In China, rice is an important part of the past, present and future. Already thousands of years ago, the Chinese were growing rice plantations and the plant is strongly rooted in the country’s tradition. Due to a growing population and the high demand, the yield of rice must continuously be increased while ensuring high quality standards. The search for rice for the future is goal of the research.
It comes barely as a surprise that rice is a staple food in China. Statistics show that the average Chinese consumes about 91 kilograms of rice per year. This is just over 18 times the amount of the annual rice consumption of a European. The average European consumes an average of 57.9kg of their staple food potatoes, which is significantly lower than the annual rice consumption in China.
The variety of rice is immense. The popular grain comes in all shapes and sizes. Not only the looks, consistency and taste of rice vary from grain to grain – there are also great qualitative differences.
The Shanghai Institute of Plant Physiology and Ecology is specializing on agricultural research and researching rice is part of this. The molecular and genetic basis of high-yield and high-quality rice is one of the institutes central areas of interest and ultimately their research has the purpose of promoting human health. The institute is pushing forward the research of biology and seeking to protect human health jointly with the seven other institutions that form the Shanghai Institutes for Biological Sciences of the Chinese Academy of Sciences.
China is home to vast fields of rice but just like in many other countries, scarcity of water and arable land are prevalent. With China’s rapidly growing population, increasing demands of rice need to be satisfied. Therefore, the rice varieties of the future must be high in nutrients, filling and robust. Studying rice is hence vital.
Life scientists at the Shanghai Institute of Plant Physiology and Ecology study rice for different reasons. Studying rice for the purpose of a greater yield is just one example. The research helps to, on one hand prevent the decrease of yield caused by weather, insects and bacteria; and on the other hand, to increase the yield using less fertilizers and pesticides. This can be achieved through studying every gene of a rice plant and subsequently modifying the genes gradually.
In terms of evaluating the quality of different rice varieties, researching the glume is vital. By looking at the thickness of the glume, the cell arrangement and vascular growth, scientists evaluate the quality of a rice plant. Directly under the glume is where the most nutrients are located and imaging results give scientists insights about the number and density of vitamins and minerals.
Vascular bundles enable the nutrient transport in plants. The organ can be compared to vessels in the human body. A greater number of vascular bundles can imply larger plant growth, as they strengthen the power of nutrients from roots to leaves. The number of vascular bundles and stem thickness of a rice plant are controlled by the coordination of many genes. This makes the research of rice very complex.
A grain of truth
Scientists have started to engage in the research of rice plants and its qualities a long time ago. Trips to rice plantations and the subsequent slicing of rice seeds, stems and roots used to be part of that research. With the help of a conventional light microscope, scientists can analyze the structure and accordingly the quality and yield of rice.
However, studying rice with light microscopy is not ideal for a number of reasons. The sample preparation of rice is lengthy and complex. A conventional light microscope can only depict objects with a limited depth, which is why in the past, scientists had to deal with numerous samples that require elaborated cutting and could not fully conceive the microstructure of the sample. This prevented researchers from getting optimal results and therefore, the traditional method of studying rice is not an ideal solution.
New ways of depicting structures of rice
With the aim to improve the quality of research results, the Shanghai Institute of Plant Physiology and Ecology and ZEISS partnered up. Knowing that more effective technologies to study rice are key, the two parties cooperated in regard to the imaging study of rice. Using X-ray technology, scientists conduct their research in a non-destructive manner.
The Shanghai Institute of Plant Physiology and Ecology obtained their research results by sampling rice with a ZEISS Xradia 520 Versa X-ray microscope. (The successor model is the ZEISS Xradia 620 Versa.) A sample is rotated in the focus of an X-ray beam and provides scientists with three-dimensional images. As the wavelength of X-rays is smaller than of visible light, the optical resolution of a 3D X-ray microscope is significantly higher compared to conventional light microscopes.
The results help the institute to visualize thousands of virtual slices of a rice plant and researchers can fully appreciate the microstructures inside a sample. Ultimately, this information is helpful to make statements about yield and nutrition of a particular type of rice.
Bringing forward the research of rice plants – new methods are not only making scientists’ hearts beat faster but also provide Chinese rice farmers with valuable information.