Synergistic effects of organic and inorganic based fertilizers on soil, leaf chemical properties and growth performance of Cola nitida

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1 IJAAR 3 (2015) ISSN Synergistic effects of organic and inorganic based fertilizers on soil, leaf chemical properties and growth performance of Cola nitida Adejobi, Kayode Babatunde Cocoa Research Institute of Nigeria, P. M. B. 5244, Ibadan, Nigeria. jobikayode@jmail.com. Article History Received 03 February, 2015 Received in revised form 04 March, 2013 Accepted 10 March, 2015 Key words: Kola seedlings, Fertilizers, Growth performance. Article Type: Full Length Research Article ABSTRACT Nursery experiment was conducted at Cocoa Research Institute of Nigeria (CRIN) Ibadan, Nigeria; to study synergistic effect of organic and in-organic based fertilizer on soil, leaf chemical properties and growth performance of kola (Cola nitida) seedlings. Combined effect of human urine (HU), kola pod husk ash (KPHA), goat dung (GD) and urea were investigated at application rates of 400 ml HU + 5 t/ha KPHA, 400 ml HU + 20 t/ha GD, 400 ml HU + 5 t/ha KPHA + 5 t/ha GD, 400 ml HU + 5 t/ha KPHA + 10 t/ha GD, 400 ml HU + 5 t/ha KPHA + 15 t/ha GD, 400 ml HU + 5 t/ha KPHA + 20 t/ha GD, 400 kg/ha urea, and the Control plot given eight treatments and were arranged in completely randomized design (CRD) with three replicates. From the results obtained, the test soil was acidic and low in organic matter (OM), N, P, K, Ca, Mg and Na. While kola pod husk ash had highest ph value and P, but goat dung had higher organic matter (OM) when compared with KPHA treatment. Also, the results obtained show that combined application of 400 ml HU + 20 t/ha GD increased significantly (p<0.05) the plant height, number of leaves, shoot length, fresh shoot weight, soil ph, OM, K, Na and leaf P, K, Ca and Na of kola seedlings relative to urea treatment and the control. While the three organic materials applied at the rate of 400ml HU + 5t/ha KPHA + 15t/ha GD, had significant (P<0.05) complimentary effect on kola seedlings number of leaves, stem girth, leaf area, root length, dry root weight, soil ph, OM, K, Mg, Na and leaf N, K, Ca, compared with urea treatment and the Control BluePen Journals Ltd. All rights reserved INTRODUCTION Kola is a tree of tropical rain forest and a member of the family Sterculiaceae (Opeke, 2005). About 40 kola species have been described in West Africa, however, the kola species of economic importance in Nigeria are Cola nitida and Cola acuminata (Daramola, 1978). The use of the kola nut; like coffee berry and tea leaf, appears to have ancient origins. It is chewed in many West African cultures, individually or in social settings, to restore vitality and ease hunger pains. Kola nuts are an important part of the traditional spiritual practice of the culture and religion in West Africa, particularly in Niger and Nigeria (Aina, 2004). Kola nuts are used as a religious object and sacred offering during prayers, ancestors veneration and significant life events, such as naming ceremonies, weddings and funerals. They are also used in traditions divination system called obi divination (Epega, 2003) Nigeria is the leading world producer of kola nut. It is estimated that Nigeria currently produces 70% of the world kola nuts with annual production of 200,000 metric tonnes of fresh nuts (Asogwa et al., 2012), although only 10% of this amount is exported, the rest is consumed locally. In spite of the immense benefits of kola, many factors have been limiting its production in Nigeria. Among these factors are poor agronomic practices, ageing kola farms (Adebiyi et al., 2011), partial and total

