Assessment of Yield of Tomato (Lycopersicon esculentum Mill.) and Soil CO2 Emissions as Influenced by Compost Doses and Irrigation Regimes
Abstract
Tomato (Lycopersicon esculentum Mill.) is one of the most important vegetables cultivated in Togo. Water stress constitutes one of limiting factors of production in dry season. Compost use improves soil properties and crop production but may lead to soil CO emission into atmosphere. This study assessed the influence of compost doses and irrigation regimes on 2 tomato yield and soil CO emission. Trial agronomics were conducted in dry season in year 2018 and 2019 in a randomized 2 complete block design with three repetitions. Treatments included control plots, compost plots and chemical fertilizer plots. Water was supplied according to three irrigation regimes of 1, 2 and 4 days interval. Tomato fruits were harvested when color was yellowish red. Soil CO emission measurement was conducted in four months (120 days) during field experiment 2 from January to April in 2019. Soil samples were collected from plots and incubated in laboratory. Soil CO emission was 2 measured everyday during 28 day’sincubation using 0.1 N HCl after precipitating the carbonate with a BaCl2 solution by alkali back-titrating. The results shown that highest tomato yield and highest soil CO emission were recorded on plots 2 treated with compost and submitted to two days interval irrigation while the lowest values of these parameters were obtained from control plots and treated plots submitted to daily and four days interval irrigation.This was noted that CO emission 2 from soil samples collected in third and fourth months of field experiment were more than those of first and second months.
Keywords
Download Options
Introduction
In West Africa, cultural methods in many cases still remain ancestral characterized by the use of rudimentary tools and low use inputs (improved seeds, mineral and organic fertilizers etc.), thus contributing to the continuous soil degradation. Farmers traditionally relied on long fallow periods to restore land fertility. However, population increasing has shortened the fallow periods and decreased the available agricultural land. Furthermore, farmers remove crop residues from the field and use them for feeding their livestock or as fuel to cook their food. Crops are grown continuously on poor soils. Especially with continuous cultivation, physical properties and productivity of many soils commonly decline due to decrease inorganic matter content (Lal, 1986). The red soil called “Terre de Barre” in coastal region of Togo does not escape this reality. These soils are overused and do not have the necessary time to replenish their organic matter stock. Demographic pressure and excess land use have led to a total depletion of these soils, resulting in a decrease in the stock of organic carbon and a destructuring of the surface horizons, reducing mainly food crop production (maize, cassava, cow pea, tomato etc.). Researchers have shown that application of waste composts at reasonable rates improves soil physical properties, increases available soil nutrient levels and plant growth (Hossain et al. 2017; Coulibaly et al. 2019). According to Edwards and Araya (2009), compost increases soil fertility by holding and gradually releasing nutrients and building up organic matter levels in the soil, improves also the water holding capacity of the soil and makes crops better able to survive droughts. On another side, the vegetable fields are small sizes about 0.25 – 0.50 ha in Togo where tomato (Lycopersicon esculentum Mill.) is one of the most important vegetables and cultivated in almost all parts of the country. Water stress constitutes one of the most important factor limiting plant growth and yield in dry season when the incidence of pests and diseases is minimal. Field water management practices is the most influential factors affecting crop yield particularly in irrigated agriculture (Al-Omran et al., 2005). Irrigation regime improves water use efficiency and has significant effect on the growth and yield of crops (Gudugi et al. 2012).Compost use in cropping systems may lead to soil CO emission into atmosphere although the 2 processes involved are not fully understood. Barton et al. (2016) reported that incorporating organic matter alters soil greenhouse gas emissions and increases grain yield in a semi-arid climate. Compost is known for its efficacy on agricultural productivity increase, but little is known about its effectiveness on tomato productivity in Southern Togo.The objective of this study was to assess the influence of household waste compost doses and irrigation regimes on the yield of tomato and the soil CO emissions in coastal region of Togo. 2
Conclusion
The influence of compost doses and irrigation regimes on tomato yield and soil CO emissions was assessed. Tomato yield 2 and soil CO emission values were proportional to compost doses applied. These results indicated that the application of 2 household solid urban waste compost increased soil microbial populations and consequently soil CO emissions. The highest 2 tomato yield and the highest soil CO emission values were recorded on the plots irrigated at two days interval regardless 2 fertilizer nature and compost doses. As our experiments were relatively short, to better assess the CO emissions from 2 compost applied to soil, long-term experiments are needed for a more reliable conclusion on the effect of applying household urban solid waste compost on soil carbon dynamics.