Plant Breeding: An Ingenious Human Innovation
Abdul Awal Mintoo
M.Sc in Agricultural Economics
Former President, FBCCI
Amid the growing world population, the shrinking arable land and global challenges like climate change, the need for resource-efficient farming systems are becoming absolutely vital to feed the booming population. This is possible only through innovations in plant breeding. The new plant varieties that can withstand the sudden excessive temperature, drought, flood, and salinity have become essential. The new plants should also be more tolerant or resistant to pest, disease, and other biotic and abiotic stresses. The new plants should be more productive and the yield should be stable, irrespective of climate and various stresses. Increased productivity means the use of fewer resources and inputs, such as land, water, pesticides, fertilizers or other nutrients.
Producing more foods with fewer resources by improving the agricultural productivity should, therefore, be the main focus of agricultural scientists, plant breeders, and policymakers. The UN Convention to Combat Desertification (UNCCD) insists that there is an urgent need to boost agricultural productivity to meet the present and future demands for food. The climate change is already making food insecurity worse, while global agriculture crop yield may diminish by 30% by 2050.
By 2050, the world population is expected to increase to 9.8 billion from the present 7.3 billion (2016), while the availability of arable land will decrease to 0.15 hectares from the existing 0.20 hectare per capita. The average global temperature is expected to rise to 16.0ºC from the current average of 14.7ºC. The demand for water will rise to 5,500 km3 from present 3,500 km3. Due to global warming, it is estimated that 20-25% of the crop will be lost to pests compared to the present loss of 10 - 15%. These are no longer any assumptions as those happening in reality.
Humans are in a critical juncture of history. Booming population, urbanization, desertification, degradation of land fertility, climate change and other environmental factors like the melting of Arctic ice and mountain glaciers, rising sea level and the changing pattern of various ecosystems at various places are threatening the food security in an unprecedented scale. Bangladesh will be one of the worst affected countries. So, improved varieties of food crops are the only way to reduce the risk of economic and climatic shocks for millions of people who are resource-poor and vulnerable.
Crop Improvement Various Methods
There is nothing new in crop improvement, as it has been taking place in various ways and manners for thousands of years, but it gained momentum in 1866 with the introduction of Mendel’s Law of Genetics. It even accentuated further from crossbreeding in the 1900s and the introduction of mutation breeding from the 1930s. With the new technologies of genome sequencing and elucidation of gene functions, it is now possible to introduce new breeding methods that help improve the selection process. By using genetic markers, breeders now can select specific genetic traits more efficiently and select useful traits that can be best combined in crossbreeding to develop a hybrid.
Plant breeding has a long history of innovation. Originally, the crop was improved through a selection process. By 10,000 BC, humans started improving crops like wheat. The timeline from history shows that by 5,000 BC human improved linseed, flak wheat, Barley; by 4000 BC Maize and Millets; by 3000 BC – Potatoes, by 2000 BC Rape seeds (oil seeds) and watermelon; by 1000 BC – Rye; and by 1950 AD they improved sugar beet. In 1866, Mendel established his “law of genetics”. Following the same principle, crossbreeding started in 1900; hybrid breeding in 1920; mutation breeding in 1930. Subsequently, agricultural scientists established tissue culture in 1960, gene transfer (GMO) In 1996, Marker-assisted breeding in 2000, and new technologies of genome sequencing in 2010, finally introduced the gene editing in Plant Breeding in 2013. However, the controversy surrounding the crops produced by gene editing are yet to be settled. The issue in question whether such crops are GMO (Genetically Modified Organism) or not.
From the above timeline of innovation, one can see that humanity has been vying to improve crop quality and productivity from the advent of the agricultural civilizations 12-13,000 years ago. However, since the introduction of laws of genetic by Mendel, plant breeders have developed many new breeding methods. These methods have increased genetic diversity and allowed the selection of best performing traits, and eventually the most efficient plants. The major goal of plant breeding is to continuously make the use of plant genetic diversity and simultaneously increase plant diversity.
Radiation was first used in the 1930s to induce random mutations in the plant’s genome, followed by an intense selection process to identify the valuable traits. Besides radiation, chemicals are also used for various crops to induce mutations and selection of most desirable traits. Recently, drought-tolerant wheat has been developed in Kenya using gamma radiation which increases yield significantly. These plants produce predominantly female flowers and set fruits without pollination.
