Chapter 3. Agriculture and forestryClimate-resilient plants Plants must increasingly adapt to salinity, drought, floods and other climate-related impacts. From conventional breeding techniques to CRISPR technology for genetically-modified crops, technology can help increase plant tolerance to such stressors. Meanwhile, integrated farming systems like agroforestry are gaining recognition as a means of strengthening crop resiliency and responding to food security threats.
Plants must increasingly adapt to salinity, drought, floods and other climate-related impacts. From conventional breeding techniques to CRISPR technology for genetically-modified crops, technology can help increase plant tolerance to such stressors. Meanwhile, integrated farming systems like agroforestry are gaining recognition as a means of strengthening crop resiliency and responding to food security threats.
Innovation examples
Seawater rice in China
Rising sea levels lead to salt-water intrusion in groundwater and increased soil salinity. This makes it difficult for crops to survive. Salinity… Read more
Rising sea levels lead to salt-water intrusion in groundwater and increased soil salinity. This makes it difficult for crops to survive. Salinity is exacerbated by groundwater depletion driven by droughts and a stronger demand for irrigation. Soils in China are severely affected by this problem.[1] About 100 million hectares of land in China equivalent to the size of Egypt is high in salinity.[2] Farmers traditionally dilute the level of salt in soil by applying large amounts of freshwater. This approach is expensive and wastes water for limited yield improvements. Renowned Chinese agronomist Yuan Longping – dubbed the “father of hybrid rice” – has focused his research on rice since the 1960s. His team eventually made a breakthrough in developing salt-tolerant hybrid rice varieties through advances in traditional breeding techniques; namely, by over-expressing a gene from chosen wild rice more tolerant to salinity. After a series of experiments along coastal areas in China, the hybrids demonstrated high yields of up to 7.5 tons per ha.[3] In 2020, the Qingdao Saline-Alkali Tolerant Rice Research and Development Center launched an ambitious program of planting the hybrid rice in saline-alkali soils in three cities in Shandong and seven other bases across the country. In 2021, the group was provided with 400,000 hectares of land to expand production of the seawater rice commercially.[4]
Genetically-modified insect-resistant Bt-cotton was formally released in India in 2002. Genes from the soil bacteria Bacillus thuringiensis were… Read more
Genetically-modified insect-resistant Bt-cotton was formally released in India in 2002. Genes from the soil bacteria Bacillus thuringiensis were inserted into the cotton genome to render it toxic to certain insects. This cotton variety is effective at controlling cotton pests, notably common larvae feeding on the cotton fruiting body. Adoption of the Bt-cotton variety has been hugely successful. However, the impact of this GM crop has been controversial. There have even been reports of resistance in some pests, leading to massive breakouts.[1] However, within four years of its introduction, insecticide use on cotton halved and average profits approximately doubled. Five years later and 6.8 million farmers planted 9.4 million ha of Bt-cotton hybrids. Bt-cotton has made India a net exporter of cotton for the first time. For five consecutive years after 2005 India produced over 5.1 million tons of cotton, up from 3 million tons annually before its introduction. The seed quality control introduced with the new hybrids was a major factor in their success. There are now some 780 Bt-cotton varieties with several different genetic traits available from more than 30 companies. Competition and regulation has reduced seed prices from an initially very expensive 1,350 Indian Rupee (INR) (USD 17) for a 450 gram packet to nearly half that price. Moreover, increased profitability has enabled investments into other technologies including better pesticides and weeding implements.[2]
Push-pull technology is a novel approach in pest management that was developed by Kenya’s International Centre of Insect Physiology and Ecology (ICIPE) and Britain’s Rothamsted Research in collaboration with partners in Eastern Africa. The approach entails intercropping plant varieties that repel insects together with crops that trap them. In this case, the fodder legume silverleaf desmodium (Desmodium uncinatum) was planted together with maize, Napier and Sudan grass. Aromas produced by the desmodium repel (push) pests like the maize stemborer while scents produced by the grasses attract (pull) the stemborer moths so that they lay eggs in the grass instead of in the maize. Once hatched, the larvae are trapped in a gummy substance produced by the Napier grass which hampers their survival rate. Desmodium roots produce chemicals that stimulate germination of Striga seeds (a major parasite plant also known as Witchweed), but then prevent them from attaching successfully to maize roots. The weed eventually dies and the number of seeds in the soil is also reduced. In addition to enabling this push-pull effect to protect the maize, silverleaf desmodium and the grass both provide quality fodder for livestock. Desmodium also provides good ground cover and fixates nitrogen that improves soil fertility. Finally, biodiversity is improved through the intercropping of multiple species (Khan et al., 2008).
