Once hailed as the saviour of billions of hungry Indians, the semi-dwarf High Yielding Rice varieties ( HYV) are now here, and they are being denounced as a harbinger of destruction. People antagonistic to HYV rice argue that the proliferation of these contemporary rice varieties extensively throughout the nation poses a detriment to the artistry and essence of traditional rice cultivation. To these critics, modern varieties are perceived as the merciless slayers of heirloom rice diversity, jeopardising the natural resilience against pests and diseases, and accelerating the degradation of soil and the environment. Questions have even been raised about their potential and achievements. So, the celebrated yield superiority of HYVs over traditional rice is being claimed by Ashraf and Lokanadan in the International Journal of Current Microbiological Applied Science 2017 as just a story and propaganda by the state agricultural scientists and extension staff to promote its cultivation. Is it not imperative to thoroughly investigate the rationality of the allegations before relentlessly accusing a friend in times of distress?

The birth and diversity of domestic rice

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Currently, the paddy we cultivate, and the rice we eat, had no existence at all in nature. Nearly seven thousand years before Jesus’ birth in Jerusalem, Asian cultivated rice emerged from the ancestral womb of wild rice, Oryza rufipogon revealed by Molina and his co-researchers in the Proceedings of National Academy of Science 2011. Such a profound evolution from a wild, weedy perennial to a cultivated, annual rice with upright stems and strongly bound rice was guided by the natural mutation of four pivotal genes (SH4, QSH1, Prog1 locus and RC) of a wild ancestor and the discerning selection pressure of ancient farmers unearthed by E, Callaway, 2014. This transition didn’t happen overnight. Instead, it’s been slowly unfolding across a thousand years, showcasing the enduring partnership between humans and nature. As nature meticulously sculpted the wild form of rice, yielding a myriad of variants genetically tuned for survival and proliferation in diverse environments, ancient farmers embarked on a quest, handpicking superior yield, tantalising taste and fortitude against pests and diseases. Survival of natural rice variants thus depended solely on the preferences of our farming ancestors. Unless the variants align with farmers’ choices, they are supposed to fade away over time. It is therefore evident that since the inception of rice cultivation, the fields have been gradually losing the rice varieties disliked by farmers. HYV rice came into existence many millennia later.

Archaeological records referred by Durai and co-workers in the Indian Journal of Plant Genetic Resources 2015 indicate that in the Indian sub-continent, the cultivation of Asian rice originated in the Ganges valley of the northeast in 6500 BC. The genetic modification of rufipogon boosted the adaptability of Asian rice to such an extent that its cultivation spread rapidly across the country, much like a blazing wildfire in no time. From the arid, desolate soils to the rich fertile plains, the story of rice cultivation unfolds. It spans the rugged terrains of the Himalayan foothills, descending the icy heights to the warm, briny marshes or the untamed, green lowlands below. Such is the vast expanse of its reach. According to eminent rice scientist TT Chang (1989), domesticated rice varieties exhibit the greatest diversity within the geographic belt stretching from North East India to South East China. With India particularly West Bengal nestled within this belt, it’s no surprise that these regions showcase a lush tapestry of rice diversity.

The exact count of rice varieties is a mystery, but their multitude of names and uses hints at the vastness of biodiversity. Renowned rice scientists R. H. Richaria, along with Govindaswamy claimed in their book Rice in India that India once cultivated  2,00,000 varieties of rice. In contrast, experts like Paroda and Mallick, as well as organisations like IGMORIS, estimated the number of traditional rice varieties in India to be 50,000. In 1955, scientists led by S. Gobindaswami began India’s first exploration of rice biodiversity, collecting 1,745 indigenous rice varieties through extensive search over a period of five years ( 1955-59) in 27,000 square kilometres area of the Jaipur region, now known as Koraput district. In a separate effort from 1967 to 1972 M.S.Swaminathan and S.V.S.Shastri collected 6,000 indigenous rice lines in Northeast India, known as Assam Rice Collection. R.H.Richaria also made substantial contributions between 1970 and 1979. He collected 19,226 local rice varieties, known as the Raipur Collection, from 42 districts of Madhya Pradesh. Again in 1971, under the initiative of IARI, Hyderabad, Sharma and his fellow scientists gathered altogether 8,000 local rice from the hilly areas of Meghalaya, Arunachal Pradesh and Assam in the first phase and Manipur, Tripura and Mizo Hills in the second phase. Various states also joined this venture in the 1950s. Accordingly, the total number of indigenous rice varieties collected at both the state and national level and accessed at NBPGR(National Bureau of Plant Genetic Resources) reached 66,000 up to 1982. Out of which 50 per cent were the same rice varieties with different Accession numbers. In fact, the collection of local rice in NBPGR stood at 36,000 up to 1982 noted by Hore and Sharma in the Indian Journal of Forestry, 1991. Currently, the NBPGR has a rich collection of 1,04,538 rice Accessions.

