|Home Instructors Journals ContactUs|
THE RESPONSE OF CORRIDOR-GROWN AMARANTHUS CRUENTUS L. TO LIQUID ORGANIC FERTILISER
I. M. Ojeifo, G.U. Nnaji, and S. C. Nnoka
Department of Agronomy, Delta State University, Asaba Campus
Home vegetable production is more likely to provide the needed nutrients for families than the existing market system because of its freshness. To improve vegetable crop production, a study was conducted to assess the response of Amaranthus. cruentus L. to liquid organic fertilizer in a pot experiment. The results obtained showed that the growth and yields of A. cruentus increased with increase in the rate of liquid organic fertilizer applied and the highest rate of 48l/ha-1, was superior to other rates of application in plant height, plant girth, number of leaves, leaf area and fresh mass values. Marketable yield and total dry matter increased linearly with application rate up to the highest N application rate (48l/ha-1). Proximate analysis of A. cruentus showed that plants, which received the fertilizer at the rates of 48l/ha-1 and 24l/ha-1, contained higher percentages of crude protein, crude fibre and ether extract than lower rates of fertilizer application. The marketable yield of A. cruentus grown at the rate of 24l/ha-1 produced the best marginal return on profit of US$392.8/ha-1. This rate of the fertilizer application is the same recommended by the manufacturer for the production of tomatoes.
Key words: A. cruentus, liquid organic fertilizer, powerplant, urban agriculture
Rapid urbanization in developing countries presents an enormous challenge to decision-makers and other stakeholders with meeting the basic needs of the urban population (Wade, 1986). Growing vegetables in urban gardens provides better production control and produce quality, while via the use of supplementary irrigation gives year round supply of fresh vegetables rather than relying on imported produce from rural areas which rarely reach the urban market in fresh state (Noordhuis, 1995). The largest growing areas for community-based production of vegetables are closest to homes. Production sites may include parks, court yards, roof tops, balconies, alley ways and containers of all sorts between buildings (Boland, 2002). This type of urban gardening is referred as “corridor” production. The most widely grown vegetable crop in the humid tropics is perhaps Amaranthus spp, which are high in nutritional value (Norman, 1990; Baile, 1997; Shippers, 2001). Corridor vegetable production stems from the fact that people living in many cities, especially, the poor have limited access to production resources. The soil may be compacted from previous construction activities and may lack adequate drainage (Wade, 1986).
which organic wastes from food, manufacturing and sewage are recycled instead of festering in dumps and polluted waterways. Organic wastes are converted to compost while domestic waste water can be used for irrigating vegetables (Smit, 2002). In a study, Guo (2000) reported that liquid organic fertilizer increased the organic matter content of soil and increase disease resistance and drought tolerance of A. cruentus. Ismail and Hasabo (2002) asserted that liquid organic fertilizer can be beneficial to crop since it is supplying nutrients to plant grown in cold soils, and soils generally low in fertility or to plants in pots. According to Bockman, et al. (1990), organic fertilizers are used, not for the direct benefit of the plants, but to intensify the life process in the soil. They also asserted that mineral fertilizers are becoming less popular because they are thought to reduce interactions between soil and plant. Continuous cropping with excessive application of mineral fertilizer as NPK alone can increase soil acidity and physical degradation, while aggravating nutrient inbalance resulting in declining crop yields (Ojeniyi, 2000a; 2000b). Ano and Asumugha (2000) reported lower cost benefit ratios for inorganic fertilizer-based systems featuring integrated use of both mineral and organic fertilizer or dependent on organic nutrient sources. Agbede and Kalu (1995) reported that fertilizers were excessively expensive while farmers also, did not have excess to either fertilizer or funds to buy it during the growing season.
Many urban gardening projects have failed because the gardeners do not understand the need for fertilizing soils in urban conditions and how to effectively address specific soil management and environmental constraints. In fact, studies have shown that the incidence of malnutrition is often greater in cities than in rural areas (Wade, 1986). Today, due to urban expansion, local vegetable production near most cities has been sharply reduced and therefore need to be complemented. Manga et al. (2004) reported a dearth of information on the response of Amaranthus growth and yield to fertilization in Nigeria. The production of A. cruentus in corridor production systems will not only improve the nutritional status of the urban residents, but would also generate income, thus improving the quality of life of millions of urban residents (Wade, 1986). The objective of this study is therefore to assess the response of corridor-grown A. cruentus L. to liquid organic fertilizer.
