8
Applied Sciences & Engineering
www.ijapscengr.com ISSN 2308-5088 [email protected]
RESEARCH ARTICLE
Influence of Complementary Rates of Poultry Manure and Urea Fertilizers on Growth and Yield of Maize (Zea mays L. Walp) in Southeastern Agroecology Zone
Ekesiobi IA1, Ndukwe OO2*, Ezeano CI3, Odukwe RA4 and Nnabuife ELC1
1Department of Forestry and Wildlife Management, Nnamdi Azikiwe University, Awka, Nigeria
2Department of Crop Science and Horticulture, Nnamdi Azikiwe University, Awka, Nigeria
3Department of Agricultural Economics and Extension, Nnamdi Azikiwe University, Awka, Nigeria
4Department of Crop Science and Horticulture, Anambra State Univeristy, Igbariam Campus, Nigeria
A R T I C L E I N F O A B S T R A C T
Received:
Revised:
Accepted:
February 10, 2015 April 23, 2015 May 29, 2015
The complementary effect of organic and inorganic fertilizers on the growth and yield of maize (Zea mays) was studied in the Teaching and Research Farm of Faculty of Agriculture, Anambra State University, Igbariam campus. The treatment comprised of no fertilizer application, 10 t/ha of poultry manure (PM), 5 t/ha of PM combined with 75 kg/ha urea, 10 t/ha of PM combined with 75 kg/ha of urea and sole 150 kg/ha of urea. These were arranged in a randomized complete block design (RCBD) with four replications. Results showed that the combined application of organic and inorganic fertilizers significantly increased the plant height, number of leaves, stem girth, leaf area and leaf area index and number of cobs, ear length, ear diameter, weight of ear, weight of cob, 100 grain weight, grain yield t/ha and above ground weight (yield parameters), particularly 10 t/ha poultry manure combined with 75 kg/ha urea, followed by 10 t/ha poultry manure. The application of 5 t/ha poultry manure combined with 75 kg/ha urea performed better than 150 kg/ha urea as well as the no fertilized plants. The application of organomineral fertilizers, especially 10 t/ha poultry manure combined with 75kg/ha was recommended for enhanced maize production in Igbariam, Anambra State, Nigeria.
Key words:
Complementary rate Growth
Maize
Poultry manure Urea
Yield
*Corresponding Address:
Ndukwe OO
Cite This Article as: Ekesiobi IA, OO Ndukwe, CI Ezeano, RA Odukwe and ELC Nnabuife, 2015. Influence of complementary rates of poultry manure and urea fertilizers on growth and yield of maize (Zea mays L. Walp) in southeastern agroecology zone. Inter J Appl Sci Engr, 3(1): 8-13. www.ijapscengr.com
INTRODUCTION
Maize (Zea mays), which was introduced in Nigeria in the 16th century, is the fourth most consumed cereal during the past two decades, below sorghum, millet and rice (FAOSTAT, 2012). Being among the primary food staples in Nigeria, maize consumption is widespread across the country and among households of different wealth (Cadoni and Angelucci, 2013). It is widely used in the preparation of traditional foods. Main local dishes of maize in Nigeria include akamu, tuwo, gwate, and donkunu, with the cereal cooked, roasted, fried, ground, pounded or crushed form (Abdulrahaman et al., 2006). A steady increase in maize production from 7.4 million metric tons in 2009 to 10.3 million metric tons in 2013 has been reported by Adesina (2014), although most of the production aims at the domestic market, since a negligible part of the production is formally exported (FAOSTAT, 2012). Maize as a major source of carbohydrate is used as food, in livestock diet, in the
textile industry and also in the pharmaceutical industry (Law-Ogbomo and Law-Ogbomo, 2009).