Selecting typhoon-resistant crops: Cassava and sweet potato
Growing cassava and sweet potato in the Philippines was found to substantially increase farmers’ climate resilience to extreme weather events… Read more
Growing cassava and sweet potato in the Philippines was found to substantially increase farmers’ climate resilience to extreme weather events such as typhoons. During the super-typhoon Ompong (also known as Mangkhut internationally), which wreaked havoc in the north of the Philippines in 2018, below ground crops such as cassava and sweet potato sustained only limited damage compared to other crops like banana and maize. As a consequence, farmers have started planting root and tuber crops strategically. Cassava has the benefit of providing long-term food security in the face of variable climatic conditions, by being able to be stored in the ground for up to two to three years. The use of tubers as security against extreme weather events is a measure that can be taken in any area where such crops can be grown. The Consultative Group on International Agricultural Research (CGIAR) is an umbrella organization for several public agricultural research institutes.
Marker-assisted breeding of climate-resilient rice
The International Rice Research Institute (IRRI, a CGIAR member organization) is using a technology known as marker-assisted breeding (molecular… Read more
The International Rice Research Institute (IRRI, a CGIAR member organization) is using a technology known as marker-assisted breeding (molecular breeding) to develop rice varieties that can withstand drought, flooding, heat, cold and soil salinity. The method provides greater accuracy and speed compared to traditional breeding methods, but without the addition of foreign genetic material into organisms. Examples of drought-tolerant rice varieties that have been developed, released and planted by farmers include Sahbhagi Dhan in India, Sahod Ulan in the Philippines and Sukha Dhan in Nepal. The average yield increase of these varieties is 0.8 to 1.2 tons per ha under drought conditions. Plant breeders have also developed flood-resistant rice through the discovery and isolation of the SUB1 gene that survive being submerged under water for up to 14 days, resulting in a yield increase of 1 to 3 tons for a 10–15 day flood.
Polytunnels for extended growing seasons and crop protection
Haygrove supplies polytunnels, greenhouses, substrate systems and associated technologies to growers of over 30 crops in more than 50 countries… Read more
Haygrove supplies polytunnels, greenhouses, substrate systems and associated technologies to growers of over 30 crops in more than 50 countries worldwide. The products respond to climate change challenges and protect sensitive crops against weather-related impacts. Polytunnels range from easily constructed, small-scale tunnels for subsistence farmers to multi-base structures with mechanical venting and climate control, measuring up to 5 meters in height. The large air volume in the bigger polytunnels means a slower rate of fluctuation in temperature. The tunnel fabric diffuses light and provides a thermal heat barrier that creates a more stable, stress-reduced growing environment for plants. Haygrove also provides double-skin tunnels. These can be up to 40 percent more efficient at retaining heat compared to a standard glasshouse without thermal screens.
Agroforestry and integrated farming systems for increased resilience
Agroforestry can increase the resilience of farmlands and landscapes to climatic stress. It does this by integrating trees with crops and/or… Read more
Agroforestry can increase the resilience of farmlands and landscapes to climatic stress. It does this by integrating trees with crops and/or animals to provide a range of agricultural and forestry products. Agroforestry systems can produce timber and other tree products, as well as food, fodder, fuel and shelter, while protecting ecosystem services provided by the natural environment. Agroforestry can also restore degraded forests and minimize the likelihood of erosion in sloping areas. The Regreening Africa project, led by ICRAF and supported by the European Union, is restoring over one million hectares of degraded land using agroforestry systems and practices in eight Sub-Saharan countries. ICRAF’s “Practitioner’s field guide: agroforestry for climate resilience” provides a set of technical instructions and tools for assisting farmers to design, establish and manage climate-resilient agroforestry practices. ICRAF is a CGIAR member organization.
