Bionomics of Migratory Pest Insects
Bionomics of Bionomics of Migratory Pest Insects Migratory Pest Insects
1.Population Density and Food Quality (1)Generally,migratory trait of locusts is influenced by population density of locusts and availability of host plant.At the same time,availability of host plant is adjusted by population density.It is often found that migrating or scattering occurs during the insect larval or adult stage when the population density is higher,resulting in a lower population density that can avoid competition between individuals
(1) Generally, migratory trait of locusts is influenced by population density of locusts and availability of host plant. At the same time, availability of host plant is adjusted by population density. It is often found that migrating or scattering occurs during the insect larval or adult stage when the population density is higher, resulting in a lower population density that can avoid competition between individuals. 1. Population Density and Food Quality Population Density and Food Quality
1.Population Density and Food Quality (2)Not all species,however,have these traits. Some species do not migrate at all,even if population density and/or feeding needs would induce them to do so. (3)In spite of the fact that bad environment conditions can induce migration in migratory insects,there are,for unknown reasons,some insect individuals who migrate but do migrate to a further place even there is enough food near by
(2) Not all species, however, have these traits. Some species do not migrate at all, even if population density and/or feeding needs would induce them to do so. (3) In spite of the fact that bad environment conditions can induce migration in migratory insects, there are, for unknown reasons, some insect individuals who migrate but do migrate to a further place even there is enough food near by. 1. Population Density and Food Quality Population Density and Food Quality
2.Light Intensity and Photoperiod Different light conditions required for the initiation of flight. Photoperiod is one of the conditions that causes flight during spring and autumn
¾ Different light conditions required for the initiation of flight. ¾ Photoperiod is one of the conditions that causes flight during spring and autumn. 2. Light Intensity and Photoperiod Light Intensity and Photoperiod
3.Temperature Lowest temperature for initiation of flight Brown rice planthopper:l6℃； Cnaphalocrocis medinalis:13C Black cutworm:6℃ Oriental armyworm:8℃。 Impacts the flight height Influence on landing
Lowest temperature for initiation of flight Brown rice planthopper: 16 ℃ ; Cnaphalocrocis medinalis: 13 ℃ Black cutworm: 6 ℃ Oriental armyworm: 8℃。 Impacts the flight height Influence on landing 3. Temperature Temperature