Effect of boron applications on boron concentration of the leaves under the harvest base of tea plant

Abstract

The part of the tea plant evaluated nutritionally and economically are the shoots. For the shoots to be nourished, essential nutrients must be present in soil and leaves under the shoots which serve as a kind of storage organs. However, boron is deficient in soil for its high active-acid level and precipitation in the Black Sea Region in Turkey and the plant due to its immobility. A two-year fixed field experiment was designed in the Arhavi district of Artvin/ Turkey to determine the effect of soil and foliar boron application on the concentration, mobilization, accumulation, and storage of boron in the leaves under the harvest base of the tea plant. Disodium Octaborate Tetrahydrate (DOT, Na₂B₈O₁₃.4H₂O, 20.8 % B) was used as a boron source and, four applications were conducted: S₀L₀, S₀L₁, S₁L₀, S₁L₁ (S: Soil application, 0 kg B ha^-1, and 4 kg B ha^-1; L: Foliar application, 0 mg B L^-1, and 400 mg B L^-1). As a result of the analysis, boron accumulation was determined mainly in the old leaves, and the concentration decreased toward the young leaves. Moreover, the boron concentration in the leaves under the harvest base gradually reduced toward the end of the harvest season. However, tea plants deprived of boron positively reacted to soil and foliar boron fertilization, and the boron concentration of the leaves under the shoots increased significantly and reached above the critical deficiency limit (> 30 mg kg^-1). The most successful application was S₁L₁, followed by S₁L₀ and S₀L₁, respectively.

Keywords:

• Boron distribution
• boron fertilization
• boron transport
• tea plant

Disclosure statement

The corresponding author states no conflict of interest on behalf of all authors.

Additional information

Funding

This study is a part of the Ph.D. thesis of the first author and was supported by the Ankara University Scientific Research Projects Coordination Unit (Project No: I4L0447005).