According to the FAO, diversification of crop varieties is a way to hedge against risk of individual crop failure.[1] Before modern agriculture’s practice of monocropping became widespread, intercropping was a common method offering a sustainable means of growing different crop species together. Under the right conditions, traditional intercropping outperforms modern systems in terms of yield. Legume–cereal intercropping generally outperforms monocrop approaches, as legumes provide additional nitrogen and phosphorus to the cereal crop. Intercropping is gaining attention once again as a climate-resilient and sustainable farming method.[2] Intercropping can be used in mechanized farming, and in the United States strip-cropping is popular where wheat, corn and soybeans are grown alternately, six rows each. Covers & Co. is a cover crop and forage seed supplier specializing in diversified farming practices that improve soil resilience and lower input costs through methods like relay cropping and intercropping.
Sepaisa’s bioinsecticides are botanical and microbiological in origin. They offer a natural alternative to conventional synthetic insecticides… Read more
Sepaisa’s bioinsecticides are botanical and microbiological in origin. They offer a natural alternative to conventional synthetic insecticides for use in integrated pest management strategies and organic production systems. Pirecris® is one such bioinsecticide for pest control in crops, particularly for use against aphids, whiteflies and leafhoppers such as the green mosquito. The product has been developed with natural ingredients. When it encounters an insect, it blocks sodium and potassium channels that alter the transmission of nerve impulses in the insect, provoking hyperactivity and eventual death. More than 80 tests have been carried out on farms all over the world.
Improved drought tolerance through seaweed priming
A plant’s natural defense capabilities that can be stimulated to react to pests, diseases or abiotic stress like drought or salinity. Priming… Read more
A plant’s natural defense capabilities that can be stimulated to react to pests, diseases or abiotic stress like drought or salinity. Priming technology – a form of pre-conditioning of tissues – can support plants in activating their natural defense systems, so they respond more efficiently to an attack. By applying a chemical agent that stimulates priming, the plant is put on a state of alertness, thereby minimizing any damage caused by a potential stressor [1]. The biostimulant Super Fifty (SF) produced from the brown algae Ascophyllum nodosum reduces the accumulation of reactive oxygen species (ROS) which typically stifle plant growth during drought. At the same time relative water content remains high in SF-treated plants, while ion leakage – a measure of cell damage – is reduced. BioAtlantis now has a portfolio of six different bioactive priming products for application to crops.
Pest species such as armyworm, which feeds maize, sorghum and millet, have spread due to a warmer climate. It is especially destructive in Sub-Saharan Africa. Armyworm could potentially cost 10 of the continent’s major maize producing economies between USD 2.2 and 5.5 billion a year in lost maize harvests.[1] Oxitec is a developer of biological solutions to pest control. They work by releasing genetically-engineered male insects with a self-limiting gene into the environment. When they reproduce with wild females, their offspring inherit a copy of this gene and do not survive to adulthood, resulting in a reduction in the pest insect population. This method can be used to control many different kinds of insect pests. Oxitec’s technology is now being used to combat the autumn armyworm and improve agricultural outcomes.
Photo-selectivity meshes on fruit and crop cultivations can provide protection against direct solar radiation, birds and insects. They also help… Read more
Photo-selectivity meshes on fruit and crop cultivations can provide protection against direct solar radiation, birds and insects. They also help regulate humidity, shade and temperature. This technology consists of plastic nets integrating light-dispersive and reflective elements such as chromophores (scattering of light that favors plant growth). This type of mesh is conducive to floral and vegetable growth as it reduces solar stress while avoiding excess shade. Different colors of mesh can be used to manipulate the radiation reaching different plants, so as to stimulate plant growth. Blueberries for example produce a higher yield with black netting compared to other colors.
