Tea industry cultivation
Tea is an important cash crop and export product. 5 million kg of tea is exported every year to meet the domestic demand of Bangladesh. Tea cultivation in the country started in the early nineteenth century. The first tea garden was established in Chittagong in 1840 AD. Then in 1857 a tea garden was opened commercially at Malnichhara in Sylhet. At present the greater Sylhet area and the other Halda Valley Chittagong area are tea production centers. Tea cultivation has recently started in the Panchagarh area in the north-western part of Karatoya Valley. 57 thousand million kg of tea is being produced every year in 53 thousand hectares of land of 16 tea gardens in the country.
Favorable environment for tea
Tea trees prefer a somewhat forest environment in its growth. Warm and humid environments where the temperature is 26 to 28 degrees Celsius and rainfall is above 2000 mm and the amount of water vapor in the air is high i.e. humidity is 80-90%. In addition, the durability of daylight should be close to 12 hours and the soil should be acidic (pH 4.5-5.8), sandy loam and satisfactory nutritious. Tea trees cannot tolerate waterlogging at all. Tea seeds should be collected from the gutibari and planted in the seedbed in a triangular distance of 20 cm to 20 cm. Nursery soil should be kept nematode free before planting seeds or cuttings. Seedbed must provide shade. Each bed should be shaded with a bamboo mat at a height of 60 to 75 cm. Chemical fertilizers (urea, TSP and MOP) can be applied in the ratio of 2: 1: 2 for growth and vitality of nursery seedlings. In the cutting nursery, shade should be provided at a height of 150 to 160 cm with a bamboo stick. The nursery should be irrigated regularly.
Cultivation method
In Bangladesh, 55 to 60 percent of tea is cultivable. Tea is cultivated by contour method in hilly or hilly lands. The land has to be prepared by cultivating and ladders on high flat lands and clearing weeds. Pre-monsoon tea seedlings are best planted in April-May. However, if irrigation can be ensured, the seedlings can be planted from December to March. The planting distance in single row system is 60 cm to 90 cm i.e. 17 thousand 517 trees per hectare and in plain land distance is 80 cm to 105 cm i.e. 15 thousand 56 trees per hectare. The planting distance in double row method is 60 cm to 105 cm i.e. 19 thousand 960 trees per hectare. Healthy vigorous seedlings should be planted at a depth of 30-35 cm for clone seedlings and 40 to 45 cm depth for seed seedlings and 25 to 30 cm width for both. The first 23 cm of the hole. The soil should be kept on one side of the hole and mixed with 2 kg of decomposed dung manure, 30 g TSP and 15 g MP for each hole. The soil mixed with fertilizer should be given under the hole. To conserve soil moisture, mulch should be spread 8 to 10 cm away from the roots of the seedlings and 8 to 10 cm high after planting in the dry season. Water hyacinth, Guatemala or citronella grass, and even shrubs can be used as mulch. As the tea seedlings grow, NPK should be applied to the compound per plant.
Tea insects
Insecticides, insects and worms are some of the barriers to tea production. So far, 25 species of insects, 4 species of spiders and 10 species of worms have been identified in Bangladesh. Among them, tea mosquitoes, wasps and red spiders in the cultivable area and aphids, jessids, thrips, flashworms and worms are known as the main pests in nursery and immature tea plantations. These pests cause an average of about 15% of the annual damage. In some cases 100% loss is encountered.
The following is a brief introduction to these harmful insects in tea and their control measures.
1. Tea mosquitoes
Tea mosquitoes are an important pest. This is known as T-helopelitis. The nymphs and adult insects of this sucking insect absorb the young tips and leaf sap of the tea and the affected part turns black. Massive attacks stopped the growth of new leaves. In order to control this pest of tea, Malathion 57 EC should be mixed in 500 liters of water at the rate of 2.25 liters per hectare in dry season and sprayed every 7 days.
2. Red spider
The red spider of tea is very harmful. Very small in size. Mature leaves attack from above and below. Absorption of sap results in copper on both sides of the leaf and makes it look dry and faded. As a precautionary measure, sulfur 60 WP at the rate of 2.25 kg per hectare should be mixed in 1000 liters of water and sprayed every 5-6 days.
3. Termites
Termites are social insects like bees. The tea garden is known as 'Ulupoka'. It is one of the main pests of tea. Tea eats the dead or rotten part of the tree. They live in mounds on the ground and in tree trunks. Only the working class eats tea. Insect repellent should be sprayed at the base of the plant by mixing Admire 200 SL 1000 at the rate of 1.5 liters per hectare or Darsban 20 EC at the rate of 10 liters per 1000 liters o
4. Jesse
One of the harmful pests of nursery and immature tea. Thyodan 35 EC at the rate of 1.5 liters per hectare or Ripcord 10 EC at the rate of 500 ml 500 liters per hectare. Mix in water and spray every 7 days. Spray under young tips and young leaves.
5. Aphids
They are also called jabpoka. One of the harmful pests of nursery and immature tea. 1.5 liters per hectare. The rate of thiodan 35 EC or 500 ml. Ripcord 10 EC 500 l rate. Mix in water and spray every 7 days.
. Thrips
Thrips are tiny brown insects. One of the harmful pests of nursery and immature tea. To control this pest, apply thiodan 35 EC or 500 ml at the rate of 1.5 liters per hectare. Ripcord 10 EC 500 l rate. Mix in water and spray twice every 7 days.
. Urchunga
Urchunga is a big problem in nursery and immature tea cultivation. The face has hard and sharp teeth. The front legs are grooved, like a flat spade. Due to this condition of the feet, small tea-seedlings are easily cut off. These are nocturnal insects. Holes in the ground and comes out after dusk. To control this, the urchunga holes in the nursery and immature tea plantation area should be identified and water should be poured into a thin tube with two teaspoons of burnt mobil in the mouth of the hole. When the urchunga comes out of the hole, it should be killed with a stick or a foot injury.
. Worms
They live on the ground. Microscopic and microscopic insects. Yarn or semai shaped in appearance. Absorbs the juice of young roots. As a result git is formed. The attack makes the seedlings weak and sick and hinders the growth of the seedlings. In order to control this insect, it is better to apply Furadan 5 g 185 g per 1 cubic meter of soil
To date, 22 different bacterial diseases have been identified. The main diseases of tea and their suppression business are discussed below.
A. The affected part of the soft tip and young leaves become swollen and form foscar. In order to control this disease, Champion 6WP 2.24 kg or Kalingin 60 EC 1.12 liters per hectare should be mixed in 1120 liters of water and sprayed on the leaves.
B. In nursery and arable areas, the affected part of the soft tip and young leaves turn black and gradually die from top to bottom. In order to control this disease, Champion 6WP at the rate of 2.24 kg or Cupravit 50 WP at the rate of 2.6 kg or Kalingin 60 EC at the rate of 1.12 liters per hectare should be mixed with 1120 liters of water and sprayed on the leaves.
C. The disease is caused by the attack of one species of algae on the stems and old branches. Although the stem is affected, the symptoms of the disease appear on the leaves. The leaves are yellow. In order to control this disease, Macuprong 18 W 2.24 kg should be mixed in 1120 liters of water per hectare and sprayed on the affected stems.
The contribution of tea to the country's economy is undeniable. It is possible to earn more by exporting domestic tea abroad.