DRR Dhan 77

Background:

The escalating global water crisis is the primary impetus behind the development and adoption of aerobic rice varieties, offering a sustainable alternative to the water-intensive traditional lowland rice cultivation, which consumes a staggering 30% to 50% of the world’s freshwater. Major rice-growing regions are grappling with severe water scarcity due to rapidly declining groundwater tables from over-extraction, increasingly erratic rainfall patterns and prolonged droughts driven by climate change, and heightened competition for water resources from urbanization and industrialization. Traditional lowland rice varieties, accustomed to anaerobic soil conditions, perform poorly in non-flooded environments, experiencing significant yield reductions, increased susceptibility to weeds that proliferate without standing water, and challenges in nutrient management due to altered soil chemistry. In response, "aerobic rice" emerged as a system where specially developed rice varieties are grown in well-drained, non-puddled soils, akin to other cereals, aiming to drastically cut water consumption while maintaining viable yields. However, despite its promise, widespread adoption faces several critical hurdles. A persistent yield gap exists, as aerobic rice often produces lower yields compared to optimally managed flooded systems, making it less attractive for farmers. Effective and sustainable weed control remains a significant challenge, necessitating integrated management strategies beyond mere herbicide application. Optimizing nutrient uptake and application, particularly for nitrogen, phosphorus, and micronutrients like zinc, is complex in aerobic soils, requiring tailored recommendations. Furthermore, while designed for water scarcity, some aerobic varieties can still be vulnerable to severe drought or heat stress during crucial growth stages, and continuous aerobic conditions may alter long-term soil health. Continuous breeding efforts are crucial to develop new varieties that combine high yield potential with enhanced water- and nutrient-use efficiency, alongside pest and disease resistance. Finally, overcoming farmer hesitation and facilitating effective knowledge transfer through robust extension services and practical demonstrations are paramount for successful, widespread implementation of this vital agricultural innovation, ultimately contributing to global food security in a water-stressed world.

Technology Details:

The Variety DRR Dhan 77 (IET 28636) (RP 6361-RAF-252-GSR-IR1-DQ146-L18-Y1) was selected from IRRI, Philippines bred line GSR-IR1-DQ146-L18-Y1. We have evaluated this line at ICAR-Indian Institute of Rice Research, Rajendranagar, Hyderabad under station trial and identified considering semi dwarf plant height, early duration, long slender grain type and yield. As a result, the line IET 28636 (RP 6361-RAF-252-GSR-IR1-DQ146-L18-Y1) was nominated to AICRPR, which has performed exceedingly well in aerobic direct seeded conditions of the states of Bihar, Gujarat and Tamil Nadu under AICRPR aerobic trials over 3 years. Overall mean yield of the proposed three zones viz., Zone III, Zone VI and Zone VII, the proposed variety surpassed the national check, zonal check as well as local check. DRR Dhan 77 (IET 28636) is early duration, erect, highly vigorous, non-lodging, non-shattering and complete panicle exertion. The plant comes to flowering within 85-90 days, plants are 92 cm tall, and it produces good biomass, long panicles, and has long slender grains with white kernel. It possess excellent grain quality attributes of Hulling % (79.8%), Milling (56.6%) and Head Rice Recovery (55.0%), Grain chalkiness (VOC), amylase content of 24.4% and GC of 33.

PPV&FRA Applied: Ack No. REG/2025/0839