Tian Jing is an annual herb of the legume family, with strong salt and alkali resistance, barrenness and flood resistance, rapid growth, strong stress resistance, is a pioneer plant along the beach, saline alkali land, drought and barren land, and is also a high-quality green manure. Tian Jing's nodules and stem tumors can fix nitrogen, nitrogen fixation capacity is 20-30 times higher than soybeans, plant height, fast growth, high biological yield, crude protein content is also very high, so it is widely used to improve soil, organic fertilizer, papermaking, extraction of field gum, oil extraction, protein extraction and other aspects.
Morphological characteristics
It is native to the tropical regions of the Eastern Hemisphere. China was the earliest planted in Fujian, Taiwan and Guangdong, and gradually moved north to the Jianghuai River Basin. It is also cultivated throughout the north. The root system is developed, mostly distributed in the soil layer of 20 to 40 cm, and the nodules are many and large.
Strong nitrogen fixation capacity. In the case of flooding, spongy tissue and adventitious roots can form, and nodal tumors can also occur. The plant is more than 2 to 3 meters tall, multi-branched, and the base of the stem is often lignified. Even pinnate compound leaves, leaf length 15 to 30 cm, leaflets 30 to 40 pairs, rectangular, petiole length 7 to 12 cm, phototropism, nocturnal leaflet closure. The inflorescence is axillary, with 3 to 6 flowers, yellow, and purple spots on the flag petals. The pods are slender, 15 to 25 cm long, prone to bursting when ripe, and have 20 to 35 seeds per pod. The seeds are round, bluish brown or yellow-green, weigh 13 to 16 grams, and the stratum corneum of the overripe seed coat is thickened, which is not easy to absorb water and becomes a duron.
Geographical distribution
It is mainly distributed in the tropical region of the eastern hemisphere; it is found in Guangdong, Hainan, Fujian, Zhejiang, Jiangsu and other places in China. It is mostly found in coastal alluvial areas.
Planting techniques
Tian Jing likes to be warm and wet, and the seeds can only germinate at 12 ° C. Growth is slow within 30 days after emergence, and then enters the rapid growth period, and under high temperature and humidity conditions, it can grow 3 to 5 cm per day. Strong flood resistance, if the water does not flood the top, it can still continue to grow. It is barren and salt tolerant, and can produce whole seedlings in soil with a total salt content of 0.3%, and soil with a total salt content of 0.5% can still grow normally. It is often used as a pioneer crop in newly reclaimed saline wasteland. In the double-cropping rice areas of southern China, seedlings can be first raised, and then planted in early rice fields or between rice rows as base fertilizer for late rice; dryland can be interplanted with medium-tillage crops such as sorghum and corn or replanted with wheat stubble; hilly wasteland or farmland gap land can be used as residual planting or cutting compost. A single species of field jing can produce more than 37.5 tons of fresh grass per hectare; it can be intercropped, set or replanted with other crops, and can produce about 15 tons of fresh grass per hectare. Fresh grass contains about 80% water, nitrogen 0.4 to 0.6%, phosphoric acid about 0.1%, potassium oxide 0.15 to 0.2%. Together with other feeds, cattle, sheep or beaten pulp can be fed to pigs. The seeds contain colloids that can be used in the petroleum industry, and the stems can be used for papermaking and stripping fibers.
Breaking of seeds hard - seed germination conditions
The seed coat of Tian Jing seeds has a waxy layer on the surface, the seed coat is leathery, it is not easy to be soaked by water, and the seed coat accounts for about 20% of the seed weight. The outermost layer is the epidermal layer, a palisade cell layer composed of a single column of columnary cells, and the cell wall has a thickening phenomenon. Therefore, the seeds are hard and solid, and the commonly used treatment methods are mechanical treatment (friction, cracking, etc.), temperature treatment (warm water at about 40 ° C), chemical treatment (concentrated sulfuric acid, nitric acid, hydrochloric acid, acetone, etc.). The test proved that concentrated sulfuric acid (98%) had the best treatment effect, with a germination rate of up to 83% and rapid germination, reaching 74% on the third day. It shows that tian jing seeds are resistant to concentrated sulfuric acid treatment. In practice, the treatment of 5 min should be used to save time. After the concentrated sulfuric acid treatment, be sure to rinse in running water. Otherwise, residual acid will affect the germination and growth of the seeds. Rinse under running water for about 2 hours.