How Many Jin Per Mu Does Grafted Cucumber Usually Yield, and the Best Rootstocks and Step-by-Step Seedling Raising Method
Cucumber, also known as hu gua, ci gua, wang gua, qin gua, qing gua, tang gua and diao gua, is widely cultivated throughout China, and many regions grow it in greenhouses or plastic tunnels. So how many jin per mu does grafted cucumber yield? What is best to graft with? How do you graft? What are the cucumber seedling raising methods? According to cucumber grower Mr. He, cucumbers grown in southern greenhouses can generally be grown for two seasons, though many grafted cucumbers are grown for just one season a year. For two seasons: in spring, seedlings are raised in early February, transplanted at the end of February or early March, cucumbers come to market in early to mid-April, and the vines are pulled at the end of June; in autumn, planting runs from mid-July to pulling the vines in mid-November. Spring yield is generally around 15,000 jin per mu, and autumn yield is generally around 12,000 jin per mu.
What is best to graft cucumber with?
1. The main rootstock varieties used for grafting cucumber include black-seeded squash, wax gourd, and the squash varieties Xintuzuo and Baijuzuo.
2. Cucumber grafting technology is a key technical measure in cucumber production and cultivation for overcoming continuous cropping obstacles, improving plant stress resistance, controlling diseases such as cucumber fusarium wilt and phytophthora blight, and achieving high yields. Grafted cucumbers have enhanced stress resistance and are tolerant of low temperatures, high temperatures, waterlogging and drought. Grafted seedlings have well-developed root systems, strong growth vigor, normal lateral branch development, stable fruit set, and can be grown in successive crops. Using grafting technology in field cucumber production can achieve many advantages such as increasing yield, preventing disease and improving the cucumber's own stress resistance.
How do you graft cucumber?
Cucumber grafting methods include the insert grafting method, approach grafting method, cleft grafting method, splice grafting method and so on. The approach grafting method and insert grafting method are the most commonly used because they are simple to perform and give a high survival rate.
1. Insert grafting method:
1. Oblique insertion method: Hold the rootstock hypocotyl between thumb and index finger, use a blade or the edge of a bamboo skewer to remove the growing point and both axillary buds, then use the bamboo skewer to insert obliquely on the top surface of the seedling stem, close to the inner side of one cotyledon base, at an angle of 30 to 45 degrees to the stem, toward below the other cotyledon, with an insertion depth of about 5mm, so that the bamboo skewer pierces the rootstock epidermis but does not break through; do not pull out the bamboo skewer yet.
Cut the cucumber seedling about 1cm below the cotyledons at an approximately 30° oblique angle (on the side where the cotyledons are attached); the first cut should be slightly flat but not cut through, then turn the seedling stem over and make another oblique cut from the back side, with a cut length of 0.5 to 0.7mm, shaping the scion into a wedge. Immediately pull out the bamboo skewer from the rootstock and insert the scion into the oblique insertion hole in the squash. Make the two cuts of the rootstock and scion fit together, with the cucumber cotyledons and squash cotyledons forming a cross shape, then secure with a grafting clip or wrap with plastic tape.
2. Vertical insertion method: Use a blade or the edge of a bamboo skewer to remove the growing point and both axillary buds of the rootstock, then at the center of the growing point use a bamboo skewer slightly thicker than the cucumber stem (homemade, the same thickness as the scion hypocotyl) to insert vertically about 0.5cm, and do not pull it out yet. Cut the cucumber seedling 1 to 1.5cm below the growing point at a 30° angle, forming an oval cut surface 0.4 to 0.5cm long, pull out the bamboo skewer from the rootstock, insert into the insertion hole in the squash stem, with the cotyledon directions of the rootstock and scion forming a “cross” shape. After spraying with clean water, place in a moisture-retaining small arched shed. Keep humidity at 95% for 3 days after grafting, with daytime temperature 25 to 28℃ and nighttime 18 to 20℃. After 4 days, ventilate slightly; after 8 days, the film can be removed for hardening off. After about 25 days, when the three-leaf-one-heart stage is reached, it can be transplanted.
2. Approach grafting method:
1. Rootstock: Use a blade or the edge of a bamboo skewer to remove the growing point and both axillary buds. On the hypocotyl 0.5 to 1cm from the cotyledon node, cut downward with the blade at an angle of 30 to 40 degrees to the stem, to 1/2 of the stem, at most no more than 2/3, with a cut length of 0.5 to 0.7cm (no more than 1cm). The cut depth must be strictly controlled: too deep and it breaks easily, too shallow and the survival rate drops.
2. Scion: At 1 to 2cm below the cotyledon node, cut upward from bottom to top at a 30 degree angle to 1/2 the depth of the stem, with a cut length of 0.6 to 0.8cm (do not cut through the seedling and keep the roots), and the cut length should equal that of the rootstock cut (no more than 1cm).
After treating the rootstock and scion, hold the rootstock in one hand and the scion in the other, insert the tongue-shaped wedge of the scion into the cut in the rootstock, then clamp the joint with a grafting clip or wrap it with plastic strip, and cover the scion roots with soil; after about 20 days, cut off the base of the scion.
3. Advantages and disadvantages of the methods
In production, these two grafting methods each have advantages and disadvantages, mainly analyzed as follows:
1. Insert grafting method: The insert grafting method removes the roots of the cucumber scion and inserts it obliquely into the growing point at the top of the squash rootstock. With insert grafting, the scion is positioned relatively high, far from the ground, so it is not easy for adventitious roots to form and cause the graft to lose its purpose of disease and cold prevention; moreover, the scion and rootstock join firmly, the scion does not easily fall off, and the rootstock does not easily break at the joint. However, because the scion has no roots when grafted by the insert method, it easily suffers water loss and wilting, reducing the survival rate. Therefore the insert grafting method has high requirements for grafting technique and management. It is not suitable for beginners to promote.
2. Approach grafting method: The approach grafting method takes the rooted cucumber scion seedling and the squash rootstock seedling, makes oblique cuts in the middle-upper part of the seedlings, and fits them together. Approach grafting is grafting with roots, so it does not easily suffer water loss and wilting and has a higher survival rate; therefore management requirements after grafting are less strict and it is easy to promote. However, because the joining position of the scion and rootstock is relatively low, it is susceptible to soil contamination and prone to producing adventitious roots, losing the purpose of disease prevention, cold prevention and yield increase; moreover, the scion and rootstock easily break at the joint, easily causing seedling injury and death; and after the scion survives, the roots must still be cut, which takes more labor.
Appendix: Cucumber seedling raising method
Variety selection: Choose early-maturing, disease-resistant, high-quality varieties such as Changchun Mici, Jinza No. 2, Jinchun No. 2, etc.
1. Seedling period: Raise seedlings in a greenhouse in early February.
2. Preparation of nutrient soil: The ratio is decomposed organic fertilizer : garden soil : fine furnace ash = 5:4:1. Add 0.5 kg of urea and 1-2 kg of diammonium phosphate per cubic meter of nutrient soil and mix evenly.
3. Seed soaking and sprouting: Soak the seeds for 4-6 hours, then place at 25-30℃ to sprout; sprouts can appear in 1-2 days.
4. Sowing: Can be sown directly in nutrient pots or sown in a seedbed. After sowing, maintain daytime 25-30℃ and nighttime 18-20℃; after emergence, maintain daytime 25-30℃ and nighttime 12-16℃. Seedling age is about 40 days.
5. Standards for strong seedlings: Plant height 15-18 cm, 5-6 true leaves, deep green leaf color, spreading growing tip, stem diameter 1 cm, short internodes, terminal flowers with buds.