MSc

Mango inflorescence hosts a varied complex of insect and non insect population. This has resulted in poor fruit set and yield of mango. In the study entitled “Incidence and management of insect pests infesting inflorescence of mango”; the documentation of various insect pests attacking mango inflorescence was conducted in the three different blocks of Thiruvananthapuram district viz., Nemom, Athiyannur and Parassala whereas the field experiment for the management of insect pests infesting mango inflorescence was done during the period 2018-2020 in an orchard located at Kollengode of Palakkad district.
The collected specimens included pests, floral visitors and natural enemies from the nine different orders including Araneae. Insect pests from 15 different families of five different orders were identified with the assistance of expert taxonomists.
Hoppers posed a serious threat to the mango ecosystem in its vegetative and reproductive phase. The commonly noticed species during the field visits in Palakkad was Idioscopus sp. Mealy bugs and scales were the other common hemipterans recorded during the documentation studies. They were mainly from the families of Pseudococcidae and Monophlebidae consisting of Crisicoccus hirsutus, Rastrococcus iceryoides, Ferrisia virgata Formicococcus mangiferacola, Icerya sp. and Rastrococcus sp. Cowbugs were also noticed from the panicle and some in association with ants like; Camponotus compressus. The thrips were from the families of Phlaeothripidae ie., Gynaikothrips sp. and Haplothrips sp. Chrysomelids from the tribe Alticini included Nonartha sp. and Monolepta sp were found feeding on mango inflorescence. The weaver ant Oecophylla smaragdina made nests on mango inflorescence by mild to severe webbings on the panicle.
The commonly recorded lepidopterans from the mango panicle were included in the family, Geometridae, Noctuidae, Lycaenidae, Torticidae, Nolidae and Erebidae. Around 17 species were identified; comprising of Comostola laesaria, Chlumetia transversa, Anthene lycaenina lycaenina, Rapala manea , Archips micaceana, Nanaguna breviuscula, Gatesclarkeana erotias, Bombotelia jocosatrix, Perixera
illepidaria, Eublemma abrupt, Thalassodes sp., Lymantria sp., Eublemma versicolor, Aetholix flavibasalis and Eublemma sp. ; along with nearly 17 more unidentified species. The regularly noticed floral visitors were from the families of Syrphidae, Calliphoridae and Sarcophagidae and the identified species were Eristalinus arvorum , Lucilia sericata and Parasarcophaga dux. Apart from these there were presence of several other bugs, ants (Camponotus compressus), unidentified neuropterans and mantids (Odontimantis pulchra). The documented spider diversity from inflorescence consisted of Thomisus sp., Tetragnatha viridorufa, Cyrtophora cicatrosa, and Tetragnatha sp.
A field experiment was carried out at Kollengode area of Palakkad district to evaluate the efficacy of Beauveria bassiana (ITCC6063) WP 2%, fish –jaggery mixture 0.5%, azadirachtin 1%, buprofezin 25% EC 62.5 g a.i. ha-1, novaluron 10% EC 100 g a.i. ha-1, chlorantraniliprole 18.5%SC 30 g a.i. ha-1and Metarhizium anisopliae (Ma4) 20 g l-1, to suppress the pest attack on the inflorescence with a major focus on the caterpillar complex.
Single spray of each treatment was done on the selected mango trees and observations were recorded from the tagged inflorescence on fifth, tenth and fifteenth day after spraying. All the treatments were effective in reducing the pest. However, chlorantraniliprole 18.5% SC 30 g a.i. ha-1 was the superior treatment in reducing the pest population (4.11) followed by novaluron 10% EC 100 g a.i. ha-1 (5.22) and buprofezin 25% EC 62.5 g a.i. ha-1 (5.33) on five, ten and fifteen days after spraying. Among the biocontrol agents entomopathogenic fungi like Beauveria bassiana (ITCC6063) WP 2% (7.89) followed by Metarhizium anisopliae (Ma4) 20 g l-1(7.94), were found effective. Azadirachtin 1% (7.72) was also an effective treatment among the biorationals and gave maximum pest suppression at 15th day of spraying. Chlorantraniliprole 18.5%SC 30 g a.i. ha-1 recorded maximum fruit set per panicle (24.33) during the peanut stage followed by Novaluron 10% EC 100 g a.i. ha-1 (23.33) however, they were on par with each other.