Pairwise, an agricultural gene-editing company supported by Monsanto (now Bayer), uses CRISPR proteins to target and edit plant DNA. The goal is… Read more
Pairwise, an agricultural gene-editing company supported by Monsanto (now Bayer), uses CRISPR proteins to target and edit plant DNA. The goal is to assist farmers by providing new varieties of crops that require less growing resources. The company focuses on CRISPR-Cas9 applied research to improve agriculture, and supports researchers in applying technologies to reduce food waste, limit pesticides and improve drought resistance. The company has also used its gene-editing platform to develop branded leafy greens, seedless berries and pitless cherries.
Google's parent company Alphabet has unveiled prototype robots to gather crop data. These rover robots – collectively nicknamed "Don Roverto" –… Read more
Google's parent company Alphabet has unveiled prototype robots to gather crop data. These rover robots – collectively nicknamed "Don Roverto" – measure crop traits by rolling through fields on upright pillars and capturing imagery of each plant. Machine learning is then used to identify traits such as leaf count, leaf area, leaf color, flower count, plant count and pod dimensions. This process of tracking plant characteristics and how they respond to the environment, called phenotyping, is normally slow and manual. The rover robots reportedly operate at far greater speed, frequency and accuracy than has previously been possible. For example, they have allowed researchers to observe closely the components
Extreme weather events, drought, soil salinization and pests exacerbated by climate change are leading to multi-billion dollar crop yield losses.[26][27]… Read more
Plants and food security under threat
Extreme weather events, drought, soil salinization and pests exacerbated by climate change are leading to multi-billion dollar crop yield losses.[26][27] This poses significant risks to food security, especially for the most vulnerable countries and populations. At the same time as rising temperatures are extending the growing season and may increase crop yields in Northern altitudes,[28][29] major grain-producing regions are witnessing decreasing productivity. Globally, maize yields are expected to decrease by nearly a quarter by 2050.[30] But this risk can be reduced. Climate-adapted crops may be one pathway to more resilient food systems. Promoting such crops can have the important added mitigation benefit of improving carbon sequestration and storage in the soil.[31] Read less
Toward climate-resilient plants
All crops are adapted to their particular climate. But the severe consequences of rapid climate change mean some crops must be adapted fast to the new reality. The most basic plant breeding technique is the identification, purposeful selection… Read more
Toward climate-resilient plants
All crops are adapted to their particular climate. But the severe consequences of rapid climate change mean some crops must be adapted fast to the new reality. The most basic plant breeding technique is the identification, purposeful selection and propagation of plants that perform better than others. The selection and development of crops with specific properties was once driven by the need to feed a growing population. However, breeding targets are increasingly being defined by a plant’s ability to resist climate impacts like drought.[32] Crop resilience has traditionally been strengthened through techniques that diversify crops and integrate farming systems. These include intercropping, shifting cultivation or agroforestry systems combining crops, trees and even animals on the same land. Other solutions have focused on providing physical protection for crops against external stressors. These include polytunnels (plastic-based crop covers) and insect nets. Meanwhile, the market for crop protection such as agrochemical pesticides has almost doubled in the last 20 years.[33] Today, the unprecedented challenges created by growing populations, changing consumer demand and intense climate pressure is accelerating the development of new technologies for climate-resilient species. Read less
The genome era continues
Genetic engineering of crops is not new. However, new gene editing technologies, such as CRISPR/Cas-9, are allowing rapid and more precise modifications. Compared to conventional breeding techniques, these new technologies may enable a… Read more
The genome era continues
Genetic engineering of crops is not new. However, new gene editing technologies, such as CRISPR/Cas-9, are allowing rapid and more precise modifications. Compared to conventional breeding techniques, these new technologies may enable a faster development of climate-smart crops that improve yields, resist diseases and tolerate stressors like drought, flooding and salinity. While genetically-modified crops (GM crops) combine genes from different sources, gene-editing technologies such as CRISPR can make small changes to a plant’s own DNA without introducing foreign genetic material. Although only a few companies own a patent to these key gene-editing tools, they are becoming increasingly accessible through licensing agreements. Users of these innovations are at present mostly found in Europe, Japan and the United States.