Materials and Methods
The experiment was conducted at the Delta State University, Asaba Campus, Asaba (060 14``N and 060 49`` E). Asaba is in the Southern Nigeria, West Africa. The town lies within the tropical rainforest zone and it is characterized by rainfall periods of between April and October, with an annual rainfall ranging from 1,500 mm to 1,850 mm. The maximum ambient temperature of the area is 28°° C and minimum temperature is 24.4°° C. The mean monthly soil temperature at 100cm depth is 28.30 C (Asaba Meteorological Station, Delta State).
The trademark of liquid organic fertilizer used in this study is Powerplant, which is a specially formulated natural liquid organic fertilizer that has developed over many years through extensive research and development. Powerplant contains N(18%), P (8%), K (4.5%) Mg (0.56%), Mo (0.002%), S (1.8%), Fe (0.10%), Mn (0.10%), Cu (0.03%), Bo(0.03%) and Cobalt (0.002%). Seeds of A. cruentus (cultivar-NHAC3) obtained from National Horticultural Research Institute (NIHORT) in Ibadan, Nigeria, West Africa, were mixed with sand at the rate of 10 g seed/kg of dry sand to ensure even distribution and sown directly in the pots at a spacing of 10 cm x 10 cm, giving a total of seven plant stands per pot. The seedlings were thinned to two plants per stand, one week after seedling emergence. Pots were watered twice weekly at the rates of 3 l/pot-1 and pots were weeded regularly. The fertilizer was applied via foliar application following the manufacturers recommended ratio of 1:200 liquid organic fertilizers to water (GPI, 2002). Liquid fertilizer application rate was applied into two doses at 3 and 4 weeks after sowing (WAS). The application rates were based on recommended rate on a per hectare basis, which were then converted to a container basis assuming one hectare contains 2 x 106 kg soil (Sanchez and Logan, 1992).
Non-destructive measurements started two weeks after sowing and were taken at weekly intervals by measuring nine plants per pot. Germination and number of leaves were measured by direct counting. Plant height, were measured using a ruler. Plant girth was measured using veneer callipers.
Plants were harvested at 6 WAS, by cutting plants back to 20 cm from the base. Data collected on harvest yield were leaf area using graph method, fresh and dry weights of leafs and stems along with total marketable yield and total dry matter production. Drying of the samples was done according to IITA (1979) recommendation. Crude protein, crude fibre and ether were determined using the procedure outlined by IITA (1979). The plants were allowed to regenerate after the first harvest and growth data were collected on the ratoons from two weeks after harvesting (WAH). The measurements taken were number of branches, number of leaves and the length of branches.
However, the yield data for the second rations could not be taken because rodents interfered with the treatments before the yield data could be taken.
Data collected from this study were analyzed using a one-way analysis of variance (ANOVA) and the means obtained were separated using Duncan’s New Multiple Range Test (DNMRT). Economic analysis of the marketable yield was carried out using the relationship between marginal costs and marginal revenue to determine the level of fertilizer input as a recommendation domain.
The result of the soil analysis before sowing showed that the soil used for this experiment was sandy loam and this soil is suitable for A. cruentus production. The soil was acidic, low in plant nutrients, organic matter content and cation exchange capacity (Table 1). Because of the low fertility status of the soil. A. cruentus was expected to show a clear response to LOF application.
The seeds of A. cruentus used for the experiment were very viable. Seedling emergence occurred two weeks after sowing with 98 percent seedling emergence. Significant differences (P<0.05) were observed in plant height from 4-6 WAS. Plants that received 48l/ha-1 – 24l/ha-1 had similar plants height but were significantly taller than plants receiving the lower LOF application rates (Table 2). Plant girths increased linearly with higher rates of LOF. Plants that received 48l/ha had the highest girth development while those that did not receive fertilizer had the least girth (Table 2). The number of leaves increased with time for the various application rates of LOF and the 48 l/ha-1 treatments out yielded all the other treatments (Table 2). Leaf area at 6 WAS increased with organic liquid fertilizer rates and was highest for the 48 l/ha-1 treatment (Figure 1).
