Red-Rot-Resistant Co-20016 Cleared for Release as UP Sugar Output Falls from 126.4 to 89.5 Lakh Tonnes

The news

New Delhi. Uttar Pradesh, India’s largest sugarcane-growing State, has seen its sugar output fall from 126.4 lakh tonnes to 89.5 lakh tonnes between 2019-20 and 2025-26, The Indian Express reports. Sugar years run from October to September. The main cause is that Co-0238, also called Karan 4, the variety grown on most of the State’s cane area, has become susceptible to red rot, a fungal disease. The resulting yield losses have reduced the cane crushed by UP’s 120-odd sugar mills by more than a fifth in six years. Figures from the State’s Sugar Industry and Cane Development Department show cane crushed falling from 1,118.02 lakh tonnes in 2019-20 to 878.12 lakh tonnes in 2025-26. UP’s Assembly elections are due in February-March 2027. The industry is now relying on a new variety, Co-20016 (Karan 20), developed by the Indian Council of Agricultural Research’s Sugarcane Breeding Institute (ICAR-SBI) at Coimbatore. On May 27 a Varietal Identification Committee under the All-India Coordinated Research Project (AICRP) on Sugarcane picked it as a potential replacement for Co-0238. An official said it will go next to the Central Varietal Release Committee, expected to meet in October. Once it is approved and notified for commercial cultivation, farmers can plant it in the spring (February-March), summer (April-May) or autumn (mid-September to mid-November) seasons. In August 2023 the Indian Sugar & Bio-energy Manufacturers Association (ISMA) and ICAR-SBI began joint trials of improved varieties at mill locations in subtropical India (UP, Uttarakhand, Bihar, Haryana and Punjab) and tropical India (Maharashtra, Karnataka, Tamil Nadu, Gujarat, Madhya Pradesh, Andhra Pradesh and Telangana). In the subtropical trials, Co-20016 and Co-21012 were tested for three years over two plant crops and one ratoon crop, which is the regrowth from stubble after harvest. Sixteen mills took part, 11 of them in UP. ISMA Director General Deepak Ballani called the results “very encouraging”. The AICRP trials are complete for Co-20016 and under way for Co-21012. At ISMA’s trial sites, Co-20016 gave a three-year average yield of 144.6 tonnes per hectare against 116.4 tonnes for Co-0238. Its mean sucrose content in cane juice at ten months was 18.7%, against 18.3%. Most important, it is resistant to red rot, and specifically to the highly virulent ‘CF13’ pathotype of the fungus Colletotrichum falcatum. A pathotype is a strain of a pathogen that differs in which plant varieties it can infect. When Co-0238 was released in 2009 it was rated moderately resistant to the then-prevalent pathotypes CF07 and CF08. “The CF13 pathotype emerged due to the intensive monoculture planting of Co-0238 in UP as well as other sub-tropical states,” said Dr. Bakshi Ram, former ICAR-SBI director, who bred Co-0238. As the fungus changed, the variety “suffered varietal breakdown”. He said he had warned against over-cultivation, especially in the waterlogging-prone central, eastern and Terai belts of UP, where wet fields help red rot spread, but “neither the mills nor farmers followed my advice”. The syllabus link is GS3 on cropping patterns, agricultural research and technology, and farm support prices.