Gene editing is increasingly used in combination with other technologies such as indoor farming to optimize yield and reduce costs for relatively expensive farming systems.[34] Technological developments can also be seen in relation to triggering a plant’s natural defenses (chemical priming), growth-stimulating bacteria and the study of favorable genetic traits through AI and machine learning. All these technologies are thought to have a huge potential for next-generation agriculture.[35] Read less
From lab to field to fork
Advances in genome editing and other frontier technologies are gaining greater consumer and regulatory acceptance. But they still face legislative barriers and public resistance. Heated debates over the merits and risks of genome editing have… Read more
From lab to field to fork
Advances in genome editing and other frontier technologies are gaining greater consumer and regulatory acceptance. But they still face legislative barriers and public resistance. Heated debates over the merits and risks of genome editing have closed many markets to GM crops. Short- and longer-term issues need to be carefully considered when modifying plant genomes and cultivating them in the open. They include GM crops becoming invasive, build-up of resistance in target pests, cross pollination to related species, allergens and toxicity.[36] Nonetheless, these innovations may offer part of the solution to feeding a fast growing world population under uncertain climatic conditions. Simply banning a technology on grounds of principle risks foregoing solutions that could be much needed and even necessary.
Genome editing plants is not simple. It is not necessarily the case that advantages obtained in controlled environments will apply to a crop when used in real-world and less perfect environments. Genome editing has been applied to more than 40 crops across 29 countries. But even though 17 million farmers are planting GM crops,[37] relatively few have been approved for commercialization. Food crops cultivated in some countries using genome-edited varieties are soybean, canola, rice, maize and mushroom. Most have been engineered to tolerate a specific herbicide or be toxic to specific pests.[38]. When harvested, they cannot be sold on all markets. The major actors in genome-edited varieties are often multinational corporations and large-scale farmers, raising concerns over options and conditions for smallholder farmers.[28] With evidence of market concentration, especially in the seeds and biotechnology industries,[39] the success of these technologies must be coupled with efforts to ensure they are safe and beneficial to resource-poor farmers in areas most in need of crops that can withstand climate stresses. Read less
REDD stands for “Reducing Emissions from Deforestation and forest Degradation”. The “+” represents forest conservation and management.
FAO (2021c). The state of food and agriculture 2021. Food and Agriculture Organization of the United Nations (FAO). Available at: https://www.fao.org/3/CB4476EN/online/CB4476EN.html [accessed August 2022].
Allen, C.D., D.D. Breshears, and N.G. McDowell (2015). On underestimation of global vulnerability to tree mortality and forest die-off from hotter drought in the Anthropocene. Ecosphere, 6(8), 1-55.
Ibrahim, A., R.C. Abaidoo, D. Fatondji and A. Opoku (2016). Fertilizer micro-dosing increases crop yield in the Sahelian low input cropping system: A success with a shadow. Soil Science and Plant Nutrition, 62(3), 277–88.
Sebnie, W., M. Mengesha, G. Girmay, T. Feyisa, B. Asgedom, G. Beza and D. Dejene (2020). Evaluation of micro-dosing fertilizer application on sorghum (Sorghum bicholor L) production at Wag-Lasta Areas of Amhara Region, Ethiopia. Scientific Reports, 10(1), 6889.
FAO and FILAC (2021). Forest governance by indigenous and tribal people. an opportunity for climate action in Latin America and the Caribbean. United Nations Food and Agriculture Organization (FAO) and Fund for the Development of Indigenous Peoples of Latin America and the Caribbean (FILAC).Santiago, Chile: FAO. Available at: https://www.fao.org/documents/card/en/c/cb2930en/
World Bank (2021a). Opportunity assessment to strengthen collective land tenure rights in FCPF countries. Social inclusion in climate finance. Washington, DC: World Bank. Available at: https://openknowledge.worldbank.org/handle/10986/36499.
