3.4 RESULTS
3.4.6 Pods per plant
Significant interactions were measured between the cultivars and seasons for number of pods plant-1 (Table 3.8). In the 2012/13 season, Lightning produced significantly more pods plant-1 at all seeding rates than AGS 353 and AGS 354, between which no significant difference was measured (Figure 3.16). In the 2013/14 season, Lightning produced significantly more pods plant-1 than AGS 353 and AGS 354 at 50 000 and 75 000 seeds ha-1, but from 100 000 to 250 000 seeds ha-1, the differences were non-significant (Figure 3.17). AGS 292 had significantly fewer pods plant-1 from 50 000 to 200 000 seeds ha-1 than the other three cultivars. In the 2012/13 season, AGS 353 and AGS 354 produced a similar number of pods plant-1 at all seeding rates. However, in the 2013/14 season AGS 353 produced significantly more pods plant-1 than AGS 354 at seeding rates from 75 000 seeds ha-1 and above. This was possibly due to the lower plant population of AGS 353 at those seeding rates. In both seasons, the number of pods plant-1 decreased significantly as seeding rate increased (Figures 3.16 and 3.17).
Significant positive correlations were measured between the number of pods plant-1 and plant height, number of branches plant-1, percentage export marketable pods, number of pods ha-1 and seed yield, whilst significant negative correlations were measured with plant population ha-1 and 100-seed mass (Table 3.15).
89 TABLE 3.8 ANOVA table of number of pods plant-1 for the various cultivars and seeding rates
for two trials
Source of variation F value P value LSD (P<0.05) CV % 2012/13 season
Cultivar 179.97 ** 5.67 -
Seeding rate 73.84 ** 8.02 -
Cultivar x seeding rate 5.17 ** 13.88 12.4
2013/14 season
Cultivar 109.25 ** 6.66 -
Seeding rate 77.00 ** 8.16 -
Cultivar x seeding rate 8.16 ** 16.32 16.5
0 50 100 150 200
50 75 100 150 200 250
Pods plant-1
Seeding rate (seeds ha-1x 1000)
AGS 353 AGS 354 Lightning
a
b c
cd efg fg
c-e;c-f e-g; g gh;g-i h-j;ij jk;jk k;k
FIGURE 3.16 Number of pods plant-1 for three cultivars at six seeding rates in the 2012/13 season
0 50 100 150 200
50 75 100 150 200 250
Pods plant-1
Seeding rate (seeds ha-1x 1000)
AGS 353 AGS 354 Lightning AGS 292
j-m k-m lm lm m m
a b; c; de
cd; c-e; e-g
b;b d-e;e-h;h-j f-i; i-k;i-l j-m
lm g-j
FIGURE 3.17 Number of pods plant-1 for four cultivars at six seeding rates in the 2013/14 season
90 3.4.7 Export marketable pods*
No significant interaction for export marketable pods was measured between the cultivars and seeding rates in the 2012/13 season (Table 3.10). Lightning had a significantly lower mean percentage export marketable pods than AGS 353 and AGS 354 (Figure 3.18). At 200 000 and 250 000 seeds ha-1 significantly lower percentages of export marketable pods were measured than from 50 000 to 150 000 seeds ha-1 (Figure 3.19).
A significant interaction for export marketable pods was measured between the cultivars and seeding rates in the 2013/14 season (Table 3.10). At seeding rates from 50 000 to 100 000 seeds ha-1, AGS 292 had significantly lower percentages of export marketable pods than the other cultivars (Figure 3.20). At 150 000 seeds ha-1 AGS 353 had a significantly higher percentage of export marketable pods than the other cultivars, whilst at 200 000 and 250 000 seeds ha-1 AGS 353 and Lightning had significantly higher percentages of export marketable pods ha-1 than AGS 354 and AGS 292.
Significant positive correlations were measured between percentage export marketable pods and plant height, total pods with seeds plant-1 and seed yield (Table 3.15). A significant negative correlation was measured between percentage export marketable pods and plant population.
TABLE 3.10 ANOVA table of percentage export marketable pods for the various cultivars at the various seeding rates for two trials
Source of variation F value P value LSD (P<0.05) CV % 2012/13 season
Cultivar 4.44 * 2.05 -
Seeding rate 4.81 ** 2.90 -
Cultivar x seeding rate 1.55 NS 5.02 4.2
2013/14 season
Cultivar 21.49 ** 2.29 -
Seeding rate 2.57 * 2.81 -
Cultivar x seeding rate 2.53 * 5.61 4.5
*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.
