Assessment of yield loss due to the millet head miner, Heliocheilus albipunctella (Lepidoptera: Noctuidae) using a damage rating scale and regression analysis in Niger

Abstract

Abs tract. Linear equations for five pearl millet varieties were established for yield losses due to damage by the millet head miner, Heliocheilus albipunctella De Joannis (Lepidoptera: Noctuidae), using a panicle damage rating scale. A very high positive correlation (r> 0.90; P = 0.001) was found between damage rating and percent yield loss, and also between observed and predicted yield loss. The low percent absolute deviation (% ad) and deviation ratios (dr) between observed and predicted yield loss demonstrated the reliability of the damage rating scale, and the established yield loss equations. In addition, the damage rating on farmers' fields by farmers and a team of technicians showed that the method can be used for quick on-farm assessment of yield loss by extension agents and farmers. In four farmer's fields, the estimated yield loss for the local variety (Sadore local) ranged from 11.7 to 41.9%. Implications in the use of the method in future crop loss assessment in pearl millet are presented and discussed.

Biological control of the millet head miner Heliocheilus albipunctella in the Sahelian region by augmentative releases of the parasitoid wasp Habrobracon hebetor: effectiveness and farmers’ perceptions

“…But, according to Ooi (1996), generally, farmers do not pay attention to natural enemies of insect pests or are not able to distinguish between pest and beneficial arthropods. In addition, the majority of farmers recognized losses caused by MHM, similarly to earlier reports (Krall et al 1995;Youm and Owusu 1998). Before the implementation of this biocontrol program farmers were unaware of MHM natural enemies.…”

“…Its immature larval stages feed on the panicle and prevent grain formation (Ndoye 1991). Yield losses range from 40 to 85% (Gahukar et al 1986;Krall et al 1995;Youm and Owusu 1998).…”

Gestion de la chenille mineuse de l'épi du mil par des lâchers du parasitoïde Habrobracon hebetor Say au Niger

“…Ils sont proches des 40 à 85 % avancés par plusieurs auteurs, il y a quelques décennies (Gahukar et al, 1986 ;Youm et Owusu, 1998) ; cela montre que la MEM constitue encore une contrainte importante dans la zone agricole Sud du Niger.…”

On-farm biological control of the pearl millet head miner: realization of 35 years of unsteady progress in Mali, Burkina Faso and Niger

“…It seems appropriate to review the various individual and institutional actors involved from the mid-1970s until 2000, particularly in light of (i) the 10-40 per cent yield losses that must have been incurred during those 25 years (Youm and Owusu, 1998); and (ii) the fact that when the head miner outbreaks first occurred, it was already known that H. hebetor was cosmopolitan, and there were already mass rearing and release programmes to serve as models for the rapid development of a biological control system in the Sahel. Vercambre (1978), who was among the first to document increased incidence and severity of the head miner, was working with the French CIRAD (Agricultural Research for Development) in Senegal towards his Doctorat d'Ingénieur degree from the Université de Paris-Sud.…”

“…Such knowledge was lacking in the 1970s, when the head miner became a serious pest. In the 1980s, a number of ecological studies were undertaken in Senegal, Niger and Mali to better understand head miner biology, including its life cycle, reproductive behaviour and yield/infestation relations (Guèvremont, 1981(Guèvremont, , 1982(Guèvremont, , 1983Gahukar et al, 1986;Bhatnagar, 1989;Gahukar, 1990;Ndoye, 1991;Youm and Gilstrap, 1993;Krall et al, 1995;Youm and Owusu, 1998). Additionally, between 1981 and, natural indigenous enemies of head miners were collected in several Senegalese regions (Bhatnagar, 1989), and categorized by the growth stage during which they attacked.…”