Gerster-Bentaya, M. (2013). Nutrition-sensitive urban agriculture. FoodSecurity, 5, 723-37.
Beacham, A.M., L.H. Vickers, and J.M. Monaghan (2019). Vertical farming: a summary of approaches to growing skywards. The Journal of Horticultural Science and Biotechnology, 94(3), 277-283.
Agrawala, S., C. Bordier, V. Schreitter and V. Karplus (2012). Adaptation and innovation: An analysis of crop biotechnology patent data. OECD Environment Working Papers, Paris: OECD. Available at: www.oecd-ilibrary.org/environment/adaptation-and-innovation_5k9csvvntt8p-en
Nishimoto, R. (2019). Global trends in the crop protection industry. Journal of Pesticide Science, 44(3), 141-147.
Azis, F., M. Rijal, H. Suhaimi and P.E. Abas (2022). Patent landscape of composting technology: A review. Inventions, 7 (2) Available at: www.mdpi.com/2411-5134/7/2/38.
FAO (2015). Climate change and food security: risks and responses. Rome: Food and Agriculture Organization of the United Nations (FAO). Available at: https://www.fao.org/3/i5188e/I5188E.pdf
Singh, A. (2021). Soil salinity: A global threat to sustainable development. Soil Use and Management, 38.
IPCC (2022). Working Group II Sixth Assessment Report. Impacts, adaptation and vulnerability. Summary for policymakers. Geneva: Intergovernmental Panel on Climate Change. available: https://www.ipcc.ch/working-group/wg2/
Wiebe, K., H. Lotze-Campen, R. Sands, A. Tabeau, D. van der Mensbrugghe, A. Bieweld, B. Bodirsky, S. Islam, A. Kavallari and D. Mason-D’Croz (2015). Climate change impacts on agriculture in 2050 under a range of plausible socioeconomic and emissions scenarios. Environmental Research Letters, 10(8).
González Guzmán, M., F. Cellini, V. Fotopoulos, R. Balestrini and V. Arbona (2022). New approaches to improve crop tolerance to biotic and abiotic stresses. Physiologia Plantarum, 174(1).
Li, J., L. Pu, M. Han, M. Zhu, R. Zhang and Y. Xiang (2014). Soil salinization research in China: Advances and prospects. Journal of Geographical Sciences, 24(5), 943–60.
FAO (2017). Chinese scientists develop rice that grows in seawater, potentially creating food for 200 million people. Food and Agriculture Organization of the United Nations (FAO). Available at: https://www.fao.org/in-action/agronoticias/detail/en/c/1060351/ [accessed October 2022].
Qian, Q., F. Zhang, and Y. Xin (2021). Yuan Longping and hybrid rice research. Rice (N Y), 14(1), 101.
Zafar, M.M., A. Razzaq, M.A. Farooq, A. Rehman, H. Firdous, A. Shakeel, H. Mo and M. Ren (2020). Insect resistance management in Bacillus thuringiensis cotton by MGPS (multiple genes pyramiding and silencing). Journal of Cotton Research, 3(1), 33.
Zhu, X., R. Clements, J. Haggar, A. Quezada and J. Torres (2011). Technologies for climate change adaptation – Agriculture sector. UNEP DTU Partnership. Available at: https://backend.orbit.dtu.dk/ws/portalfiles/portal/5706575/Technologies_for_Climate_Change_Adaptation_Agriculture_sector.pdf.
Brown, C. (2015). Improving modern agriculture through 'intercropping'. Yale Environment Review,
Day, R., P. Abrahams, M. Bateman, T. Beale, V. Clottey, M.J.W. Cock, Y. Colmenarez, N. Corniani, R. Early, J. Godwin, J. Gomez, P. González-Moreno, S. Murphy, B. Oppong-Mensah, N. Phiri, C. Pratt, S. Silvestri and A. Witt (2017). Fall armyworm: Impacts and implications for Africa. Outlooks on Pest Management, 28, 196–201.