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1. What is a virus? a) A submicroscopic entity that replicates only in living cells and consists of either DNA or RNA. b) A type of bacteria. c) A small animal. d) None of the above. 2. What is the term for a completely assembled infectious virus particle? a) Nucleic acid. b) Virus. c) Capsid. d) Virion. 3. What is the size range of plant viruses? a) 2-20nm. b) 20-2000nm. c) 2000-5000nm. d) None of the above. 4. What is the protein coat of a viral particle called? a) Nucleic acid. b) Capsid. c) Virion. d) Envelope. 5. Are viruses obligate intracellular parasites? a) Yes. b) No. c) Sometimes. d) None of the above. 6. What percentage of a virus is made up of nucleic acid? a) 5-40%. b) 60-95%. c) 100%. d) None of the above. 7. What is the nucleic acid content of elongated viruses as compare to spherical viruses? a) High. b) Low. c) It depends on the virus. d) None of the above. 8. What are viruses called when their genome is present in different particles? a) Unipartite viruses. b) Multi...

1. The vegetative body of fungi is called as- a) Hypha b) Spore c) Mycelium d) Rhizomorph 2. Which type of hyphae in fungi have scattered nuclei in the cytoplasm? a) Aseptate hyphae b) Septate hyphae c) Coenocytic hyphae d) Branched hyphae 3. The thicker root-like aggregates in fungi is called as- a) Mycelium b) Hypha c) Rhizomorphs d) Sclerotia 4. The hard roundish or amorphous structure in fungi is known as- a) Mycelium b) Hypha c) Rhizomorphs d) Sclerotium 5. The mat-like structures in fungi that contain the fruiting bodies is called as? a) Mycelium b) Hypha c) Stroma d) Sporangium Answers: 1. c 2. c 3. c 4. d 5. c

1. Who discovered that fire blight of apple and pear was caused by a bacterium? a) Wakker b) E.E. Smith c) T.J. Burrill d) None of the above Answer: c) T.J. Burrill 2. Which disease did Wakker discover was caused by a bacterium? a) Fire blight of apple and pear b) Yellows disease of hyacinth c) Both a and b d) None of the above Answer: b) Yellows disease of hyacinth 3. Who is considered the Father of Phytobacteriology? a) Wakker b) E.E. Smith c) T.J. Burrill d) None of the above Answer: b) E.E. Smith 4. When did E.E. Smith start contributing to the discovery of plant diseases caused by bacteria? a) 1882 b) 1883 c) 1895 d) None of the above Answer: c) 1895 5. Which of the following is NOT true about T.J. Burrill? a) He discovered that fire blight of apple and pear was caused by a bacterium. b) He contributed to the discovery of plant diseases caused by bacteria. c) He is considered the Father of Phytobacteriology. d) None of the above Answer: c) He is considered the Father of Phytobacte...

  Bacteria as Plant Pathogens In 1882, T.J. Burrill of USA for the first time reported that a plant disease (fire blight of apple and pear) was caused by a bacterium (now known as Erwinia amylovora). Wakker (1883) showed that yellows disease of hyacinth was also caused by a bacterium. E.E. Smith of USA is regarded the most outstanding and main contributor to the discovery of most of plant diseases due to bacteria since 1895. He is considered Father of Phytobacteriology for his discoveries and methodologies. Smith’s name is still remembered as he resolved the controversy with the German scientist A. Fischer (1897, 99) who did not agree that bacteria were the causes of diseases in plants. Smith was also among the first to notice and study the crown gall disease (1893, 1894). He considered crown gall similar to cancerous tumors of humans and animals. Later in 1977, it was demonstrated by Chilton and his team that the crown gall bacterium, Agrobacterium tumefaciens transforms the norma...

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