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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.

The trichome‐bearing wild potatoes Solanum berthaultii (Hawkes) and Solanum tarijense (Hawkes) (Solanaceae) have noted resistance to leaf‐feeding insect herbivores; however, little is known about their resistance to tuber‐feeding herbivores. This study evaluates resistance in tubers of these two species to attack by the potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae). Tubers from a range of accessions were presented to recently emerged neonate tuber moth larvae. Resistance to neonates varied between accessions and was generally higher in accessions of S. tarijense. The contribution to observed resistance of periderm vs. cortex factors was assessed by perforating tuber periderm in paired‐tuber experiments. Across species and accessions, an average of 62% of resistance was attributed to periderm‐related factors. All larvae entered tubers through the eyes. Unidentified cortex‐related factors affected larval development time and pupal weight. Sprouting compromised resistance by reducing the protective value of the periderm. The degree of sprouting also decreased larval development times and increased pupal weights in one of two accessions examined. These results demonstrate the potential of S. berthaultii and S. tarijense as sources of tuber‐resistance and identify accessions of both species with notably high periderm‐based protection. Levels of periderm resistance were not correlated to levels of cortex resistance and represent an independent resistance source compatible with the food value of crop potato.

Granulovirus (PoGV) is a promising candidate to substitute for chemical insecticides in integrated pest management (IPM) of the potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae). A procedure to assess pathogenicity (LC50) and its standardization is crucial for research into the use of pathogens as biocontrol agents. In the present study, an egg‐dip bioassay method was developed and its precision tested in a series of six bioassays over a time period of 18 months. Bioassays were carried out at 25 °C incubation temperature. The probit model as a statistical analysis method for the interpretation of concentration responses proved better than the exponential model. LC50 values ranged from 2.3 × 106 to 107 granules ml−1 with a mean of 5 × 106 granules ml−1 and regression slopes varied between 0.73 and 1.05 with a mean of 0.84. LC50 values and slopes displayed no significant differences according to their 95% confidence limits. The rate of harvested infected larvae showed a linear increase with increasing concentration on a log‐log scale. The mean natural mortality was 15% (SE ± 1.8%) and can be considered as a main factor producing variability among bioassays. The advantages of this bioassay method and its application in PoGV research are discussed.

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