Shallot Plant
Shallots (Allium ascalonicum L.) are included in the family Liliaceae and are annual vegetable crops, short-lived and propagated either vegetatively using tubers or generatively by seeds (TSS=True Shallot Seed).
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| In general, shallots are consumed every day as a cooking spice, and can also be used as traditional medicine to reduce the fever of sick people. |
Shallot Growing Requirements
Shallots are suitable for growing in the lowlands to highlands at an altitude of 0-1000 m above sea level. The optimum height for the growth and development of shallots is 0 - 450 m above sea level.
Onion plants are sensitive to rainfall and high rainfall intensity, as well as foggy weather. This plant requires maximum sunlight (minimum 70% radiation), air temperature 25-32 0 C, and relative humidity 50-70%.
Shallots require soil with a crumb structure, medium to clay texture, good drainage and aeration, sufficient organic matter, and a neutral soil pH (5.6–6.5). The most suitable soil for onion plants is Alluvial soil or its combination with Glei-Humus or Latosol soil. Soil that is moist enough with water that does not stagnate is preferred by shallot plants.
A good time for planting shallots is in the dry season with sufficient water availability, namely in April/May after rice and in July/August. The planting of shallots in the dry season is usually carried out on former rice fields or sugar cane, while planting in the rainy season is carried out on dry land. Shallots can be planted intercropping with red chili plants.
Cultivation
1. Seeds
The recommended varieties are Yellow, Kramat–1 and Kramat–2. In general, shallots are propagated by using bulbs as seeds.
The need for seed tubers ranges from 800-1500 kg per hectare. The quality of seed tubers is one of the factors that determine the high and low yields of shallot production.
Good bulbs for seeds must come from plants that are quite old, which is about 60-90 days after planting (depending on the variety). Bulbs should be of medium size (5-10 g). The appearance of seed tubers must be fresh and healthy, pithy (solid, not wrinkled), and bright in color (not dull).
Seedling bulbs are ready to be planted when they have been stored for 2–4 months from harvest, and the shoots have reached the end of the tuber. A good way to store seed tubers is to store them in the form of bonds on a kitchen stove or stored in a special warehouse by smoking.
2. Land Preparation
On dry land, the soil is plowed or hoeed as deep as 20-30 cm, then made beds with a width of 1 - 1.2 m, a height of 25 cm, while the length depends on the condition of the land. On ex-paddy fields or former sugarcane, the soil is made beds first with a width of 1.75 cm, a trench depth of 50–60 cm with a trench width of 40–50 cm and the length is adjusted to the conditions of the land.
The condition of the beds followed the East-West direction. The treated soil is left to dry and then processed again 2-3 times until it is loose before repairing the beds neatly.
The time required starting from making the trench, plowing the soil (say 1, revealing 2, cocrok) until the soil becomes loose and ready for planting is 3-4 weeks. The remaining rice/sugar cane can be used as a growing medium for Fusarium sp, so it must be cleaned.
When cultivating soil, especially on acidic land with a pH of less than 5.6, it is recommended to give Kaptan/Dolomite at least 2 weeks before planting at a dose of 1–1.5 tons/ha/year which is considered sufficient for the next two growing seasons. Kaptan / Dolomite spread on the soil surface and then stirred evenly.
The provision of Dolomite is important to increase the availability of calcium (Ca) and Magnesium (Mg) nutrients, especially on acid lands or areas that are intensively cultivated for vegetable crops. For intensively managed land, the application of Dolomite as much as 1.5 tons/ha can increase the wet weight and dry weight of shallots.
3. Planting and Fertilizing
a. Cultivation of shallots in dry land/ moor
Fertilization consists of basic fertilizer and supplementary fertilizer. The basic fertilizers are cow manure (15-20 tons/ha) or chicken manure (5-6 tons/ha) or compost (2.5-5 tons/ha) and TSP-made fertilizers (120-200 kg/ha).
This basic fertilizer is given by spreading and stirring evenly with the soil one to three days before planting. Meanwhile, secondary fertilizers are Urea (150-200 kg/ha), ZA (300-500 kg/ha) and KCl (150-200 kg/ha).
The first follow-up fertilization was carried out at the age of 10-15 days after planting and the second follow-up at the age of 1 month after planting, each dose. Seedlings that are ready for planting are dirompes, cutting the tips of the seeds only if the shallot seeds are not ready to be properly planted (80% growth of shoots in tubers).
The purpose of cutting seed tubers is to break the dormancy period and accelerate the growth of plant shoots.
b. Planting shallots in paddy fields (former rice)
Fertilization consists of basic fertilizer and supplementary fertilizer. Basic fertilizer in the form of artificial TSP fertilizer (90 kg P2O5/ha) is spread and mixed evenly with the soil one to three days before planting.
Follow-up fertilizer in the form of 180 kg N/ha (½ N Urea + N ZA) and K2O (50-100 kg/ha). The first follow-up fertilization is carried out at the age of 10-15 days after planting and the second follow-up at the age of 1 month after planting. 80%).
The purpose of cutting seed tubers is to break the dormancy period and accelerate the growth of plant shoots.
4. Maintenance
Although the onion plant does not like a lot of rain, this plant requires sufficient water during its growth through watering. Planting on former rice fields requires adequate watering in the hot sun.
In the dry season, it is usually watered once a day in the morning or evening from planting until the age of harvest. Watering carried out in the rainy season is only intended to rinse the plant leaves, from the soil attached to the shallot leaves.
In the critical period shallots due to lack of water occurs during the formation of tubers, so it can reduce production. To overcome this problem, it is necessary to regulate the level of the ground water level (especially on former rice fields) and the frequency of giving water to shallot plants.
Weed growth in young shallots up to 2 weeks of age is very fast. Therefore weeding is a must and very effective to reduce competition with weeds.
5. Control of Plant Pest Organisms (OPT)
Thirteen types of pests and diseases are known to attack shallot plants, including Liriomyza chinensis, Thrips tabaci, Alternaria porii, Fusarium sp., anthracnose and others. Yield loss due to pest attack is about 26–32%. Control using Integrated Pest Control Technology (IPM), namely:
- Control in technical culture, including balanced fertilization, use of pest resistant varieties, and use of natural enemies (parasitoids, predators and insect pathogens).
- Mechanical control, namely by turning or cutting sick leaves or there are groups of Spodoptera exigua eggs, and the use of mosquito nets, the use of various types of traps (sex pheromones, yellow traps, light traps, etc.).
- Use of biopesticides.
- Selective pesticide use based on control threshold. Control with pesticides must be carried out properly, both in choosing the type, dose, spray volume, application method, interval and time of application.
6. Harvest and Postharvest
Shallots can be harvested after they are quite old, usually at the age of 60–70 days. Shallots were harvested after showing signs of 60% soft stem necks, fallen plants and yellowing leaves.
Dry tuber production reaches 6-25 tons/ha. Harvesting should be carried out in dry soil conditions and sunny weather to prevent tuber rot disease in the warehouse.
Shallots that have been harvested are then tied to the stem for easy handling. Furthermore, the bulbs are dried in the sun until quite dry (1-2 weeks) using direct sunlight, followed by grouping based on the quality of the tubers.
Drying can also be done with a special dryer (oven) until it reaches a moisture content of approximately 80%. If not sold immediately, shallot bulbs are stored by hanging shallot bundles in a special warehouse, at a temperature of 25-30ºC and a fairly low humidity (±60-80%).