Monoecious to Gynoecious
Cucumber; the varieties which are cultivated worldwide are of gynoecious variety. Gynoecious means the induction of female flowers and fruits at every node. Farmers and consumers, both prefer the gynoecious variety but Bangladesh lacks such variety. Agricultural Scientists and breeders at Lal Teer Seeds (LTS) have been looking for the gynoecious trait in cucumber. Generally, out of different growth-promoting hormone auxin plays a vital role to define flower sex of cucumber. High auxin concentration tends to promote ethylene synthesis which favours the development of female flowers. So, based on this physiological information, breeders at LTS trying to stop the ethylene signaling pathway to induce male flower instead of female. They use silver ion chemicals to induce male flowers on gynoecious plants to maintain this noble trait. However, it is difficult to induce male on time for pollination and maintain pollen sterility.
To overcome this shortfall, breeders using chemicals for mutation and TILLING to develop gynoecious line of cucumber. TILLING (Targeting induced Local Lesions in Genomes) is a method in molecular biology that allows the identification of a mutation in a specific gene. In this process, seeds are treated with EMS (Ethyl Methane Sulfonate), a mutagenic chemical and a large mutant population is generated. Then DNA is extracted and subjected to mutation screening in genes controlling flower sex determination. There are five genes involved in sex determination of cucumber. Out of these five genes, if the monoecious gene CsACS2 is altered by a mutation on the TILLING platform, there might be a chance to transition the monoecious flowering character to gynoecious. Finally, backcrossing with the base population creates a reverse sex type monoecy to gynoecy as a result of reverse genetics. Besides the mutant gene can be used in a hybridization program of cucumber in which the mutant gene can be incorporated into the genome of the preferred variety by cross-breeding. This is the way the newly found trait is transferred to the new variety.
Past and Present
Major genetic mutations and modifications were made in the past by plant breeders. One such modification that has fueled past agricultural revolution was “turning the plants flowering signal to increase yield and developing hybrid plants, which can tolerate different climate, enhance growth and resist diseases. In the early days, beneficial development like these was discovered by chance. Modern genomics has revealed that most of these are rooted in two core hormonal systems; Florigen, which controls flowering; and Gibberellin, which influences stem height. Recently available biotechnological tools like gene editing (CRISPR-Cas 9) can be applied to change the core system within the wide varieties of plants and do not have to wait to be discovered by chance.
Many of today’s innovations are the results of both continuous innovations, improvement and disruptive innovations. It is the human insecurity that drives scientific advances to improve the quality of life. One such situation is knocking at the door. Thus, the immediate strategy should be to improve agricultural productivity. Such strategy must be based on innovations of plants that enable farmers to face challenges such as limited land, diseases, and climate change. This will help farmers grow enough food to feed the growing population.
One recent example is the improvement in cotton plants by dwarfing the plants in China. Chinese scientists have transformed the normally sprawling cotton plant, usually ideal for southern China, into a more compact bush type, faster growing and early flowering. Such plants are better suited for China’s northern climatic regions. This dwarfing system was also applied to Rice Plants to avoid storm damage. The replication of the same techniques to different plants to achieve the same results push us to think that the “core system of wide varieties of plants function in the same manner”, even though these plants are very different in terms of their phylogeny. In another way, we can think that despite the phylogenic difference in a plant, they function in the same way; from making leaves to making flowers. To make such changes in the plants, scientists took the advantage of a mutation that affects florigen, the process which promotes flowering, and its opposite, anti florigen.
Tinkering in the Core System
If in the core system of the plants, Gibberellin, Florigen or both are affected by the mutation, then it may result in one or more noble traits. After planting such mutated seeds, breeders identify such new traits. Then it takes many years of breeding or one may even say that “tinkering of one trait with another” until finally it is best tuned to produce a right plant with the right traits, which are acceptable to farmers and consumers.
To overcome future challenges, breeders will have to develop improved plant varieties which are; (a) Resistant to pests and diseases or can be treated for diseases with fewer inputs; (b)Tolerant of biotic-abiotic stresses; (c) Increase yields despite the impact of climate change; (d) More yield with minimum resources; like land, water, nutrients; (e) and products shall meet the farmers and consumers preferences.
