On the Biology, Bionomics, seasonal Incidence and Control of Piezodorus rubrofasciatus Fabr., a Pest of Linseed and Lucerne at Delhi.
The Pentatomid, Piezodorus hybneri (Gmel.) (rubrofasciatus (F.)), all stages of which are briefly described, is a pest of lucerne, flax, soyabeans, and potato at Delhi, being particularly numerous on lucerne. In field-cage tests, the egg stage lasted six days at average minimum and maximum temperatures of 74 and 88°F. and 50 per cent. relative humidity, and 3-4 days at higher temperatures, the five nymphal instars 5-7, 5, 3, 5-6 and 5 days, respectively, and the complete life-cycle 24-32 days. The pre-oviposition period lasted 10-12 days, pairing occurring about four days after adult emergence, and the eggs were laid in masses of 24-30, usually on the upper surface of the leaves. The insect is most numerous in March-April, when it causes much harm to the crops attacked, and then declines in numbers. Sweeping with a net gives effective control.