table 5.18).
TABLE 5.13 ANOVA table of number of pods with beans plant-1 for the two cultivars at the phosphorus and potassium application rates for two seasons
Source of variation F value P value LSD (P<0.05) CV %
Season 0.93 NS 1.709 -
Cultivar 995.51 ** 0.524 -
Season x cultivar 139.71 ** 1.669 -
Phosphorus (P) application rate 3.85 * 0.940 -
Potassium (K) application rate 0.84 NS 1.213 -
Season x P application rate 0.36 NS 1.786 -
Season x K application rate 0.97 NS 2.037 -
Cultivar x P application rate 1.22 NS 1.128 -
Cultivar x K application rate 2.96 * 1.456 -
P x K application rates 0.61 NS 2.102 -
Season x P x K application rates 0.44 NS 3.129 -
Season x cultivar x P application rate 1.41 NS 1.954 -
Season x cultivar x K application rate 2.30 NS 2.315 -
Cultivar x P x K application rates 1.69 NS 2.522 -
Season x cultivar x P x K application rates 0.92 NS 3.696 8.7
0 5 10 15 20 25 30
2012/13 2013/14
Pods plant-1
Season
AGS 353 Lightning
a b
c d
FIGURE 5.19 Number of pods plant-1 for the two cultivars in the two seasons
171
0 10 20 30 40
0 30 60
Pods plant-1
Phosphorus application rate (kg ha-1)
b b a
FIGURE 5.20 Number of pods plant-1 at the three P application rates
0 5 10 15 20 25 30
0 40 80 120 160
Pods plant-1
Potassium application rate (kg ha-1)
AGS 353 Lightning
ab b ab ab a
d cd cd c cd
FIGURE 5.21 Number of pods plant-1 for the two cultivars at the five K application rates