Scientific study finds DSSAT soyabean yield estimates inconsistent with ground reality

Chhatrapati Sambhajinagar: A scientific study by experts from the Parbhani-based Vasantrao Naik Marathwada Krishi Vidyapeeth has found that DSSAT-based technical yield estimates used for soyabean crop insurance assessment in Dharashiv district do not reflect the ground reality, prompting district collector Keerthi Kiran Pujar to urge Maharashtra govt to ensure fair compensation to farmers under the Pradhan Mantri Fasal Bima Yojana (PMFBY).

In a letter to the principal secretary (agriculture) sent on Tuesday, Pujar called for placing the issue before the Central Technical Advisory Committee and recommended that compensation be based on actual mandal-wise productivity rather than simulated yields generated through DSSAT (decision support system for agrotechnology transfer) modelling.

The collector said Dharashiv had witnessed unprecedented rainfall during the 2025 kharif season, severely impacting soyabean crops, which account for nearly 80% of the district’s sowing area. While the average kharif sowing area is 5.4 lakh hectares, crops were sown on 5.7 lakh hectares last season.

Under PMFBY 2025-26, as many as 4.96 lakh farmers insured crops on over 3.9 lakh hectares.

According to official data cited in the letter, the district recorded 279.6 mm rainfall in May 2025 — the highest in 26 years — and 220 instances of heavy rainfall between June and Oct, including 141 in Aug and September. Seasonal rainfall stood at 159% of average, coinciding with critical crop stages like flowering and pod filling, leading to extensive damage due to waterlogging, fungal infections, grain rot, and crop washouts.

Field inspections conducted under natural calamity assessment showed that 5.8 lakh hectares out of 6.2 lakh hectares surveyed — nearly 92% — were affected.

The collector also flagged serious discrepancies in crop cutting experiments (CCEs), which determine insurance payouts. Of the 504 experiments planned, the insurer objected to 368. After hearings, 149 were rejected for delays, while 200 objections were dismissed. The insurer later challenged the decision at the state level, where compensation calculations considered a 50% weightage to CCE data and 50% to DSSAT estimates.

Pujar said, “While actual crop cutting experiments showed soyabean productivity of only three to four quintals per hectare, the DSSAT-based technical assessment reflected yields of 10 to 12 quintals per hectare in several revenue circles, thereby reducing estimated losses to barely 10%.”

The issue had earlier been raised by Tuljapur MLA Ranajagjitsinh Patil, following which the Parbhani-based agricultural university conducted a detailed analysis comparing CCE data, DSSAT estimates and field conditions.

The study, cited in the collector’s letter, found that DSSAT modelling failed to account for prolonged waterlogging, pest infestation, grain deterioration and adverse local climatic conditions, which led to a sharp decline in actual yields.