In Bangladesh, for example, onions are usually planted in early November. This year (2019), much of the land in the onion growing area remained inundated (November end) due to rain during October. As a result, planting in many areas is delayed until December. Late planting means late harvesting – April. By that time early rains will set in. Thus, farmers may have to harvest early, just like in 2018. Early harvest will reduce the yield and water contents will be high. That will reduce the storability. If the onion price remains high then farmers may even harvest early to encash the profit, before one bulb is fully grown to its potential. Such a situation may increase the possibility of a shortage of onion in the market during late 2020.
In the case of Bangladesh, apart from the yield, three other traits are very important; storability, pungency and low water contents. Modern breeding tools and techniques opened the door of possibility to improve plants to tolerate such climate conditions like shortening the harvesting period to avoid early rains. It also has the ability to increase or decrease pungency. Such issues are not unique to onions but for many other crops. Take the example of Papaya. Consumers prefer red flash and more sweetness. Present Bangladeshi varieties lack both of these traits. Modern breeding techniques can improve these two traits.
Evolution Versus Inducement
The improvement of crop variety has been taking place through the evolutionary process of mutation from the beginning of the agricultural age about 10,000 – 13,000 years ago. The process is accentuated since the discovery of Mendel’s Law of Genetics, and further accelerated from the early 20th century with the introduction of cross-breeding. Now the mutation breeding and tissue culture techniques combined with the new technologies of genome sequencing and elucidation of gene functions. Created new tools and new opportunities. New tools will help accelerate the selection process of new varieties by assigning genetic markers to specific traits more efficiently. By genetical fingerprinting, plant breeders can select plants with the best traits and then combine other noble traits through cross-breeding for better hybrids, which can yield more with fewer resources.
Though mutation is an evolutionary process, it can also be induced by radiation and chemicals. The mutation affects the core system either – Gibberellins and florigen or both. The mutation may result in some noble traits (sometimes not) which are very helpful. The mutated genes of good traits can be identified by breeders in the plant. It then takes many years of experiments by plant breeders to figure out the usefulness of the new traits and determine the level of its quality. It is most likely that in the future by using the New Molecular tools like gene editing, scientist may create more and more novel diversity in the two hormone systems of plants which will unleash the new agricultural revolutions. One of the key moments in agricultural history is the Green Revolution, and now the world desperately needs one more agricultural revolution.
New Tools of Breeding
New Molecular tools of precisian breeding will help plant breeders do their job in a precise manner more efficiently compared to the past. New tools like CRISPR – Cas-9 mechanisms -- do not only randomly increase the genetic variations, as it is done by radiation or chemical mutagenesis, but also precisely introduce mutations in genes of known functions. They are now able to either impair the particular gene functions by deleting or by improving their functions. These precision breeding tools can create plants that might also have been produced by conventional breeding methods like chemical or radiation mutagenesis. However, these plants cannot be distinguished from one another with respect to breeding methods that have been used to create these plants. The only difference lies in the efficiency of the process and the efficiency of the plants, in terms of particular traits and yield.
New Molecular tools, known as precision breeding, can help improve specific traits but they need to be integrated in the desirable agro-economic characters, in terms of preferences of consumers and the requirement of farmers.
For example, a plant that possesses the noble traits of disease or pest resistance but having very low yield is of no value to the farmers, or an onion variety of high yield but not pungent and contains high water contents or less storability will not be a preferable variety to Bangladeshi consumers and/or farmers. As the growing population and climate change endangering food security, scientists around the world are working to overcome the challenges that threaten the dietary needs of not only human but also of livestock.
Time and Cost to Develop New Variety
The Seed Industry works with plant breeders to create added value by developing new varieties of crops. Each new variety takes 8 to 11 years to develop, depending on the breeding methods. The cost to develop each new variety is difficult to determine but some estimates that in The United States the cost of developing some widely cultivated high-value crops variety may even exceed US$100 million, like corn or Soybean. As the cost of developing a new variety is very high, seed companies usually tend to invest in crops that are widely cultivated to recover the investment made in R&D as soon as possible. However, the new molecular tools can reduce the time and cost both to develop new varieties.
