’All elements that are present in a plant need not be essential to its survival’. Comment.

The statement "All elements that are present in a plant need not be essential to its survival" reflects the concept that while plants may accumulate various elements from the environment, not all of these elements are critical for their survival and growth. This statement highlights the distinction between essential and non-essential elements in plant nutrition.

In plant nutrition, essential elements are those that are required by plants in relatively large quantities for normal growth, development, and reproduction. These essential elements include macronutrients such as nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S), as well as micronutrients or trace elements such as iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), boron (B), molybdenum (Mo), and chlorine (Cl). These elements play vital roles in various physiological processes within the plant, such as photosynthesis, respiration, cell division, and enzyme activation.

However, plants may also accumulate non-essential elements, which are elements that are not required for normal plant growth and development. These non-essential elements may include heavy metals such as lead (Pb), cadmium (Cd), mercury (Hg), and arsenic (As), as well as other elements that are present in the environment but do not have known physiological functions in plants.

While non-essential elements may be taken up by plants through processes such as root uptake or atmospheric deposition, their presence does not necessarily contribute to the plant's survival or productivity. In fact, high levels of certain non-essential elements can be toxic to plants, inhibiting growth and causing physiological disorders or even plant death.

Therefore, while plants may accumulate a wide range of elements from the environment, the essential elements are the ones that are critical for their survival and overall health, while non-essential elements may have little to no impact on their well-being and may even be detrimental in excessive concentrations.