2 Int. J. Adv. Agric. Res. 19 sterility, inefficient natural pollination, field and storage pest and diseases (Daramola, 1978) and poor soil fertility (Asogwa et al., 2011). Willian et al. (1991) reported that because of the high rainfall, soil of humid tropics are usually leached to the extent that they contain lower level of plant nutrient than those from dryer regions and because alkaline substances (Ca, Mg, K and Na) are leached out, tends to be acidic in nature. It has also been reported that Nigeria soils are largely deficient in major essential soil nutrients, hence multiple nutritional deficiencies and lower yield are common occurrence (Agboola and Sobulo, 1981). Effort to increase the soil nutrient status through the use of chemical fertilizers by farmers is rather limited due to high cost of fertilizers and/or their poor availability to farmers locally. Thus there is need to identify locally available organic fertilizers which can be used to improve the fertility of the soil used in raising kola seedling in the nursery which usually takes about 8 to 12 months (prenursery and nursery proper). Recent research on fertilizer has reviewed the potentials of some organic fertilizers as cheap, readily available, affordable, and adoptable. The use of animal and crop wastes in form of farm yard manure (FYM) or compost is common practices in majority of the farm communities. Several studies have shown that ash derived from cocoa pod husk, saw dust and oil palm bunch waste increased availability of nutrients in the soil and consequently enhanced growth performance of the crops such as coffee, maize, cassava and vegetable (Ojeniyi, 2010; Adejobi et al., 2011). Also, the importance of plant nutrients content in human waste such as urine has never been realized as an alternative source of fertilizer for raising kola seedling in the nursery. However, there is paucity of information on the combine use of different levels of human urine (HU), goat dung (GD) and kola pod husk ash on growth performance of kola seedlings and chemical properties of kola soil. The use of these wastes will assist in environmental sanitation and nutrient recycling in both farms and urban communities. The objective of this study therefore was to evaluate the combine effects of human urine, goat dung and kola pod husk ash on the chemical properties of soil and growth performance of young kola seedlings in the nursery. MATERIALS AND METHODS Experimental location The trial was conducted at the experimental plot of Cocoa Research Institute of Nigeria (CRIN), Ibadan, on latitude E and longitude E in the humid tropical and rainforest zone of Nigeria. The rainfall is between mm per annum and a daily average temperature of 30.1 C. Pre-planting, soil sampling and analysis The top soil to be used for this trial was collected from 0-15 cm depth on the site and mixed thoroughly. The representative samples were taken to the laboratory, air dried and sieved with 2 mm sieve and ready for routine analysis. The soil ph (1:1 soil/water) was read on the ph meter. Organic matter was determined using wet oxidization method through Chromic Acid Digestion (Walkey and black, 1962). Soil P was extracted by Bray P extractant and the extract was developed into Murphy Blue Coloration and determined on a spectronic 20 at 882 um (Murphy and Riley, 1962). The soil K, Ca, Mg and Na were extracted with 1 M NH 4, OA ph7 and the contents of K, Ca and Na were read on the flame photometer (Jenway clinical PFP7, designed and manufactured by Jenway Ltd. Felsted Dunmow, Essex CM6 3LB, United Kingdom) while the Mg content was determine on the Atomic Absorption Spectrophotometer (Movaspec 11 visible spectrophotometer, manufactured by Pharmacia Biotech (Biochron Ltd Cambridge, England). Meanwhile, the percentage N was determined using the Microkjedahi method (Jackson, 1965). Collection, processing and chemical analysis of kola testa (KT) Kola pod husk was obtained from kola processing unit of CRIN, Ibadan. It was sun dried for a week and then burnt to ashes in the open air. After cooling the ash collected was bagged and kept in dry place before application. The goat dung was obtained from nearby pen in Akure, Ondo State. The percentage nitrogen was determined according to the method of Jackson (1965) by weighing 2 g of each organic material into a digester flask and 5 ml of H 2 SO 4, with selenium and copper sulphate tablets were added. After 5 ml of NaH was added, the distillate was collected and boric acid was added with an indicator before it was filtrated with O. I. M. HCl. Furthermore, 2 g of each