Cover the field with sheet mulch and drain the water when the mandarin oranges are growing. By suppressing the absorption of water from the roots, it is said that excellent mandarin oranges with a strong flavor can be produced. It seems that the life power of the mandarin orange tree is strengthened when stress is given by suppressing water absorption. As a result, the amount of fructose, which is sweeter than sugar, increases, producing a richer, more delicious mandarin orange.
Since the white sheet mulch that covers the ground of the mandarin orange field reflects sunlight well, photosynthesis (a huge protein complex lined up in the thylakoid membrane in the chloroplast transforms sunlight energy into energy that can be used by living organisms). ) is promoted, and it seems that oranges with a deep color and taste can be produced. In addition, the sheet mulch is made of moisture-permeable material, which has the function of blocking rain and at the same time allowing moisture in the ground to escape to the outside as water vapor, which seems to be able to drain water efficiently.
In Nagasaki Prefecture, one of the leading mandarin orange producing areas in Japan, Nagayo Town in Nishisonogi County is blessed with a warm climate facing Omura Bay and seems to be famous as a production area of Nagayo mandarin oranges. About 500 years ago, Unshu mandarin oranges were brought to Kagoshima from China, and in the history of Nagasaki, it is said that cultivation began in Nishisonogi District during the Tenmei era (1780-1788). With a history of more than 200 years, the town’s mandarin orange cultivation far outperforms rice and vegetables, and boasts a planted area that turns the entire mountain orange-colored in autumn, supporting Japanese agriculture. The harvested mandarin oranges are shipped to metropolitan areas such as Tokyo and Chiba, Ishikawa, Aomori, Hokkaido, etc. Overseas, it seems that they are also exported to Canada.
As the cultivation area for Unshu mandarin oranges is decreasing due to the slump in sales prices, etc., they are promoting the introduction of Tyvek mulch, aiming for stable production of high-quality fruits. The water resistance, breathability, moisture permeability, and light diffuse reflectance of Tyvek® Multi support stable production of high-quality, delicious citrus fruits (such as unshiu mandarin oranges). DuPont™ Tyvek® (a chemical manufacturer headquartered in Wilmington, Delaware, USA. The official company name is DuPont de Nemours. The Japanese corporation is DuPont Co., Ltd.) is a continuous ultra-fine polyethylene fiber of 0.5 to 10 microns. A sheet that is bonded by applying heat and pressure. It has excellent water resistance, breathability and breathability, and seems to have excellent durability. In addition, I have heard that flash-spun nonwoven fabrics manufactured from 100% high-density polyethylene (no additives) are considered to minimize the environmental impact at all stages from use to disposal.
In this area, the soil is covered with sheet mulch, which has been handed down from great farmers and predecessors, to control the moisture in the soil and at the same time to use the light reflection effect to cultivate many fruits with high sugar content and excellent coloring. But it seems to be progressing. In addition, as you all know, in recent years, national projects have started experimental cultivation using IT and AI.
It is one of the specialty products that represent Nagasaki Prefecture and Japan, and the conditions for producing delicious mandarin oranges are sunny, warm in winter, and with an annual average temperature of 15°C or higher. Surrounded by the sea on three sides, Nagasaki is affected by the Tsushima Warm Current and enjoys a warm climate throughout the year. Because there are many slopes and slopes, the sunlight hits each orange tree evenly compared to flat land. It seems that when the sun sets, the sunshine hours become longer, and the sunlight reflected from the sea surface makes the mandarin oranges grow juicy and plump.