TY - JOUR
T1 - Dinitrogen fixation in Kura clover and birdsfoot trefoil
AU - Seguin, P.
AU - Russelle, M. P.
AU - Sheaffer, Craig C
AU - Ehlke, Nancy Jo J
AU - Graham, P. H.
PY - 2000
Y1 - 2000
N2 - The quantification of symbiotic N2 fixation by legumes is essential to determine their impact on N budgets. Kura clover (Trifolium ambiguum M.B.) and birdsfoot trefoil (Lotus corniculatus L.) are two promising pasture legumes for which such estimates are scarce. Dinitrogen fixation by 2- and 3-yr-old stands of these species was determined at two locations in Minnesota using the 15N isotope dilution method. Species were evaluated for forage and N yields, the percent of N derived from the atmosphere (%Ndfa), and the amount of fixed N2 at each of four harvests. The results for each parameter varied with location, legume species, and harvest, as demonstrated by a three-way interaction among these terms. Across environments, both species produced the greatest amount of forage, total N, and fixed N yields at the first harvest. The yields decreased with successive forage harvests at one location but stabilized at the other. The %Ndfa for Kura clover was stable across harvests and environments. The %Ndfa for birdsfoot trefoil varied during the season, with a peak at the end of the season. The yearly total forage, total N, and fixed N yields of Kura clover were stable across environments, and the total N and fixed N yields were greater than those of birdsfoot trefoil at one location. Overall, Kura clover fixed about 155 kg N ha-1 yr-1, with a %Ndfa of 57; birdsfoot trefoil had amounts of fixed N2 that varied with locations (avg. of 145 kg N ha-1 yr-1), and it obtained about 62% of its herbage N from fixation.
AB - The quantification of symbiotic N2 fixation by legumes is essential to determine their impact on N budgets. Kura clover (Trifolium ambiguum M.B.) and birdsfoot trefoil (Lotus corniculatus L.) are two promising pasture legumes for which such estimates are scarce. Dinitrogen fixation by 2- and 3-yr-old stands of these species was determined at two locations in Minnesota using the 15N isotope dilution method. Species were evaluated for forage and N yields, the percent of N derived from the atmosphere (%Ndfa), and the amount of fixed N2 at each of four harvests. The results for each parameter varied with location, legume species, and harvest, as demonstrated by a three-way interaction among these terms. Across environments, both species produced the greatest amount of forage, total N, and fixed N yields at the first harvest. The yields decreased with successive forage harvests at one location but stabilized at the other. The %Ndfa for Kura clover was stable across harvests and environments. The %Ndfa for birdsfoot trefoil varied during the season, with a peak at the end of the season. The yearly total forage, total N, and fixed N yields of Kura clover were stable across environments, and the total N and fixed N yields were greater than those of birdsfoot trefoil at one location. Overall, Kura clover fixed about 155 kg N ha-1 yr-1, with a %Ndfa of 57; birdsfoot trefoil had amounts of fixed N2 that varied with locations (avg. of 145 kg N ha-1 yr-1), and it obtained about 62% of its herbage N from fixation.
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U2 - 10.2134/agronj2000.9261216x
DO - 10.2134/agronj2000.9261216x
M3 - Article
AN - SCOPUS:0034544952
SN - 0002-1962
VL - 92
SP - 1216
EP - 1220
JO - Agronomy Journal
JF - Agronomy Journal
IS - 6
ER -