Research on Rice Production and Quality

I. Rice Variety Improvement

1. ‘Taichung Sen 197’:

   Released in 2016, ‘Taichung Sen 197’ is a hard indica rice variety developed for food processing. Compared with conventional hard indica varieties, which generally require an aging period of 9 to 12 months, this variety becomes suitable for processing after only 6 to 9 months. It is suitable for producing rice vermicelli, steamed rice bowls, radish cakes, taro cakes, and other processed rice products, thereby contributing to greater diversity in Taiwan’s rice-based foods.

2. ‘Taichung Sen 198’:

   Released in 2018, ‘Taichung Sen 198’ is a soft indica rice variety. While retaining the desirable characteristics of ‘Taichung Sen 10’, it produces a 5% to 10% higher grain yield and has a greater bulk density, which can reduce storage costs. It provides an alternative variety for the replacement and renewal of soft indica rice cultivars.

3. ‘Taichung Sen 199’:

   Released in 2021, ‘Taichung Sen 199’ is the first indica rice variety developed by using molecular marker-assisted selection to introduce three bacterial blight resistance genes into ‘Taichung Sen 10’ through hybridization. The variety has substantially improved resistance to bacterial blight while retaining the high-yielding and high-quality characteristics of ‘Taichung Sen 10’. It is suitable for pesticide-reduction programs and organic or environmentally friendly cultivation systems.

4. ‘Taichung 200’:

   Released in 2022, ‘Taichung 200’ is a semi-waxy rice variety with a low amylose content. It has a low incidence of chalkiness, an attractive grain appearance, and a soft and sticky cooked-rice texture. In addition to conventional white-rice consumption, it is particularly suitable for consumption as brown rice or germinated rice, providing a new whole-grain and high-fiber rice option for consumers.

II. Improvement of Rice Cultivation Technologies

1. Development of Summer Single-Crop Rice Cultivation Technology:

   Research on summer single-crop rice cultivation technology began in 2015, together with the selection of suitable rice varieties. This cultivation system shifts the rice-growing period to May through October, reduces fertilizer inputs, and makes use of abundant summer rainfall to decrease irrigation demand. It can also be integrated with the rotation of different upland crops, thereby increasing the flexibility of domestic grain production and contributing to a higher food self-sufficiency rate.

2. Smart Irrigation and Intelligent Management of Rice Production:

   To improve labor efficiency in rice production and advance precision crop management, the research team joined Taiwan’s smart rice agriculture research program in 2019. Research topics include smart irrigation systems, precision panicle-fertilizer application based on unmanned aerial vehicle remote sensing, AIoT-based field management, and artificial intelligence systems for rice-plant identification. In addition to agricultural research institutions, collaborative partners include Guoxing Information Co., Ltd., National Chung Hsing University, National Tsing Hua University, Sanguang Rice Co., Ltd., and Lianmi Enterprise Co., Ltd. These industry–government–academic partnerships support the practical implementation of newly developed technologies.

3. Cultivation Technology and Seed Purification of Enaku Aromatic Glutinous Rice:

   Enaku aromatic glutinous rice, cultivated in Qin’ai Village, Ren’ai Township, Nantou County, is a distinctive rice variety associated with the local Indigenous community. Its production and cultural continuity have been affected by varietal admixture and emerging pests and diseases associated with climate change. The station has provided farmers with training in seed purification, including independent seedling production and the removal of off-type plants, to improve seed quality. Microbial agricultural inputs have also been introduced, together with the development of organic and environmentally friendly cultivation practices, enabling farmers to maintain production while supporting environmental and ecological sustainability.

4. Wet and Dry Direct Seeding of Rice:

   To reduce the time, labor, and financial costs associated with seedling production, research on rice direct-seeding systems was resumed in 2017, covering both wet and dry direct seeding. To address problems previously associated with direct seeding, including bird damage and floating seedlings, Japanese direct-seeding systems were used as a reference for developing iron-powder-coated rice seed technology. The station also collaborated with local material manufacturers to develop specialized iron powder suitable for rice direct seeding under Taiwanese conditions. Integration with unmanned aerial vehicle seeding has further improved operational efficiency and reduced production costs. Dry direct seeding additionally reduces seedling-production requirements and provides field-level water-saving benefits.

5. Research on Low-Carbon Rice Production:

   In response to Taiwan’s goal of achieving net-zero agricultural emissions by 2040, the station established carbon-footprint information for rice products and conducted carbon-reduction research targeting three major emission sources: field emissions, fertilizer manufacturing, and rice processing and milling. The results indicate that alternate wetting and drying, intermittent irrigation, and postharvest removal of rice straw from fields can reduce methane emissions. Rational fertilizer application and timely harvesting can also reduce carbon emissions associated with fertilizer manufacturing and grain drying. These practices provide a basis for future low-carbon rice production strategies.

6. Yield-Stable Intermittent Irrigation for Greenhouse Gas Mitigation:

   The timing and depth of irrigation are adjusted according to the developmental stages of the rice crop. Grain yield under this intermittent irrigation system does not differ significantly from that under conventional irrigation, while field greenhouse gas emissions are reduced. The technology therefore supports both stable rice production and agricultural carbon-emission reduction.

7. Research on Cultivation Practices for Adaptation to High-Temperature Conditions:

   To address the deterioration of rice quality caused by high temperatures during the later stages of crop development, nitrogen is applied at an appropriate rate during the grain-filling stage. This practice improves grain filling and reduces the formation of chalkiness, providing a high-temperature adaptation strategy that maintains both grain yield and appearance quality.

III. Research on Rice Quality

1. Establishment of a Data Platform for Rice Quality and Starch Properties:

   Domestically cultivated rice varieties are used to establish a database covering grain appearance, physicochemical properties, starch characteristics, glycemic index, and genes associated with starch biosynthesis. Surveys and evaluations of the appearance, freshness, physicochemical properties, and eating quality of commercially available domestic and imported rice have also been completed. The resulting data can support rice breeding, rice product selection, and the development of new rice-based products.

2. Selection of Rice Varieties Suitable for Rice Burgers:

   The station collaborated with Xisheng Enterprise to investigate relationships between textural properties and eating quality among different japonica rice varieties used for rice-burger patties. Rice harvested during the second cropping season of 2017 was processed into rice-burger patties by Xisheng Food Co., Ltd. and evaluated through sensory analysis and instrumental texture measurements. The results showed that ‘Taikeng 9’ was softer and stickier than ‘Tainan 11’ in terms of hardness, adhesiveness, and cohesiveness. ‘Tainan 16’ exhibited slightly greater hardness, whereas ‘Taichung 194’ had the best overall performance and was considered suitable for producing high-quality rice burgers.

3. Modernized Sensory Evaluation:

   International and national standards for sensory analysis, including relevant ISO standards, have been incorporated into the evaluation system. Standardized requirements have been established for the sensory-testing environment, sample preparation, evaluation procedures, and panelist training. These measures provide a stable and scientifically supported setting for rice sensory evaluation and improve the consistency and reliability of cooked-rice eating-quality assessments.

4. High-Throughput Rice Quality Inspection Technology:

   Artificial intelligence and deep-learning-based image analysis are applied to rice quality inspection. Rice-grain images are collected and annotated to train deep learning models capable of identifying chalkiness and automatically evaluating grain appearance quality. The technology is intended to improve inspection throughput, objectivity, and data consistency.