Technical Points for Cultivating Dictyophora indusiata with Soybean Shade

Traditional cultivation of Dictyophora indusiata used bamboo shavings as the raw material, and the yield was low (20-30 kg/mu). Starting in 2000, the country's first use of rice husks as the raw material for cultivation together with shade sheds raised the yield per mu to 120-150 kg, increasing the benefit by 4-5 times. Starting in 2001, cultivation with soybean shade was used, with a yield per mu of 100-150 kg, eliminating the need for shade sheds, saving 3-5 cubic meters of wood, and reducing costs by 600 yuan per mu. After a successful 1000-mu demonstration in 2004, it was vigorously promoted in Taining County, with more than 2000 mu planted each year, of which the output value reached 15.6 million yuan in 2005, showing significant economic benefits. The main technical measures for cultivating Dictyophora indusiata with soybean shade are as follows:

I. Field Selection

1. Location requirements: a semi-shaded, semi-sunny location with convenient drainage and irrigation.

2. Soil requirements: fertile, loose soil that is not prone to compaction and has good aggregate structure, slightly acidic loam.

3. Field requirements: cultivation fields where Dictyophora indusiata has not been planted in the past 3-4 years, and fields where it has not been planted in the several plots upstream in the previous year.

II. Bed Preparation

7-15 days before sowing, remove weeds and debris, plow and turn the soil, sun-bleach for several days, then prepare the beds. The bed surface is 30 cm wide at the top, 70 cm wide at the bottom, 45-50 cm high, with a ditch width of 25-30 cm, and the length depends on the field.

III. Substrate Preparation

Rice husks can be prepared year-round. Use 100% rice husks for cultivation. At sowing time, soak the rice husks with water until thoroughly wet, with a moisture content of 65%-75%.

IV. Spawn Selection

1. Strain selection: Dictyophora indusiata D You No. 42.

2. Spawn requirements: white mycelium, thick and fascicled mycelium, dense aerial mycelium, spawn age 60-70 days.

V. Sowing

1. Sowing period: any time from February to May; generally sowing begins after the 15th day of the first lunar month.

2. Method: use layer sowing. Open a ditch from the bed surface, 10 cm wide and 15 cm deep. First spread a 5 cm thick layer of rice husks on the ditch bottom; then sow a layer of spawn (generally 700 bags of spawn per mu), cover with a 10 cm thick layer of rice husks, and cover with 3-5 cm of soil. After sowing, cover the bed surface with about 2 cm of straw for insulation, moisture retention, and weed control.

3. Soybean interplanting: at sowing time, sow after Awakening of Insects. Interplanting can be done by direct hill sowing on the Dictyophora indusiata bed surface. For spring soybean, the single-row hill sowing spacing is 25-30 cm; for soybean, the hill sowing spacing is 20-25 cm.

VI. Management

1. Temperature: follow natural conditions.

2. Moisture: generally follow natural conditions. (1) After a continuous week of sunny days, appropriate watering may be done to retain moisture; (2) in drought years, flush water may be run through and left to soak for 13 hours; (3) drain waterlogging promptly. Before the rainy season arrives, dig drainage ditches around the cultivation site. The drainage ditches should be more than 30 cm deeper than the bed ditches, and water should be drained promptly to avoid anaerobic fermentation caused by excessively high moisture content at the bottom of the substrate bed, which would cause the substrate to turn black.

Mycelial growth: after sowing, the spawn fills the substrate in 35-40 days, then after another 15 days the mycelial strands reach physiological maturity and climb onto the casing soil, then after another 15-20 days the fruiting bodies form. From the appearance of the fruiting bodies until the fruiting body forms and is ready for harvest takes about another 30 days, so harvesting generally begins in late May to early June.

VII. Harvesting

Harvest promptly when the indusium of Dictyophora indusiata reaches its maximum expansion. When harvesting, it is best to use a small knife to cut the mycelial strands at the base of the volva. To improve product quality, it may be harvested before the indusium of the fruiting body spreads. Immediately use a small knife to cut off 2-3 mm from the top of the cap, then gently make a longitudinal cut on the cap, peel off the dirty green tissue on the cap, discard the volva, place it in a bamboo basket and bring it back. After the indusium spreads normally, place it on a bamboo sieve lined with gauze and dry it with forced air.