organic material was weighed into a clean dry tecator digestion tubes to determine the P, K, Ca and Mg contents. Thereafter, 25 ml of HNO 3 was added down the neck of the flask and swirled to ensure that the organic material was thoroughly wetted. Five (5) ml of H 2 SO 4 and 5 ml of perchloric acid (HClO 4 ) were added and the mixture was swirled again. This was then placed at the digestion block and heated carefully by ensuring that the samples did not froth. Digestion was continued until the samples were clear and acids were completely volatized. The samples were allowed to cool and 10 ml of distilled water was added; filtration into 100

3 Adejobi 20 ml volumetric flask was done and the filtrate was left to cool before it was filled to the mark with distilled water. For phosphorus, 20 ml of phosphorus vanadomolybdate solution was added and allowed to stand for at least 2 h. The colour absorbance was measured on spectronic 20 at 442 um. Meanwhile, the percentage K, Ca and Na contents, an aliquot was measured into 100 ml flask and diluted to mark. One (1) ml of the sample solution was taken, and the flame photometer was adjusted, this was followed by the aspiration on the diluted sample solution (AOAC, 1970). The solution was read and later converted to mg/kg. The Mg content was determined using the atomic absorption spectrophotometer. Human urine was also collected from a house hold in CRIN, Ibadan. The collected urine solution was transported 3 km to the nursery where it was stored for 2 weeks and later applied to the soil. Twenty five (25) ml of urine solution was analyzed using the aforementioned methods. Experimental hypothesis Three hypotheses were tested using independent variable (X1) and dependent variables Y1 for kola seedlings. The independent variables (X1) were defined as organic materials such as Human urine/kola pod husk ash mix, human urine/goat dung manure mix, human urine/kola pod husk ash/goat dung manure mix. The dependent variable (Y1) were defined as comprising plant height, number of leaves, leave area, stem girth, number of branches, root length and shoot length and soil and leaf N, P, K, Ca and Mg, soil ph and O.M. Each null hypothesis (H o = U) was tested to determine whether significant statistical relationship existed between each dependent and the observed independent variables. The three hypotheses tested were as follows: There is no significant relationship between the organic materials and the plant height, number of leaves, stem girth, number of branches, leaf area, root length and shoot length of kola seedlings. There is no significant relationship between the organic materials and soil N, P, K, Ca, Mg, PH and O.M compositions. There is no significant relationship between the organic materials and leaf N,P, K, Ca and Mg of the kola seedlings Pre-nursery and nursery establishments In July 2010, disease free kola nuts (C. nitida) were obtained from Kola Processing Unit, CRIN, Ibadan. The nuts were planted in wooden box filled with sawdust and watered. The nuts germinated and allowed to grow in the pre-nursery for 8 months. During this period, the germinated seedlings were watered and weeds were controlled manually. The bulk soil samples (0-15 cm depth) were sorted to remove stones and plant debris and 2.5 kg of the soil was placed into the polythene bag (25 cm 13 cm). There were eight treatments in all and the rates of application were 400 ml Hu + 5t/ha KPHA, 400 ml Hu +20 t/ha GD, 400 ml Hu + 5 t/ha KPHA + 5 t/ha GD, 400 ml Hu +5 t/kpha + 10 t/ha GD, 400 ml Hu + 5 t/ha KPHA + 15 t/ha GD, 400 ml Hu + 5 t/ha KPHA +20 t/ha GD, 400 kg/ha Urea and the control (no fertilizer; no manure). All the treatments were replicated three times and arranged in a completely randomized design (CRD). The treatments were applied at the time the pregerminated kola nut seed was planted into each polythene bag. After four weeks of planting in the nursery, plant height, number of leaves, stem girth, number of branches and leaf area of kola nut seedlings were measured. These growth parameters were measured at every four weeks interval up to 24 weeks after planting. Weeding of