Yield and ratoon growth
Proximate composition of A. cruentus
The result of tissue analysis showed that A. cruentus, which received 48 l/ha of LOF, contained higher proportion of stem crude protein and leaf crude fibre, while 24 l/ha contained higher percentage of leaf crude protein and stem crude fibre. Plants that received either 24 or 48 l/ha-1 had similar leaf and stem ether extract values, which in turn were higher than those 0, 6 and 12 l/ha (Table 5)
Economic analysis of marketable yield of A. cruentus
The marginal returns increased with increase in the rate of LOF application and peaked at 24 l/ha with a marginal return of US$ 397.8 (N55,500.00) per hectare. Thereafter the marginal return declined with increased rate of LOF application (Table 6)
The increase in vegetative growth and development of A. cruentus with high application rates of LOF was probably related to its high N content. Abidin and Yasdar (1986) reported that nitrogen enhanced above-ground vegetative growth of A. cruentus. The plant growth and yield response obtained in this study compared favourably with those of other workers (Oluyolaji, 1989; Olufolaji and Tayo, 1989; Ado, 1995). The result obtained in this study is also in agreement with earlier work done by Danbaba (2003) who reported that high rates of LOF increased the growth and development of sweet potato. In that study, plants, which received LOF at the rates of 24 and 12 l/ha-1, gave superior vegetative growth and development compared to lower rates of LOF. Increased plant height, number of leaves, leaf area and plant girth at higher LOF rates is indicative that powerplant LOF enhances overall plant growth of A. cruentus. This product contains nitrogen and micronutrients in adequate amounts for increased vegetative growth of the crop. Microsoft Corporation (2003) reported that LOF is especially effective for giving fast growing plants such as Amaranthus spp. an extra boost during growing season. Use of foliar spray are, therefore, helpful in overcoming deficiencies in nutrient availability under low fertility.
The corresponding increase in crude protein, crude fibre and ether extract with high rates of LOF application to A. cruentus is noteworthy. Moreover, based on the apparent linear increase in the yield of A. cruentus with increasing levels of LOF as was seen in Table 3, one could argue that yields may continue to increase greater than 48 l/ha-1 however, based on the results of the cost benefit analysis, application rates above 24 l/ha-1 may not be cost effective. This is also, the rate recommended by the manufacturers for tomato production (GPI, 2002). At this rate of LOF application, marketable yield (77.6 t/ha) almost doubled the values obtained by earlier workers (Ayodele and Oluyolaji, 1992; Omolayo, 2003). The superior yields obtained here may be attributed to more efficient utilization of foliar applied nutrients, effective plant protection and weed control protocols. Preliminary research results using the LOF show that its use does not result in build-up of residuals and increased vegetable yield (GPI, 2002). The overall result is consistent with the work of Ipinmoroti et al. (2003) on the use of locally blended organic fertilizer on A. cruentus. They reported that organic fertilizers were observed to enhance the growth and yield of A. cruentus.
This study showed that LOF applied up to the rate of 48 l/ha improved the yield of A. cruentus. However, application rate of 24l/ha gave the highest marginal revenue of yield. Based on this positive growth and yield response of corridor grown Amaranthus to powerplant liquid organic fertilizer application, the use of the product may afford urban dwellers with a suitable nutrient source for improving the production of vegetables in their homes, thereby providing them with year round fresh vegetables.
Abidin, Z. and Yasdar, H. (1986). Effects of nitrogen fertilization on nutrient content of four amaranth varieties. Amaranth Newsletter. December, 1986. pp 1-3
Ado, M. (1995). Effect of Nitrogen and Phosphorus on the Growth and Yield of Vegetable Amaranth (A. cruentus) B. Tech. Agric.Project. Abubakar Tafawa Balewa University, Bauchi. P 20.
Ayodele, O. J. and Olufolaji, A. O. (1992). Evaluation of Height and Frequency of Cutting for optimum Production of Amaranthus and Celosia. Proc. 5th Ann. Conf. Hort. Soc. Zaria, Nigeria.
Bailey, J. M. (1997). Pacific foods: The leaves we eat. SPC Handbook N0 31 South Pacific Commission, New Caledonia.
Bockman, O. C., Kaarstand, O., Lie, O. H. and Richards, I. (1990). Agriculture and Fertilizers. Agricultural Group, Norsk Hydro a. s. Oslo, Norway.
Boland, J. (2002). Urban agriculture: Growing vegetables in cities. Agrodok Series, No 24. Agromisa Foundation, Wageningen, The Netherlands.
