Weather variability and its effects on agricultural and food systems are burgeoning global concerns. This study examined the effects of weather variability in the derived savannah and rainforest agroecologies, on crop yields in Southwest Nigeria, and what it portends for food and nutrition security in the region. The trends in the distribution of rainfall and temperature were analysed using the Sens method. The effects of weather variability on crop yield and inferences on what it portends for food security were determined using a stepwise regression model. The results revealed that rainfall fluctuations decreased the yields of cassava (Manihot esculenta) and yam (Dioscorea spp.) in the derived savannah; while a decrease in temperature may support improved yields for maize (Zea mays), sorghum (Sorghum bicolor) and cowpea (Vigna unguiculata). The increase in yields of cocoa (Theobroma cacao) and cocoyam (Colocasia esculenta) would be hampered by increasing maximum temperatures in the rainforest agroecology. Increasing rainfall and temperature would impact warmer conditions that support rapid crop putrefaction, flooding, droughts, challenging postharvest crop management, pest and disease proliferation, and ultimately, reduced crop yields. On the other hand, perpetually low rainfall and temperature conditions will cause poor seedling emergence and growth, seed and total crop loss. It is, therefore, imperative that effective climate adaptation and mitigation mechanisms be put in place across the agroecologies in the region.

This paper examined the research-extension-farmer-input dealer and marketer linkage activities in the North West Province of South Africa. A simple random sampling technique was used to select researchers, extension agents, farmers, agricultural input dealers and marketers. Their responses in linkage activities were elicited through a structured questionnaire. The F value for linkage = 41.817(p< 0.05) shows that there is a significant difference among stakeholders with extension agents having the highest mean of 51.63. In contrast, the marketers have the lowest mean of 37.16. This indicates that extension agents were involved in more linkage activities than other stakeholders in the agricultural innovation systems covered in this study.

The current study examined the extent of knowledge concerning agricultural innovation systems amongst researchers, extension agents, farmers, input dealers, and marketers, while determining their attitude towards collaborating with agricultural innovation systems. Through using a simple random sampling technique; researchers, extension agents, farmers, input dealers, and marketers were selected as the study population. Information was gathered by distributing a structured questionnaire amongst the various participants and analysing the data gained concerning their wealth of knowledge and their corresponding willingness to collaborate. The results show that researchers, extension agents, farmers, input dealers, and marketers are aware of, and have adequate knowledge of, these systems available to them, to be able to utilise them effectively. However, they expressed different attitudes towards collaboration with agricultural innovation systems.