site was started at 3 weeks after planting and repeated at 6, 9 and 15 weeks after planting. At the termination of the experiment (24 WAP) in the nursery, the seedlings were carefully removed from the polythene bags for the measurement of fresh root and shoot weights, root and shoot lengths. They were oven dried and thereafter dried root and shoot weights were taken before finally analyzed for N, P, K, Na, Ca and Mg contents. Post planting soil sample were also taken from each treatment, at the termination of the experiment, air dried and sieved for analysis of soil N, P, K, Ca, Mg ph, and O. M. Statistical analysis The growth data collected were analyzed using SAS software, version 2002 using ANOVA, and the treatment means were compared using the Duncan s multiple range test (p<0.05). RESULTS AND DISCUSSION Both the physical and chemical properties of the soils used for raising of kola seedlings in the nursery are presented in Table 1. According to the results of the particle size analysis, the soil was texturally sandy loam belonging to Onigambari series and alfisol (Soil Survey Staff, 1999). Based on the established critical levels for soils in South-western Nigeria, the soil was acidic with ph of 5.24 and low in organic matter (0.54%) compared to the findings of critical level of 3% organic matter (Agboola and Corey, 1976). In addition the total % nitrogen(0.13%)

4 Int. J. Adv. Agric. Res. 21 Table 1. Pre-planting physiochemical properties of the soil. Soil properties Value Physical properties Sand g/kg Silt g/kg Clay g/kg Textural class sandy loam Chemical properties ph (H 20) 1:1 1.32g/kg Organic Carbon 5.24 Organic Matter 0.54% Total Nitrogen 0.13g/kg Available Phosphorous 2.02mg/kg Exchangeable bases K cmol/kg Ca cmol/kg Mg cmol/kg Na cmol/kg Mn cmol/kg Exchangeable acidity Al cmol/kg H cmol/kg ECEC 4.27 cmol/kg Table 2.Chemical analysis of human urine (HU), kola pod husk ash (KPHA) and goat dung (GD) used as organic fertilizers. Treatments ph [H2O (1:1)] C/N OM (%) N (%) P (mg/kg) K Ca Mg Na Human urine kola pod husk ash (KPHA) Goat dung(gd) was found to be less than 0.15% N, which is considered as the optimum for most crops including kola (Sobulo and Osiname, 1981). While the available P (2.02 mg/kg) was less than 10 mg/kg P, which is considered as adequate for the production of crops (Agboola, 1982). The exchangeable K and Mg (0.52 and 2.39 cmol/kg) were higher than the critical levels of 0.2 and 0.9 cmol/kg which were considered optimal for most crops (Agboola and Corey, 1976). Among the organic residues used, kola pod husk ash (KPHA) had the highest ph (8.21 ) and P (32.62) followed by human urine (6.80) while goat dung had the lowest ph and P of (6.38) and (16.36) respectively (Table 2). In particular human urine had the highest N, K, Ca and Na concentrations and this was followed by kola pod husk ash. The goat dung was indicated to be fairly high in NPK and Ca (Table 2). Relative higher N obtained from kola pod husk ash could be attributed to the fact that kola pod husk could be a good N source to that extent that volatilization of N during burning could not reduce it N content to a critical level of 0.15% required for most crops. The plant height, number of leaves, stem girth, number of branches, leaf area, root and shoot, weight of kola seedlings under different organic fertilizers are presented in Tables 3 and 4. The results show that combined application of 400 ml HU + 20 t/ha GD increased significantly (p<0.05 ) the plant height, number of leaves, number of branches, shoot length, and fresh shoot weight of kola seedlings relative to urea treatment and the control. While combined application of 400 ml HU +5 t/ha KPHA + 15 t/ha GD gave significant higher stem girth, leaf area, and dry root weight relative to the urea fertilizer treatment and the control. This study has shown that human urine, goat dung and kola pod husk ash, seemingly waste products of man, animal and plant respectively could be used as fertilizers to increase

