Tillage practices on smallholder farmers’ maize productivity in Zambia

Abstract

The adoption of various tillage methods has varied across the continent. This study focusses on determining the factors that influence adoption of various tillage practices and the impact of tillage methods on maize productivity in Zambia. In Zambia, prior studies have focused on making comparisons of tillage methods within the CT methods and not conventional tillage types. The previous studies on conventional tillage types have lumped all the conventional tillage types and hence the need to rigorously estimate the impact of tillage practices on maize productivity without lumping conventional tillage methods. Therefore, the conventional tillage methods that were included in this study include hand-hoeing, ploughing and ridging tillage methods. The study uses 2012 Rural Agriculture Livelihood Survey (RALS) data collected by Indaba Agricultural Policy Research Institute (IAPRI) in collaboration with Central Statistical Office (CSO) and the Ministry of Agriculture (MOA). This data has 442 standard enumeration areas (SEAs) and administered to 8,840 smallholder farm households. The probit model was used to examine factors influencing adoption of various tillage practices. Estimation of the propensity scores and generation of balancing property was satisfied using PScore. To measure the impact of tillage methods on maize productivity, this study employed the mixed effect regression model (MRM). The MRM was necessary to account for households with multiple maize fields. The results indicated that ploughing tillage method was the common tillage method practiced by smallholder farm households at 41.6 percent and CT was found to be the least tillage method practiced by smallholder farmer households. Results from the probit model indicate that there are various factors that influence the adoption of various tillage methods. Age and education level of household head has a strong influence on the adoption of hand-hoe. Similarly, education was found to influence the adoption of CT. The MRM indicate that smallholder farm households who practice CT would experience higher maize productivity of 8.3 percent. Ploughing tillage methods though not statistically significant was found to increase the productivity of maize by 1.9 percent while hand-hoe was found to reduce the productivity of maize by 0.2 percent. In conclusion, smallholder farmer households with lower levels of education tend to practice more of conventional hand-hoe tillage method. On the other hand, more educated smallholder farmers adopt more of CT. Smallholder farmers in their young stage in life would adopt less of ploughing tillage method but as age progresses they began to adopt more of ploughing tillage method. Finally, the results indicate that smallholder farmer households that adopted CT realized more maize produced per hectare than they would if they had adopted any other tillage method. Therefore, this study recommends that the promoters of CT in Zambia should continue doing so as maize produced per hectare from CT tend to be more than any other tillage method. Key words: Conventional tillage method, conservation tillage method, maize productivity, adoption.