Static syllabus linkage

1. Red rot is a fungal disease often called the cancer of sugarcane. Red rot is caused by the fungus Colletotrichum falcatum (sexual stage Glomerella tucumanensis). It infects the stalk, turns the internal tissue red with white patches, gives off a sour smell and causes leaves to wither and the cane to dry. It spreads mainly through infected setts (the stem cuttings used for planting), and through water, soil and crop residue. Waterlogging and high humidity favour it. Control depends on resistant varieties, healthy seed cane, crop rotation and destroying infected clumps, since chemical control is of limited use once the stalk is infected.
2. The ‘Co’ prefix marks canes bred at Coimbatore. The Sugarcane Breeding Institute at Coimbatore, now under ICAR, was established in 1912. Varieties bred there carry the prefix ‘Co’ followed by the year of the cross and a number, so Co-0238 and Co-20016 are Coimbatore canes. The institute’s early work crossing the noble cane Saccharum officinarum with the wild Saccharum spontaneum produced varieties suited to north India. Varieties are tested under the All India Coordinated Research Project on Sugarcane and released by the Central Varietal Release Committee, and are then notified under the Seeds Act, 1966.
3. Monoculture creates genetic vulnerability. When a single variety covers most of a region, a pathogen that overcomes that variety’s resistance can spread across the whole area. Plant breeders call this varietal breakdown. The standard remedy is varietal diversity: several varieties with different resistance genes, replaced every few years. The Irish potato famine and the southern corn leaf blight in the United States in 1970 are the classic cases of genetic uniformity turning a disease into a disaster.
4. Cane pricing combines a central FRP and State advised prices. The Fair and Remunerative Price (FRP) of sugarcane is fixed by the Central Government under the Sugarcane (Control) Order, 1966, issued under the Essential Commodities Act, 1955, on the recommendation of the Commission for Agricultural Costs and Prices. The FRP is linked to a basic sugar recovery rate, with a premium for higher recovery. Several States, including Uttar Pradesh, announce a higher State Advised Price (SAP) that mills in the State must pay. Sugar output also matters for the ethanol blending programme, because mills divert cane juice and B-heavy molasses to ethanol, which reduces the sugar they produce.

Why UPSC loves this

1. Prelims has asked about crop diseases and research institutions. UPSC has tested knowledge of crop diseases, their causal organisms, and the location of ICAR institutes. Red rot and its fungus, the Coimbatore institute and the ‘Co’ nomenclature are likely material for statement questions.
2. Mains asks about cropping patterns and the sugar economy. Questions have covered the sugarcane pricing system, cane arrears, the water intensity of sugarcane and the ethanol programme. This story adds the dimension of genetic vulnerability and the need for a pipeline of new varieties.
3. Agricultural research and extension is a GS3 syllabus item. The syllabus mentions technology missions and e-technology in the aid of farmers. The slow path from breeding to identification, release and seed multiplication illustrates why good varieties take years to reach farmers.

Analysis

1. Co-0238 was a success that became a risk because nothing replaced it. Co-0238 raised both yields and sugar recovery and made UP India’s top sugar producer. The error was not in breeding it but in the absence of a varietal replacement plan. Mills encouraged farmers to plant it because it raised recovery, and farmers planted it because it paid. Nobody bore the cost of the rising risk until the CF13 pathotype appeared. The lesson is that variety diversity is a public good that neither mills nor individual farmers will provide unless the State plans for it.
2. Co-20016 should not become the next Co-0238. A variety with 24% higher yield and red-rot resistance will be planted widely and quickly. If it covers most of UP’s cane area, the same process can happen again, with a new pathotype able to infect it. The State should plan a spread across several varieties, including Co-21012 once its trials are complete, with a limit on any one variety’s share in disease-prone belts. Mills’ cane development departments, which supply seed to farmers, are the right place to enforce this.
3. Seed multiplication is the real bottleneck. Sugarcane is planted from setts, not seeds, and the multiplication rate is low. Even after the Central Varietal Release Committee approves Co-20016 in October, it will take several seasons to produce enough healthy seed cane. Tissue-culture plantlets and single-bud methods can speed this up. Distributing infected setts would carry red rot into the new variety’s fields, so certified disease-free seed is essential. Without a multiplication plan, the variety will help only a small share of the crop before the 2027 election and beyond.
4. The fall in UP’s cane affects farmers, mills and the ethanol programme. A fall of more than a fifth in cane crushed is lost income for farmers who were already paid at a fixed price per tonne, since lower yields mean fewer tonnes. Mills lose throughput while fixed costs stay, which can lead to delayed cane payments. Lower sugar output also leaves less cane juice and molasses for ethanol, putting pressure on blending targets and raising the question of food versus fuel. A crop-disease problem therefore becomes a question for rural incomes, State politics and energy policy.
5. Waterlogging and agronomy matter as much as genetics. Dr. Bakshi Ram points to waterlogged fields in central, eastern and Terai UP as the places where red rot spreads fastest. Resistant varieties buy time, but drainage, crop rotation, removal of infected clumps and hot-water treatment of setts reduce the pressure on resistance genes. An approach that relies only on a new variety will wear out that variety faster.

Administrator's brainstorm