We need agricultural chemicals to grow tea.
Crops are susceptible to diseases and pests, so agricultural chemicals are used in cultivation for a stable supply. Every crop has a different purpose for using them.
Agricultural chemicals that are used for tea
Agricultural chemicals that are used in tea cultivation are pesticides, fungicides, herbicide, etc.
Fungicides are divided into the two types: Protectants for disease protection and therapeutic agents for disease treatment.
The use of pesticides, regarding residue standards and the period and method of use, is strictly regulated by Agricultural Chemicals Regulation Act, Food Sanitation Act, Water Pollution Prevention Law, etc.
Diseases of tea
There are several diseases of tea. Infected parts can be fresh buds, leaves, roots, stems, or others depending on the case.
While different cultivars are liable to different diseases, common diseases are anthrax, blister blight, Pythium red blight, Dendrophoma obscurans, Pestalotiopsis longiseta, etc.
In particular, Anthrax can be seen at tea plantations across the country because “Yabukita,” the representative cultivar of Japanese tea, is susceptible to it. Agricultural chemicals are effective against these diseases to some extent.
Pests of tea
There are about 100 types of pests. There are so many, but only a dozen or so require control.
Major pests include yellow tea thrips, Kanzawa spider mites, tea jassids, tea leaf roller, and white peach scales. Pest damage varies by pest types. Some of them suck the sap of tea trees, and others eat leaves, especially fresh buds. There is also one that blights stems and branches.
Advantages and disadvantages of Agricultural chemicals
The advantages and disadvantages of Agricultural chemicals are as follows.
The basic disease prevention is to grow a disease-resistant cultivar, but it is unlikely that the chosen cultivar also makes large yields of good quality. To cover these shortcomings, farmers use agricultural chemicals.
In addition, increased weeds take necessary nutrients for the growth of tea trees, so they sprinkle herbicides to prevent the growth of weeds. It also reduces labor for farmers suffering continuous shortage of hands.
To fulfill the purposes of pesticides, such as killing pests and removing weeds, they need to be violently poisonous. It is not only consumers but also the farmers sprinkling them who worry about health hazards. Furthermore, the use of pesticides is disturbing the ecosystem by acting only on specific pests and weeds, and inevitably causing negative environmental effects. Today’s pesticides are friendlier to the human body and environment than before. However, there are still many challenges.