Trends and constraints in the utilization of African nightshade (Solanum nigrum complex) in Tanzania: A case study of Kilimanjaro and Morogoro regions

Abstract

African nightshade (ANS, Solanum nigrum complex) is among the most widely distributed and consumed indigenous vegetables in Tanzania. Several challenges hamper the utilization of ANS. This study sought to assess trends and constraints to ANS utilization in Kilimanjaro and Morogoro regions, Tanzania. Quantitative and qualitative methods were employed to collect information on ANS production, processing, and postharvest handling. Semi-structured questionnaires were used to collect quantitative data, whereas focus group discussion (FGDs) was used to collect qualitative data. A total of 627 farmers participated to fill questionnaire, and about eight FGDs with 6 - 10 participants conducted in Kilimanjaro and Morogoro. The results showed that 72.1% of farmers grow different ANS species, with Solanum scabrum vastly cultivated. Also, 79.4% of ANS farmers use irrigation, handheld hoe (97.6%), pesticides (70.7%), and fertilizer (64.8%) to produce ANS. African nightshade is mainly used as food (96.1%), animal feed (41.3%), and medicine (38%). On average, only 5% of ANS sales contributed to family income. Findings show that the main constraints to ANS utilization were pests and diseases (92.9%), lack of knowledge (58%), fertilizer shortages (51%), shortages of pesticides (50%), inadequate means of transport (50.4%), lack of extension services (48%), improper postharvest handling (41.4%) and inadequate storage facilities (34%). Postharvest losses accounted for 78.4% loss of ANS. Mitigation measures were; harvesting in small quantities (54.5%) and instant selling (61.9%) of fresh ANS. Drying (5.3%) and fermentation (1.1%) were the minimal value addition methods for ANS preservation. Moreover, boiling (63.0%) and frying (45.4%) were the typical methods of cooking ANS. More emphasis should be placed on good agricultural practices, providing knowledge to farmers, and supporting access to agricultural inputs such as pesticides, fertilizers, and quality seeds. Furthermore, knowledge of the processing and preservation of ANS is necessary for farmers to improve utilization, reduce losses, and ensure ANS availability. Also, research should focus on breeding local cultivar, which is resistant to pests and diseases. Key words: African nightshades, Solanum nigrum complex, cultivation, postharvest handling, utilization, processing, preservation