Infections of Plants (GATE - XL)

Correct answer. Diamond spot disease of Musa acuminata is caused by Cercospora hayi.

Correct answer. In carrot, Cottony rot disease is caused by the fungal species- Sclerotinia sp. (S. minor, S. Sclerotiarum).

Correct answer. Xanthomonas campestris causes Fuscous blight disease in beans.

This option is correct because in apple, Kernel blight disease is caused by bacteria- Pseudomonas syringae pv. syringae and Basal glume rot is caused by bacteria- Pseudomonas syringae pv. atrofaciens.
Anthracnose, Dwarf bunt and Leaf rust are caused by fungal pathogens- Collectotrichum cereale, Tilletia controversa and Puccinia hordei, respectively, in apple.

Correct answer. The method enabled the highly sensitive detection of a number of morphologically different viruses in purified preparations and in unclarified extracts of herbaceous hosts and of infected crop plants are employed for the detection of plant viral diseases like- Electron microscopy, Serological assay, Agglutation assay, Enzyme-Linked Immunoserological Assay (ELISA), Nucleic acid hybridisation assay (NAHA), etc.

Correct answer. In coffee, warty berry disease is caused by Botrytis cinerea.

Correct answer. Nucleic acid based detection systems were greatly improved following the development of the polymerase improved following the development of the polymerase chain reaction (PCR). PCR is able to detect pathogens by targeting their genetic material (RNA/DNA).
Real time PCR (RT-PCR) is used to combine amplification, detection and quantification in a single step for RNA as target.
Immunocapture PCR (IC-PCR) is used to combine the advantages of serology and is a very sensitive method of detection the diseases by targeting both DNA and RNA as genetic material.
Multiplex PCR (IC-RT-PCR) allows for simultaneous and sensitive detection of different DNA and RNA as genetic material in the detection of plant diseases in a single reaction.

This option is correct because in apple, Perennia canker disease is caused by Neofabraea perennans, Fruit decay is caused by Phomopsis mali, Pink mold rot disease is caused by Trichothecius roseum and Zonate leaf spot disease is caused by Grovesinia pyramidalis.

P. Bunchy top disease of banana is caused by Banana bunchy top virus (BBTV). Pyricularia grisea fungus causes Pitting disease in banana.
Q. Pseudostem heart rot disease of banana is caused by Fusarium moniliforme. Pseudomonas solanacearum causes Bugtok disease in banana.
R. Rhizome rot disease of banana is caused by Erwinia sp. like- E. carotovora, E. chrysanthemi.
Hence, both P and Q statements are false.

Correct answer. In rose, Spot anthracnose disease is caused by the fungus- Sphaceloma rosarum.
In the 19^th century, several outbreaks of vine diseases occurred among the Vitis vinifera vines of the classicial European wine regions. After the downy mildew had struck, botany professor Pierre-Marie-Alexis Millardet of the University of Bordeaux studied the disease in vineyards of the Bordeaux region. In 1885, Millardet published your findings on mildew of grapes and introduced Bordeaux mixture to control downy mildew of grapes.
Crop rotation may be an effective means to prevent a parasitic population from becoming well-established, as an organism affecting leaves would be starved when the leafy crop is replaced by a tuberous type, etc. Other means to undermine parasites without attacking them directly may exist.

Correct answer. Stripe disease of wheat is caused by Cochliobolus sativus. Wheat’s false eyespot disease is caused by Hymenula cerealis.

Correct answer. Areolate leaf spot in citrus is caused by Rhizoctonia solani.

Correct answer. In maize, Stewart's disease is caused by Erwinia stewartii and Holcus spot disease is caused by Pseudomonas syringae.

Correct answer. Dry rot disease is caused by Ashbya gossypii and Nematospora coryli in citrus.

Correct answer. Agrobacerium rhizogenes in apple causes hairy root disease.