Dārzeņu mēslošanas optimizēšanas iespējas | [Optimisation of vegetable fertilisation]

The yield of vegetables and their quality largely depends on their fertilization. Both economic and environmental aspects pose increasing challenges for vegetable producers in a series issues, including the balancing of fertilizer and yield. Everyone is clear — if we do not give any fertilizer, there will be no harvest. What to do? Last year, according to the Ministry of Agriculture order Institute of Horticulture has started research “Optimization of fertilization of widely grown in Latvia field vegetables for sustainable technology provision” (LAD No. 21-00-S0INV05-000023). Ten different sizes of vegetable growing farms from different regions involved in the study. They include both integrated and organic growers. During the research, in each farm from for separate vegetable fields three times soil samples are taken during the season. Spring and autumn the samples are fully analysed (organic substance content, pH, N, P2O5, K2O, Mg, Ca, B, S-SO4, Na, N-NH4+, N-NO3-) in the middle of summer only the nitrogen content is determined by focusing pay attention to its form — ammonium (NH4+) and of nitrate (NO3) for the content in the soil. These analyses are carried out SPPS Agrochemistry Laboratory. Plant samples are analysed by the Institute of Biology of University of Latvia in the mineral nutrition laboratory, determining N, P, K, Ca, Mg, S and B separately for the production part and for the unproductive part that remains in the field. Tables 1 and 2 show nutrient removal with onion harvest and average of all samples in 2021 (kg/t), in table 3, the balance of nutrients in the cabbage field in 2021 on the farm included in the trial, kg/ha and in table 4, the content of nutrients in the soil in the carrot fields in the spring of 2022 (mg/kg). The chart shows the dynamics of nitrogen forms in bio-carrot fields in 2021, kg/ha. Conclusions: (1) removal of nutrients with the crop there is no depends on the farming method, but depends on the growing conditions and cultivars, namely plant dry matter in the production part, as well as production parts and proportions of plant residues; (2) foliar fertilizers improve leaf quality, but does not directly affect the content of elements in the roots; (3) an important form of nitrogen fertilizer is: amides, NH4- or NO3+, (4) Ca : Mg ratio is important; (5) integrated cultivation of regular leaves juice analyses allow timely correction lack of certain nutrients with application of foliar fertilizers; (6) fertilization solutions should be sought for optimization in organic farms.