Phosphorus (P)

Phosphorus (P)

Why it Matters? 

  • The National Institute of Plant Genome Research (NIPGR) has developed gene-edited japonica rice using CRISPR-associated protein 9 (CRISPR-Cas9) technology to enhance phosphate uptake and transport, resulting in up to 40% higher yield even with just 10% of the recommended phosphate fertilizer, marking a breakthrough in sustainable agriculture. 

What You Should Know? 

  • Phosphorus (P) is essential for root development, tillering, early flowering, and ripening in crops. 

  • It is mobile in the plant but immobile in the soil, making timely application crucial. 

  • Phosphorus deficiency symptoms include stunted, dark green plants with erect leaves, poor tillering, and delayed flowering. 

  • P is often deficient in acidic, alkaline, sandy, or degraded soils with high P fixation (due to Fe, Al, Ca, or Mg). 

  • Rice crops absorb ~6.4 kg P₂O₅ (2.8 kg P) per ton of grain (4.4 kg in grain, 2.0 kg in straw). 

  • Major P fertilizers: Single super phosphate (SSP), Triple super phosphate (TSP), Diammonium phosphate (DAP), Ammonium polyphosphate (APP). 

  • P fertilizer uptake efficiency is only 15–20%, the rest is lost via runoff or fixed in the soil. 

 Japonica: 

  • It is characterized by short to medium, roundish grains that are sticky, thick, harder, and have low amylose content (0–20%), making them ideal for sushi and glutinous rice. 

  • Japonica is one of the two main subspecies of Oryza sativa (the other being Indica), predominantly grown in temperate and cooler subtropical regions. 

  • Grain features include awnless to long-awned spikelets, non-shattering grains, and naturally gluten-free properties despite the name "glutinous rice." 

  • Climatic suitability: Japonica rice thrives in temperate zones and cooler subtropics, mainly cultivated in Japan, China, Korea, Vietnam, and parts of Indonesia. 

  • Each Japonica cultivar is selectively bred for specific traits, allowing adaptability to diverse agro-climatic conditions and culinary preferences.