Seasonal abundance of Maiestas banda (Hemiptera: Cicadellidae), a vector of phytoplasma, and other leafhoppers and planthoppers (Hemiptera: Delphacidae) associated with Napier grass (Pennisetum purpureum) in Kenya

Abstract

Napier grass (Pennisetum purpureum Schumach), the main fodder crop in eastern Africa, has recently been severely affected by Napier stunt disease, which is caused by phytoplasma. We have recently confirmed that a leafhopper, Maiestas banda (Kramer) transmits phytoplasma in Napier grass in Kenya. Several other species of leafhoppers (Cicadellidae) and planthoppers (Delphacidae) are also associated with Napier grass, and some could be potential vector(s) of phytoplasma, but little is known about phenology and movement activity of these insect groups. We monitored the populations of M. banda and other leafhoppers and planthoppers in Napier grass fields at two sites in western Kenya for 18 months. High population densities were observed for M. banda, suggesting that it plays a major role in the disease epidemics in the region. Sampling with Malaise traps and a vacuum-suction sampler revealed that M. banda and five other species (Cicadulina mbila (Naudé), Cofana polaris Young, Cofana unimaculata (Signoret), Leptodelphax dymas Fennah, Maiestas sp.) exhibited a high proportion of males in the trap catches, implying higher mobility in males than females. A suction sampler collected more individuals of three species (M. banda, Maiestas sp., and Thriambus strenuus Van Stalle) from phytoplasmainfected than healthy plants at both sites. The populations of M. banda and other five species (C. unimaculata, Maiestas sp., L. dymas, T. strenuus, and Rhinotettix sp. 1) showed a conspicuous peak at the end of the short rainy season (Sep to Dec), implying that common regulatory factors such as rainfall may affect the leafhopper and planthopper complex.

Sex-Dispersal Differences of Four Phloem-Feeding Vectors and Their Relationship to Wild-Plant Abundance in Vineyard Agroecosystems

“…Considering their high population densities, N. fenestratus and P. alienus might have important roles in the plant disease epidemiology cycle in these two agroecosystems. Similarly, high population densities of other leafhopper species, like Maiestas banda (Kramer; Cicadellidae) in Kenya (Koji et al 2012) and Draeculacephala minerva Ball (Cicadellidae) in California (CabreraÐLa Rosa et al 2008), were shown to be involved in the transmission of Napier stunt disease and the bacterium Xylella fastidiosa, respectively.…”

The Significance of Napier Grass Stunt Phytoplasma and Its Transmission to Cereals and Sugarcane

“…Later, Koji et al. () while using malaise traps showed that these insects were the most abundant species found on Napier grass in western Kenya where NGS disease was first reported (Orodho ), supporting its role in the disease epidemics in the region.…”

Napier grass stunt disease prevalence, incidence, severity and genetic variability of the associated phytoplasma in Uganda

“…Although the reasons for less disease risk in western Uganda is not known, we presuppose that it is due to limited movement of Napier grass planting materials among farmers since a vast number of them practice extensive farming. Although the vector species responsible for transmission of Napier grass stunt phytoplasma in Uganda are not yet known, Recilia banda (Aauchenorryncha: Cicadellidae) has been reported by Obura et al (2009) to transmit NGSD andKoji et al (2012) found it in high abundance in western Kenya. Therefore, there is a high likelihood that the vector exists in Uganda too, playing a major role in the spread of the disease within and between fields.…”

“…The primary means of NGSD spread is through introduction of infested planting materials (cuttings or clump splits) by farmers and/or infected vector carrying the phytoplasma (Orodho, 2006;Koji et al, 2012). Although the vector transmitting NGSD in Uganda is not known, Obura et al (2009) reported Recilia banda Kramer to be the vector of Napier stunt phytoplasma in Kenya.…”

“…Although the vector transmitting NGSD in Uganda is not known, Obura et al (2009) reported Recilia banda Kramer to be the vector of Napier stunt phytoplasma in Kenya. Indeed Koji et al (2012) found this vector abundant in Napier grass fields in western Kenya. Given the close proximity of the two countries, it is likely that the vector is also abundant in Uganda, transmitting the disease.…”