ISSN: International Journal of Science, Engineering and Technology Research (IJSETR) Volume 1, Issue 3, September 2012

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1 Volume 1, Issue 3, September 212 Morphological Response of Pepper under Variable Water Application Using Micro-Sprinkler System in Akure, Nigeria ¹Alao, F., ¹Alatise, M. O. and ²*Oloruntade, A. J. ¹ Department of Agricultural Engineering, Federal University of Technology, Akure, Nigeria ² Department of Agricultural Engineering Technology, Rufus Giwa Polytechnic, Owo, Nigeria Abstract Morphological response of pepper (Capsicum annum) under variable water application was examined during two off-seasons of 27/8 and 28/9 at the Agricultural Engineering Research Farm of the Federal University of Technology, Akure, Nigeria. In order to effectively ascertain the changes that have occurred, the crop was irrigated using micro-sprinkler system that allowed three treatments 1, 2, 3 at. WR (water requirements) of pepper,.7 WR, and 1 WR respectively. The experiment was repeated twice and irrigation was carried out at 3-day interval. Measurements of morphological features were made to include number of leaf, leaf area, plant height and stem diameter. The results showed high correlation (R 2 ranges between.97 to.92 in 27/28 season) between plant height and number of leaf and between plant height and leaf area (R 2 ranges between.98 to.9 in 27/28 season). Similar high correlation values were also recorded for leaf area and number of leaf and plant height and stem diameter. Variations in irrigation treatments were observed to have had differences in morphological changes in pepper which is capable of affecting fruiting. Consequently, we recommend further investigation into the possibility of monitoring water use efficiency with changes in morphological features of pepper to ensure optimum irrigation water use. Index Terms - leaf area, number of leaf, plant height, stem diameter. I. INTRODUCTION In view of the prevailing and projected future climatic conditions which have the tendency to cause water shortage all over the world, operators of irrigation facilities should strive for effective water use. According to recent findings, current trends indicate that several regions of the world are facing water shortages and this is more noticeable in the developing countries where balancing of the demand and supply of water to ensure self-sufficiency in agriculture has become a serious economic stalemate [1, 2]. It, therefore, follows that without water-saving agricultural measures, meeting the world food requirements in the future with the declining and limited clean water reservoirs as 7% ~ 9% of the available water resources is used in food production, would be much difficult [2]. Although rapid growth and ultimately high yields can be obtained with irrigation for most crops, such a practice should be well scheduled because the quantity of water needed at different stages of crop growth differ. It has been stated by [3] that plant monitoring can be one of the most visible methods of determining when to irrigate, since the primary objective of irrigation is to provide crops with water when they need it. Thus, appearance and growth, leaf water potential and stomata resistance are some important plant indicators for water stress in pepper [3]. Whereas inadequate water supply at the early stage of crop establishment can lead to poor vegetative growth and thus low yield, excessive irrigation water supply may also cause weedy growth and lodging thereby leading to poor quality harvests and difficulty in mechanical harvesting of pepper. Pepper (Capsicum annum) is one of the varied and widely used foods in the world. The crop is one of the vegetable crops commonly grown in China, USA, East Indies, Korea, and many other countries, because of the nutritional value of its fruits, which are an excellent source of antioxidant All Rights Reserved 212 IJSETR 1

