YIELD AND LEAF NUTRIENT CONCENTRATIONS OF ARABICA COFFEE DURING THE 2ND PRODUCTION CYCLE AFTER ESTABLISHMENT AS INFLUENCED BY NITROGEN RATES AND PLANT-DENSITY
Jm. Njoroge et Jk. Kimemia, YIELD AND LEAF NUTRIENT CONCENTRATIONS OF ARABICA COFFEE DURING THE 2ND PRODUCTION CYCLE AFTER ESTABLISHMENT AS INFLUENCED BY NITROGEN RATES AND PLANT-DENSITY, Discovery and innovation, 8(3), 1996, pp. 233-240
Influence of nitrogen application rates; 0, 50, 100, 200 and 400kg N/h
a/year and plant densities, (1332, 2664 and 5330 trees/ha of Arabica c
offee cv. 'SL 283, were investigated at Coffee Research Station, Ruiru
and its sub-station at Koru, Kenya during the second production cycle
after establishment. Leaf nitrogen concentrations increased with incr
easing rates of applied nitrogen, but was not influenced by coffee tre
e densities. Yields of clean coffee increased with the application of
nitrogen, with points of technical and economic inversion being 50kg N
/ha for the three densities at Ruiru; and 100kg N/ha for 1332 and 5330
trees/ha, and 200kg N/ha for 2664 trees/ha at Koru, West of the Rift
Valley. Yields of clean coffee increased with increase of plant densit
y up to 2664 trees/ha and then dropped at 5330 trees/ha. Higher propor
tion of large beans were observed under the highest tree density where
total clean coffee was low.