Low soil fertility of tropical soils, particularly low nitrogen, ranks the second most important abiotic constraint to maize production in tropical ecologies (Pingalli, 2001). Intensified land use and the rapid decline in fallow periods, coupled with the extension of agriculture into marginal lands, have contributed to a rapid decline in soil fertility, particularly in sub-Saharan Africa. Nitrogen (N) and phosphorus (P) deficits are a severe and widespread biophysical constraint to smallholder maize productivity, and in turn to the long- term food security of the resource poor in southern and eastern Africa (Sanchez et al., 1997). The means of building up soil organic matter by resource poor farmers in southeastern Nigeria for many decades ago is the practice of bush fallowing. This has been abandoned as a result of limited land area. Most of the soils in Nigeria are strongly weathered and dominated by low-activity clay minerals with low nutrient status (Economic Commission
of Africa, 2001). Therefore, the soils cannot supply the quantities of nutrients required such that the level of crop yield decline rapidly once cropping commences due to the soil degradation and nutrient depletion which have become serious threats to agricultural productivity (Olusegun, 2014).
Recently, farmers are adopting the application of exogenous nutrients in their farms especially in the home gardens. Inorganic fertilizers have relatively been adopted by the resource poor farmers but these fertilizers are relatively scarce and expensive for these farmers aside groundwater pollution. FAO projects that global agricultural production in 2050 will be 60 percent higher than in 2005/07 in order to meet with the projected increase in world population expected to increase by more than two billion people reaching 9.15 billion by 2050 (FAO, 2012). Hence, the global call for Conservation Agriculture which aims at increasing agricultural productivity per unit area allowing farmers to produce more from a smaller area, increase profitability and leave more land under natural vegetation, contributing to environmental sustainability (Marongwe et al., 2010).
Conservation agriculture promotes minimum mechanical soil disturbance, maintenance of soil organic cover, and the use of crop rotations and associations that are suited to local environments. To this end, the utilization of cheaper, most available and accessible fertilizer in crop production will be pertinent. Cow dung, poultry dropping, pig dung and refuse composts are among several organic materials which have been recommended to subsistence farmers in West Africa as soil amendments for increasing crop yield (Olayinka, 1996; Olayinka et al., 1998).
Poultry production business (either for the egg or meat) by peasant farmers is on the increase in Igbariam, Anambra State Nigeria and the environs (Ndukwe et al., 2014). They generate large amount of poultry manure which is abundantly available and relatively cheap. These so called poultry waste are liberally used in home gardens without recommended rates. Complementary combination of organic and inorganic fertilizer could increase the growth and yield of maize. Sustainable soil fertility management in the tropics requires an integrated approach that consists of the efficient use of purchased chemical and organic inputs, crop rotations, and nutrient efficient cultivars (Pingalli, 2001).
The impact of organic manure and mineral fertilizers on soil nutrient differ when they are surface applied or are incorporated into the soil (Steinherd, 2001). The use of inorganic fertilizer however, has not been sustained at farmer’s level in Nigeria and under intensive agriculture due to its scarcity and cost, loss of soil acidity, nutrient imbalance and residual effect (Ayoola, 2006). Inorganic fertilizer have high concentration of nutrients and readily available to crops but its use is hampered by its in accessibility to majority of the farmers due to high cost and infrastructural problems in developing country like Nigeria (Webber et al., 2001). The specific objective of this work was to determine the effect of poultry manure and urea fertilizer and their combination on the growth and yield of maize (Zea mays) in Igbariam, Anambra State Nigeria.
MATERIALS AND METHODS Experimental Site
The experiment was conducted at the Teaching and Research Farm of the Department of Crop Science and Horticulture, Anambra State University, Igbariam Campus, Anambra State of Nigeria in 2014. Igbariam is geographically located within latitude 06° 14’N and longitude 06° 45’E. The rainfall pattern is bimodal between April and October with a mean annual rainfall of 1268.4mm. The dry season falls between November and March. The relative humidity all year round is moderately high with the highest relative humidity of 85% during wet season and 64% during the dry season. The soil is of sandy loam textural class. Prior to the experiment, a composite soil sample of the experimental site as well as the poultry manure were analysed for physicochemical properties. The results are presented in Table 1.
