Ovipositional and pollination behaviour.pptx

These phases include the choice of habitat, the approaching of a plant from a distance, the decision to land on the potential host or not, the decision to oviposit or not and, when applicable, the size of the egg batch.

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2. OVIPOSITIONAL BEHAVIOUR AND POLLINATION BEHAVIOUR OF INSECTS Presented by Pogula Kranthi Ph.D Ist Semester Dept. Of Entomology College of Agriculture Raipur

3. OVIPOSITIONAL BEHAVIOUR IN INSECTS

4. These phases include the choice of habitat, the approaching of a plant from a distance, the decision to land on the potential host or not, the decision to oviposit or not and, when applicable, the size of the egg batch. It is fundamentally different behavioural processes, the first involves searching for a potential host, the other involves assessment of host quality leading to acceptance or rejection of the host. The choice of the ovipositing site by the female is very important for the survival of a species because most insect larvae have a very limited capability to locate alternative host plants. Ovipositional behavior

5. Examples- Females of outbreak species tend to lay their eggs in batches as opposed to scattering their eggs throughout a stand of the host plant. In some extreme cases, the females are flightless and deposit all their eggs in a single mass. Non-outbreak species tend to lay their eggs singly.

6. Manner and place of oviposition in insects 1. Dolichomitus imperator Ichneumon parasitoid wasps, Family- Ichneumonidae , Order- Hymenoptera The process of oviposition in Dolichomitus imperator : 1 Tapping with her antennae the wasp listens for the vibrations that indicate a host is present; 2 With the longer ovipositor, the wasp drills a hole through the bark; 3 The wasp inserts the ovipositor into the cavity which contains the host larva; 4 Making corrections; 5 and 6 Depositing eggs. Cont….

7. (1) P. laciniata adults could look for optimal temperature ranges for the development of the eggs carried on their backs, given that their host plant, Paronychia argentea ( Cariofilaceae ), grows in very hot and dry places ( Lazaro , 1920); (2) carrying the eggs on their body could minimize egg predation rates by other insects (such as ants) (3) egg carrying could be an effective protection agianst an egg parasitoid wasp (Hymenoptera: Scelionidae ). 2. The golden egg bug ( Phyllomorpha laciniata ) , is a unique species in which females exhibit a flexible pattern of oviposition behavior .. Egg carrying may enhance egg survival in three different ways:

8. B. tryroni  lay their eggs in fruit. Females prefer to lay their eggs in fruit that is sweet, juicy, and not acidic.  The presence of other female flies in pre- or post- oviposition on a piece of fruit was found to have no bearing on another female's likeliness to land on the fruit. However, female flies were more likely to bore into a piece of fruit that other female flies were currently ovipositing into, therefore increasing the density of larvae within a single piece of fruit. 3 . Queensland fruit fly ( Bactrocera tryoni ) is a species of  tephritid fruit fly  

9. Oviposition behaviour resistance to oviposition may come from plant characteristics that either fall to provide appropriate oviposition -inducing stimuli or provide ovipositional inhibiting stimuli. Oviposition preference is discussed on two bases of the plant’s- 1. Biophysical traits – Plant pubescence Frego bract Visual factors 2. Biochemical traits  OVIPOSITIONAL BEHVIOUR IN RELATION TO HOST PLANT FACTORS 

10. Plant pubescence- Example: Soybean varieties with a dense hairiness of foliage can manifest both antixenosis to oviposition and feeding deterrence against leafhoppers, The simple trichomes deter oviposition and feeding by preventing; the insect’s ovipositor or proboscis from reaching the plant epidermis(Lee 1983). Frego Bract- Other morphological features of plants, such as frego bract in cotton, help reduce the number of eggs laid and subsequent damage by boll weevils Anthonomus grandis (Jenkins and Parrot 1971).

11. c . Visual Factors - The colour and shape of plants remotely affect host selection behaviour of phytophagous insects and have been associated with some resistance. Example- Specific colour-related resistance, For example, the red and glossy nature of Cruciferae plants was a major factor conferring antixenosis resistance against the cabbage aphid Brevicoryne brassicae (Singh and Bills 1993). Yellow colour is preferred by aphids. Green and blue green is preferred by cabbage butterfly. Dark green preferred by rice leaf folder. 

12. Chemical cues are involved in all the three phases of host selection behavior ; orientation, oviposition and feeding. Many factors play a role in the process of opposition by different insects, but long-range orientation of many insects to their host plants is known to be guided by volatile, compounds emanating from plants. Volatile hydrocarbons and other secondary compounds act as oviposition deterrents. Onion volatile diallyl disulfide is antagonistic to onion fly Delia antiqua . 2. Biochemical Factors

13. Pollination Behavior in insects

14. Pollination behavior in insects The most common plant pollinators, insects that deliver pollen from plant to plant, are bees and butterflies. The transfer of plant pollen to a female species of the plant enables fertilization and the growth of new plants. Pollinators are essential for continued plant growth in the wild. Insect that feed on pollen and nectar are specialized behavior that have a mutualisties , rather than parasitic, relationship to their host plant .

15. Butterflies and moths Also guided by sight and smell. Butterflies can see red and orange flowers. Usually shaped as a long tube because of insect’s proboscis – to get nectar. Moth- pollinated flowers are usually white or pale, with sweet, strong odor - for night pollination . Hummingbird moth hovering and darting from flower to flower.

16. Flies and beetles Flies like flowers that smell like dung or rotten meat. Lay their eggs there, but larvae die due to lack of food. Ex. , Hoverflies tachinid flies, bee flies, small-headed flies, March flies, blowflies etc. Beetles pollinate flowers that are dull in color, but have very strong odor. Spicy, fermented scents or decaying scents that attract beetles. Ex. Soldier beetles, jewel beetles, blister beetles, long-horned beetles, tumbling flower beetles, scarab beetles, sap beetles, false blister beetles, and rove beetles etc.

17. Bees Bees – are the most important group of flower pollinators and they live on the nectar and feed larvae, also eat the pollen. Bees are guided by sight and smell See yellow and blue colors, also ultraviolet light (not red) Flowers have “honey guides” and bee landing platforms..

18. Wasp Orchid plant releases a chemical cocktail that smells like a caterpillar infestation to lure the predatory wasps to their flowers. Ex. Common wasps ( Vespula   vulgaris ) and European wasps ( Vespula   germanica ). The most notable wasp pollinators are the fig wasps, which pollinate the tiny flowers inside the developing fig fruit. Without fig wasps, there would be a very low likelihood of figs in the wild.