Yangang LIU, Lijuan LIU, Guixiu JIN, Xiangkui LI, Ruihua ZHANG, Jing WANG, Deyou LIU, Xiushan ZHAO

Linyi Academy of Agricultural Sciences, Linyi 276012, China

Abstract Tangya Tribute Rice is a famous and special product in Shandong Province, and it was awarded the National Geographical Indication Certificate trademark in 2011. This paper elaborated the specific production area, unique production environment, rich cultural history and unique product quality of Tangya Tribute Rice. In addition, from the aspects of choice of origin, variety selection, production management, timely harvesting and processing, it summarized the unique production methods of Tangya Tribute Rice. Besides, it discussed its development prospects, in order to maintain the brand quality of Tangya Tribute Rice to the greatest extent, and further improve the brand awareness and market competitiveness of Tangya Tribute Rice in the domestic and international markets.

Key words Tangya Tribute Rice, Linyi City, Geographical indication, Protection technique

1 Introduction

Tangya Tribute Rice, also known as Tangya Rice, Tangya Gongmi and Linyi Tangmi, is a famous and special product in Shandong Province. It is famous for its rare varieties, obvious characteristics and unique flavor. Tangya Tribute Rice is rich in medicinal and therapeutic value. In addition to specific production environment conditions, special cultivation management methods and rich human history, Tangya Tribute Rice was registered with the Trademark Office of the State Administration for Industry and Commerce (now the Trademark Office is affiliated to National Intellectual Property Administration) in July 2011 and obtained the right to use the geographical indication certification trademark[1-2]. Tangya Tribute Rice has a long history. It is named because it is produced in Datangya Village in Xigaodu Residential District of Luozhuang District of Linyi City. Since Tang Dynasty, the rice produced there had been collected by government for paying tribute, so it was called Tang Tribute Rice[3-10]. Tangya Tribute Rice, Xiaohe Lotus Root, and Shagou Taro are also known as the three major local products in Linyi City. Tangya Tribute Rice has a natural rich fragrance. After cooking, it is full of aroma and excellent taste; the quality of glutinous rice is the best raw material for making Lantern Festival, Zongzi, sticky cake and various high-quality pastries[3-11]. Tangya Tribute Rice is also rich in protein, iron, calcium, selenium and amino acids, and has certain medicinal value. Local villagers often use Tangya Tribute Rice, longan and black dates as nourishing food during the winter months[5, 9]. In 1985, it was rated as a special product of Shandong by the Ministry of Agriculture, Animal Husbandry and Fisheries[5-9, 11-14]. In this paper, we introduced the specific production area, unique production environment, rich cultural history and unique product quality of Tangya Tribute Rice. In addition, from the aspects of choice of origin, variety selection, production management, timely harvesting and processing, we summarized unique production methods of Tangya Tribute Rice. Besides, we discussed its development prospects, in order to maintain the brand quality of Tangya Tribute Rice to the greatest extent, and further improve the brand awareness and market competitiveness of Tangya Tribute Rice in the domestic and international markets.

2 Unique natural ecological environment

2.1 Soil landformThe production area is located on the Tancang Plain in the southeast of Shandong, the terrain is flat. The soil in the main producing area is mainly paddy soil. The soil is deep and fertile, with organic content 1.13%, total nitrogen 0.066%, hydrolyzed nitrogen 68 mg/kg, available phosphorus 8.9 mg/kg, available potassium 33 mg/kg, soil pH 6.9, suitable for rice cultivation.

2.2 Hydrologic conditionsThe production area is close to Xiaobudong Irrigation Area in Linyi City, has superior water conservancy conditions, sufficient groundwater sources, and supporting irrigation and drainage facilities in farmland. The water quality is clear and pollution-free. The amount of water can guarantee irrigation and drainage, and ensure the water demand for Tangya Tribute Rice during different growth periods.

2.3 Climatic conditionsThe production area belongs to a warm temperate monsoon zone with a semi-humid continental climate. The average annual temperature is about 12.5 ℃, the average annual sunshine time is about 2 450 h, the solar radiation is 497 kJ/cm2, the average annual rainfall is about 850 mm, and the frost-free period is 198 d. Hot and much rain occur simultaneously in summer. In autumn, the sunshine hour is long, and the temperature between day and night is large, which are favorable for rice growth and development.