Table 1: Some physicochemical properties of the experimental site and poultry manure utilized
Substrate Soil Characteristics Soil Poultry manure
pH 6.96 -
Sand (%) 67.54 - Silt (%) 23.96 - Clay (%) 8.9 - Textural class Sandy loam - Organic matter (%) 11 58 Nitrogen (%) 0.84 0.95 Phosphorus (mg/kg) 29.236 28.997 Potassium (ppm) 24.883 92.683
Treatment and Experimental Design
The maize variety used was Oba Super 2 which was sourced from Anambra State Agricultural Development Programme (ADP), Anambra, Nigeria. The treatment comprised of sole 10 t/ha poultry manure, 10 t/ha poultry manure + 75 kg/ha urea, 5 t/ha poultry manure + 75 kg/ha urea, sole 150 kg/ha urea and no fertilizer application which served as control. The five treatments were laid out as randomized complete block design with four replicates.
The bed size was 2 m x 2 m (4 m2) with 0.5 m spacing between the bed and 1 m between the replicates. The poultry manure was incorporated in the plots that were sampled to receive poultry manure and was left for a week before planting the maize seed. The urea fertilizer was applied two weeks after planting using ring method of application.
Cultural Practices
The experimental site was cleared of the existing vegetation. The soil was ploughed and harrowed. Beds of 2 m x 2 m (4 m2) dimension were manually constructed with hoe and spade. Spacing between beds within a replicate was 0.5 m spacing while 1 m separated the replicates. The poultry manure was incorporated in the beds that were sampled to receive poultry manure and was left for a week before planting the maize seed. However, the urea fertilizer was applied two weeks after planting using ring method of application.
Three maize seeds were planted per hole and this was later thinned down to one seedling per hole. The plant spacing was 70 cm x 50 cm, between and within rows,
respectively. Weeding was manually done, starting from two weeks after planting and was repeatedly done as the need arose to reduce the competition between the crop and weeds for space, water, light and nutrients. Field sanitation was maintained including the field borders which were kept clean to minimize encroachment by insects and rodents.
Data Collection
Data were collected from six plants at the middle of each plot which were randomly selected and tagged.
Observations for growth parameters commenced from 4 weeks after planting (WAP) and were collected at two weeks interval (that is, 4, 6, 8, 10 and 12 WAP). The growth parameters included plant height (cm) measured from the base of the plant to the tip of the plant with a measuring meter tape, number of leaves collected by counting, stem diameter (cm) measured by using a measuring meter tape to determine the circumference of the maize plant at 2 cm above the ground, leaf area (cm) obtained by measuring the longest and broadest leaf with a measuring tape. The leaf length was measured from the point of attachment of the leaf to the tip of the leaf while the leaf width was measured across the widest portion of the surface of the leaves.
The yield parameters were number of cobs obtained by counting the number of cobs per plant, ear length (cm), that is, harvested cob together with the husk, measured with measuring meter tape, ear diameter (cm) obtained by measuring the widest part of the cob with meter tape, cob (without the husk) length and diameter, weight of ear and cob obtained by weighing the cob with and without the husk, respectively with the use of a sensitive weighing scale, 100-grain weight obtained by weighing hundred seeds per cob after drying to 14% moisture content. The above ground weights of plants were cut from the base when they were dry and their weights were obtained with a sensitive weighing scale.
Data analysis
All the data collected were subjected to statistical analysis following the procedure for randomized complete block design (RCBD) using GENSTAT Edition 3 Release 7.2 DE (GENSTAT, 2007). Treatment means were
separated using least significant difference (LSD) at 5%
level of significance.
RESULTS
Plant height and stem girth
Maize plant height at 4, 6, 8, 10 and 12 WAP generally increased with fertilization (Table 2). At 4 WAP, the complementary rate of 10 t/ha poultry manure and 75 kg/ha urea produced tallest plants in the periods examined. However, this plant height (47.73 cm) observed with this complementary dose was statistically at par with the value (46.62 cm) obtained when only 10 t/ha poultry manure was applied. On the other hand, at 6, 8, 10 and 12 WAP, the incorporation of only 10 t/ha poultry manure enhanced the production of tallest plants. The plant height obtained as a result of 10 t/ha poultry manure soil amendment was statistically similar to those plant heights obtained when either 10 t/ha poultry manure and 75 kg/ha urea or 5 t/ha poultry manure and 75 kg/ha urea was used to amend the soil. Shortest plants were significantly (P<0.05) associated to plants that received no soil amendment.
Fertilizer application significantly influenced the maize stem girth only at 4 WAP (Table 3). Widest stems were obtained from plants that received complementary application of 10 t/ha poultry manure + 75 kg/ha urea and sole application of 10 t/ha poultry manure.
