Plant Pathology MCQ Question and Answer | Agriculture MCQ Question

The first scientist to find out the role of light in photosynthesis was Ingenhousz.
Jan Ingenhousz is yet another scientist who contributed to the discovery of photosynthesis. He was a Dutch chemist, biologist, and physiologist who performed important experiments in the late 1770s that proved that plants produce oxygen. Ingenhousz placed submerged plants in sunlight and then in the shade.

Plant disease was written by R. S. Singh.
The book mainly describes diseases of field crops, and several vegetable crop diseases are also included.
A major addition to the text is the inclusion of biological control measures for most diseases and the expansion of the information about phanerogamic plant parasites.

MLO and spiroplasma are mostly Phloem inhibiting.
A large group of plant-pathogenic, phloem-inhibiting bacteria was discovered by Japanese scientists in 1967. They are transmitted from plant to plant by phloem-feeding insect hosts and cause a variety of symptoms and considerable damage.
The spiroplasmas are mollicutes characterized by motility and helical morphology. They were discovered through studies on corn stunt and citrus stubborn diseases.
Mycoplasma-like organisms are generally considered to be somewhere between bacteria and viruses in size, shape and function.

The compost contains 0.89% of nitrogen.
FYM is farmyard manure and its nitrogen content is 0.50%.
Night soil is nothing but human excreta which is used as fertilizer and it contains 5.5% of nitrogen approximately.
Bird Guano is the accumulated excrement of seabirds and bats, and is a highly effective fertilizer, it contains 7% - 8% of Nitrogen.

In Uredinales (rust fungi) basidia usually bear four numbers of basidiospores.
A basidiospore is a reproductive spore produced by Basidiomycete fungi, a grouping that includes mushrooms, shelf fungi, rusts and smuts.
Typically, four basidiospores develop on appendages from each basidium, of which two are of one strain and the other two of its opposite strain.

Complex fertilizer contains more than one major nutrient in a combined form.
Complex fertilizers contain two or three primary plant nutrients of which two primary nutrients are in chemical combination. These fertilizers are usually produced in granular form. eg. Diammonium phosphate, nitro phosphate and ammonium phosphate.

The discovery of the first defense activator compound CGA 245704 is an innovative approach to disease control in cereal crop(s).

Early blight of potato produces Conidia.
Conidium is a type of asexual reproductive spore of fungi usually produced at the tip or side of hyphae or on special spore-producing structures called conidiophores.
Early blight of potatoes is caused by the fungal pathogen Alternaria solani. The disease affects leaves, stems, and tubers and can reduce yield, tuber size, storability of tubers, quality of fresh-market and processing tubers, and marketability of the crop.

Potatoes are cultivated by Buds on tubers.
Stem tubers form thickened rhizomes (underground stems) or stolons (horizontal connections between organisms); well-known species with stem tubers include the potato and yam.
Potatoes are mainly propagated by vegetative methods (cloning). Potato tubers have nodes or eyes from which the new growth begins. The new stems growing from each eye are called sprouts which give rise to the new plant. Vegetative seeds can be either a whole tuber or a cut tuber.