91 FIGURE 3.18 Percentage export marketable pods for the three cultivars in the 2012/13 season
FIGURE 3.19 Mean percentage export marketable pods of the three cultivars at the various seeding rates in the 2012/13 season
50 60 70 80 90
50 75 100 150 200 250
Export marketable pods (%)
Seeding rate (seeds ha-1x 1000)
AGS 353 AGS 354 Lightning AGS 292
j
ij e-h f-h; c-h b-h; c-h gh;h-j
ab a-d;a-d
ab;a-e a-f
a-c;a-c;a-d ab;b-h a;a-e
a-g;d-h
j
FIGURE 3.20 Percentage export marketable pods of four cultivars at the various seeding rates in the 2013/14 season
92 3.4.8 Pods per hectare
A significant interaction was measured for the number of pods ha-1 between the cultivars and seeding rates in the 2012/13 season (Table 3.11). At all seeding rates, Lightning produced significantly more pods ha-1 than AGS 353 and AGS 354, between which no significant differences were measured (Figure 3.21).
No significant interaction was measured for the number of pods ha-1 between the cultivars and seeding rates in the 2013/14 season (Table 3.11). Lightning and AGS 292 produced significantly more and less pods ha-1, respectively, than the other two cultivars (Figure 3.22). In both seasons the number of pods ha-1 increased significantly with increasing seeding rates (Figure 3.3).
Significant positive correlations were measured between the number of pods ha-1 and plant population ha-1, plant height, bottom pod height and the number of branches plant-1, but a significant negative correlation was measured with 100-seed mass (Table 3.15).
TABLE 3.11 ANOVA table of number of pods ha-1 for the various cultivars and various seeding rates for two trials
Source of variation F value P value LSD (P<0.05) CV % 2012/13 season
Cultivar 252.45 ** 475.0 -
Seeding rate 55.35 ** 671.7 -
Cultivar x seeding rate 7.05 ** 1163.5 10.4
2013/14 season
Cultivar 89.90 ** 899.7 -
Seeding rate 7.29 ** 1101.9 -
Cultivar x seeding rate 1.31 NS 2203.7 18.3
93 0
5 10 15 20
50 75 100 150 200 250
Pods ha-1 x 1 000 000
Seeding rate (seeds ha-1x 1000)
AGS 353 AGS 354 Lightning
de
b
de d c b a
j;j ij;h-j hi;h-j f-h; f-h ef;e-g ef;ef
FIGURE 3.21 Number of pods ha-1 for the three cultivars at the various seeding rates in the 2012/13 season
0 5 10 15
AGS 292 AGS 353 AGS 354 Lightning
Pods ha-1 x 1 000 000
Cultivar
b
a c b
FIGURE 3.22 Number of pods ha-1 for the four cultivars in the 2013/14 season
0 2 4 6 8 10
50 75 100 150 200 250
Pods ha-1 x 1 000 000
Seeding rate (seeds ha-1x 1000)
b bc abc a ab
d c
FIGURE 3.23 Mean number of pods ha-1 at the various seeding rates in the 2013/14 season
94 3.4.9 Seed mass
No significant interactions were measured between the cultivars and seeding rates for 100-seed mass in both seasons (Table 3.12). In the 2012/13 season no significant differences in 100-seed mass were measured among the seeding rates. However, in the 2013/14 season significantly higher 100-seed masses were measured at 50 000 and 150 000 seeds ha-1 than at the other four seeding rates (Figure 3.26). Lightning produced significantly lower 100-seed masses than the other three cultivars in both seasons (Figures 3.24 and 3.25).
Significant negative correlations were measured between 100-seed mass and plant population ha-1, plant height, bottom pod height, the number of branches plant-1, the number of pods with seeds plant-1 and the number of pods ha-1 (Table 3.15). No significant correlation was measured between 100-seed mass and seed yield ha-1.
TABLE 3.12 ANOVA table of 100-seed mass for the cultivars and various seeding rates for two trials
Source of variation F value P value LSD (P<0.05) CV % 2012/13 season
Cultivar 70.17 ** 2.05 -
Seeding rate 1.20 NS 2.89 -
Cultivar x seeding rate 0.46 NS 5.01 7.6
2013/14 season
Cultivar 125.47 ** 2.15 -
Seeding rate 7.28 ** 2.63 -
Cultivar x seeding rate 0.91 NS 5.26 7.7
0 10 20 30 40 50
AGS 353 AGS 354 Lightning
100-seed mass (g)
Cultivar
a a
b
FIGURE 3.24 100-seed mass of the three cultivars in the 2012/13 season
95 0
10 20 30 40 50
AGS 292 AGS 353 AGS 354 Lightning
100-seed mass (g)
Cultivar
a a
b a
FIGURE 3.25 100-seed mass of the four cultivars in the 2013/14 season
0 10 20 30 40 50
50 75 100 150 200 250
100-seed mass (g)
Seeding rate (seeds ha-1x 1000)
a b b b a b b
FIGURE 3.26 100-seed mass at various seeding rates in the 2013/14 season