Assessment of Pepper Leaf Curl Virus Disease Incidence, Severity (PepYLCV) and Vector (Bemisia tabaci) Population Dynamics in Kebbi State, Nigeria

Abstract

Pepper (Capsicum spp.) is widely produced and consumed in Sub-Saharan Africa. Nigeria is the largest
producer of pepper in Africa. A field study was conducted in two Local Government Areas of Kebbi State,
Nigeria. A field assessment was carried out in Jega (Birnin Malan and Gindi) and Aliero (Kashin Zama
and Marmaro) to assess the incidence and symptom severity (SS) of pepper leaf curl virus (PLCV) and
the population density of its whitefly vector on pepper plants. Thirty symptomatic and asymptomatic
pepper plants were randomly selected per location and evaluated for visual disease symptoms and severity.
Whiteflies were counted on the terminal leaflets of each assessed plant. Results revealed notable PLCV
incidence, SS, and high whitefly populations across both locations. Among the surveyed areas, Kashin
Zama recorded the highest disease incidence (60.0%), followed by Aliero and Birnin Malan (53.33%),
Marmaro and Gindi (50.0%), and Jega (40.0%). The highest SS was observed in Aliero (2.2%), followed
by Kashin Zama (2.0%), Marmaro (1.9%), and Birnin Malan and Gindi (1.8%), with Jega recording the
lowest severity (1.5%). Whitefly populations were highest in Kashin Zama (23.0 per plant), followed by
Aliero (21.0), Birnin Malan (20.0), Marmaro (19.0), Jega (18.0), and Gindi (17.0). These findings confirm
the presence and variability of PLCV and its vector in Kebbi State, highlighting the need for region-specific
management strategies, as this will mitigate vector population and disease pressure in the study area.