Employment in Agriculture and Poverty Reduction
For Bangladesh, increasing agricultural productivity is undoubtedly the most fundamental importance right now because 45% of the working-age population is still directly employed in agriculture while another 15% in the non-farm sector which depends on the agricultural sector. Boosting agricultural productivity is, therefore, the surest way to enhance their livelihood and lift millions of people out of poverty. This is especially true given how difficult it is to create and sustain the non-farm jobs for people to move to.
In the past, increased agricultural productivity in Bangladesh pulled many out of poverty, but significant poverty still remains. Recent reports show that the rate of poverty reduction has slowed down. What is even more worrisome is that even though agricultural productivity has gone up across the world. Poverty reduction is slowed down and undernourishment is on the rise in many developing countries.
Apart from the climate change in general, the most daunting challenges to agriculture are issues like a flood, drought, extreme heat, sudden excessive rains, flash floods, riverbank erosion, shrinking arable land, degradation of land fertility, and rise in salinity in particular, is to be addressed in the near future. FAO estimates that a 3–5% decline in average global cereal yields for every 1ºC increase in temperature. This is applicable in general to every place and everywhere, but for Bangladesh, the added problems are degradation of land fertility and shrinking arable land due to urbanization, industrialization and riverbank erosion. Slow agricultural productivity along with above-added problems, it is nowhere more important than for Bangladesh. In fact, time is running out for tackling extreme poverty.
Land Reform for Agricultural Productivity
Some view that rising landless population, the pattern of marginal landholding, smallholder farming, climate change, lack of knowledge of modern cultivation methods, are serious impediments to improving agricultural productivity. Therefore, land reform is necessary to transform farming from smallholders to large scale commercial farming. Many others say that the very nature of social structure and religion, any gain from any kind of land reform or reallocation of land and labour in favour of larger holding to increase productivity is almost non-existent. Land reform is not the issue of today’s writing. Such issues are always controversial anyway. Either way, availability new scientific tools available to scientists and breeders, the productivity in agriculture can come from better agricultural inputs like seeds, which has better yield and traits of consumer preferences and farmers acceptance, and able to withstand the effects of climate change. This is achievable only by investment in agricultural R&D.
Investment in agricultural R&D can generate and disseminate better inputs and sharper agricultural knowledge. The rate of return for R&D in agriculture is nearly 30-40% higher than many alternative investments. R&D investment, as a share of agri-GDP, is six times higher in developed nations compared to developing
ones, while the number of R&D workers is 50 times higher. Unless Bangladesh increases investment and focuses on agri-R&D, apart from correcting its many agri-policy flaws, lifting the next many millions of its poor out of poverty will be much harder than before. In fact, the present economic and social indicators combined with political instability, proves beyond any doubt that the stage is set for poverty to rise, rather than a reduction in the future.
Therefore, the government must adapt consistent, science-based policies for plant breeding and agricultural innovations, to help achieve adequate food production and supply, not only for rice but also for all food crops. This will ensure consistent farmers income, faster reduction in poverty, improvement in nutrition of a growing population, and sustainable use of natural resources. Production of more food crops with less resources and in a sustainable way should be a fundamental concern for Bangladesh today. We must recognize that contributions of science and innovation are the way to enhance agricultural productivity, improve food security, better nutrition for all, improve farmers’ livelihood, reduction in poverty and adapting to climate change. For any endeavor towards increasing agricultural productivity, the seed sector is the starting point of the food production and supply system. The seed sector is at the forefront to act as the main actor and can offer science-based solutions to address these challenges. The seed industry is unique because of its primary role in crop production. Providing quality seeds is the critical first step towards solving many challenges. It focuses on the five pillars simultaneously. These include; breeding to develop new varieties with better traits, quality seed production, processing and treatment, storage and delivery to farmers (Marketing) and extension services.
Investment in R&D
The seed sector is supposed to invest at least 15% of its turnover in R&D each year. This can ensure the development of quality seeds of improved varieties that are locally adaptable and accessible to farmers. This requires government support. Unfortunately, such a supportive policy to assist the seed sector is virtually non-existent. It has, therefore, become an urgent issue to adopt consistent, science-based policies to support the sector for sustainable agriculture, or else, the nation will miss out on the potentials. At this point in time, the regulatory environment, tax system, and government policy do not favor the private sector in plant breeding. This will inevitably slow down the delivery of better inputs to farmers in the near future. In order to tackle many challenges being faced by the agricultural sector including mitigation of effects of climate change and food security, innovation by plant breeders is essential. No matter who says or thinks what, it is for sure that the present strategy and government policy are obsolete for any kind of innovation through research. Therefore, there is a need to build understanding and trust among all stakeholders, to develop quality seeds and other inputs. All these should be easily accessible to farmers. Otherwise, farmers will not have the full range of choices and solutions to achieve sustainable food production.