Number of leaves and leaf area index
The number of leaves a 4, 6, 8, 10 and 12 WAP were significantly (P<0.05) influenced by fertilizer application (Table 4). Joint application of 10 t/ha poultry manure and 75 kg/ha urea produced highest number of leaves at 4, 6, 8, 10 and 12 WAP. The number of leaves, however, produced by this joint application in the assayed weeks were not significantly (P>0.05) different from the values obtained from plots fertilized with either sole 10 t/ha poultry manure or joint application of 5 t/ha poultry manure and 75 kg/ha urea. Of course, the least number of leaves at 4, 6, 8, 10 and 12 WAP were produced by plants that were not fertilized.
The influence of fertilizer application on leaf area index was only observed at 4 and 12 WAP (Table 5). At 4
Table 2: Effect of comparative rates of poultry manure and NPK 15:15:15 on maize plant height at 4, 6, 8, 10 and 12 WAP Weeks after planting (WAP)
Fertilizer 4 6 8 10 12
No application 32.06 49.30 61.50 75.30 87.60 10 t/ha poultry manure 46.62 75.30 87.70 100.00 109.30 10 t/ha poultry manure + 75 kg/ha urea 47.73 70.70 80.30 99.00 105.50 5 t/ha poultry manure + 75 kg/ha urea 39.94 69.40 81.80 94.70 105.40 150 kg/ha urea 30.44 51.50 62.60 76.20 85.60
LSD0.05 3.61 10.79 10.14 7.95 8.99
Table 3: Effect of comparative rates of poultry manure and NPK 15:15:15 on maize stem girth of maize at 4, 6, 8, 10 and 12 WAP Weeks after planting (WAP)
Fertilizer 4 6 8 10 12
No application 2.342 3.82 3.780 4.862 5.425 10 t/ha poultry manure 3.533 3.996 4.250 5.129 5.738 10 t/ha poultry manure + 75 kg/ha urea 3.717 4.238 4.330 5.283 5.896
5 t/ha poultry manure + 75 kg/ha urea 3.033 4.225 4.280 5.029 5.867 150 kg/ha urea 2.395 3.850 4.180 5.054 5.779
LSD0.05 0.395 ns ns ns ns
Table 4: Effect of comparative rates of poultry manure and NPK 15:15:15 on number of leaves of maize at 4, 6, 8, 10 and 12 WAP Weeks after planting (WAP)
Fertilizer 4 6 8 10 12
No application 9.21 10.58 13.13 14.46 14.42 10 t/ha poultry manure 12.42 13.37 15.33 16.42 16.54 10 t/ha poultry manure + 75 kg/ha urea 12.54 13.46 15.37 16.83 16.88
5 t/ha poultry manure + 75 kg/ha urea 12.21 13.25 15.25 16.54 16.67 150 kg/ha urea 9.83 10.96 13.79 16.21 16.21
LSD0.05 0.850 0.725 1.033 0.707 0.644
Table 5: Effect of comparative rates of poultry manure and NPK 15:15:15 on leaf area index of maize at 4, 6, 8, 10 and 12 WAP Weeks after planting (WAP)
Fertilizer 4 6 8 10 12
No application 0.019 0.039 0.050 0.074 0.102 10 t/ha poultry manure 0.034 0.040 0.052 0.076 0.113 10 t/ha poultry manure + 75 kg/ha urea 0.032 0.041 0.051 0.077 0.120
5 t/ha poultry manure + 75 kg/ha urea 0.027 0.042 0.052 0.075 0.111
150 kg/ha urea 0.018 0.036 0.050 0.073 0.110
LSD0.05 0.004 ns ns ns 0.011
Table 6: Effect of comparative rates of poultry manure and NPK 15:15:15 on yield and yield components of maize Fertilizer Number
of cobs Cob weight
(g)
Ear weight
(g)
Cob length
(cm)
Cob diameter
(cm)
100-grain weight (g)
Grain yield (t/ha)
Above ground biomass (g) No application 1.33 118.20 195.70 37.70 14.71 18.96 1.69 137.70 10 t/ha poultry manure 1.63 172.30 309.80 35.60 17.74 24.55 2.10 226.70 10 t/ha poultry manure + 75 kg/ha urea 1.96 179.00 319.50 31.00 18.96 23.52 2.02 279.30 5 t/ha poultry manure + 75 kg/ha urea 1.75 165.50 294.70 33.50 17.66 23.55 2.02 268.20 150 kg/ha urea 1.67 142.60 214.80 31.30 16.87 20.09 1.72 187.30 LSD0.05 0.27 29.27 46.02 ns 2.24 2.67 0.23 21.52
WAP, the leaf area index was highest in plants that received either sole 10 t/ha poultry manure or combined application of 10 t/ha poultry manure and 75 kg/ha urea.
