International Journal of Horticulture 2015, Vol.5, No.1, 1
-
7
1
Research Report Open Access
Effects of Phosphorus and Organic fertilizers on the Yield and Proximate nutrient
composition of lettuce (
Lectuca sativa
) in Southwestern nigeria
K. O. Sanni
1
, B. S. Ewulo
2
1. Department of Crop Production and Horticulture, Lagos State Polytechnic, Ikorodu, Lagos State, Nigeria
2. Department of Crop, Soil and Pest Management, Federal University of Technology, P. M. B. 704, Akure, Ondo State, Nigeria
Corresponding author email
International Journal of Horticulture, 2015, Vol.5, No.1 doi: 10.5376/ijh.2015.05.0001
Received: 10 Dec., 2014
Accepted: 17 Jan., 2015
Published: 10 Feb., 2015
Copyright
© 2014 Sanni and Ewulo, This is an open access article published under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article
:
Sanni and Ewulo, 2014, Effects of Phosphorus and Organic fertilizers on the Yield and Proximate nutrient composition of lettuce (Lectuca sativa) in
Southwestern nigeria, International Journal of Horticulture, 2015, Vol.5, No.1 1-7 (doi
Abstract
A field experiment was conducted to evaluate the effect of different types of organic manure, phosphorus fertilizers and
their combinations on the yield attributes and proximate nutrient composition of lettuce grown in Akure and Ikorodu, Southwestern
Nigeria. The study involved three types of organic manure (poultry, pig and cattle manures) and two types of phosphorus fertilizer
(Ogun Rock Phosphate (RP) and Single Super Phosphate (SSP)) and a control with no fertilizer application resulting in sixteen (16)
treatment combinations. The experimental design was Randomized Complete Block Design (RCBD) with three replicates. Yield was
determined by weighing the fresh harvested lettuce and dry weight at 50 days after transplanting (DAT) and lettuce harvested were
subjected to proximate composition analysis. The result of the study showed that lettuce grown on soil amended with organic manure
combined with SSP and RP at 8t/ha
-1
and 4t/ha
-1
respectively exhibited significant higher yield. It also influenced the proximate
composition positively at harvest compared to control and sole organic manure application. The result obtained clearly indicated that
organic manure combined with phosphorus fertilizers prove to be a sound soil fertility management strategy in the study area. This
should be adopted by would-be farmer of lettuce, as combinations of organic manures increase solubility of phosphorus and improve
lettuce proximate nutrient composition.
Keywords
Organic manure; Phosphorus fertilizers; Proximate composition; Soil fertility management; Treatments’ combinations
Introduction
Continuous crop production in the tropics has
rendered vast area of land unproductive as a result of
physical degradation, loss of soil organic matter and
decreased cation exchange capacity (CEC) and as well
as increased Al and Mn toxicity. As these soils
suffered multi-nutrient deficiencies, application of
organic and inorganic fertilizers has become mandatory
to increase crop growth and yields (Sanni and Adesina,
2012). Crop’s response to fertilizer is a function of the
type of fertilizer applied (Ayodele and Olaniyan,
1982), soil status and the type of preceding crops.
Lettuce (
Lectuca sativa
) is a rapid growing plant that
needs a well-balanced nutritional program in order to
be high yielding and of high quality. Lettuce
marketable and nutritional qualities depend heavily on
the agronomic strategy used. Vast of nitrogen (N)
from fertilizers or a surplus of N can lead to an
increase in nitrate content of plant tissues, synthesis of
N-containing compounds and a decrease in beneficial
phytochemicals (Sorensen et al., 1999). Lettuce
treated with mineral N-fertilizer had higher nitrate
content than the organically fertilized lettuce (Sanchez
et al., 1988). Synthetic fertilizers are believed to
contribute substantially to human, animal food
intoxication and environmental instability/degradation
(Masarirambi et al
.
, 2012). Organic fertilizers can
therefore be used to reduce the amount of toxic
compounds (such as nitrates) produced by
conventional fertilizers in vegetables like lettuce;
hence, improving the quality of leafy vegetables
produced as well as human health. There is increased
demand of organically produced vegetables in view of
its health and nutritional benefits. Since total
eradication of mineral fertilizers is not possible, there
is need to integrate them with organic manures for
sustainable crop production. There is little attention on
the combination of organic and inorganic fertilizer but
the little information on crop’s response to joint
application of chemical and organic manure centered
on the agronomy of production (Adeniyi, 2001;
Akanbi et al., 2010). Therefore the objective of this
study is to assess the effects of different sources and
