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A wide range of quinoa pests are known throughout the world. The most serious of the Andean pests are Eurysacca melanocampta (Meyrick) and E. quinoae Povolný (Lepidoptera: Gelechiidae), found mainly in Peru and Bolivia, which cause considerable yield losses. Insects found elsewhere in the world are polyphagous pests constituting a wide range of potential pests if quinoa is implemented as a crop in those regions. Other major pests include a group of cutworms (Noctuidae). Apart from insects birds cause a major loss through foraging, damaging cotyledonous plants and inflorescences, with yield losses of up to 60%.Cultural practices and host plant resistances will be important components of integrated pest management (IPM). Biological control of the main pests is good; for example, up to 45% of Eurysacca melanocampta in the field are usually controlled by a range of parasitoid species as well as predators in the field.Future research should focus on the main pests in order to reveal basic information on interactions with the host plant. Population carryover from one growth season to another and the role of environmental factors on insect development and population size should also be studied.

1 The effects of reduced insecticide and herbicide dosages on total dry mass of carabids and their generic components were examined using fenced pitfall traps in winter wheat fields on three farms in Southern Zealand, Denmark. 2 The estimated total dry mass of carabids increased by 25% when the pesticides were reduced to one fourth of the normal application rates. 3 At reduced dosages, the activity of the genus Pterostichus was increased by 62%. The activities of Loricera and Demetrias were increased by 67% and 56%, respectively, although significant interaction terms indicated that the dosage effect was not uniform for these genera on all farms. Calathus tended to be more numerous with reduced pesticide applications. By contrast, catches of Bembidion, Synuchus and Trechus decreased by up to 45% at reduced dosages. 4 A higher weed cover due to reduced herbicide applications probably benefited most species, except those having habitat associations with sparse vegetation such as the field-inhabiting Bembidion and Synuchus. 5 The higher activity of larger carabids may lead to enhanced predation on smaller carabids and hence different carabid assemblages.

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The cabbage stem flea beetle, Psylliodes chrysocephala (L.) (Coleoptera: Chrysomelidae), is a major pest of winter oilseed rape. Despite the importance of this pest, detailed information on reproduction to predict risk of crop damage is lacking. This study investigates the effect of temperature on parameters of reproduction, egg development and viability at five constant temperatures. Significant temperature effects were found on the pre-oviposition period, total number of eggs laid, daily oviposition rate, female longevity, egg-development rate and viability. The mean length of the pre-oviposition period ranged from 93.1 days at 4°C to 14.6 days at 20°C. Analysis of total number of eggs laid and daily oviposition rate during female lifespan estimated the highest total number of eggs laid (696 eggs/female) at 16°C and the highest oviposition rate (6.8 eggs/ female and day) at 20°C. The daily oviposition rate at 20°C was not significantly higher than 5.4 eggs/female and day at 16°C. Female longevity was significantly longer at 4°C, shorter at 20°C and not significantly different between 8, 12 and 16°C. Estimated 50% survival time of females was 239, 153, 195, 186 and 78 days at 4, 8, 12, 16 and 20°C, respectively. A linear model of egg development at 8-20°C estimated the lower developmental threshold to be 5.1°C and the thermal constant for development 184.9 degree-days. The percentage of eggs hatching was significantly lower at 4°C than at all other temperatures tested. The estimated mean hatching percentages were 47. 3%, 70.0%, 72.4%, 66.2% and 67.9% at 4, 8, 12, 16 and 20°C, respectively. These results can be used to predict the start and intensity of egg-laying in the autumn and the appearance of larvae in the field from knowledge about time of field invasion and from monitoring the weather.