The latest course of High-yield cultivation techniques of spinach

Spinach belongs to Chenopodiaceae and belongs to 2012 herbs. Also known as red root vegetables, Persian food. Originally from Persia to Iran, it was introduced into China in the Tang Dynasty. It has a long history of cultivation and is widely planted in the north and south of our country. It has wide adaptability, strong cold tolerance, storage resistance, long supply period, easy to grow and harvest quickly, and high yield. the product can be supplied in early spring and off-season in autumn and winter. it is one of the important vegetables in autumn, winter and spring in north China. Spinach is green, tender and delicious, rich in nutrients and rich in vitamins and mineral elements. it is a kind of vegetable with high nutritional value.

Biological characteristics of spinach

1. Botanical characteristics

① root. Spinach has deeper taproots and is more developed. Taproot slightly thicker and slightly inflated, upper red, stored nutrients, sweet and edible. The main root groups are distributed in the plough layer of 25~30cm. The lateral root is not developed and is not suitable for transplanting.

② stem. The vegetative growth period is short stem, and the flower stem is elongated and high 66~100cm during reproductive growth.

③ flowers. The flowers of spinach are unisexual and a few have bisexual flowers. Dioecious, a few monoecious. Male flowers spikes, inserted in top of stem or leaf axils, apetalous, calyx 4-lobed, stamens as numerous as calyx. Anthers longitudinally lobed, many pollen, yellowish green, wind-pollinated flowers. Female flowers clustered in leaf axils, apetalous, with 1 pistil, stigma 4-6, calyx 2-4-lobed, enclosing ovary, ovary 1-loculed. There is one ovule in it. The calyx of spiny vegetables develops into horny protuberances. Sowing with "seed" is actually fruit. Female flowers are clustered in leaf axils, with 6-20 florets per axil. Without a flower stalk, or with a flower stalk of varying length.

④ leaves. Before bolting, the leaves of spinach were born on the shortened stems, and the roots came out of the leaves. There are two types of leaves: round leaves and pointed leaves. Round spinach leaves are large and fleshy, smooth, ovoid or facing; pointed spinach leaves are narrow and thin, hastate or arrow-shaped, apex acute or obtuse. Spinach has dark green leaves, soft texture and slender petiole, which is the main edible part.

⑤ fruits and seeds. The fruit of spinach is a utricle, irregularly round, with 1 seed in it, wrapped in a hard leathery exocarp. It is divided into two types: thorn and non-thorn. The endocarp is corked, the thick-walled cells are well developed, and the water and air are not easy to penetrate, so the seeds germinate slowly. The 1000-grain weight of seeds is 9.5-12.599. Under general storage conditions, the seeds can be preserved for 3-5 years, and the seeds with 2-year-old have strong germination ability.

2. Requirements for environmental conditions

① temperature. Spinach is a kind of vegetable with the strongest cold tolerance among green leafy vegetables. It can survive the winter in the open field in the south of the Yangtze River basin, and it can survive the winter safely in the open field in the area of-10 degrees. North China, Northeast China and Northwest China can survive the winter in the open field with wind barrier and ground cover. The cold tolerance of spinach is closely related to plant growth and development and seedling age. For the plants with 4-6 leaves, the persistent roots can withstand the short-term low temperature of-30 degrees, and only the outer leaves are frozen and yellowed at the low temperature of-40 degrees, but the roots and buds will not be harmed. If the seedlings have only 1 or 2 leaves, or the seedlings are too large, or the plants that are about to bolt, it is easy to die from freezing injury during overwintering. Spinach has a wide adaptability, the suitable temperature for growth is 15-30 degrees, the optimum temperature is 15-20 degrees, spinach seeds can germinate at 4 degrees, the optimum temperature is 15-20 degrees, 4 days can germinate, the germination rate is more than 90%. With the increase of temperature, the germination rate decreased.

② illumination. Although spinach is a low-temperature long-day crop. However, flower bud differentiation is mainly affected by the length of sunshine, which is easy to pass through the light stage under long sunshine and high temperature, and low temperature can promote flower bud differentiation under long sunshine. After flower bud differentiation, the temperature increased and the bolting and flowering accelerated when the sunshine was longer. When the overwintering spinach enters the following spring and summer, the plant will bolt and blossom quickly.

③ moisture. Spinach has the most vigorous growth, thick leaves, good quality and high yield under the environmental conditions of 80%-90% air humidity and 70%-80% soil moisture. Spinach needs a lot of water in the growth process, lack of water during the growth period, slow growth, aging mesophyll, increased fiber, prone to downy mildew, especially in high temperature, dry, long sunshine, will promote flower organ development and early bolting.

④ soil nutrition. Spinach has a wide adaptability to soil, and it is suitable to be planted in water conservation, fertilizer conservation, moist (night tide) fertile soil, pH 6: 7.5 neutral or slightly alkaline loam. Acidic soil will poison spinach and is not suitable for cultivation. Spinach fast-growing green leafy vegetables require more nitrogen fertilizer to promote leaf growth, good quality and high yield. Nitrogen fertilizer should be applied on the basis of total nitrogen, phosphorus and potassium fertilizer.

3. Growth and development

The vegetative growth period of ①. From spinach sowing and emergence to growing all the differentiated leaves, the inflorescence began to differentiate from cotyledons to the appearance of two true leaves, which grew slowly. After the two true leaves unfolded, the number, weight and surface of leaves. Growing rapidly at the same time. The number of leaves during inflorescence differentiation varied with variety, sowing date and climatic conditions, ranging from 5 to 6 leaves to more than 20 leaves.

The reproductive period of ②. From inflorescence differentiation to seed maturity, there is a period of overlap between the early stage and the vegetative growth period. The factors that can enhance photosynthesis and nutrition accumulation in external conditions can generally promote the female to strengthen, with more lateral branches, more flowers and full grains after bolting.

Types and varieties of spinach

According to the shape of spinach leaves and the presence or absence of thorns on the fruit, spinach can be divided into sharp leaves (prickly) and round leaves (no thorns).

① Beijing pointed leaf spinach. Beijing local varieties. The leaf is arrowhead-shaped, there are a pair of deep lobes at the base, the green is thinner to the meat, the fiber is less, the quality is better. The fruit is diamond-shaped and spiny. It is cold-resistant and heat-resistant, with a yield of 1000-2500 kg per mu, which is suitable for root stubble overwintering and autumn cultivation.

② Japanese big leaf spinach. Leaf blade elliptic to ovoid, apex slightly pointed, base shallowly notched. The leaves are broad and fleshy, thick green. Strong heat resistance, not cold-resistant, suitable for summer and autumn cultivation. High output and good quality.

③ round leaf spinach. Introduced from the United States, it is a thornless species. The leaf is oval to broad triangular, the leaf is hypertrophy, the leaf surface is wrinkled, and the color is dark green. Sweet and tender quality, late bolting in spring, high yield, good quality, but not cold-resistant, single plant weight 0.5 kg. The disadvantage is the weak ability to resist downy mildew and virus disease. It is cultivated in Northeast, North China and Northwest.