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International Journal of Horticulture 2014, Vol.4, No.14, 1
-
10
http://ijh.biopublisher.ca
1
Research Report Open Access
Drip irrigation scheduling for optimizing productivity of water use and yield of
dry season pepper (
Capsicum annuum
L) in an inland valley swamp in a humid
zone of Nigeria
Agele S.O.
1
, Agbona I.A.
1
, Ewulo B.S.
1
, Anifowose A. Y.
2
1. Department of Crop, Soil & Pest Management, Federal University of Technology, PMB 704, Akure, Nigeria
2. Department of Remote Sensing and Geoinformatics (RSG), Federal University of Technology, PMB 704, Akure, Nigeria
Corresponding author email
International Journal of Horticulture, 2014, Vol.4, No.14 doi: 10.5376/ijh.2014.04.0014
Received: 18 May., 2014
Accepted: 12 Sep, 2014
Published: 13 Oct., 2014
Copyright
© 2014 Agele et al., 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
:
Agele et al., 2014, Drip irrigation scheduling for optimizing productivity of water use and yield of dry season pepper (
Capsicum annuum
L) in an inland valley
swamp in a humid zone of Nigeria, International Journal of Horticulture, 2014, Vol.4, No.14 1-10 (doi: 10.5376/ijh.2014.04.0014)
Abstract
The effects of drip irrigation schedules (weekly and fortnight intervals) on water use, yield and water productivity of dry
season pepper grown in inland valley swamp was investigated between December 2009 and May, 2010. The first planting (December,
2009) adequacy of soil moisture from planting to date of first flowering was assumed, thereafter irrigation was imposed during
reproductive growth. In the second sowing (Janaury, 2010), pepper seedlings were drip-irrigated weekly and fortnightly from
transplanting to fruit harvest. In both experiments, irrigation was imposed using low-head (gravity) drip system weekly and
fortnightly and 1.38 litres of water per plant at each irrigation while soil moisture storage ranged from 100 to 50 % of plant available
water. Higher root biomass and densities at soil depths were obtained for fortnight irrigation over weekly. Within the crop root zone,
and across irrigations, soil moisture contents ranged between 14.7 and 11.8% for the respective surface (0 – 20cm) and lower (30-45
and 45-60 cm) soil depths. Soil moisture tension were - 7 to -10 bar and -10 to -14 bar for the respective seedling establishment and
reproductive growth phases. Total fruit yield and water productivity were higher (8.8 and 1.85 kg/ha/mm) in December over January
(8.5 t ha
-1
and 1.25 kg/ha/mm) sowing. In addition, over weekly (9 t ha
-1
) irrigation, fruit yield obtained (8.1 t ha
-1
) under fortnight
irrigation translated to 24 % water savings.
Keywords
Inland floodplain; Root; Crop water stress index; Moisture depletion
Introduction
In sub-Saharan Africa, inland wetlands constitutes
about 135million ha of land (IWMI, 2002), However,
the soil, agriculture and water resources potentials of
inland valley swamps had not been fully utilized. The
underutilization may be due to inadequacy of
technical know-how (technological packages) and
strategies for efficient management of water for
irrigation (IWMI, 2002; National Fadama Development
Project, 2000). Dry season crop production (mostly
vegetables) in inland valley swamps (F
adama
schemes) characterized by shallow water tables, is a
common feature of the farming system of the tropics
(National Fadama Development Project, 2000).
Variable water table depths (0.3, 0.5, 0.8, 1.0 and
1.5m) are characteristics of inland valley swamps
(fadama ecosystems) of the humid tropics (Ogwu and
Babalola, 2002, IWMI, 2002). The variable water
table depths would imply differences in the
contributions of water tables via capillary rise (upflows)
to crop water requirements (evapotranspiration) at
different growth stages of the crops. In general, crops
grown in the dry season in the humid tropics
encounter variable depths of water table. In
circumstances of declining water table depths, these
crops will encounter increasing intensities of soil
moisture deficit in situations where the upper half of
the soil is dry and soil water in the lower horizons
becomes unavailable to crops. The crops are therefore
exposed to temperatures and soil and air moisture
deficit stress at different phenological growth stages.
Capillary rise (upflows) can constitute significant
component in the root zone water balance of crops
grown in inland valley swamps especially those
characterized by shallow water table depths (Benz.,
1984, IWMI, 2002). Despite the realization that fresh
shallow water tables can help to meet crop water
requirement, knowledge on how best to incorporate
upflow from shallow water tables in irrigation
scheduling is limited (Hurst., 2004; Ayars., 2006).
Reduced irrigation above water tables does not only
results in more efficient use of water resources, it also