Let’s also look at the post-independence West Bengal’s rice biodiversity. Estimates vary, with Pal listing 5000 varieties in News Research, 2016 and Deb identifying 15000 in Gastronomica, 2021. Notably in the 1970s BRRI scientists reported the existence of 12,479 indigenous rice varieties in Bangladesh. In West Bengal, the Chinsurah Rice Research Station began collecting indigenous rice varieties in the mid-1950s, eventually amassing 5000 indigenous varieties.

The dawn of high-yielding rice on the Indian canvas 

In 1947, when the British left India, the country’s food situation was extremely dire, exacerbated by the partition, which took away our key wheat and rice-growing areas. By 1950, the population had reached 361.1 million, but the domestic food production of 50.82 million tonnes was insufficient to meet the basic needs. The global post-war recovery further limited import options. Despite an agreement with the USA to import 10.6 million tonnes of food grains between 1956-1959 and subsequent renewals for even larger quantities, these imports drained India’s exchequer and failed to resolve the food crisis. Up to the mid-1960s, the Indian efforts to increase food production concentrating largely on expanding farming areas with improved local varieties did not yield significant results. Faced with a persistent food shortage, India recoursed to increasing the yield of the country’s two principal food crops, rice and wheat. At this pivotal moment, news broke of a groundbreaking development in the field of IRRI: the long-waited rice variety, IR8, had finally come to fruition. This extraordinary variety had been a vision of the experts from the International Rice Commission as far back as 1949. IR8 in semidwarf stature and 130 days maturity duration promised astonishing yield, producing 10 tons per hectare with 120 kg nitrogen fertiliser and 5 tons without any nitrogen input. At the helm of IARI, the visionary Dr Swaminathan recognised the immense potential of IR8. His unwavering advocacy, coupled with the endorsement of the then Minister of Agriculture, led the Central Variety Release Committee to make a historic decision to release the variety across the country in 1966.

In 1967, the evolutionary adoption of semi-dwarf HYV rice began in the remote village of Atchanta in the west Godavari district of Andhra Pradesh. It was spearheaded by a 29-year-old progressive farmer, N. Subbarao. When the new IR8 rice variety was cultivated across a vast area of Subbarao’s land, it yielded astonishing results. Curious villagers flocked to witness this miracle. They observed in awe, as this short-duration, hardy newcomer produced a yield three times higher than the traditional varieties they were accustomed to. Dreams of a golden future filled their eyes. The entire harvest from Subbarao’s field was used as seed for the following year, leading to the cultivation of IR8 rice on 1600 hectares within the same village. The wave soon spread throughout Andhra Pradesh, then to Tamil Nadu, Karnataka, and Hyderabad, and eventually across the entire country. Hot on the heels of IR8 came other varieties like Jaya, Padma etc. As these HYV rice varieties spread like wildfire, they began to transform the landscape of rice production in India. In 1950, rice production stood at 20.8 million tons from 30.8 million hectares. By 1969-70, this had surged to 40.8 million tons, without significant expansion of the rice area. The key to this revolutionary increase was the tripling of yield rates. Within three decades of introducing HYV rice, India not only became self-sufficient in rice production but also started amassing a buffer stock of 15.7 million tons annually. From being a traditional importer of rice, the country thus transformed into a self-reliant producer, banking on semi-dwarf HYVs.

Some have historically contested these facts, claiming that the high yield potentiality of these varieties was exaggerated by government officials and the farmers were coerced into cultivating them. Opponents of HYV further argue that these varieties are hybrids, created by crossing indica and japonica strains, with japonica being particularly susceptible to pests and diseases. They allege that these have led to widespread pest and disease problems across the country, while traditional varieties supposedly remain unaffected. However, none of these assertions are true. These varieties are neither hybrids nor the result of indica-japonica crossbreeding. Like any other traditional varieties, they are all inbred.

