The population of the world is expected to rise up to a total of 9.7 billion from the current 7.3 billion by the year 2050. Due to the significant climate change that the world is facing today, factors like pest outbreaks and increased abiotic stresses are negatively affecting tropical crop production. This is particularly worrying because the increasing population, in further leading to climate changes, and these climate changes, are negatively affecting crop production. If the pattern continues, it may lead to a lack of food to meet the rising population demand and increased hunger amongst the populations. Alterations in the conventional breeding techniques have positively impacted the productivity of the crops. However, this is still not enough to meet the rising demand for food. There is a need for new technologies like the CRISPR system that allows genome editing for counteracting the emerging challenges in the agriculture industry.
Population Growth and Increased Need for Food
The world is currently faced with multiple challenges, which include the rising population growth, changes in climate, and a significant food shortage in numerous parts of the world. It has also been reported that the rate of population growth is much more than in other regions, which means that there is an even greater food demand in these areas. Out of the nine countries which are expected to grow by 50% in population by 2050, 7 belong to Tropical areas. These include India, Nigeria, the Democratic Republic of the Congo, Ethiopia, Indonesia, the United Republic of Tanzania, and Uganda. Out of all these countries, Nigeria is estimated to be the largest in population by 2050 and falls right behind China and India. Moreover, studies also show that almost 2/3rd of the population living in tropical countries are living in extreme poverty, and the ability to feed this population in tropical countries is estimated to become a critical issue in the coming future. In order to keep up with the rise in population growth, it is suggested that food production should also be increased by at least 50% by 2030 and 70 to 100% by 2050. (1)
Why is Gene Editing Required for Climate Change?
Even though it has been slow and progressive, a significant climate change has been noticed all over the globe over the years, and it only continues to get worse. A majority of the countries have introduced different policies and brought changes in their countries which will help overcome the side effects of these climate changes, one of which is the negative effects on the global food systems. However, studies have shown that as the temperature continues to get warmer and the carbon dioxide levels continue to rise, agriculture productivity is only expected to go down globally and affect the livelihood of many. This is where the role of Gene editing comes in, as it allows certain changes to be made in different crops to make them more resilient to climate changes and allow their continued production. Experts have claimed the CRISPR system to be a promising solution to the accelerated change in climate with is affecting crop quality and productivity at a drastic rate. (2)
What is the CRISPR- Cas9 System?
CRISPR stands for Clustered Regularly Interspaced short palindromic repeats, which are composed of groups of DNA sequences found in bacterial and archaeal genomes. These DNA fragments originate from bacteriophage, which has infected prokaryotes. CAS 9 stands for CRISPR-associated protein nine and essentially acts as an enzyme that involves the CRISPR sequences as a guiding tool to cause cleavage of DNA sequences that are complementary to the CRISPR sequence. The CRISPR system works with the CAS-9 proteins, and together they form a CRISPR-Cas9 system that can be used as a basis of gene editing within different organisms. This system has a lot of applications in the biological world which includes research, development of different biological products, which might provide an advantage to the populations, and also the treatment of diseases.
CRISPR-Cas9 for Improving Crops
New studies are proving the increasing benefits of the CRISPR/Cas9 system for improving agricultural production. There are now numerous applications of this gene-editing system for the improvement of tropical crops, which have already been affected the climate change. The editing of the genome of specific target nucleases has resulted in promising results and a hope that the growing population’s food demands may be able to be met in time. The system does not only increase the overall production of crops and improve the yield but also enable abiotic stress tolerance, enhance resistance to numerous pest infections and disease and allow the modification of plants to improve their overall quality. (3)
Rice is a very popularly consumed food all over the world and is reported to fulfill the calorie requirement of almost half of the world’s population. As the population continues to increase in the majority of the regions of the world, there will be continuous demands for food, which can be successfully met with increased rice production. One way to ensure a greater amount of rice available for the population consumption is to reduce the losses caused by increasing abiotic and biotic stress on the rice fields due to climate change. Global warming does not only affect the quality of the rice but the quantity as well, which can be corrected by the use of the CRISPR system. The CRISPR-Cas9 technology allows the production of climate-smart crops of rice, which are able to sustain greater climate challenges and produce a greater quantity of rice despite the adverse conditions. This is made possible by genetic engineering, where certain favorable genetic factors and phenotypes allow the different agricultural crops like rice to develop resistance against the abiotic stresses and global warming-associated challenges. (4)
Certain diseases like Brown Streak, Mosaic, and Bacterial Blight can cause significant loss of the yield of different crops and increase the chances of food shortage for the local population. Cassava is a staple food of certain areas in Africa, which is grown by small-hold farmers. The CRISPR/Cas9 gene-editing system can be effectively used to improve the crop yield and livelihood of these individuals by making certain changes in the genome of these crops to make them more resistant to diseases like Cassava Brown Streak. (5)
- Clarke JL, Zhang P. Plant biotechnology for food security and bioeconomy. Plant Mol Biol. 2013 Sep;83(1-2):1-3. doi: 10.1007/s11103-013-0097-1. PMID: 23860797.
- Massel K, Lam Y, Wong ACS, Hickey LT, Borrell AK, Godwin ID. Hotter, drier, CRISPR: the latest edit on climate change. Theor Appl Genet. 2021 Jan 8. doi: 10.1007/s00122-020-03764-0. Epub ahead of print. PMID: 33420514.
- Haque E, Taniguchi H, Hassan MM, et al. Application of CRISPR/Cas9 Genome Editing Technology for the Improvement of Crops Cultivated in Tropical Climates: Recent Progress, Prospects, and Challenges. Front Plant Sci. 2018;9:617. Published 2018 May 8. doi:10.3389/fpls.2018.00617
- Biswal AK, Mangrauthia SK, Reddy MR, Yugandhar P. CRISPR mediated genome engineering to develop climate smart rice: Challenges and opportunities. Semin Cell Dev Biol. 2019 Dec;96:100-106. doi: 10.1016/j.semcdb.2019.04.005. Epub 2019 May 10. PMID: 31055134.
- Gomez MA, Lin ZD, Moll T, Chauhan RD, Hayden L, Renninger K, Beyene G, Taylor NJ, Carrington JC, Staskawicz BJ, Bart RS. Simultaneous CRISPR/Cas9-mediated editing of cassava eIF4E isoforms nCBP-1 and nCBP-2 reduces cassava brown streak disease symptom severity and incidence. Plant Biotechnol J. 2019 Feb;17(2):421-434. doi: 10.1111/pbi.12987. Epub 2018 Oct 5. PMID: 30019807; PMCID: PMC6335076.