Whereas at 12 WAP, the application of fertilizer generally produced higher leaf area index than the control (no fertilized) plants. Plants that received no fertilizer produced least leaf area index at the 4 and 12 WAP.
Yield and yield components of maize
The application of either 10 t/ha poultry manure + 75 kg/ha urea or 5 t/ha poultry manure + 75 kg/ha urea enhanced the production of highest number of cobs (Table 6). The ear diameter, ear and cob fresh weight were highest in plants fertilized with the combination 10 t/ha poultry manure and 75 kg/ha urea, although the values obtained for these yield parameters were statistically similar with those obtained from plants fertilized with either sole application of 10 t/ha poultry manure or joint application of 5 t/ha poultry manure and 75 kg/ha urea.
On the other hand, highest 100-grain weight and grain yield per hectare were significantly produced by the sole application of 10 t/ha poultry manure which were significantly (P>0.05) at par with joint application of either 10 or 5 t/ha poultry manure and 75 kg/ha urea. The aboveground biomass at dry basis was highest in plots fertilized with combined application of 10 t/ha poultry manure and 75 kg/ha urea. Expectedly, the no fertilized plots consistently produced plants with least values for all the yield and yield components of maize.
The ranking of the growth and yield performances of maize with respect to the fertilizer applications in a descending order was 10 t/ha poultry manure + 75 kg/ha urea
> 10 t/ha poultry manure > 5 t/ha poultry manure + 75 kg/ha urea > 150 kg/ha urea > control (no fertilizer application).
DISCUSSION
Among the five fertilizer treatments studied, the non- fertilized plants were shortest, had narrowest stems, least number of leaves and lowest leaf area index. This could be due to deficiency of soil nutrients as revealed by the soil physicochemical properties of the soil experimental site. Plants that received fertilizer generally had greater growth performance with respect to the plant height, stem girth, number of leaves and leaf area index relative to the non-fertilized plants. This also buttressed the fact that the experimental site was deficient in nutrients and required soil amendment for better performance of crops.
The significant increase in plant height, stem girth, number of leaves and leaf area index in the observed week intervals with the application of either the 10 t/ha poultry manure + 75 kg/ha urea or sole 10 t/ha poultry manure or 5 t/ha poultry manure generally revealed the beneficial effect of fertilizers in maize production. The joint application of 10 t/ha poultry manure and 75 kg/ha urea had higher values for these growth parameters reflecting that this soil amendment might have supplied the adequate nutrients needed (particularly nitrogen which enhances vegetative growth of plants) at this growth stage. In addition, the combination of poultry manure might have assisted in improving the soil biophysical condition for better ramification, nutrient absorption and uptake by the maize roots. This corroborates with the report of Owolabi et al. (2013) that the combination of organic and inorganic fertilizers (poultry manure and NPK 15-15-15) had significant effect (P<0.05) on number of leaves, number of fruits and weight of fruits and fruit yield of Solanum gilo. The report of Okokoh and Bisong (2011) also underscored the nutrient efficiency of combining organic
and inorganic nutrient sources in crop production.
Similarly, Satyanarayana et al. (2002) strongly advocated for supplementary use of inorganic fertilizer along with organic manure in order to promote the decomposition of the latter. He also realized that using organic manure with inorganic fertilizer raises the yield of rice by about 25%
over and above that obtained using inorganic fertilizers alone.
