The scientist who used nutrient culture solution in hydroponic cultures was

The correct option is Knop.

Hydroponics is the technique of growing plants in a soil-free medium using a nutrient-rich water solution. Wilhelm Knop, a prominent German agricultural chemist, is widely recognized for his pioneering work in this field during the 1860s.

Knop formulated a specific nutrient culture solution, frequently referred to as Knop's solution, which contained key inorganic salts in precise proportions. This solution provided the essential macro- and micro-nutrients required for the complete growth and development of plants to maturity without the need for soil.

By utilizing this culture solution in his experiments, Knop demonstrated that soil is not indispensable for plant growth as long as the necessary mineral nutrients are dissolved and available in a water-based medium, thereby establishing the scientific foundation for modern hydroponics.