The development of Dysdercus voelkeri on three new sorghum varieties and assessment of its damage to grains

Abstract

The development of Dysdercus voelkeri on three dwarf and short-season varieties of sorghum: BES, HP3 and HP8 and its damage to the grains were studied in the laboratory and greenhouse, respectively. An average development period of 27 days was recorded on the three varieties. The fecundity, fertility, live-weight and dorsal surface area were significantly higher in insects that developed on HP8 than in those that developed on BES and HP3. There were, however, no significant differences in these parameters except fertility between the insects that developed on BES and HP3. The highest grain damage of 56.6% was recorded for HP8, while 51 and 27.6% grain damage were recorded for BES and HP3, respectively. The potential pest status of D. voelkeri on these new and improved sorghum varieties in the southern Guinea and derived savanna zones of Nigeria is confirmed in these studies. Effective control of this bug and other sucking insects at the milky stage of grains' development is suggested for high yield and good quality grains.