Assessing the effect of crop intensification in improving aricultural productivity in smallholder farmers' fields : a case study of northern KwaZulu-Natal, South Africa.

Abstract

Crop intensification is adopted by different countries to address their challenges, which may include low standards of food and nutrition security, limited arable land and land degradation. To assess the effect of crop intensification in improving agricultural productivity in smallholder farmers in Northern KwaZulu-Natal, a qualitative study and in-field experiment were conducted. In a qualitative study the Participatory Rural Appraisal (PRA) tools namely, focus group discussions, transect walks and key informant interviews was used. A random purposive sample of 249 smallholder farmers from 5 local municipalities of uMkhanyakude district was undertaken. The following information was explored: different farming systems; landscape; availability of irrigation systems or water sources; classification of farming soil types; perception of soil fertility; planting and rainfall patterns. Smallholder farmers’ demographics, socio-economic status, typical farming systems, differences between backyard gardens and crop fields, water sources, knowledge and skills on farming systems and practices, understanding and benefits of mixed farming, crop mixing and intercropping, soil fertility and soil acidity management were also explored. The findings of the study revealed that the age of the smallholder farmers ranged between 40-65 years. About 90% of the smallholder farmers who participated in this study were females. 45% of smallholder farmers’ households are headed by females. A typical household of the smallholder farmers, is characterised by more than two dwelling places in one household compound with mixed farming. Water is a serious problem in uMkhanyakude district. 70% of the farmers primarily used indigenous knowledge and acquired their skills on farming systems and practises from generation to generation indigenous knowledge system. In-field experiment was conducted. It was laid out in a randomized complete block design (RCBD) with three replicates having a net plot size of 3.6m x 5m. The following treatments were evaluated: Maize intercropped with beans (T1), Maize intercropped with pumpkins (T2), Maize intercropped with beans and pumpkins (T3), Maize sole crop control (T4), Beans sole crop control (T5), Pumpkins sole crop control (T6) and Bean intercropped with pumpkins (T7). Productivity was measured using the following indices: Land Equivalent Ratio (LER), Area Time Equivalent Ratio (ATER), Competition Ratio (CR), Relative Crowding Coefficient (K) and Aggressivity (A), Actual Yield Lost (AYL), Intercropping Advantage (IA) and Monetary Advantage Index (MAI). The study revealed that the intercropping system with three crop species in all three location showed greater values of LER (1.8, 1.9, and 1.7) and ATER (1.8, 1.9, 1.7). The crowding coefficient (K) was the highest in Mtubatuba and Hluhluwe treatment 3 (maize/bean/pumpkin) (80.72 and 61.78) respectively. Intercrops showed positive Agressivity, and greater competition ratio and actual yield loss when compared with the main crops. Intercropping advantage (IA) and monetary advantage (MAI) in treatment 3 (maize/bean/pumpkin in all locations showed greater values (58327, 12850, 5532) and (54573, 59487, 19606) respectively. The productivity of the intercropping system where there are more than two crops is considered greater in terms of land equivalent ratio (LER), area time equivalent ratio, (ATER).