2.4 Historic and cultural conditionsThe rice variety planted in Datangya Village in Xigaodu Residential District of Luozhuang District of Linyi City is called Shuiniupi, which has a long cultivation history. According to legend, Tangya Rice is also known as Xiamakan, which means some officials often come here to come down from the high-headed horse to watch[13-15]. A legend goes that, Emperor Taizong Li Shimin stationed there during the eastward fight. After eating Tangya rice, he expressed great praise. From then on, the rice planted there was collected as tribute to government, and won the name Tangya Tribute Rice[10-11, 13-16]. According to Annals of Linyi County, the planting of Tangya Rice has a history of more than 1 000 years. In the northwest of this village, there is a crescent moon pond circle, less than 1 000 m2, which is the land really producing Tangya Rice. The terrain is low-lying, wet throughout the year, the soil is black and yellow, and the temperature is warm. The dried soil is hard and indestructible, and remains unchanged after soaking for many days. According to the analysis of modern soil experts, the soil there contains a large amount of rare element-selenium. For the same variety, in this land less than 1 000 m2, the quality of the rice produced is better than other land, so Tangya Rice is very precious[13-15]. According toQiminYaoshu(alsoMainTechniquesfortheWelfareofthePeople)[18], the land requirements of rice are not strict, as long as the rice fields are replaced once a year. Choose a rice field, close to the upstream of the running water, no matter the land is fertile or barren, as long as the water is clear, rice will grow. The reason why Tangya Rice is famous is that it is closely related to the soil and water there. Both the water and soil are excellent, so the rice produced is excellent. Not only the local rice varieties have outstanding characteristics, even the varieties introduced from other places, after local cultivation, also have the flavor of Tangya Rice. After liberation, through the construction of water conservancy, the improvement of land and water management, and the reform of rice, this area has become a land of fish and rice[5, 9]. In the 1980s, a new variety of Luxiangnuo No.1[19-23]was selected from natural mutants of Linyi Tangya Rice which not only maintained the original flavor of Tangya Rice, but also solved the problems of falling grain and lodging; in 1992, it was recommended by the Ministry of Agriculture to participate in the "Thirteenth International Agricultural Expo" held in Italy, and was well received[24]. In 1993, Luozhuang District Supply and Marketing Tangya Rice Association was established, and in 1999, Linyi City Luozhuang District Jingjie Tangya Rice Processing Factory was registered. From the small workshop type processing in the past to the now fully automatic mechanized production, the quality of Tangya Tribute Rice has been comprehensively improved. On November 6, 2019, the first rice culture festival was held in Tangya Tribute Rice Planting Base in Xigaodu Residential District Office, Luozhuang District, which further enhanced the popularity and reputation of Tangya Tribute Rice.

3 Unique product quality

Tangya Tribute Rice has its excellent quality characteristics due to its unique natural ecological environment and specific production methods.

3.1 External sensory characteristicsTangya Tribute Rice is a long-grained fragrant japonica glutinous rice. The grain is purple-brown, unpolished rice is light green, and the polished rice is white like pearl. Compared with other rice, Tangya Tribute Rice has two major characteristics: First, it has a natural rich fragrance. For Tangya Tribute Rice, it is preferred to cook with strong fire. No matter porridge or cooked rice, mixing 3%-5% Tangya Tribute Rice, it will give out rich fragrance, and the taste will be excellent. There is the reputation of "one family cooking Tangya Tribute Rice, all neighbors can smell the fragrance". Second, Tangya Tribute Rice is highly glutinous. Glutinous rice cake, stuffed dumplings and Zongzi made of Tangya Tribute Rice are glutinous and creamy. Even the recooked Tangya rice, the glutinous feature and fragrance are like the originally cooked rice. Thus, Tangya Tribute Rice has become the top quality raw materials for high grade rice of large restaurants and hotels.

3.2 Internal quality indicatorsAccording to the laboratory analysis of the Shandong Academy of Agricultural Sciences, the brown rice rate of Tangya Gong rice is 81.6%, the polished rice rate is 73.1%, the crude protein content is 10.09%, the crude fat content is 3.41%, the soluble sugar content is 1.91%, and the starch content is 79.27% (straight chain starch content 1.25%, amylopectin content 98.75%), and the gelatinization temperature is low. Vitamin B121.8 mg/g, vitamin B20.28 mg/g, amino acid content 9.76%, of which lysine content reaches 0.31%. Tangya Tribute Rice is rich in nutrients and is an ideal health food.

4 Specific production methods

4.1 Origin selectionThe production area of Tangya Tribute Rice is in Xigaodu Residential District of Luozhuang District of Linyi City, namely, starting from Binhe Avenue in the east, Shenpaizi Village in the west, Donggaodu Village in the north, and Hongsheng New Village in the south. The main production area is close to the Xiaobudong Irrigation Area in Linyi City. The terrain is flat and the irrigation and drainage facilities of the farmland facilities are matched. The quality of the irrigation water meets the requirements of national standard GB 5084-2005, and the environmental quality of the production area meets the requirements of standard NY/T 5010-2016.

4.2 Variety selectionTangya Tribute Rice is an ancient farm variety in Linyi City. It was originally a mixed group with many varieties. Luxiangnuo No.1 with the most distinctive Tangya Rice characteristics was selected as the main planting variety. The production base was provided with isolation belts to prevent pollination with other varieties of cross-flowers. The seed quality meets the provisions of national standard GB 4404.1-2008.

