Relationship between tea (camellia sinensis) leaf uptake of major nutrients, Nitrogen, Phosphorous and Potassium (NPK) and leaf anatomy of different varieties grown in the Kenyan highlands

Abstract

Uptake of major nutrients (NPK) through the leaf st udies were carried out on three varieties of tea gr own in the Kenyan Highlands. A foliar fertilizers trial was se tup in three sites comprising of 36 plots per site in the major tea growing regions in Kenya. The uptake of NPK through leaf ti ssue and the role of leaf anatomy were investigated . Two foliar fertilizers tested were Foliar Fertilizer 1 (FF1) a nd Foliar Fertilizer 2 (FF2), a positive control of Soil Fertilizer (SF) and a blank were used to standardize the method. Le af anatomical studies were done by determining the stomata count of the third leaf of sample plants from each plot in a ll the trial sites. Results showed significant corr elation between stomata count and first mature leaf nutrients; N (r=0.387, p ≤ 0.05), P (r=0.32, p ≤ 0.01) and K% (r=-0.014, p ≤ 0.01). Tea yields were found to correlate significantly with NPK nutrient uptake; N% r=0.453 (p ≤ 0.01), P% r=-0.332, p ≤ 0.01 and K% r=-0.373, p ≤ 0.05. Stomatal patterns and density responded to th e environment, where Kericho site (west of Rift Val ley) had significantly higher stomata count than Kirinya ga and Meru sites both in east of Rift valley at HS D= 6.5, 5.6 at p ≤ 0.05 respectively. Overall the leaf anatomy, i.e. epidermal layers (<50μm thick), palisade layers (50μm thick) and mesophyll layers (150-200μm) were not affected by fertilizer application