Plant health and global food security


Dr Rajendra Paroda FTSE

Chair, Trust for Advancement of Agricultural Sciences

Nearly one billion people go hungry every day. And a significant amount of food is lost due to pests and diseases. Use of improved varieties, integrated pest management (IPM) and good agricultural practices (GAP) can help ensure good plant health – which is critical to achieve the SDGs by 2030. 

Plant Health for Achieving Sustainable Development Goals (SDGs)

Today the whole world celebrates the International Day of Plant Health, signifying the importance of crop plants for human survival. From the beginning of civilisation, the importance of quality seeds and healthy plants to guard against diseases, pests and natural disasters is well known. Globally, annual losses due to pests and diseases are estimated to be around $ 200-300 billion, with 10-40% of crop losses due to pests. Climate change is also adversely affecting plant health and threatening global food security. 

By 2050, the global population will be 10 billion, and will need 60% more food than today with less of natural resources such as land, water, and biodiversity. To meet the United Nations Sustainable Development Goals by 2030, especially thos relating to poverty (SDG1), zero hunger (SDG2), climate action (SDG13) and healthy life on land (SDG15), is a daunting task. Urgent action is needed at both the national and global level to raise healthy crops, while guarding against biotic and abiotic stresses as well as the impact of climate change. 

Pests and Diseases – Real Threat to Plant Health 

Plant pests and diseases pose serious threats to global food security.  There are several examples from around the world: a severe outbreak of Brown spot fungus (Helminthosporium oryzae) in West Bengal destroyed rice crops (50-90%) leading to over two million deaths (Bengal Famine, 1942-43), the potato late blight caused by Phytophthora infestans (Irish Famine, 1845) killed more than one million people in Ireland, and the Taro leaf blight (Phytophthora colocasiae) in 1993 caused almost 100% loss in Samoa thus threatening food security in the Pacific region.  

Over decades, wheat crops have also been affected adversely due to black, brown and yellow rusts as well as Karnal bunt. In the last two decades, the threat of virulent transboundary stem (black) rust Ug 99 – first noticed in Uganda and now spread to Iran – has been addressed through Borlaug Global Rust Initiative (BGRI) as 90% of wheat varieties are susceptible.  

More recently, the infestation of Fall Armyworm (Spodoptera frugiperda) in East Africa, Bangladesh and West Bengal in India has caused yield losses up to 40%.  

detailed view natural green wheat leaf with rust disease infestation

Wheat leaf affected by rust.

In India, prior to the release of genetically modified Bt cotton in 2001, the yield losses due to Bollworm (Helicoverpa armigera) required spray of chemical pesticides – almost half of the total quantity used in agriculture. Fortunately, Bt cotton has rescued smallholder farmers for over two decades now due to reduction in pesticide use by almost 40%. Adoption of genetically modified cotton thus enabled India to be the largest producer in the world and emerge as an important exporter. 

For containing transboundary diseases, effective quarantine measures at the national level are urgently required in developing countries. For instance, thanks to effective quarantine systems in Australia, there are no reports of Karnal bunt incidence in wheat and many other pests of other crops. Strong plant quarantine systems are, therefore, critical to guard against diseases and pests emerging in new host crops and the regions. 

In global production and exchange of vegetatively propagated food crops like banana, cassava, potato, yam, sweet potato and fruits like citrus, apple etc., certified planting materials will be critical for raising healthy crops and their quality produce. 

Crop Breeding to Improve Plant Health 

Plant genetic resources are crucial for global food, nutrition, and environmental security. Genetic enhancement through dwarfing and photo-insensitive genes in wheat and rice helped achieve the Green Revolution in South Asia. Revolution in sugarcane production also took place in India through nobilization of cane using wild germplasm. Nobilization also helped in spreading sugarcane production from tropical south to sub-temperate regions of north India due to earliness and tolerance to stem rot. 

In order to guard against adverse impacts of climate change, we urgently need the genes that are tolerant to drought, heat, cold, flood, diseases, pests, etc. There is also a need to intensify efforts for stacking multiple resistance genes using innovative genome editing (Crisper/Cas9) technology. This requires strengthening of plant breeding efforts at the global level, including strong partnership between NARS and CGIAR, and with the private sector. 

As per the FAO study, plant breeding efforts have invariably declined in many developing countries. Hence, a Global Initiative on Plant Breeding (GIPB), supported by Bill and Melinda Gates Foundation (BMGF), is being implemented by FAO in developing countries.  

Female scientist in protective mask and gloves examining small green sprouts growing under UV lamps in laboratory of agricultural farm

Promoting the Concept of ‘One Health’  

Though the UN had declared 2020 as the International Year of Plant Health, somehow its importance got overshadowed by the COVID-19 Pandemic. On the contrary, the importance of ‘One Health’ could gain considerable prominence. ‘One Health’ is an integrated, unifying approach that aims to sustainably balance and optimise health of soils, plants, animals, and people under varying ecologies. Food security is a major goal of ‘One Health’ as it embraces healthy food production, processing, value chain and marketing. Therefore, all stakeholders including farmers, consumers, researchers, private sector, NGOs and the government officials, need to work towards sustainable food production in a coordinated manner in order to raise healthy crop plants to meet our food and nutritional security needs. We also need to develop automated plans for pest and disease outbreak prediction and associated management systems for our major food crops.  

millet or sorghum plant views in a farmland,cultivation pearls millet fields,pearls production of beer and wine,fields of pearl millets ( bajra )

Millet nutri-grains which are tolerant to drought, heat, pests and diseases and nutritionally superior in protein, fibre, minerals and vitamins, compared to rice and wheat.

Crop Diversification for Sustainability 

Agricultural diversification towards remunerative and high value crops such as vegetables, fruits, condiments, spices, medicinal plants, etc. will increase farmers’ income and reduce poverty. We should promote the recently eveolved use of biofortified varieties in cereals, millets, pulses, oilseeds, vegetables, and fruits that produce high nutritive value and low anti-nutritional factors.  

2023 is the International Year of Millets – nutri-grains which are tolerant to drought, heat, pests and diseases and nutritionally superior in protein, fibre, minerals and vitamins, compared to rice and wheat. Their enhanced use in the food basket would help address specific concerns of global hunger. The recent UN Food Systems Summit also emphasized the need to strengthen research on local food crops and support their greater use. 

Shifting away from cereal-centric cropping systems to a more diversified (cereal-legume based) integrated farming systems will be more sustainable. This will help conserve natural resources and promote regenerative agriculture. Crop diversification and growing of healthy crops have so far helped achieve global food security. However, reorientation around local food systems being more resilient and adapted, and using seeds of healthy plants, will help achieve greater agricultural sustainability.  

Dr Rajendra Paroda FTSE

Chair, Trust for Advancement of Agricultural Sciences

Dr Rajendra Paroda is an acclaimed agricultural scientist specialising in plant genetics and breeding. His contributions to plant breeding and genetic resource management are globally recognised and include establishing the first modern national genebank in India. 

As Secretary, Department of Agricultural Research and Education, he modernised India’s agricultural research system, creating more than 30 new research institutes. The resulting innovations doubled India’s food grain production from 130 million tons in 1980 to 260 million tons in 2011, underpinning food security for a rapidly growing population. 

Rajendra’s outstanding contributions have strengthened agricultural research and innovation internationally, particularly in Asia and the developing world. He established and then led key international bodies, including the Global Forum on Agricultural Research (GFAR) and the Asia-Pacific Association of Agricultural Research Institutions (APAARI). 

Rajendra has a long association with Australian scientists and organisations, including CSIRO. He served on the Advisory Council of the Australian Centre for International Agricultural Research.