Quiz: Assistant Agriculture Officer: Plant Pathology & Entomology

Correct Answer: Erickson
Erickson first described heterokaryosis in fungi, a key mechanism contributing to their genetic variability. This discovery was foundational to understanding fungal adaptation.

Correct Answer: Melampsora lini
Autoecious rusts like Melampsora lini complete their entire life cycle on a single host species (flax). Other Puccinia species listed are heteroecious, requiring alternate hosts.

Correct Answer: Alternaria
Alternaria species are facultative parasites or saprophytes, able to live on dead matter or infect plants. Albugo, Erysiphe, and Peronospora require a living host (obligate parasites).

Correct Answer: Alternaria alternata
Tentoxin, a phytotoxin causing chlorosis and spots, is specifically produced by the fungus Alternaria alternata. It disrupts chloroplast function in susceptible plants.

Correct Answer: Spheroidal
Cauliflower Mosaic Virus (CaMV) particles (virions) have an isometric or spheroidal (roughly spherical) shape. This morphology is characteristic of the Caulimovirus genus.

Correct Answer: Sclerospora graminicola
The specific causal agent of downy mildew (green ear disease) in bajra (pearl millet) is Sclerospora graminicola. Other listed fungi cause downy mildews in different crops.

Correct Answer: only RNA or only DNA
A fundamental characteristic of viruses is possessing a genome of either DNA or RNA, never both together. This nucleic acid can be single or double-stranded.

Correct Answer: Trichoderma harzianum
Trichoderma harzianum is a very common and widely studied mycoparasite, known for parasitizing other fungi. It is extensively used as a biocontrol agent in agriculture.

Correct Answer: Italian bee - Melipona iridipennis
The Italian bee is Apis mellifera ligustica, while Melipona iridipennis is a stingless bee species. The other pairs correctly match common bee names to their Apis species.

Correct Answer: Azodrin-monocrotophos
Azodrin is a widely known trade name for the organophosphate insecticide monocrotophos. The other options incorrectly pair trade names with active ingredients.

Correct Answer: Thrips
Thrips possess unique asymmetrical mouthparts used to rasp or puncture plant surfaces and then suck the released cell contents. This differs from the piercing-sucking mouthparts of aphids, leafhoppers, and whiteflies.

Correct Answer: Rachel Carson
Rachel Carson authored the influential book 'Silent Spring' (1962), which highlighted the ecological dangers of pesticides like DDT. The book significantly boosted the environmental movement.

Correct Answer: Diamond Back moth
Mustard serves as an effective trap crop for the Diamondback Moth (Plutella xylostella) in cabbage fields. The pest is preferentially attracted to mustard, reducing infestation on the main crop.

Correct Answer: Fruit fly
Mango fruit flies (Bactrocera spp.) pupate in the soil beneath the trees. Raking or disturbing the soil exposes these pupae, destroying them and reducing the next generation's population.

Correct Answer: Uvarov
Sir Boris Uvarov formulated the 'phase theory' explaining locust polymorphism. He showed locusts shift between solitary and gregarious phases based on population density.

Correct Answer: Philosamia ricini
The Eri silkworm, which produces eri silk, is scientifically known as Philosamia ricini (or Samia cynthia ricini). Bombyx mori is the mulberry silkworm.

Correct Answer: ETL
The Economic Threshold Level (ETL) is the pest density that triggers control actions. Action at ETL aims to prevent the population from reaching the Economic Injury Level (EIL).

Correct Answer: Anguina
Anguina tritici, the wheat seed gall nematode, was the first plant-parasitic nematode discovered and described by Needham in 1743. It causes galls in wheat kernels.

Correct Answer: Xiphinema
Grapevine Fanleaf Virus (GFLV) is transmitted specifically by the dagger nematode, Xiphinema index. This nematode acts as a vector, spreading the virus between grapevine plants.