Detailed Explanation of High-Efficiency Cultivation Techniques for Shallow-Water Lotus with Straw

High-efficiency cultivation of shallow-water lotus with straw has developed quite rapidly in Feixian County, Shandong Province over the past five years. In 2005, 8,870 lotus ponds were built, covering an area of more than 5,300 mu. The reason is that this technique has obvious advantages over traditional shallow-water lotus cultivation. Mainly, it has high yield and good benefits. The average yield per mu of shallow-water lotus cultivated with this technique is 4,923 kg, which is 1,242 kg more than the 3,681 kg of ordinary cultivation, an increase rate of 31%, and the quality is good with a high marketable rate, with a net increase in income of more than 1,800 yuan per mu. Analysis shows there are three reasons for the high yield: first, the use of early-maturing, densely planted varieties; second, the straw releases heat, providing sufficient energy for the lotus; third, the carbon dioxide released by the straw is a raw material for photosynthesis, which is absorbed and utilized by the lotus. The second advantage is labor-saving harvesting. With ordinary shallow-water lotus, each person harvests less than 100 kg per day, while with straw shallow-water lotus, it is more than 400 kg, which is more than 4 times that of ordinary cultivation, greatly improving labor productivity. The third advantage is the high utilization rate of straw. Each mu of straw shallow-water lotus can consume 19-30 mu of crop straw, reducing the waste and environmental pollution caused by straw burning, turning waste into treasure, and meeting the requirements of ecological agriculture.

1.@#@185@#@Building the Pond

Site selection requirements. Low-lying land, river beach land, pond land, and abandoned land are all ideal sites for building ponds, as long as they have sufficient sunlight and are close to a water source. The plane shape of the lotus pond should preferably be rectangular or square, with an area generally of 0.5-1 mu. For a whole stretch of lotus ponds, planning should be done well, leaving walkways, inlet channels, and drainage ditches. According to different terrains, generally dig down 0.5 m for the lotus pond, and the completed lotus pond depth is 0.7-0.8 m. After the pond is built, the bottom should be leveled and tamped. The pond walls can be made of appropriately sized concrete edge slabs, or built with hollow bricks. The top of the wall should be 20 cm above the ground, and the pond wall should have a water inlet and a water outlet.

Pond hardening. On the basis of leveling and tamping, lay a layer of anti-seepage plastic film on the pond bottom, and smooth it with 1:3 cement-sand mortar to a thickness of 2-3 cm. The pond walls should be pointed with sand mortar or coated with a layer of sand mortar to prevent seepage and leakage. The top of the pond wall should be spread with a 2-3 cm layer of sand mortar and compacted with a trowel to facilitate field operations.

Laying straw. Straw selection. It is best to use a 1:1 mixture of gramineous and leguminous crop straw. If only gramineous crop straw is used, an additional 10-15 kg of nitrogen fertilizer should be applied per mu to prevent an imbalance in the carbon-to-nitrogen ratio during the decomposition of crop straw, which could cause microorganisms to compete with the lotus for nitrogen when decomposing the straw.

Straw treatment. Before the crop straw is put into the pond, first cut it into 10-15 cm segments, then carry out harmless treatment. You can spray with a 500-fold dilution of 50% carbendazim WP plus an 800-fold dilution of 50% phoxim, pile it into a large heap, cover with plastic film, and let it sit for 24 hours. Alternatively, after the straw is laid on the pond bottom, spray with the above agents, using no less than 100 kg of solution per mu.

Straw laying. The suitable thickness for laying straw is 20 cm. After the straw is put into the pond, rake it back and forth several times, trying to lay the straw horizontally with a uniform and flat surface.

Backfilling soil and fertilizer. For the backfill soil, try to choose mature soil, pick out bricks, tiles, stones, and other debris, with a thickness of about 20 cm. Then evenly spread 4,000-5,000 kg of fully decomposed farmyard manure and 150-200 kg of ternary compound fertilizer per mu, and shallow hoe several times to mix the soil and fertilizer evenly. Two days before planting, apply 50 kg of quicklime per mu, rake evenly to disinfect the soil, and prevent the organic acids produced during straw decomposition from adversely affecting the root growth and nutrient absorption of the lotus.

2. Selecting Fine Varieties

For shallow-water lotus, choose varieties with relatively small rhizomes and leaves, tolerance to shallow water, strong stress resistance, early maturity, and suitability for dense planting. Such as Thai lotus, white lotus, Elian No. 4, Elian No. 5, etc.

Reasonable dense planting. To ensure high yield, the seed lotus amount for straw shallow-water lotus planting should be 150-200 kg more per mu than conventional planting, that is, 400-500 kg of seed lotus per mu. The planting row spacing is 80 cm, plant spacing is 50 cm, and about 1,600 plants are planted per mu.

3. Planting

Planting time. It is better to plant when the daily average temperature reaches 15°C and the soil temperature at 10 cm depth is 10-12°C. In the Huanghuai region, it is generally from April 15 to 25. Planting should not be too early or too late. If too early, the soil temperature is low, and after planting, seedlings emerge very slowly, which can easily lead to seed rot or dead seedlings; if too late, although seedlings emerge quickly, the terminal buds are easily damaged during planting, and the growth and development period is shortened, which can easily cause reduced yield.

Seed lotus selection. Seed lotus is generally dug out just before planting. When digging, be careful to protect the terminal buds to ensure uniform emergence of the lotus. Select whole lotus with daughter lotus that conforms to the characteristics of this variety, with more than 2 nodes of fully mature rhizome, large rhizome, vigorous buds, no damage, no pests or diseases, and fresh parent rhizomes and daughter rhizomes. The digging of seed lotus should be based on the day's planting amount, digging and planting as you go. If it cannot be planted completely on the same day, sprinkle water, cover, and keep warm to prevent the lotus buds from withering.

Seed lotus treatment. Before planting, wash the seed lotus and soak it in a 500-fold dilution of 50% carbendazim WP or a 600-fold dilution of 70% chlorothalonil WP for 10-15 minutes for disinfection. Remove and let it dry slightly, then plant immediately.

Planting method. Begin planting lotus 60 cm from the pond wall. When planting, the lotus heads should all face inward. The positions of seed lotus between two rows should be arranged in a triangular staggered pattern. For whole lotus used as seed, one per hole; for daughter lotus, two per hole. Generally, the lotus head is buried 12-15 cm deep, and the rear node is slightly tilted above the water surface to use sunlight to raise temperature and promote sprouting. The lotus heads in the surrounding rows should all face inward to prevent the lotus runners from extending outside the pond. After planting, water promptly, with a water depth of 4-5 cm.

4. Field Management

Regulating water level. From planting until the appearance of three leaves, maintain a shallow water layer of 3-5 cm to help raise soil temperature and promote the sprouting and growth of lotus buds. With the growth of the plants and the formation of branches, the water layer should gradually be maintained at 7-12 cm. In the high-temperature summer period, maintain a deep water layer of 20-30 cm or