150
Fertilizer Use Efficiency
Fertilizer use efficiency (FUE) was calculated by dividing the increased grain yield
due to fertilizer by the amount of fertilizer applied (Kelly et al. 2006). According to
Kelly et al. (2006), the threshold value is 10 kg of grain (millet or sorghum) for each
kg of fertilizer. The FUE was calculated for the combined effect of seed priming and
microdosing and for microdosing alone. The yield difference between “priming +
microdosing” minus “control” was used to calculate the combined effect of priming
and microdosing, whereas the difference between “priming + microdosing” minus
“priming” was used to calculate the effect of microdosing alone.
Analysis of Environmental Conditions on the Response to Seed Priming
and Microdosing
The analysis assessed under which environmental condition seed priming and
microdosing are performing the best. The relative yields between treatments and
control were calculated and plotted against the yield of the control in the plot.
Economic Analysis
A partial gross margin was calculated for each treatment by calculating the difference between the revenue from the grains and the costs. The cost items were inputs
and labor related to seed priming and microdosing. The other labor costs were not
included. Local prices for the grains and input were used.
Cumulative Probability for Gross Margin
A probability analysis was undertaken by utilizing the results from all the sites in
2007 and 2008. For each treatment, the gross margins were arranged in ascending
order to display the probability of reaching a certain gross margin for each treatment.
3 Results and Discussion
3.1 Yield Increase in Sorghum and Millet
Overall, there was a good response to seed priming and microdosing in pearl millet
and sorghum, but sorghum was generally more responsive to priming and microdosing than millet.
Priming was able to increase grain yield in both sorghum and millet (Tables 2
and 3). In sorghum, priming increased yield by 55% in 2006, whereas the response
in sorghum for 2007 and 2008 was up to 19%. For millet, the response to priming
A. Coulibaly and J. B. Aune
Fertilizer Use Efficiency
Fertilizer use efficiency (FUE) was calculated by dividing the increased grain yield
due to fertilizer by the amount of fertilizer applied (Kelly et al. 2006). According to
Kelly et al. (2006), the threshold value is 10 kg of grain (millet or sorghum) for each
kg of fertilizer. The FUE was calculated for the combined effect of seed priming and
microdosing and for microdosing alone. The yield difference between “priming +
microdosing” minus “control” was used to calculate the combined effect of priming
and microdosing, whereas the difference between “priming + microdosing” minus
“priming” was used to calculate the effect of microdosing alone.
Analysis of Environmental Conditions on the Response to Seed Priming
and Microdosing
The analysis assessed under which environmental condition seed priming and
microdosing are performing the best. The relative yields between treatments and
control were calculated and plotted against the yield of the control in the plot.
Economic Analysis
A partial gross margin was calculated for each treatment by calculating the difference between the revenue from the grains and the costs. The cost items were inputs
and labor related to seed priming and microdosing. The other labor costs were not
included. Local prices for the grains and input were used.
Cumulative Probability for Gross Margin
A probability analysis was undertaken by utilizing the results from all the sites in
2007 and 2008. For each treatment, the gross margins were arranged in ascending
order to display the probability of reaching a certain gross margin for each treatment.
3 Results and Discussion
3.1 Yield Increase in Sorghum and Millet
Overall, there was a good response to seed priming and microdosing in pearl millet
and sorghum, but sorghum was generally more responsive to priming and microdosing than millet.
Priming was able to increase grain yield in both sorghum and millet (Tables 2
and 3). In sorghum, priming increased yield by 55% in 2006, whereas the response
in sorghum for 2007 and 2008 was up to 19%. For millet, the response to priming
A. Coulibaly and J. B. Aune