ABSTRACT

Five field experiments were conducted in 2004 and 2005 cropping seasons at Obubra

to study the effects of plant spacing and sowing date on the growth and yield of

sesame; to evaluate the yield of sesame varieties intercropped with maize; to ascertain

the most suitable time to introduce component crops and the effect of NPK (15:15:15)

fertilizer on sesame/soybean intercropping; and to determine the fertilizer N, P. and K

requirements of sesame in the forest belt of southeastern Nigeria. The experiment on

plant spacing and sowing date was laid out as a split plot in randomized complete

block design. The experimental design for the maize/sesame intercrop studies was a

randomized complete block design (RCBD), while the experiment on time of

introducing component crops and NPK (15:15:15) fertilizer on soybean/sesame

mixtures was laid out as a factorial in randomized complete block design. The

experiments on the fertilizer N and P, and N and K requirements of sesame were laid

out as factorial in randomized complete block design (RCBD). For each of the

experiments there were three replicates. Results showed that wider spacing resulted

in significantly higher number of capsules/plant and number of seeds per capsule

while closer spacing gave higher seed yield. The best spacing for sesame seed yield

was 30cm x 10cm although 30cm x 15cm can also be adopted with similar results.

Sowing sesame in late July resulted in significant increases in plant height and seed

yield. Sesame and maize or soybean can be successfully intercropped for high seed

yield from component crops, maize should be intercropped with sesame 03L variety.

Planting sesame simultaneously or same day with soybean resulted in more

satisfactory yields of the component crops relative to other planting schedules, while

the application of 150 kg/ha NPK (15:15:15) fertilizer to the mixture resulted in the

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highest seed yield, on average. The yield advantages associated with planting

soybean 4 and 2 weeks before, same day with, 2 and 4 weeks after sesame were 0, 25,

44, 12 and 83%, respectively. On the other hand, the yield advantages accrued to

intercropping at 0, 50, 100 and 150 kg/ha N.P.K fertilizer rates were 109, 27, 8 and

11%, respectively. Combined application of 50 kg N/ha and 60 kg P205/ha as well as

50 kg N/ha and 45 kg }(20/ha or 75 kg N/ha and 15 kg K20/ha gave the optimum

sesame seed yield under the condition of the experiment.