__________ is the most suitable fertiliser for paddy.

ANS:B - Ammonium sulphate

The most suitable fertilizer for paddy cultivation is ammonium sulfate. Paddy, or rice, is a crop that benefits from nitrogen and sulfur fertilization. Ammonium sulfate provides both nitrogen and sulfur, making it an ideal fertilizer for paddy fields. The ammonium form of nitrogen in ammonium sulfate is readily available to paddy plants, promoting vegetative growth and enhancing grain yield. Additionally, sulfur is an essential nutrient for rice plants, particularly in areas with sulfur-deficient soils, as it plays a crucial role in protein synthesis and overall plant health. So, the correct option is: Ammonium sulfate Ammonium sulfate (NH4)2SO4 is an inorganic salt that is commonly used as a nitrogen and sulfur fertilizer in agriculture. It is a white, crystalline solid that is highly soluble in water. Here are some key points about ammonium sulfate:

1. Composition: Ammonium sulfate consists of two ammonium ions (NH4⁺) and one sulfate ion (SO4²⁻). It is a source of both nitrogen and sulfur nutrients for plants.
2. Nitrogen Content: Ammonium sulfate typically contains about 21% nitrogen by weight, with all of the nitrogen present in the ammonium form (NH4⁺). This form of nitrogen is readily available to plants and can be quickly absorbed through their roots.
3. Sulfur Content: Ammonium sulfate also provides sulfur, an essential nutrient for plant growth. It contains about 24% sulfur by weight in the sulfate form (SO4²⁻). Sulfur is important for various biochemical processes in plants, including the synthesis of amino acids, proteins, and vitamins.
4. Acidifying Effect: Ammonium sulfate has a slightly acidic pH when dissolved in water, which can help to acidify alkaline soils. This can be beneficial for crops that prefer acidic growing conditions, such as certain types of fruits, vegetables, and ornamental plants.
5. Application: Ammonium sulfate is commonly used as a fertilizer for a wide range of crops, including grains, legumes, vegetables, fruits, and turfgrass. It can be applied to the soil directly or dissolved in water for foliar application. It is particularly effective for crops that have a high demand for nitrogen and sulfur, such as rice, corn, and potatoes.
6. Benefits: The dual nutrient content of nitrogen and sulfur in ammonium sulfate makes it a valuable fertilizer for promoting plant growth, improving crop yield, and enhancing the quality of agricultural products. It is also relatively low in cost compared to some other nitrogen fertilizers.

Overall, ammonium sulfate is a versatile fertilizer that provides essential nutrients to plants, promotes healthy growth, and contributes to sustainable agriculture practices. Its balanced nitrogen-sulfur content makes it particularly suitable for crops with high nutrient requirements, such as paddy (rice), and for soils that are deficient in sulfur.