Grain Legumes and Green Manures for Soil Fertility in ... - cimmyt

Lablab purpureus, Crotalaria juncea, Tephrosia vogelii)
were planted at the same time as the maize in half
the pots and then two weeks after planting maize in
the others. Sale crops were also irfcluded as a control
treatment. The legumes were thinned to one
plant per pot at two weeks after planting. Compound
D (8N: 14P20s: 7K20) was applied to supply
0.6 g N/maize plant, 1.1 g P20s/maize plant and 0.6
g K20/maize plant; an equivalent of 300 kg/ha of
the fertilizer in the field. Ammonium nitrate (34.5%
N) was applied at 4 and 8 weeks to make up to 0.8
g/pot total N. Plants were given supplementary irrigation
to field capacity as necessary. Maize plant
heights were taken at 4 and 8 weeks, while leaf area,
shoot dry weight and root dry weight were tak~n at
4, 6 and 8 weeks after planting. Striga counts per pot
were recorded at 40 days after planting and weekly
thereafter.
A similar trial was conducted at Mlezu Institute of
Agriculture, also near to Haran~, in a field that had
been artificially infested with S. asiatica the previous
year. Maize was planted to achieve a plant population
density of 37 037 velvet bean and dolichos
plants/ha, 74 064 sunnhemp plants/ha and 10 000
fish bean plants/ha. Compound D was applied as
initial fertilizer at a rate of 300 kg/ha. No topdress
N was applied because of prolonged dry spells. S.
asiatica counts were taken from the four centre rows
every two weeks after planting. Data analysis was
done using GENST AT 5 Release 3.22. Treatment differences
were compared using the least significant
difference (LSD P