Danbaba, A. K. (2003). Evaluation of Powerplant TM Liquid Organic Fertilizer for potato production in Plateau State. Nigeria (Paper submitted to Greenplanet Int., Jos, Nigeria). National Root Crops Research Institute, Vom, Nigeria.
G. P. I. (2002). Green Plant International Gazette 1:1-24.
Guo, T .J. (2000). The availability of G-typed biofertilizer (GBF) and its impact upon ecosystem, plant growth and nutrient status. Research Proceedings in Plant Production and Nutrition. 99:419-427
Ipinmorotti, R. R.., Adeoye, G. O., and Daniel, M. A. (2003). The comparison of locally blended organic fertilizer on Amaranthus cruentus L. production at Ibadan, South Western Nigeria. Proceedings of the 21at Ann. Conf. Hort. Soc. Nig. Lagos, Nigeria, Pp 58-61.
Ismail, A. E. and Hasabo, S. A. (2002). Evaluation of some new Egyptian biofertilizers. Plant nutrients and a biocide against Meloidogne incorgnita root knot nematode infecting sunflower. Pakistan Journal of Nematodes. 18: 39-49.
Manga, A. A., Oseni, T. O., and Auwalu, B. M. (2004). Analysis of growth and yield of grain amaranth (Amaranthus cruentus) as affected by nitrogen and phosphorus application. Proc. of the 22nd Ann. Conf. of the Hort. Soc. of Nig., Lagos, Nigeria. Pp 85-90.
Microsoft Cooperation. (2003). Organic farming. Encarta Encyclopaedia 99: 1-4
Noordhuis, K. T. (1995). The complete book of gardening. Michael Friedman Pub. Group Inc., China. pp 29-165.
Norman, J. C. (1990). Advances in tropical leafy crops in Ghana. World Crops 24: 217-219.
Olufolaji, A. O. (1989). Response of four Amaranthus cultivars to nitrogen level and harvesting methods. Test of agrochemical and cultivars. Annals of Applied Biology. 10: 166-67.
Olufolaji, A. O. and Tayo, T. O. (1989). Performance of several morphotypes of Amaranthus cruentus L. under two harvesting methods. Tropical Agriculture (Trinidad). 66: 273-276.
Ojeniyi, S. O. (2000a). Effect of goat manure on soil nutrient contents on okra yield in a rainforest area of Nigeria. Applied Tropical Agriculture 5:2-23.
Ojeniyi, S. O. (2000b). Soil Fertility Management and plant Nutrient Sources in Nigeria. Paper presented at 30th Annual Conference of Agric. Soc. of Nigeria., Bauchi. Abstracts P35.
Omolayo, F. O. (2003). Response of Amaranthus hybridus to different levels of Nitrogen Fertilizer. Proceedings of the 21st Annual Conference Horticultural Society of Nigeria. 2:95-101.
Sanchez, P. A., Logan, T. J. (1992). Myths and Science about the Chemistry and Fertility of Soils in the Tropics. America Soil Science Society. Pp 9-13.
Schippers, R. R. (2000). African indigenous vegetables:.An overview of the cultivated species. Natural Resources Institute, Chatham, UK.
Smit, J. (2002). Gardening for the future of the earth. Seeds of change. Urban Agricultural Research Network, Latin America.
Wade, I. (1986). City Food. Crop selection in the third world cities. Urban Resources System Inc. San Francisco, U. S. A..
Table 1: Physical and chemical properties of soil used for growing Amaranthus
Table 2: Effect of liquid organic fertilizer (Powerplant) on plant height, girth and number of leaves of A. cruentus.
Number of leaves
Values within the same column followed by the same letters for each set of variable on the
same columnare not significantly different at P 0.05. Mean separation by DNMRT.
Table 3: Effects of liquid organic fertilizer on yield and yield (g/plot) component of Amaranthus
*Values within the same column followed by the same letters are not significantly different at
P 0.05, Mean separation by DNMRT
Table 4: Effect of liquid organic fertilizer on vegetative growth of A. cruentus
*Values within the same column followed by the same letters are not significantly different
Table 5: Proximate analysis of A. cruentus grown with liquid organic fertilizer
Table 6: Economic analysis of A. cruentus produced from different application rates of
liquid organic fertilizer.
*Cost of LOF (Power plant) = N1, 000 per litre
US $1 = N 139.5 N is Naira, the local currency in Nigeria.
+ Market value of A. cruentus = US$430 ( N60, 000) per tonne