Differential Biomass Accumulation among African Leafy Vegetables as Affected by Wastewater Irrigation in Kitui County, Kenya

Main Article Content

Judy Mwende Wambua
Shadrack Ngene
Nicholas K. Korir
Winnie Ntinyari
Joseph P. Gweyi-Onyango


Water scarcity of fresh water in Sub-Saharan has led to utilization of the wastewater in home gardening and also in commercial production of vegetables. Wastewater is associated with various substances including nutrients and heavy metals hence it is pertinent to evaluate its effects on growth and yield of vegetables. An experiment was conducted to evaluate the effect of waste water released from the municipal council on the biomass accumulation in African leafy vegetables. Field experiments were carried out in two seasons and one greenhouse experiment. The field trial was laid out in a Randomized Complete Block Design (RCBD) and in the greenhouse the treatments were arranged in Complete Randomized Design (RCD) replicated three times. Four leafy vegetables were the treatments replicated three times. The vegetables were irrigated with waste water. Plant samples were collected at 6 WAP and 12 WAP, partitioned and dried in an oven and later weighed using electronic weighing balance. The findings revealed differences in biomass accumulation into various organs. Black nightshade depicted the highest leaf dry matter in the greenhouse at both 6 weeks after plant (WAP) and 12 WAP (24.62 g and 81.12 g respectively). Cowpea showed the highest increment (7 folds) in leaf weight between 6 to 12 WAP as compared to was paltry 3.6 folds. The highest stem dry weight was obtained in the amaranth species at 6 WAP and 12 WAP both in the greenhouse; recording 32.59 g and 90.12 g respectively. A similar trend was noted in root dry weight and root: shoot ratio. Cowpea had the least biomass accumulation potential across all the parameters in both seasons and in the greenhouse. The increased biomass growth is an indication sufficient availability of nutrient that promoted vibrant plant growth and also less toxicity from the heavy metals. Therefore, waste water can be put into use to enhance improved productivity of African leafy vegetables.

Nutrient benefits, plant growth, heavy metals

Article Details

How to Cite
Wambua, J., Ngene, S., Korir, N., Ntinyari, W., & Gweyi-Onyango, J. (2019). Differential Biomass Accumulation among African Leafy Vegetables as Affected by Wastewater Irrigation in Kitui County, Kenya. International Journal of Plant & Soil Science, 27(6), 1-7. https://doi.org/10.9734/ijpss/2019/v27i630095
Original Research Article


Graham RD, Welch RM, Bouis HE. Addressing micronutrient malnutrition through enhancing the nutritional quality of staple foods. Principles, Perspectives and Knowledge Gaps; 2001.

Dube P, Heijman WJ, Ihle R, Ochieng J. The potential of traditional leafy vegetables for improving food security in Africa. In Establishing Food Security and Alternatives to International Trade in Emerging Economies. 2018;220-243. IGI Global.

Raschid-Sally L, Jayakody P. Drivers and characteristics of wastewater agriculture in developing countries. Results from a Global Assessment. 2009;127. IWMI.

Gweyi-Onyango JP, Osei-Kwarteng M. Safe vegetable production with wastewater in developing countries: Demystifying negative notions. African Journal of Horticultural. Sci. 2011;5:70-83.

Ensink JH, Mahmood T, Dalsgaard A. Wastewater‐irrigated vegetables: Market handling versus irrigation water quality. Tropical Medicine & International Health. 2007;12:2-7.

Khaled SB, Muhammad AS. Field accumulation risks of heavy metals in soil and vegetable crop irrigated with sewage water in Western Region of Saudi Arabia. Saudi Journal of Biological Sciences. 2015;23:32-44.

Mireri C, Atekyereza P, Kyessi A, Mushi N. Environmental risks of urban agriculture in the Lake Victoria drainage basin: A case of Kisumu municipality, Kenya. Habitat International. 2007;31(3-4):375-386.

