The effect of nitrogen and sulphur fertilization on yield and quality of kohlrabi (Brassica oleracea, L.)

Abstract

SUMMARYIn a greenhouse pot experiment with kohlrabi, variety Luna, we explored the joint effect of N (0.6 g N per pot = 6 kg of soil) and S in the soil (25-35-45 mg kg -1 of S) on yields, on N, S and NO 3 -content in tubers and leaves, and on alterations in the amino acids concentration in the tubers. S fertilisation had no effect on tuber yields. The ranges of N content in tubers and leaves were narrow (between 1.42-1.48 % N and 1.21-1.35 % N, respectively) and the effect of S fertilisation was insignificant. S concentration in the tubers ranged between 0.59 and 0.64 % S. S fertilisation had a more pronounced effect on the S concentration in leaf tissues where it increased from 0.50 to 0.58 or to 0.76 % S under the applied dose. The NO 3 -content was higher in tubers than in leaves. Increasing the S level in the soil significantly reduced NO 3 -concentrations in the tubers by 42.2-53.6 % and in the leaves by 8.8-21.7 %. Increasing the S content in the soil reduced the concentration of cysteine + methionine by 16-28 %. The values of valine, tyrosine, aspartic acid and serine were constant. In the S 0 , S 1 , and S 2 treatments the levels of threonine, isoleucine, leucine, arginine, the sum of essential amino acids and alanine decreased from 37 to 9 %. The histidine concentration increased with increasing S fertilisation. S fertilisation of kohlrabi can be recommended to stabilize the yield and reduce the undesirable NO 3 -contained in the parts used for consumption.

Digestate from Biogas Plants is an Attractive Alternative to Mineral Fertilisation of Kohlrabi

“…The concentration of NO 3 -in plants is affected primarily by the vegetable species, level of N fertilisation, plant organ analysed, growth stage and the sulphur concentration in the tissues [36,37]. Kohlrabi is prone to a higher risk of nitrate accumulation in tissues than some other vegetables [31].…”

The effect of fertilisation with digestate on kohlrabi yields and quality

“…6: 274-278 Plant Soil Environ. doi: 10.17221/16/2016 is affected primarily by species-specific factors, level of N fertilisation, type of fertiliser, the plant organ in question, growth stage and the S concentration in the tissues (Marschner 2002, Lošák et al 2008. In both years (Table 5) the content of bulb nitrates (mg NO 3 -/kg FM) was significantly the lowest in the unfertilised control (135 and 163, respectively).…”

Effects of different nitrogen forms on the nutritional quality and physiological characteristics of Chinese chive seedlings

“…Two main nitrogen forms are used by plants in natural conditions: nitrite nitrogen (NO 3 --N) and ammonia nitrogen (NH 4 + -N) (Tschoep et al 2009). In addition to the amount supplied, the form of the available nitrogen has a significant effect on the growth, photosynthesis (Ali et al 2013), yield and quality (Lošák et al 2008) of plants. In general, most plants use NO 3 --N preferentially as an N source, whereas plant roots can absorb NH 4 + -N when soils are deficient in NO 3 --N. When NH 4 + -N is used as the only N source, most plant species show reduced growth, smaller leaves and a stunted root system on exposure to high NH 4 + -N concentrations and in severe cases, this leads to chlorosis.…”