NITROGEN ACCUMULATION AND NITROGEN RESIDU ES OF FIELD BEANS (VICIA-FABA L) .3. UTILIZATION AND CONSERVATION OF MINERALIZED NITROGEN AFTER FIELD BEANS BY INTERPLANTING
W. Aufhammer et al., NITROGEN ACCUMULATION AND NITROGEN RESIDU ES OF FIELD BEANS (VICIA-FABA L) .3. UTILIZATION AND CONSERVATION OF MINERALIZED NITROGEN AFTER FIELD BEANS BY INTERPLANTING, Die Bodenkultur, 46(1), 1995, pp. 25-37
Field trials were conducted to test methods of interplanting in order
to conserve and to use mineralized nitrogen during a 6-8 months period
after harvesting field beans. During flowering or at brown ripe stage
of field bean crops winter rape and winter barley were undersown, res
pectively. The goal was to establish reasonable crops by undersowing w
ithout soil preparation, at first to ensure a quick and early uptake o
f mineralized nitrogen and secondly to grow a subsequent crop for grai
n production. Additionally winter rape and winter barley were sown aft
er the harvest of field beans at locally conventional dates and method
s. During a 6-8 months period the N-min-content of the soil (kg NO3-N/
ha, depth 0 to 90 cm) and the N-uptake (kg N/ha) by winter rape and wi
nter barley were measured. At full ripe stage grain yields of winter r
ape and winter barley were measured. Crops undersown during flowering
emerged satisfactorily but suffered from lack of light. Crops undersow
n on the soil surface at brown ripe stage did not emerge under dry con
ditions. On the other hand undersown and fairly well developed crops r
educed N-min-levels to 20 kg N/ha quickly and remarkably earlier as co
mpared to conventionally sown rape or barley crops. Attempts to improv
e the coordination of field bean crops and undersown crops are discuss
sed. Grain yields of undersown winter rape and winter barley crops did
not reach yield levels of conventionally sown crops, but efforts to o
ptimize the lateron growth and yielding of undersown crops are under i
nvestigation.