5 Adejobi 22 Table 3.Effects of different levels of HU and KPHA on growth parameters of kola seedlings in the nursery. Treatments Plant height Number of leaves Stem girth Number of branches Leaf area Root length Shoot length 400 ml HU+5 t/ha KPHA 32.74ab 15.16bdc 0.97ab 3.58ab 42.66b 28.50ab 39.16ab 400 ml HU+20 t/ha GD 38.27a 21.44ab 0.94ab 4.35a 41.01b 19.93b 45.90a 400 ml HU+5 t/ha KPHA+5t/ha GD 34.79ab 13.83dce 0.87ab 3.14ab 39.31b 30.83a 39.33ab 400 ml HU+5 t/ha KPHA+10t/ha GD 33.65ab 8.29e 0.83ab 2.72ab 55.32ab 19.43b 29.00b 400 ml HU+5 t/ha KPHA+15t/ha GD 35.70ab 17.77abc 1.03a 3.76a 64.22a 29.80a 39.73ab 400 ml HU+5 t/ha KPHA+20t/ha GD 35.88ab 21.66a 1.01a 3.70a 58.19ab 28.90ab 40.83ab 400 kg/ha urea 28.56b 9.73de 0.76b 1.89b 44.51b 30.04ab 34.47b Control 28.09b 13.66de 0.80b 2.00b b 29.77b Mean of treatments within each column followed by the same letters are not significantly different from each other. Table 4. The yield parameters of kola seedlings 24 weeks after planting under different levels of fertilizers. Treatments Fresh root (g) Dry root (g) Fresh shoot (g) Dry shoot (g) 400 ml HU+5 t/ha KPHA 12.76ab 4.64b 20.28ab 8.20abc 400mlHU+20 t/ha GD 9.58b 4.91b 32.13a 11.55ab 400mlHU+5 t/ha KPHA+5 t/ha GD 12.17ab 4.55b 15.15bc 6.79be 400mlHU+5 t/ha KPHA+10 t/ha GD 6.56b 5.76b 7.27b 3.45b 400mlHU+5 t/ha KPHA+15 t/ha GD 14.43ab 8.10a 23.32b 10.10abc 400mlHU+5 t/ha KPHA+20 t/ha GD 21.53a 5.81b 27.64ab 13.86a 400kg/ha urea 22.83a 5.49b 21.90b 6.74bc Control 16.43ab 7.05b 24.46b 10.67ab Mean treatments within each column followed by the same letters are not significantly different from each other. availability of N, P, K, Ca and Mg in the soil, and their uptake by kola plants thereby leading to enhanced growth performance of kola. This result attests to the synergistic relationship that exists among the amended organic manures and their resultant complimentary effect in enhancing vegetative growth of kola seedlings. The current result is consistent with the findings of Ayeni (2010) who reported that cocoa pod ash combined with NPK 15:15:15 fertilizers significantly (p<0.05) gave the highest fruit yield of tomato. Similarly, Makinde (2010) found out that vegetative growth of crops was engendered by organic manure especially kola pod husk, cocoa pod husk and NPK fertilizer. Also, Upreti (2011) observed that the crops yield (potato, rice, radish onion and wheat) increases when urine is applied in split and efficacy of urine increases with the supplement dose of phosphorus (P) and potash (K) from chemical fertilizers to increase yield of different crops as compared to urine applied in single dose at the time of planting. The poor growth of the kola seedlings in the nursery under the control treatment was consistent with the low nutrient status of soil N, P, Mg, OM and ph, this fact is supported by Agboola (1982) who had identified poor soil fertility as the moving factor in reducing crop yields. This observation was also corroborated with the work of Moyin-Jesu (2008) which identified deficiency symptoms of yellow coloration, purple coloration and marginal burning of leaves signifying N, P, K deficiencies in tropical Africa soils. Effects of both organic and inorganic fertilizers applied on post-planting physiochemical properties of the soil are presented in Table 5. Different organic fertlizers applied increased significantly (P<0.06). The soil ph, OM, N, P, Mg compared to the control (Table 5). This observation did not deviate from the works of Ojeniyi and Adejobi (2002). Swift and Anderson (1993) reported that organic manure increased soil N, OM, P, K and PH, and also micronutrients which are absent in conventional N, P, K 15:15:15 fertilizer. The significant increase in soil ph by the use of 400 ml Hu + 5 t/ha KPHA and 20 t/ha GD compared to other treatments was traced to its high K and Ca as a result of the synergy among the amended organic manure and could be effective as liming materials. The soil PH had been reported to influence nutrient uptake and available to crops for optimum growth (Gordon, 1988). Meanwhile the NPK fertilizer gave the best value of soil N as compared to other treatments and

