Question

Black (stem) rust of wheat is caused by
a. Xanthomonas oryzae
b. Alternative solani
c. Ustilago nuda
d. Puccinia graminis

Answer 1

Hint: The stem, dark, and grain rusts are brought about by the parasite Puccinia graminis and are a critical illness influencing oat crops. Yield species that are influenced by the malady incorporate bread Wheaton, durum wheat, grain, and triticale. These illnesses have influenced grain cultivation since the beginning.

Complete answer:
> The stem, bark, and grain rusts are brought about by the growth of Puccinia graminis. P. graminis is an individual from the phylum Basidiomycota inside the realm of Fungi. The trademark rust shading on stems and leaves is run of the mill of overall stem rust just as any variety of this kind of organism. The stem rust growth assaults the pieces of the plant which are over the ground. Spores that land on green wheat plants structure a pustule that attacks the external layers of the tail. Contaminated plants produce fewer turners and set less seed, and in instances of serious disease, the plant may pass on. So, option D is correct.

> Xanthomonas oryzae pv. oryzae and Xanthomonas oryzae pv. oryzicola causes disease in rice. So, option A is incorrect.

> Loose smut of grain is brought about by Ustilago nuda It is an infection that can devastate an enormous extent of a grain crop. Free muck replaces grain heads with filth, or masses of spores which contaminate the open blossoms of sound plants and develop into the seed, without demonstrating any indications. So, option C is incorrect.

> Alternaria solani is a contagious microorganism that delivers an ailment in tomato and potato plants called an early curse. The microbe produces particular "bullseye" designed leaf spots and can likewise cause stem sores and natural product decay on tomato and tuber scourge on the potato. So, option B is incorrect.

Hence, the correct answer is option (D).

Note: The stem, dark, and oat rusts are brought about by the growth of Puccinia graminis and are a critical sickness influencing grain crops. Harvest species that are influenced by the malady incorporate bread wheat, durum wheat, grain, and triticale. These illnesses have influenced oat cultivating since the beginning. The yearly repeat of stem rust of wheat in North Indian fields was found by Prof. K.C. Mehta. Since the 1950s, wheat strains reared to be impervious to stem rust have gotten available. Fungicides viable against stem rust are accessible too.