RESPONSE OF WHEAT (Triticum aestivum L.) VARIETIES TO SOWING METHOD AND FERTILIZER TREATMENTS

ABSTRACT
Field experiments were conducted in 2014/2015 and 2015/2016 dry seasons at the
Research Farm of the Institute for Agricultural Research, Samaru and Kadawa to study
the response wheat varieties to sowing method and fertilizer treatment. The treatments
consisted of three varieties (LACRIWHIT-1, LACRIWHIT-4 and LACRIWHIT-5), two
sowing methods (broadcasting and drilling) and four fertilizer (zero fertilizer control,
NPK at 120 kg N, 60 kg P 2O5 and 60 kg K 2O ha-1, Farmyard Manure at 10 t ha-1 and
combination of NPK (60kg N, 30 kg P 2O 5 and 30 kg K 2O ha-1) and FYM (5 t ha-1)). The
treatments were laid out in a Randomized Complete Block Design and replicated three
times. Growth attributes such as plant height, number of tillers, number of leaves and
crop dry matter varied significantly among the varieties at different sampling periods
and were generally found to be higher in LACRIWHIT-5 than LACRIWHIT-1 and 4.
The variety LACRIWHIT-5 was superior to LACRIWHIT-1 and 4 in most yield
attributes such as number of spike m-2, spike length, weight of grain spike-1, 1000-grain
weight and total biomass at harvest. However, LACRIWHIT-1 and 4 headed, flowered
and matured earlier. LACRIWHIT-1 had higher grain protein (12.28 and 12.59 %) and
gluten content (9.73 and 9.66 %). Growth parameters such as stand count, number of
tillers, number of leaves, leaf area, crop dry matter, CGR, RGR, NAR, days to maturity
and effective tillers were significantly affected by sowing method with drill sowing
giving higher values in most cases than broadcast. Drill sowing also significantly
increased yield components such as number of spike m-2, number of grains per spike,
and grain weight as well as grain yield and grain moisture content. Fertilizer application
significantly increased growth parameters such as plant height, number of tillers,
number of leaves and crop dry matter, crop growth rate and hastened days to 50%
heading, flowering and maturity. High stand count, taller plants and more tillers were
obtained resulting from application of NPK alone or in combination with FYM than
control treatment. Fertilizer application increased tiller production which directly
influence leaf number and LAI of the crop.Days to 50 % heading, flowering and
maturity was relatively earlier in the fertilized plots compared to the unfertilized ones.
Yield components such as spike length, spike m-2, 1000-grain weight, grain per spike
and higher biomass yield of wheat were influenced by fertilizer application. From the
study, highest yield was obtained with the application of NPK alone or in combination
with FYM followed by FYM alone and the least was in the unfertilized control. Positive
and significant correlation was observed between grain yield and most growth and yield
components of wheat. These include plant height, number of tillers m-2, LAI, crop dry
matter, CGR, spike m-2, spike length, spikelets spike-1, number of grains spike-1, weight
of grains spike-1, 1000 grain weight, total biomass and harvest index. Also, LAI
significantly and positively correlated to CGR and RGR. The relationships between
grain yield and days to 50% flowering, heading and maturity was negative. Similarly,
correlation between number of grains spike-1and 1000 grain weight was negative. In the
path coefficient analysis, total biomass production had both the greatest direct effect and
contributed more to grain yield followed by harvest index. The highest positive indirect
contribution was from crop dry matter via weight of grain spike-1as well as number of
tillers m-2via total biomass at Samaru and from weight of grain spike-1via total biomass
at Kadawa. The low residual values obtained in study suggest that the major characters
contributing to the grain yield of wheat were measured. It was realized that only 1.2%,
38.70% and 34.37% at Samaru while at Kadawa 11.54%, 6.0% and 7.35% of the
variability remain unaccounted in 2014/2015, 2015/2016 and their combined mean
respectively. The partial economic analysis revealed that, at both locations application