Phosphorus (P) use efficiency in rice is linked to tissue-specific biomass and P allocation patterns

Area of Science:

• Agricultural Science
• Plant Physiology
• Nutrient Management

Background:

• Phosphorus (P) is a critical, non-renewable nutrient essential for plant growth.
• Depletion of global phosphorus reserves necessitates enhanced P use efficiency in agriculture.
• Plants exhibit adaptive mechanisms to cope with phosphorus deficiency, including altered P acquisition and utilization.

Purpose of the Study:

• To investigate tissue-specific biomass and P allocation patterns in rice cultivars under varying P availability.
• To identify key factors contributing to phosphorus use efficiency (PUE) in different rice varieties.
• To compare P uptake, utilization, and remobilization efficiencies among selected rice cultivars.

Main Methods:

• Six rice cultivars were initially grown in solution culture and subjected to adequate or deficient P conditions.
• Plants were dissected into various tissues/organs at different developmental stages (30, 40, 50 days).
• Two specific cultivars (Super Basmati and PS-2) were further evaluated in soil experiments with contrasting P levels until maturity.

Main Results:

• Rice cultivars PS-2 and Basmati-2000 demonstrated higher P uptake, utilization efficiency, and internal remobilization under P omission.
• Young leaves and roots acted as primary sinks for P, while stems and mature leaves served as P sources during P deficiency.
• Significant variations in tissue-specific biomass and P accumulation were observed among the tested cultivars.

Conclusions:

• Biomass allocation and P accumulation patterns across different plant tissues are critical determinants of P efficiency in rice.
• Internal P remobilization plays a vital role in maintaining plant growth and productivity under phosphorus-limited conditions.
• Identifying and breeding rice cultivars with efficient P utilization and remobilization strategies is essential for sustainable agriculture.