<h1 class = "pgc-h-arrow-right" >1 Biological characteristics of large and long taro yam</h1>
Yamato yam is a new variety of yam introduced from Japan around 2000, the plant is strong and disease-resistant, and the yam stem is round. The stem is right-handed, 3 to 5 m long; less branched, single-leaf, the lower leaves of the stem are alternate, the middle and upper leaves are opposite, and rarely rotate; the leaf length is about 6 cm, the width is about 6.2 cm, the petiole is 5.4 cm long, the two sides are smooth, no soft hairs, the surface is dark green, and the back is grayish white; the leaf edge is full margin or shallow wavy margin; the base is deep heart-shaped and broad-hearted; the leaf shape is changeable, the base leaf is heart-shaped, the middle and upper leaves are 3 Shallow lobes, mostly triangular halberd; the apex is gradually pointed to sharp; the leaf veins are 7, radial, and the reticular veins are obvious The basal vein has 2 to 3 branches. There are bead buds between the axils of the leaves, 1 to 2 at each place, initially round, cylindrical, round or irregular after maturity, gray-brown, the surface of the surface is vigorous and rooted when the weather is wet, and it becomes a tumor when mature. Hermaphroditic, cultivated male. At flowering, the male inflorescence is a spike-like inflorescence, 1 to 3 cm long, 2 to 11 are born in the leaf axils, and the flower color is pale yellow and the flowers are small. When the female flower is not expanded, the ovary is very similar to the shelled and immature rice grain, with a small rice grain-sized female flower at the apex, and the ovary is expanded into a triangular shape, and each edge is semicircular, so the result is triangular and nearly spherical.
<h1 class="pgc-h-arrow-right" >2 cultivation techniques</h1>
<h1 class="pgc-h-arrow-right" >2.1 site selection</h1>
Yamato yam cultivation mainly selects plots with high terrain, good drainage, no salinity, deep soil layer and low groundwater level. Choose sandy soil, sandy loam soil, loam planting, in recent years, local planting of yam in order to pursue high quality, also choose some clay planting. Heavy stubble planting should be avoided in the actual production process. It is best to choose plots that were grass crops in previous years to avoid yam nematode hazards.
<h1 class="pgc-h-arrow-right" >2.2 land preparation</h1>
Before deep ploughing, 50 to 100 kg of compound fertilizer (15:15:15), 3 000 to 5 000 kg of decomposed organic fertilizer or 500 kg of commercial organic fertilizer were applied per 667 m2, and 500 mL (40% active ingredient) of octylthion (40% of active ingredient) was mixed with bran for the control of underground pests. After fertilization, plough the land 30 cm deep, rake the ground and level it, and draw a line in the north-south direction. The line width is 1.4 to 1.5 m. According to the line, the yam trenching and ripping machine is used to ditch the loose soil, the depth of the ditch is 80 to 100 cm, and the width of the ditch is 70 cm.
<h1 class="pgc-h-arrow-right" >2.3 species selection</h1>
Strict seed potato screening is carried out before sowing, and seed potatoes or yam mouths of about 150 g of yam beans are selected as seed potatoes with bright color, full top buds, no disease and insect hazards, no rot, no frost, and good quality. Sow 20 d before sowing, cover seed potatoes at night or move into the warehouse. The key technology for seed selection is that the top buds are full, and seed potatoes without top buds are strictly prohibited, in order to produce seedlings quickly and seedlings together. Sprouts emerge about 15 d faster than those without buds.
<h1 class="pgc-h-arrow-right" >2.4 planting techniques</h1>
2.4.1 Sowing
Around March 20, the temperature began to rise, at this time you can first use large water to sink the ditch, after 5 to 6 d the soil surface is slightly dry, you can use the pastoral management machine to flatten the ridge, and then each ridge opens a double row, the two rows are 40 cm apart, the two rows of yam in the middle of the fertilization ditch, need to use (15:15:15) compound fertilizer 50 kg/667 m2. Each row of yam is 15 cm from the edge of the ditch, so as not to grow to the edge of the ditch and cause yam deformity. After that, the seed potatoes are placed at a plant spacing of 20 cm, so that the orientation of the yam seed potatoes is consistent, sprinkled with octylthion poison bait, and covered with 5 cm of soil. After planting, lay a drip irrigation belt or micro-spray belt between the two rows of yam in each ridge. Then spray evenly with 150 mL/667 m2 shitian make-up water. The spraying area of Shi Tian Patch is in the arch shed.
2.4.2 Arch building
We purchase a film with a thickness of 0.01 to 0.012 mm and a width of 1.5 m. Bamboo pieces with a length of 1.5 m and a width of 2 to 3 cm are set up with 1 arch every 1 m.
<h1 class="pgc-h-arrow-right" >2.5 field management</h1>
2.5.1 Peeling brackets
After the yam colonization and overburden, drip irrigation is carried out once, the second drip irrigation is made when the seedlings emerge around 20 days, and when the yam vine grows to 30 cm, the film is removed and the arch is removed, and a bamboo pole is inserted or a yam net frame is set up. In recent years, the yam grid rack due to low cost, simple operation, gradually accepted by farmers, the current Weifang area planted yam, yam grid utilization rate of more than 90%.
2.5.2 Water and fertilize
After the stent, take care to keep the soil moist near the roots of the yam. After entering June, the yam grows rapidly above and below ground, and the amount of water should be increased and attention should be paid to topdressing. Fertilization tanks are used when topdressing, and drip irrigation is used to achieve water and fertilizer integration. In early to mid-June, urea 15 kg/667 m2 was applied. From the end of June to the end of July, the instant compound fertilizer was applied in 8 times, 15 kg/667 m2 each time.
2.5.3 Weeding in medium tillage
Field herbicides have been sprayed at the time of planting, and weeds should be pulled out in time after that, but care should be taken not to damage the tuber and root system of the yam.
2.5.3 Pest control
After the yam emerges, the branches and leaves grow rapidly. Due to the low precipitation in the early stage and the light disease, a prophylactic fungicide of 80% daisen manganese zinc 1 000 times liquid can be used to prevent anthrax, spot blight and other diseases. Entering July, the local rainy season, the disease worsens, at this time the application of Fumei double, Bacillus, Carbendazim two two-two compound, spray 3 times can be. Leaf bees mainly bite the yam leaves, resulting in leaf loss and reduced yields, but the incidence is very low in general years, when it occurs with 2% enemy kill 3 000 times liquid or 90% crystalline enemy 1 000 liquid spray control.
<h1 class="pgc-h-arrow-right" >2.6 timely harvest</h1>
Yam harvesting generally begins on August 20. At this time, the weight of the yam is 90% of the late harvest, but the apex is still white, the quality is not as good as the yam harvested at the end of October, and it is very prone to browning. However, at this time, the price is high, the efficiency is good, and the peasants have a high enthusiasm.