Three of the major elements needed for good plant growth are nitrogen (N), phosphorus (P), and potassium (K) - Leaving Cert Agricultural Science - Question b - 2018

Deficiency in nitrogen leads to slow growth and a yellowing of the leaves, indicating a lack of green color often referred to as chlorosis.

Phosphorus is vital for root growth, energy transfer, and flowering or seed formation, playing a key role in various metabolic processes.

Phosphorus deficiency results in stunted growth and may cause leaves to develop a blue color or a lack of flowers, hindering reproduction.

Potassium helps in protein synthesis and translocation of nutrients, enhancing the plant's overall resistance to diseases and stress.

A potassium deficiency can lead to reduced yield, poor growth, and symptoms like scorching of leaf edges or lodging, negatively impacting plant development.

To demonstrate the effect of nutrient deficiency, sterilize test tubes or containers and plant seedlings in two tubes: one containing the complete nutrient solution and the other with the nutrient minus the element being tested. Ensure proper aeration and cover to prevent algae growth. After a minimum of two weeks, measure and compare the growth and overall health of the plants to observe the effects of the nutrient deficiency.