6 Int. J. Adv. Agric. Res. 23 Table 5. Post-planting physiochemical properties of the soil. Treatments Soil ph (H2O) 1:1 OC (g/kg) OM (%) N (%) P (mg/kg) K Ca Mg Na 400 ml HU+5 t/ha KPHA 6.93c 1.40b 2.41b 1.12b 17.05a 0.59b 4.31ab 1.50ab 0.40ab 400 ml HU+20 t/ha GD 7.12b 2.04ab 3.50a 2.18a 8.65f 0.88a 3.50d 1.20c 0.37b 400 ml HU+5 t/ha KPHA+5 t/ha GD 7.13b 2.01ab 3.47a 1.17b 10.29d 0.41c 4.60a 1.40ab 0.45ab 400 ml HU+5 t/ha KPHA+10 t/ha GD 6.53d 3.27a 2.77b 1.14b 10.33d 0.42c 4.00bc 1.50ab 0.65a 400 ml HU+5 t/ha KPHA+10 t/ha GD 6.55d 1.97ab 3.40a 2.17a 13.41c 0.46c 3.90c 1.80a 0.39b 400 ml HU+5 t/ha KPHA+20 t/ha GD 7.36a 2.05ab 3.53a 2.18a 4.12g 0.11e 2.90e 1.30bc 0.13d 400 kg/ha Urea 6.01e 2.53ab 1.36c 2.22a 13.69b 0.32d 4.30ab 1.60ab 0.33c Control 5.96f 2.78ab 0.51d 0.89c 9.57e 0.30d 3.80cd 1.00c 0.27cd Means of treatments within each column followed by the same letters are not significantly different from each other. Table 6.Leaf chemical composition after 24 weeks of treatment application. Treatments N (%) P (Mg/kg) K Mg (Cmo;/kg) Ca Na 400 ml HU+5 t/ha KPHA 2.25bc 46.13a 4.86c 32.00a 36.00dc 1.59b 400 ml HU+20 t/ha GD 2.88a 29.99bc 8.64a 18.59c 68.88a 0.49d 400 ml HU+5 t/ha KPHA+5 t/ha GD 2.60a 19.21d 5.54b e 1.74a 400 ml HU+5 t/ha KPHA+10 t/ha G 2.74a 19.29d 7.77a 25.00b 57.56a 0.55c 400 ml HU+5 t/ha KPHA+10 t/ha GD 2.39b 18.12d 7.45a 18.81c 45.26b 0.40f 400 ml HU+5 t/ha KPHA+20 t/ha G 2.78a 21.05cd 4.82c 32.00a 60.00a 0.50d 400 kg/ha Urea 2.15bc 19.47d 4.04d 33.33a 40.71c 0.41ef Control 0.04d 7.17e 2.67e 7.25d 3.36e 0.21g Mean of treatments within each column followed by the same letters are not significantly different from each other. control. The leaf analysis of the kola seedlings for different organic fertilizer sources is presented in Table 6. The results showed that there were significant increases (P<0.05) discovered in the leaf N, P, K, Ca, Mg contents as compared to the control. 400 ml HU+ 20 t/ha GD increased the kola leaf N, K and Ca contents compared to the NPK fertilizer and the control; however, 400 ml Hu + 5 t/ha KPHA was found to increase the leaf P more than other treatments and the control. RECOMMENDATION AND CONCLUSION Some selected organic manures and NPK fertilizers were studied in terms of their effects on soil, leaf chemical properties and growth performance of kola in the nursery. it was proved that amended form of goat dung and human urine with kola pod husk ash or without increased the soil, leaf and growth performance of the kola seedlings in the nursery. For this reason farmers are encouraged to adopt their use especially 400ml Hu + 20 t/ha GD. Combination of more than two organic sources might not be necessary. REFERENCES Adebiyi S. E., Uwagboe O., Agbongiarhuoyi E. A., Ndagi I. & Aigbekaen E. O. (2011). Assessment of agronomic practices among kola farmers in Osun State. Nigeria World J. Agric. Sci. 7(4): Adejobi K. B., Adeniyi D. O., Famaye, A. O., Adenuga O. O. & Ayegboyin K. O. (2011). Evaluation of the effectiveness of goat dung manure and kola pod husk ash on nutrient composition and growth performance of coffee (Coffea arabica) in Nigeria. J. Appl. Biosci. 44: Agboola A. A. (1982). Soiln testing, soil fertility and fertilizer use in Nigeria. A paper presented at the first nations seminar on Agricultural Land Resources, Kaduna, Nigeria. Pp Agboola A. A. & Corey R. B. (1976). Nutrient survey of maize in Western Nigeria. Nigerian. J. Sci. 10:182: Agboola A. A. & Sobulo R. A. (1981). A review of soil fertility in south Western zone of Nigeria. F. D. A. L. R. Kaduna. Report No Aina Adewale-Somadhi (2004). Practitioner s handbook for the IFA professional. Ile Orunmila Communication. P. I. ISBN Association of Official Analytical Chemist, AOAC (1970). Official method of analysis 12 th Edition. AOAC Washinton, D. C, U.S.A. Asogwa E. U., Otuonye A. H., Mokwunye F. C., Oluyole K. A., Ndubuaku, T. C. N. & Uwagboe E. O. (2011). Kola nut production, processing and marketing in the South eastern States of Nigeria. Afr. J. Plant Sci. 5(10): Asogwa E. U., Adedej A. R., Ndubuaku T. C. N., Oyedokun A. U. & Ndagi I. (2012). Strategies for improving production and storage of kola in Nigeria AM-EUR. J. Agric Environ. Sci. 12(1):37-43.

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