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.
Timeline
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.
Future Improvement
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.
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.
Sustainable
Agriculture
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.