Foldscopes: A Swift and Low-Cost Technology Solution to Crop Loss

By Katya Frazier, Ian Kriel, Karen Chien

A low-cost and lightweight alternative to the compound microscope, a Foldscope presents an effective way to quickly determine size and viability of pollen and germination. Foldscopes can be used as a tool in agriculture to detect signs of environmental stressors, such as climate change, in which moderate droughts cause 40 to 50% loss of yield globally to crops. Expeditious and precise identification of pollen morphology and traits made possible by the Foldscope can be used to develop treatments against abiotic stresses and help re-establish growth trends against recent declines in global agricultural yields.

Pollen traits, such as viability; inhesion; and germination, are important for screening genotypes which can lead to higher grain yields and pollination efficiency. Conventional microscopes, such as compound microscopes, are too bulky, time-consuming, and pricey to efficiently conduct in vitro and in vivo experiments for pollen analysis. DIY microscopes are available to address this issue; however, a commercial mini microscope called Foldscope comes out as a superior cost-effective, accurate, and light model. 

Foldscopes are paper microscopes that use simple and small materials, such as LED lights and lenses. They can magnify 140x and, due to their small size, they are useful to use anywhere and very portable when necessary, including the pollen fields. Hence, the use of a Foldscope is vital for investigating pollen under various conditions due to its portability, affordability, and ease of use. 

Color and diameter are two of the many traits a Foldscope can image efficiently in pollen seeds, including pollen tube length characterized by germination and viability marked by a pink dye. As origami-based mini optical microscopes, Foldscopes can be put together within ten minutes and cost between $2 and $10 depending on the complexity of the microscope. The Foldscope comes out as a lightweight and low-cost alternative to the compound microscope’s price of at least a hundred US dollars. 
A fluorescent model of Foldscopes can be designed to master in vivo conditions at relative ease than other microscopes, making the future implementation of Foldscopes to study genetic variation and stigma traits in vivo a breakthrough in agriculture that no other microscopes have achieved so far. With its cost and time efficiency, Foldscopes have the potential to be a useful tool for various applications. Foldscopes serve as an important instrument for medical screening, biological research, ecological studies, and hands-on science education in schools and universities.

Citations

Rane, Jagadish, et al. “Calibration and Validation of the Application of Low-cost, Lightweight, and Portable Paper Microscopes for Monitoring Pollen Traits as a Screening Tool for Drought Tolerance.” South African Journal of Botany, vol. 148, Aug. 2022, pp. 694–703, doi:10.1016/j.sajb.2022.05.029.