Seed or Sector and Implementation of SDG
The 193 Member States of the United Nations have adopted the Sustainable Development Goals (SDGs) in September 2015 which are the priorities for the world up to 2030. There are 17 SDGs in total. Improving the productivity of smallholder farmers are one of the main targets. Smallholder farmers need to not only produce more food but also at the same time adapt their agricultural practices to changing weather conditions caused by climate change. By improving access to quality seeds, seed companies can make a vital contribution by supporting smallholder farmers by overcoming this challenge.
Bangladesh’s seed sector is fully aligned with Sustainable Development Goals (SDGs). Of the 17 SDGs adopted by the United Nations, the seed sector contributes to or aligned to a majority of these goals; such as No Poverty; Zero hunger; Good health and wellbeing, decent work and economic growth; Industry, innovation, responsible consumption and production; climate action for better life and partnership. In one way or the other, agricultural activity, productivity, and productions are tied up in achieving these goals.
Remarkable innovations are needed so that farmers can grow enough food (not only rice) for the growing population of Bangladesh, while preserving natural resources for the next generation. We must ensure that our future generation will not suffer because of our action or non-action today. The present generation, like all previous ones, bear the responsibility for the wellbeing of future generations.
In the future, educated consumers will demand a better and healthy diet with no negative impact on their health and environment. New agricultural innovation should improve the livelihood of smallholder farmers in Bangladesh by providing more access to sustainable agriculture practices and solutions because they are the majority in society. Investment for tomorrow’s breakthroughs will require collaboration and engagement with scientists, innovators, regulators, farmers, and consumers (all stakeholders) to build trust, confidence and societal acceptance.
Dominance of Public Sector
Until recently, most developing countries had agricultural sectors totally dominated by the public sector with extensive oversight. State controls often included research, production, marketing, input supply like fertilizer, financial credit (through publicly-owned banks), and extension services. In the past decades, there is, however, a growing understanding that public sector dominated agriculture is not sustainable because of budget constraints, mismanagement, politicization of research institutions and lack of innovation. As population continues to grow, the present system is inadequate and unable to deliver innovation for agricultural productivity anywhere near the level of requirements. To meet the future demand, the approaches to agricultural research, production, productivity and extension services should be more pluralistic. In fact, many agricultural services including research, the supply of inputs and extension services can be delivered more efficiently and effectively by the private sector.
Collaboration with Private Sector
Major impediments in agricultural productivity in Bangladesh include the non-availability of quality inputs like seeds and extension services. For example, the productivity of onion per acre in India is about 7 tons while in Pakistan 6 tons and in Bangladesh it is only 3.66 tons per acre. Onions are cultivated in five hundred thousand acres of land and producing about 18 lakh tons with 3.66 tons per acre. The total demand for onion in Bangladesh is about 30 lakh tons. If productivity can be raised to 6 or 7 tons per acre, then the cultivated land could produce 30 to 35 lakh tons. This means the country can be self-sufficient with onion and would not have to import. Private agro-input retailers are uniquely positioned to address these challenges and support farmers. The success of the input suppliers is directly related and connected to the success of their customers – farmers.Market actors like input retailers need to possess skills and knowledge to enable them to transfer to farmers. In fact, some small retailers possess real good skills how to adulterate seeds which immensely causes damage to farmers, instead of enriching the knowledge of agriculture. For agro-input retailers, the challenges include the lack of business acumen, modern cultivation agricultural technical knowledge, access to finance and lack of implementation of regulations against adulterators by the government. There must be a diagnostic tool to help them acquire such knowledge. Improving the professionalism of agro-input retailers will help direct the farmers through product advice and dissemination of new technologies and agricultural practices. The government, therefore, must change the policy of business towards the public sector, instead must adopt the policy of collaboration with the private sector.