2 Volume 1, Issue 3, September 212 compounds and natural colors, like carotenoids and vitamin C [4-7]. Its production has been on the increase all over the world in recent years [8], perhaps as a result of its economic significant in the world market [9]. Yet, Nigeria is known to be one of the major producers of pepper in the world accounting for about % of the African production [1]. This implies that available soils and weather conditions in the country can readily support the growth and production of pepper [1]. In general, pepper grows well on a wide range of soil types, on the other hand, adherence to good drainage ensures good harvest. In order to maintain good drainage, preparation of soil should be done to good tilt and a soil ph of. 7. is desirable. Where manure is applied, it is worked into the soil during preparation for planting. Application of fertilizer, such as N.P.K 1-3-1, at the rate of kg per 3 square meters is suitable for improved yield. Onethird of the application is carried out at transplanting, one-third when flowers form, and one-third a month after flowering. Additional nitrogen may be applied after the first harvest to improve fruit size and vigour, but excess nitrogen applied too early may cause flower drop [11]. Despite the highly favourable conditions for the production of pepper in Nigeria, the crop is majorly grown in the Northern part of the country under traditional method of irrigation using watering cans. However, the crop has the tendency to earn additional foreign exchange for the country since pepper grown in Nigeria is in high demand because of its pungency and good flavour [8]. Hence, there is the need to encourage widespread cultivation of pepper throughout the country especially with good irrigation technique to meet local needs and also have excess for export, moreso that full irrigation has the potential to generate highest net income for farmers [1]. In recognition of this and as a result of the tropical humid climate of the South-Western Nigeria where this study was carried out, sprinkler irrigation systems was adopted. Sprinkler irrigation systems apply water directly to the surface of the crop as well as the soil around the roots of the crop with high efficiency, thereby reducing water loss, ponding and flooding. It has been reported by [12] in their studies that sprinkler irrigation systems reduce the water use of crop by about % compared to that under seepage system. Although the results of the effects of variable water application on yield and some quality parameters of pepper have earlier been rendered [11, 13], we find it appropriate to report on the morphological response of pepper to variable water application under micro-sprinkler system since morphological growth and yield are related and can help in determining appropriate irrigation scheduling and ensure water use efficiency. II Materials and Methods The study was carried out at the Research Farm of the Department of Agricultural Engineering, Federal University of Technology, Akure, in the South-Western part of Nigeria (Latitude 7 16' N; longitude 13' E) and lies within the tropical humid climate with two distinct seasons. Akure is relatively dry from November to March and wet from April to October with annual rainfall range of 14 mm 24 mm of which raining season accounts for 9% and the month of April signals the commencement of rainfall. The field experiment was conducted during 27/8 and 28/9 dry seasons respectively. The physical and chemical properties of the soil were determined. The experimental design was a Randomized Complete Block Design (RCBD) with three treatments and three replicates. Each treatment was subjected to different water applications of. WR as Low,.7 WR as Medium, and 1 WR as High irrigations respectively. A 1 m x 6 m portion of the farm site was ploughed and harrowed for effective seed bed formation and 1 m x 1 m part of the ploughed land was divided into nine seed beds (micro-sprinkler plots), 2. m long, 2. m wide and.1 m deep and leaving. m spacing between beds. The micro-sprinklers were installed at the centers of the nine 2. m x 2. m plots. Each treatment plot was connected to separate supplies (.1 m 3 capacity reservoirs) placed adjacent to each of the beds at uniform pressure head of 1. m to ensure even distribution of water. The soil in the area was generally sandy-loam with ph range of.9-6.4, rich in organic matter and important macro nutrients while the bulk density taken within.3 m depth of soil was 1.2g/cm³. III Experimental Design An area of 1 m x 6 m portion of the farm site was ploughed and harrowed for effective seed bed formation and All Rights Reserved 212 IJSETR 2

3 ISSN: Volume 1, Issue 3, September m x 1 m part of the prepared land was divided into nine seed beds (micro-sprinkler plots), 2. m long, 2. m wide and.1 m deep and leaving. m spacing between beds. The micro sprinklers were installed at the centers of the nine 2. m x 2. m plots with three treatments replicated three times in a randomized complete block design. Each treatment plot was connected to separate supplies (.1 m 3 capacity reservoirs) placed adjacent to each of the beds at uniform pressure head of 1. m. Treatments were based on different percentage of water requirements (WR) of pepper as % WR, 7% WR, and 1% WR. Irrigations were carried out at three day intervals and the volume of water applied in each treatment was monitored. Rainfalls were measured during the experiment with the aid of automated rain gauge. Pepper seeds were transplanted manually after six weeks in nursery seedbeds at a spacing of 4 cm x 6 cm between. IV RESULTS AND DISCUSSION 4.1 Relationship between Number of Leaf and Plant Height Figure 4.13 shows the relationship between the number of leaf and the plant height under low irrigation in 27/8 dry season. The coefficient of determination R² was This shows that there is a good correlation between the number of leaf and their corresponding heights with time. Similar patterns are also recorded in the relationship between number of leaves and plant height under medium and high irrigation treatments with coefficients of determination R² of.934, and.9241 as shown in Figures and, respectively. Likewise, the coefficients of determination in 28/9 season (not shown) were.9872,.93, and.9748 for low, medium, and high irrigation treatments, respectively y =.121x R 2 = Plant height 6 (cm) y =.1494x R 2 = Figure 4.1: Changes in plant height with number of leaves under low, medium and high irrigation treatments in 27/8 season. 4.2 Relationship between Leaf Area and Plant Height Figure 4.1 shows the relationship between the leaf area with plant height under low irrigation treatment in 27/8 with a coefficient of determination R² of.948. Similar results were also recorded under medium and high irrigation treatments as shown in Figures and, while their respective corresponding coefficients of determination R² were.982, and Likewise, the coefficients of determination in 28/9 season (not shown) were.929,.8712, and.9736 for low, medium, and high irrigation treatments respectively. y =.132x R 2 = Number of leaves All Rights Reserved 212 IJSETR 3

