Effect of Temperature on Population Dynamics of Meloidogyne Spp. and Fusarium Spp. Infesting Sweet Pepper in Niger

Abstract

Meloidogyne spp. and Fusarium spp. cause wilt disease in sweet pepper and result in decline of its production. Other limiting factors of sweet pepper production are inappropriate agronomic practices and lack of effective climate adaptation strategies. The aim of this study was to investigate on one hand, how farmers perceive climate change and their access to agricultural extension services and, on the other hand the distribution and identification of causal agents of wilt disease and also to find out the effect of temperature on the co-infection of pathogens on sweet pepper. The results revealed that the perception of farmers on rainfall patterns do not match with past meteorological records. Respondents indicated that there is an increase in temperature which is in agreement with climatic data evidence. Crop diversification was found as the major adaptation strategy to climate variability. The lack of sufficient access to information is the constraints that hindered farmers to adapt effectively. The incidence of the Meloidogyne spp. was 100% in both districts while the occurrence of Fusarium spp. was 80.32% and 62.23% in Diffa and Aguie respectively. Based on morphological and molecular characterization, three pathogens were identified in sweet pepper; Meloidogyne enterolobii, Meloidogyne incognita and Fusarium solani. The sequential and concomitant inoculation of the fungus and/ or the nematode did not cause the sudden death of sweet pepper plants as observed in the field. It only resulted in significant increase in yellowing in leaves and high nematode and fungal reproduction in inoculated plants in comparison to the uninoculated plants. Temperature greatly influenced the reproduction capacity of M. enterolobii and F. solani.