Research Article

Biological Nitrogen Fixation by Local and Improved Genotypes of Cowpea in Burkina Faso (West Africa): Total Nitrogen Accumulated can be used for Quick Estimation

Table 3

Total N and percentage of N accumulated from atmosphere in shoots of local and improved genotypes of cowpea using total nitrogen difference (TND) and isotopic dilution (ID) methods.

Types and names of cowpea genotypesTotal N accumulatedN derived from atmosphere 
(kg N ha−1)
N derived from atmosphere 
(% of total N)
kg N ha−1Total N DifferenceIsotopic DilutionTotal N DifferenceIsotopic Dilution

Local genotypesGorom local23.08.98.438.737.4
Moussa local30.916.8- 53.7 -
Boussé local40.626.511.665.328.6
Improved Genotypes11K56.942.825.475.244.6
11P77.363.239.481.851.0
Bambey -2135.521.4-60.3-
IAR 7/180-4-5-142.528.411.566.827.1
KVX 414-22-7226.812.78.847.432.8
IT 89KD374-5724.710.610.742.943.3
KN 130.516.410.553.834.4
TVX -323638.624.512.763.532.9
Non-fixing genotypeIC-114.1----
Standard Error5.85.84.28.87.3