4 ISSN: Volume 1, Issue 3, September y =.7x R 2 = was compared with the number of leaf under medium and high irrigation treatments, the coefficients of determination.939, and.943 shown in Figures and, respectively were obtained. Similarly, the pattern also repeated itself in 28/9 season (not shown) as coefficients of determination were found to be.936,.9423, and.8874 for low, medium, and high irrigation treatments, respectively. 2 y =.84x R 2 = y = 8.439Ln(x) R 2 = y = 9.812Ln(x) R 2 = y = 9.918Ln(x) R 2 = y = Ln(x) R 2 =.9438 Figure 4.2: Changes in leaf area with plant height under low, medium and high irrigation treatments in 27/8 season. 4.3 Relationship between Leaf Area and Number of Leaf Figure 4.3 shows the relationship between the leaf area and the number of leaf under low irrigation treatment with a coefficient of determination R² of.99. When the leaf area Figure 4.3: Changes in leaf area with number of leaves under low, medium and high irrigation treatments in 27/8 season. All Rights Reserved 212 IJSETR 4

5 ISSN: Volume 1, Issue 3, September Relationship between Plant Height and Stem Diameter Figure 4.4 shows the relationship between the plant height and the stem diameter under low irrigation treatment with a coefficient of determination of Under medium and high irrigation treatments, similar patterns were established in the comparison of the plant height and the stem diameter with their coefficients of determination R 2 also recorded as.999 and.9999, respectively as shown in Figures and. The highest coefficient of determination was obtained under high irrigation treatment which suggests that pepper plant utilized to the fullest irrigation water for combined growth in terms of height and stem diameter. Likewise, the coefficients of determination in 28/9 season (not shown) were.998,.869, and.87 for low, medium and high irrigation treatments, respectively y = 4.81x R 2 = y = 2.417x R 2 =.999 Stem diameter (cm) Stem diameter (cm) y = x R 2 = Stem diameter (cm) Figure 4.4: Changes in plant height with stem diameter under low, medium, and high treatments in 27/8 season V Discussion irrigation Deumier in [14] observed that excessive irrigation can have negative impacts on quantitative and qualitative yields of pepper, it follows therefore that irrigation should be properly scheduled to avoid water stress and waste. Response of morphological features of pepper to water supply can serve as a means of identifying whether applied water is being properly used by plant and as well helps to evolve appropriate irrigation scheduling for optimum use of water. From the results of the study, it was observed that pepper responded positively to water application as seen in changes in plant morphological features. Number of leaf, leaf area, plant height and diameter, all responded positively, suggesting that the features have the potential to act as determinants for identifying water stress in pepper plants. We further observed a corresponding increase in height with stem diameter which is in agreement with the findings of [1, 16]. Whereas excessive canopy formation could pose serious problem where mechanical harvesting of pepper is intended, wider canopy diameters have been found to produce more fruits (pods) due to increased number of secondary and tertiary branches which serves as sites for fruit bud formation [17]. However, to avoid lodging it is important to pursue a growth system which ensures a lower height/diameter ratio and excessive vegetative growth in pepper plant should be avoided since smaller surface area can contribute to reducing All Rights Reserved 212 IJSETR

