ICAR AIEEA PG Entomology 14 July 2023 Shift-1 Paper

Host plants of the lac insect (Kerria lacca / Laccifer lacca):

• The major host trees for the Rangeeni strain are Palas (Butea monosperma), Ber (Ziziphus mauritiana), and Babul (Acacia nilotica), along with Pigeonpea (Cajanus cajan).
• The premier host plant for the superior Kusmi strain is Kusum (Schleichera oleosa), along with Palas and Ber.
• Trees in list (D) like citrus, avocado, and guava are not lac hosts. Hence, (A) and (B) only represent genuine sets of common host plants.

Nature and composition of lac and shellac:

• Statement (I) is correct: Shellac is refined processed lac, which is a natural resinous secretion produced primarily by the sedentary female lac insect (Laccifer lacca / Kerria lacca) covering twigs of host trees.
• Statement (II) is incorrect: Lac/shellac is primarily composed of polyesters of hydroxy fatty acids and sesquiterpenic acids (aleuritic acid and shellolic acid, ~$65-70\%$ resin), lac dye (~$1-2\%$), lac wax (~$5-6\%$), and mineral matter; it does NOT contain gum Arabic (which is a plant exudate from Acacia senegal).

Biocontrol agents and their target pests:

• Rodolia cardinalis (Vedalia beetle): The classical predator of the cottony cushion scale (Icerya purchasi) -> (III).
• Cryptolaemus montrouzieri (Australian ladybird beetle): An effective predator of mealybugs, especially the pink hibiscus mealybug (Maconellicoccus hirsutus) -> (I).
• Telenomus remus: An effective scelionid egg parasitoid of armyworms, including the fall armyworm (Spodoptera frugiperda) -> (II).
• Zygogramma bicolorata (Mexican beetle): A chrysomelid biocontrol agent introduced against the invasive congress grass weed (Parthenium hysterophorus) -> (IV).

Option analysis:
(A) The foundational textbook Biological Insect Pest Suppression by Harry C. Coppel and James W. Mertins was published in 1977.