Which of the following nutrients is not present in plant tissues in excess of 10 m mole Kg^-1 of dry matter?

Which of the following essential elements function as components of energy-related chemical compounds in plants?

a. Magnesium b. Phosphorus c. Carbon d. Nitrogen

Which of the following elements is the major constituent of proteins, vitamins, hormones and nucleic acids?

Which of the following is not a beneficial element that is required by higher plants?

Which of the following macronutrients are absorbed from the soil as mineral nutrition?

a. Carbon b. Nitrogen c. Hydrogen d. Phosphorus

Which of the following is not a criteria of essentiality of an element for the growth of a plant?

a. The requirement of the element must be specific. b. For supporting normal growth and reproduction of the plant, the element must be absolutely essential. c. The element should be indirectly involved in the metabolism of the plant.

Which of the following elements activates enzymes that are involved in photosynthesis, respiration and nitrogen metabolism?

Which of the following essential elements is present in cysteine and methionine?

Which of the following elements plays an important role in the opening and closing of stomata?

Which of the following scientists, in 1860, demonstrated the technique of hydroponics that was the technique of growing plants in a nutrient solution?

Which of the following is essential for the overall metabolism in plants and is associated with certain enzymes involved in redox reactions?

Chlorosis is the loss of chlorophyll. It causes yellowing of leaves. It is not caused due to the deficiency of which of the following elements?

Which of the following is a limiting nutrient for both natural and agricultural ecosystems?

The morphological changes that are indicative of element deficiency are called deficiency symptoms. The deficiency symptoms of which of the following elements are visible first in the senescent leaves?

a. Manganese b. Iron c. Potassium d. Magnesium

Which of the following are free-living, nitrogen-fixing aerobic microbes?

a. Rhodospirillum b. Bacillus c. Azotobacter d. Beijernickia

Which of the following bacteria are chemoautotrophs?

a. Nitrococcus b. Pseudomonas c. Thiobacillus d. Nitrobacter

On the roots of which of the following plants does the microbe Frankia produce nitrogen-fixing nodules?

Which of the following statements is/are false?

a. The symptom of manganese toxicity in a plant is the appearance of blue spots surrounded by chlorotic veins. b. Toxicity levels of an element may vary in different plants and are difficult to identify. c. Mineral salts are translocated through xylem along with the ascending stream of water.