IR8 is actually a semi-dwarf derivative resulting from Indonesia’s high-yielding tall indica variety, Peta, and Taiwan’s dwarf indica variety, Dee-geo-woo-gen. The magic behind this semi-dwarf variety and its high yield lies in a gene named sd-1. This gene is located on chromosome number one of the Dee-geo-woo-gen variety. Its function is to reduce the synthesis of the gibberellin growth hormone (GA 20 oxidase) in rice cells. As a result, the internodal regions of the rice stem become shorter, making the plant dwarf and sturdier. This structural change means that even with heavy grain heads, the plant does not topple over. This modification significantly alters the plant’s physiology. The sd-1 gene not only prevents unnecessary elongation of the plant by reducing the expenditure of produced dry matter but also efficiently redirects this conserved dry matter to increase grain production and yield. That’s the extent of the sd-1 gene’s role – it’s the key to the dramatic yield increase. In terms of biomass production, there’s not much difference between HYV rice and traditional varieties. However, the yield difference is enormous, making all the difference in productivity. A 2020 study by Panth also highlighted that farmers gain much higher profits from cultivating HYV rice compared to traditional varieties, primarily because the yield is three times greater. Critics often downplay this yield potential by attributing it to the use of fertilisers and irrigation. However, just as the sun is the ultimate source of energy in the universe, the seed is the core source of all agricultural potential. Other agricultural inputs merely assist in unlocking the inherent yield potential of the seed. If fertiliser usage contaminates the soil, why blame the seed? Moreover, the claim that the native varieties are always disease- and pest-resistant is also untrue. If it were true, the yield of rice in Bengal wouldn’t have plummeted due to the brown spot disease in 1942. On the contrary, most of the currently popular HYVs are tolerant to multiple pests and diseases. The propaganda against HYV rice ignores these facts and tries to paint a misleading picture.

A look at the disappearance of heirloom rice 

The loss of diversity in rice began long before the advent of HYV rice. In fact, it started from the very beginning of the domestication of rice. Whenever a superior variant of rice has emerged, farmers have readily moved away from cultivating the inferior ones in favour of the better variant. It happened during the process of domestication and also afterwards. The replacement of one variety of indigenous rice with another more productive variety by farmers reflects their keen desire for higher yield. This is only natural. Agriculture is their livelihood. If the crops produced in the field are consumed entirely at home, how will he go to the market to sell them? How will his household run? The more rice a farmer can produce beyond his household needs from his own land, the more comfortable his life will be. This pursuit of better yields has driven farmers since ancient times and continues to do so today. When the initially used indigenous was found low-yielding, it was replaced with improved indigenous rice varieties, and subsequently, HYV rice was introduced. The rapid adoption of HYV rice, replacing traditional varieties was driven primarily by the promise of harvesting more rice and endorsed higher income for the farmers. The research findings published in the Journal of Agriculture and Environment in 2020 corroborate this fact.

Although the promotion of HYV rice varieties has largely edged out traditional varieties from the fields, they have not vanished entirely. These cherished heirloom strains still flourish in specific ecological niches where HYV rice fails to prevail. Their survival is owed to their superior taste and aroma, or their remarkable resilience to fragile environments. The next phase involves the delicate extraction of these resilient traits from traditional varieties into HYV rice, enhancing its qualities. Successes such as Swarna sub1, Jarava etc. bear testament to these efforts. As this endeavour progresses, the cultivation of traditional rice will gradually diminish, surviving in pockets only as commercially viable varieties. This seems an inevitable trajectory. However, even if they fade from the fields, they will not be lost forever. They will be meticulously conserved in repositories like NBPGR and IBPGR, safeguarding their legacy and essence for the generations to come.

Those advocating for the widespread cultivation of traditional rice over HYV rice should consider India’s 107th position out of 120 countries in the Global Hunger Index 2022. The same year’s Global Food Policy Report forewarns that by 2030, India will host the largest number of hungry people in the world, totalling 17 million. According to FAO, despite the continuous rise in annual rice production and yield in India over the past three decades – registering a 2.4 per cent increase in production and a 1.9 per cent increase in yield – the growth is still insufficient to meet escalating demand. To eradicate hunger and achieve self-sufficiency in rice production in the coming days, we must not only rely on HYV rice but also develop and adopt even more advanced, ultra-high-yielding rice varieties that surpass the yield limits of HYV strains.

Subhendu Deb Chatterjee is former director &  ex-officio secretary of, the Department of Agriculture, Government of West Bengal

Amitabh Ghosh is a former economic botanist IX, Department of Agriculture, Government of West Bengal