6 Volume 1, Issue 3, September 212 water consumption [18]. Favourable vegetative growth according to [19] can ensure reproductive balance in crop production. Hence, water supply should be carried out to ensure balance amongst all contending issues in pepper production to avoid over-irrigation while ensuring optimum yield of crop. II. CONCLUSION The research was conducted to ascertain the morphological response of Capsicum annum to water application under micro sprinkler irrigation system. Variations between plant height and number of leaves for treatments 1, 2, and 3 have coefficient of determination of.97,.93, and.92 in 27/8 season, also,.99,.9 and.97 in 28/9 season, while the R² values for treatments 1, 2, and 3 for the relationship between plant height and stem diameter were.99,.99 and.99 in 27/8, also,.99,.87 and.88 in 28/9 seasons, respectively. Hence, it can be concluded that morphological features of pepper responded to variable water application which suggests that pepper plant utilized irrigation water for all-round growth that might also positively affect yield of the crop since good vegetative growth can enhance increased fruiting. However, since excessive vegetative growth might lead to lodging and also affect output, therefore, there is the need to strike appropriate balance amongst the various issues in water application in pepper production. Hence, we recommend further investigation into the possibility of evolving appropriate irrigation scheduling through the monitoring of morphological changes in pepper plant to ensure optimum irrigation water use. REFERENCES [1] S. M. Sezen, A. Yazar, S. Tekin, S. Eker and B. Kapur, Yield and quality response of drip-irrigated pepper under Mediterranean climatic conditions to various water regimes, African Journal of Biotechnology, Vol. 1 (8), pp , Feb [2] I. F. Tarawalie, X. Wengang, S. Guangcheng and H. Chunli, Effect of water use efficiency on growth and yield of hot pepper under partial root-zone drip irrigation condition, International Journal of Scientific & Engineering Research, 3 (1): 1-14, Jan [3] F. Alao, Yield-Water Use Evaluation for Pepper Production under Irrigated Condition in Akure, M. Eng. Thesis, Federal University of Technology, Akure, Nigeria, June, 211. [4] L. R. Howard, S. T. Talcott and C. H. Brenes, Changes in phytochemical and antioxidant activity of selected pepper cultivars (Capsicum species) as influenced by maturity, J. Agric. Food Chem., 48: , 2. [] V. Russo and L. Howard, Carotenoids in pungent and non-pungent peppers at various developmental stages grown in the field and glasshouse, J. Sci. Food Agric., 82: , 22. [6] J. M. Navarro, P. Flores and C. Garrido, Changes in the contents of antioxidant compounds in pepper fruits at different ripening stages, as affected by salinity, Food Chem., 96: 66-73, 26. [7] G. C. Shao, Z. Y. Zhang and N. Liu, Comparative effects of deficit irrigation (DI) and partial root zone drying (PRD) on soil water distribution, water use, growth and yield in greenhouse grown hot pepper, Sci. Hortic. 119: 11-16, 28. [8] O. O. Idowu-agida, E. I. Nwaguma and I. B. Adeoye, Cost implication of wet and dry season pepper production in Ibadan, Southwestern Nigeria, Agriculture and Biology Journal of North America, 1(4):49-, 21. [9] G. Ozuzounido, I. Ilias, A. Giannakoula, and P. Papadopoulou, Comparative Study on the Effects of Various Plant Growth Regulators on Growth, Quality and Physiology of Capsicum annuum L, Pakistan Journal of Botany, 42 (2): 8-814, April, 21. [1] Businessday, Producing pepper for export market 27, [11] F. Alao, A. J. Oloruntade and K. O. Mogaji, Yield quality response (YQR) of pepper under variable water application using micro-sprinkler system, Int. Journal of Agronomy and Agricultural Research, Vol. 2, No. 6, p , June, 212. [12] D. J. Pitts and G. A. Clarke, Comparison of drip irrigation to sub- irrigation for tomato production in All Rights Reserved 212 IJSETR 6

7 Volume 1, Issue 3, September 212 southwest Florida, Applied Agric. Engineering 7 (2): , [13] Y. Olotu, F. Alao, and C. J. Odighi, Yield-Crop Water Use (Cwu) Evaluation for Pepper Production under Irrigated Cultivation in Akure, Nigeria, Global Journal of Science Frontier Research Agriculture & Biology, Vol. 12 (1): , Jan [14] J. M. Deumier, P. Leroy and P. Peyremorte, Tools for improving management of irrigated agricultural crop systems. In: Irrigation Scheduling; from Theory to Practice, Proceedings of ICID/FAO Workshop, Sept., 199, Rome. Water Report No. 8, FAO, Rome, [1] P. Rudall, Anatomy of Flowering Plants: An introduction to Structure and Development, 2nd Edition, Cambridge University press, Cambridge, pp: 48, [16] G. O. Nkansah, A. Ayarna and T. J. Gbokie, Morphological and Yield Evaluation of Some Capsicum Pepper Lines in Two Agro-Ecological Zones of Ghana, Journal of Agronomy, 1 (3): 84-91, 211. [17] A. Orak and N. Ilker, Agronomic and morphological characters of some common Vetch (Viciasativa L.) genotypes under trakaya region conditions, Journal of Agronomy, 3: 72-7, 24. [18] S. Bañón, A. González, E. A. Cano, and J. A. Franco, Growth, development and colour response of potted Dianthus caryophyllus cv. Mondriaan to paclobutrazol treatment, Sci. Hort., 94: , 22. [19] G. C. Shao, R. Q. Guo, N. Liu, S. E. Yu and W. G. Xing, Photosynthetic, chlorophyll fluorescence and growth changes in hot pepper under deficit irrigation and partial root zone drying, African Journal of Agricultural Research Vol. 6 (19), pp , Sept All Rights Reserved 212 IJSETR 7