4.3 Production management

4.3.1Cultivating seedlings to appropriate age and strengthening seedlings. When raising seedlings, moisture should be adequate, to ensure complete and strong seedlings. The main stems of the seedlings of this variety are thick and thin, and the tillers are weak. The colony mainly depends on the main stem, and should be sparsely bred to grow strong seedlings. Generally, planting is preferred in early May, because the 1 000-grain weight of this variety is higher, the planting amount is about 900 kg/ha.

4.3.2Reasonable dense planting. This variety has weak tiller strength, so it needs wide row spacing and small clusters of dense planting, and its yield increases with the increase of density in the range of 1.5-3.0 million/ha basic seedlings. The suitable row spacing is 20-22 cm, the cluster spacing is 8-10 cm, 5-6 plants per cluster, the basic seedling is about 2.910 million/ha. The suitable seedling transplanting period is late June. For example, if the temperature is too low during the grain filling stage, the normal maturity will be affected.

4.3.3Scientific management of fertilizer and water. (i) Proper fertilization. This variety has a large growth quantity at seedling stage, a large number of spikelets, a long grain filling time and needs much fertilizer at the later stage. Fertilizer and water should keep the principle of "stable at the early stage, controlled at the middle stage, and promoting at the later stage". From seedling transplanting to jointing stage, it needs with an appropriate amount of base fertilizer. During the spike differentiation stage, proper fertilizer control should be taken to reduce the number of spikelets, and at the same time, it is required to control the excessive extension of the upper leaves. At the later stage, it is necessary to increase fertilizer and water, coordinate the absorption and conversion of nutrients, promote grouting, increase seed setting rate and 1 000-grain weight. (ii) Scientific irrigation. At the re-greening stage, it is required to establish water layer; during the spike differentiation to the grain filling stage, it is necessary to control the water layer and moisture. At other growth stages, it is necessary to take intermittent irrigation, improve field permeability, enhance root vitality, improve the photosynthetic conditions for middle and later stages of the colony, extend the leaf functional period, and improve the photosynthetic productivity for later stage of the colony[25]. Cut off the water 5-7 days before maturity, do not cut off the water too early.

4.3.4Prevention of diseases, insects and weeds. It is required to implement the plant protection policy of "prevention first, comprehensive prevention and control", the specific measures are as follows: drying seeds in the sun for 1-2 days before sowing, using ultraviolet rays to sterilize and remove insects, and increasing germination rate; soaking seeds with 25% prochloraz emulsifiable concentrate 3 000-4 000 times for 2-3 d (preferably not to germinate) to prevent seed-borne diseases; taking timely control ofChloethripsoryzae, Cicadellidae,Laodelphaxstriatellusand rice virus diseases at the seedling stage, making effort to transplant with pesticide and fertilizer; using high efficiency and low toxicity, low-residue pesticides prevent and control sheath blight, rice blast, rice false smut,Cnaphalocrocismedinalis, rice planthoppers,Chilosuppressalisand other diseases and pests in a timely and appropriate manner; for weeding, it is recommended to take artificial control and minimize the use of herbicides[26-27].

4.4 Harvesting and processing in suitable time

4.4.1Harvesting. When 90% of the rice husks appear purple-brown in early October, it is preferred to be harvested on a sunny day. Keeping a certain thickness when drying the rice to avoid excessive drying. It is feasible to use a dryer to dry at low temperature and put into the warehouse. When the moisture content of the rice is about 14.5%, it can be stored in the warehouse. It is necessary to take separate harvesting, transportation, threshing, storage, processing, packaging to prevent mixing with ordinary rice.

4.4.2Processing. Rice processing should comply with provisions of standard NY/T 5190-2002[28]. The processing technical process is as follows: rice cleaning → dust removal and stone removal → hulling → husk separation → rice milling → packaging → finished product storage.

5 Development prospects

To develop and strengthen Tangya Tribute Rice industry and build strong Tangya Tribute Rice brand, only relying on 1 000 m2land is far from enough. Through more than 1 000 years of cultivation, Tangya Tribute Rice has accumulated a complete set of cultivation management measures. In recent years, the Luozhuang District Party Committee and District Government of Linyi City have gradually expanded Tangya Tribute Rice to the production scale of 2 000 ha on the west bank of the Yihe River through measures such as improving policies for supporting agriculture and benefiting farmers, increasing financial investment, guiding scientific planning, and integrating land resources. Luozhuang District Supply and Marketing Tangya Rice Association was established relying on Tangya Tribute Rice brand. Using high-quality rice produced by the irrigation of Yihe River as raw material, through careful farming, high-quality rice is produced, which further improves the added value of Tangya Tribute Rice, maintains and enhances the market reputation and competitiveness of Tangya Tribute Rice, and promotes brand development of Tangya Tribute Rice. With the continuous improvement of people’s living standards, Tangya Tribute Rice with a long history and delicious fragrance will be popular in the market, the market potential is tremendous and the development will have a great prospect.