There must have been a rapid and adequate release of nitrogen content in the 75 kg/ha urea fertilizer during the vegetative stage as well as the while the enhancement of the biophysical characteristics of the soil by the poultry manure due to the integration of 10 t/ha poultry manure and 75 kg/ha urea. Poultry manure has been reported to contain about 16 kg nitrogen, 20 kg phosphorus (P2O5) and 12 kg potassium (K2O) per hectare including micronutrients (Cooperband, 2002). It promotes soil structure, soil tilts, cation exchange capacity, water holding capacity and crumb formation. It also promotes infiltration, protects against erosion and facilitates the spread and penetration of plant roots. In addition, the slow release nature of organic fertilizer prevents loss of nutrients through leaching and enhances synchronization of nutrient release with uptake by the crop (Adeoye et al., 2008).
The application of poultry manure either as sole (10 t/ha) or in combination with urea (that is, 5 or 10 t/ha poultry manure and 75 kg/ha urea) generally increased the yield and yield components of maize. This emphasizes the slow release nature of poultry manure as this fertilizer sustained the growth and development of maize. Highest values for all the yield parameters attributed to the joint application of 10 t/ha poultry manure and 75 kg/ha urea showed that this soil amendment provided adequate nutrients for the optimum growth and consequent yield increase of maize. Law-Ogbomo and Law-Ogbomo (2009) opined that the height of plant is an important growth character which is directly linked with the productive potential of plants in terms of grains. In addition, Saeed et al. (2001) asserted that the optimum plant height is claimed to be positively correlated with productivity of plant. Similarly, increase in stem girth is a reflection of retention of appreciable amount of assimi- lates in the stem for leaf production (Law-Ogbomo and Law-Ogbomo, 2009).
The increase in maize yield and yield attributes with the application of either sole 10 t/ha poultry manure or 10 t/ha poultry manure + 75 kg/ha urea or 5 t/ha poultry manure + 75 kg/ha urea could be mainly due to better nutrient use efficiency and better grain development.
There must have been adequate mineralization of nutrients and proper mobilization of the essential nutrient elements like nitrogen, phosphorus and potassium by the organomineral fertilizers as well as enhancement of soil biophysical properties which brought about better crop performance. This finding is in line with the view of Ndukwe et al. (2014) that the integration of organic and inorganic fertilizers in maize production is beneficial and sustainable as the application of 5 or 10 t/ha poultry manure and 150 kg/ha NPK 15:15:15 produced greater yield and yield components of maize. Similarly, Adeniyan and Ojeniyi (2005) found that integrated application of poultry manure and NPK fertilizer increased maize yield
compared with poultry manure or inorganic fertilizer applications alone.
Grain yield of a crop had been noted to be the end result of many complex morphological and physiological processes occurring during growth and development of crop (Khan et al., 2008a). Plants treated with 150 kg urea significantly increased maize grain yield over the non- fertilized plots (control plants) but had similar effect with plants that were amended with poultry manure. This emphasized the necessity of applying fertilizer in an impoverished soil towards greater crop yield. The greater grain yield due to the application of poultry manure than urea also accentuated the efficacy of poultry manure over urea with respect to sustaining growth and development of crops. Poultry manure poses high organic matter than urea (which contains only an element, nitrogen) hence, will have the ability to improve the soil physical, chemical and biological properties, most importantly increasing the organic matter content of the soil thereby providing more sites for cation exchange. Furthermore, these nutrients in poultry manure are released gradually (Adeoye et al., 2011; Ogunlade et al., 2011) unlike inorganic fertilizers that release its nutrients rapidly.
Conclusion
This study showed that the growth and yield performance of maize was better influenced by the application of complementary dose of 10 t/ha poultry manure and 75 kg/ha urea thus revealing the superiority effect of integrated nutrient supply over sole use of either inorganic or organic source with respect to balanced nutrient supply (Khan et al., 2008b), control of soil acidity, extended residual effect (Adeoye et al., 2011) improvement on soil physical and chemical properties than can be derived from the use of either inorganic or organic manure and crop yield (Ayeni et al., 2009; Ewulo et al., 2009). Hence, the integration of 10 t/ha poultry manure and 75 kg/ha urea could be utilized for increased maize production in Igbariam Anambra State, Nigeria and any other similar agroecological area.
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