Which of the following is a component of nitrogenase and nitrate reductase?

$A$ plant requires potassium for

$A$ plant requires magnesium for

The deficiencies of micronutrients not only affect the growth of plants but also vital functions such as photosynthetic and mitochondrial electron flow. Among the list given below,which group of three elements shall affect most,both photosynthetic and mitochondrial electron transport?

Which of the following are considered as the roles of iron $(Fe)$ in plants?
$I.$ Important constituent of cytochrome
$II.$ Activator of catalase
$III.$ Essential for chlorophyll synthesis
Choose the correct option

Sulfur,as an essential nutrient,significantly increases the growth and productivity of which type of crops?