Mohammed SA, Folorunsho JO. Heavy metals concentration in soil and Amaranthus retroflexus grown on irrigated farmlands in the Makera Area, Kaduna, Nigeria. Journal of Geography and Regional Planning. 2015;8(8):210-217.

Stoltz E, Greger M. Accumulation properties of As, Cd, Cu, Pb and Zn by four wetland plant species growing on submerged mine tailings. Environmental and Experimental Botany. 2002;47(3):271-280.

Wallace JS. Increasing agricultural water use efficiency to meet future food production. Agriculture, Ecosystems & Environment. 2000;82(1-3):105-119.

Anwar S, Nawaz MF, Gul S, Rizwan M, Ali S, Kareem A. Uptake and distribution of minerals and heavy metals in commonly grown leafy vegetable species irrigated with sewage water. Environmental Monitoring and Assessment. 2016;188(9): 541.

Zu YQ, Sun JJ, He YM, Wu J, Feng GQ, Li Y. Effects of arsenic on growth, photosynthesis and some antioxidant parameters of Panax notoginseng growing in shaded conditions. Int J Adv Agric Res. 2016;4:78-88.

Nagajyothi PC, Dinakar N, Suresh S, Udaykiran Y, Suresh C, Damodharam T. Effect of industrial effluent on the morphological parameters and chlorophyll content of green gram (Phaseolus aureus Roxb). J. Environ. Biol. 2009;30(3):385-388.

Torabian A. Effect of urban treated sewage on yield and yield components of sweet pepper. Plant Ecophysioly. 2010;2:97-102.

Hussein AHA. Impact of sewage sludge as organic manure on some soil properties, growth, yield and nutrient contents of cucumber crop. Journal of Applied Sciences. 2009;9(8):1401-1411.

Bedbabis S, Trigui D, Ahmed CB, Clodoveo ML, Camposeo S, Vivaldi GA, Rouina BB. Long-term effects of irrigation with treated municipal waste water on soil, yield and olive oil quality. Agricultural Water Management. 2015;160:14-21.

Aronsson P, Perttu K. Willow vegetation filters for wastewater treatment and soil remediation combined with biomass production. The Forestry Chronicle. 2001;77(2):293-299.

Smith SR. A critical review of the bioavailability and impacts of heavy metals in municipal solid waste composts compared to sewage sludge. Environment International. 2009;35(1):142-156.

Uzma S, Azizullah A, Bibi R, Nabeela F, Muhammad U, Ali I, Häder DP. Effects of industrial wastewater on growth and biomass production in commonly grown vegetables. Environmental Monitoring and Assessment. 2016;188(6):328.

Shakoor SAB, Farooq MA. Effects of irrigation with waste water from different industries on vegetables grown in vicinity of Faisalabad, Pakistan; 2013.

Faizan S, Kausar S, Akhtar N. Influence of wastewater application and fertilizer use on growth, photosynthesis, nutrient homeostatis, yield and heavy metal accumulation in okra (Abelmoschus esculentus L. Moench). Pakistan Journal of Biological Sciences. 2014;17(5):630-640.

Parveen T, Mehrotra I, Rao MS. Impact of treated municipal wastewater irrigation on turnip (Brassica rapa). Journal of Plant Interactions. 2014;9(1):200-211.

Hu X, Ding Z. Lead/cadmium contamination and lead isotopic ratios in vegetables grown in peri-urban and mining/smelting contaminated sites in Nanjing, China. Bulletin of Environmental Contamination and Toxicology. 2009;82(1): 80-84.

Singh RP, Agrawal M. Use of sewage sludge as fertiliser supplement for Abelmoschus esculentus plants: Physiological, biochemical and growth responses. International Journal of Environment and Waste Management. 2009;3(1-2):91-106.

Heitholt JJ, Sloan JJ. Enhancement of vegetable crop growth with biosolids and yard-waste compost on a calcareous clay soil. Texas Journal of Agriculture and Natural Resources. 2016;19:80-92.