• R Velayudhan

      Articles written in Proceedings – Animal Sciences

    • Pollination potential of thrips (Insecta: Thysanoptera) in some Solanaceous plants

      R Velayudhan R S Annadurai

      More Details Abstract Fulltext PDF

      Pollination by two species of flower thrips in six Solanaceous plants (four perennials and two seasonal) were studied. The results highlight the role of thrips in both self and cross pollination of these flowers. The findings also suggest that in view of the stigmatic surface in all the flowers being at a higher level than the anthers, there is more entomophily. Data relating to the population dynamics of thrips as well as the pollen load of thrips are also included.

    • Pollination potential of thrips (Insecta: Thysanoptera) in some fabaceous plants

      R S Annadurai R Velayudhan

      More Details Abstract Fulltext PDF

      The vector role of thrips in pollinating several fabaceous flowers has been studied. The flowring phenology showed a coincidence with the life cycle of the thrips species. The population dynamics of the thrips, crop-weed dispersal, the pollen carrying efficiency and the percentage of pod set are discussed.

    • Host preferences in some pentatomids and related impact on the fecundity of their parasitoids

      R Velayudhan

      More Details Abstract Fulltext PDF

      Two species of polyphagous parasitoids,Gryon sp andTelenomus lucellus, parasitising the pentatomidsAcrosternum graminea andAgonoscelis nubila were subjected to host preference studies and consequent impact on the rates of parasitism of these host eggs. Chemical composition of these eggs were correlated with the age specific fecundity of the parasitoids. Polyphagous pentatomids likeAcrosternum graminae had varying fecundity on different host plants likeCleome viscosa, Gynandropsis pentaphylla, Leucas aspera, Croton sparciflorus, Acalypha indica etc and this variation was found to depend on the chemical parameters of these host plants. The overall egg output of the pentatomids was also found to influence the percentage of parasitism.

    • Reproductive strategies of an egg parasitoid,Trissolcus sp. (Hymenoptera: Scelionidae) on two different hosts

      R Senrayan R Velayudhan S Rajadurai

      More Details Abstract Fulltext PDF

      Reproductive strategies in relation to host diversity of a scelionid egg parasitoid,Trissolcus sp. onEupaleopada concinna Fab. andHomoeocerus prominulus (Tagus) are discussed, followed by the life table analysis of the parasitoid, indicating the preponderance of females due to solitary parasitism on the former host and a balanced sex ratio due to superparasitism on the latter.

    • Insect growth regulator XRD-473 (OMS 3031), a prospective compound for control of mosquito vectors

      Dominic Amalraj R Velayudhan

      More Details Abstract Fulltext PDF

      Insect growth regulating activity of a substituted urea compound XRD-473 (OMS 3031) was evaluated against the target species viz.Culex quinquefasciatus, Aedes aegypti, Anopheles stephensi and non target speciesToxorhynchites splendens. This compound inhibited the emergence of all these mosquito species with EI50 values of 9×10−5, 1·09×10−4, 2·22×10−4 and 2·14×10−4 mg (ai)/l respectively. Emergence inhibiting activity of XRD-473 was found to be more than fenoxycarb, and S 21149 against one or other species. In stagnant polluted water, the activity of the compound againstCulex quinquefasciatus was for shorter duration of 5 and 10 days at 0·02 and 0·2 kg(ai)/ha respectively whereas in clear water the activity was for longer duration i.e. 11 and 17 days at the same dosage. However, in drain the activity was negligible i.e. 12 days at 2 kg(ai)/ha. More than two weeks control ofAedes aegypti was obtained in cement tank at the treatment rate of 0·2 kg(ai)/ha whereas at the lower dose of 0·02 kg(ai)/ha this compound was effective for less than a week.

  •  

© 2021-2022 Indian Academy of Sciences, Bengaluru.