Assessing the Response of Tomato Yield, Fruit Composition, Nitrogen Absorption, and Soil Nitrogen Fractions to Different Fertilization Management Strategies in the Greenhouse

Abstract

<jats:p>A greenhouse field experiment involving tomato (<jats:italic>Solanum lycopersicum</jats:italic>) was performed using different nitrogen (N) management regimes: sole application of differing rates of chemical N fertilizer (SC) (SC treatments: N0, N1, N2, and N3) and combined application of manure and chemical N fertilizer (MC) (MC treatments: MN0, MN1, MN2, and MN3). These were used to understand the relationship between comprehensive fruit composition, yield, and N fractions (soil mineral N; soil soluble organic N; soil microbial biomass N, and soil fixed ammonium) under greenhouse conditions. The results showed that the MC treatments significantly increased vitamin C and soluble sugar content compared with SC treatments. In addition, the MN2 treatment produced a high yield and had a positive effect on fruit composition. The N3 (563 kg N/ha) and MN3 (796 kg N/ha) treatments resulted in a high loss of N below the root zone (0–30 cm), consequently reducing N use efficiency. Soil mineral N, soil soluble organic N, and soil fixed ammonium tended to be higher during the first fruiting period, whereas soil microbial biomass N tended to be higher during the second fruiting period. MC treatments significantly increased the N fraction in the 0- to 30-cm soil layer; N fractions tended to be higher with the MN2 treatment. According to an optimum regression equation, soil fixed ammonium during the first fruiting period and soil microbial biomass N during the second fruiting period had a more significant influence on tomato yield and fruit composition. Overall, application MC at an appropriate rate (MN2: 608 kg N/ha) is a promising approach to achieving high yields and optimum taste, and it offers a more sustainable fertilizer management strategy compared with chemical N fertilization.</jats:p>

Opportunities of Reduced Nitrogen Supply for Productivity, Taste, Valuable Compounds and Storage Life of Cocktail Tomato

“…Overall, there were very small effects of the reduced N supply on tomato fruit yield and quality. Even the N content of the fruits (Table 4) was not affected by the N supply, in the same way as the other mineral elements (Table 4), which is in accordance with other studies with a comparable or even more severe N reduction than in our experiment [26,29,40,42,[53][54][55]. As proposed by Stefanelli et al [3], reduced N contents in plants would be expected if the N supply to plants was low.…”

“…In order to achieve environmentally sound fertilization while maintaining yield and quality, this experiment examined for tomato crops, cultivated in soil in a greenhouse, whether this balance could be achieved by reducing the N supply by 50% at the onset of fruit ripening. In fact, the total yield of fruits of the cocktail tomato varieties 'Delioso' and 'Apresa' (Table 2) was not reduced, being in accordance with studies using similar N levels for soil-grown tomato plants to our experiment (210 vs. 360 kg N ha −1 ) [20,[26][27][28][29][30].…”

“…In fact, Hartz and Bottoms [28] stated that a "seasonal N rate of 200 kg ha −1 appeared adequate to maximize fruit yield", which is supported by various studies of tomatoes [29,34,41,48,56,59]. Moreover, Zotarelli et al [27] proposed that N application rates above 176 kg ha −1 are not beneficial for tomato fruit yields but increase the leaching of nitrate.…”

“…They showed higher TEAC values probably due to the higher contents of ascorbic acid (Table 5). Other studies showed that reductions in the N supply up to one third of the optimal level often had no effect on the vitamin C content of the tomato fruits [2,7,15,20,29,32]. Moreover, other results suggest that the antioxidative capacity of tomato fruits is little affected by the N supply [20,50,51].…”

Tomato leaves under stress: A comparison of stress response to mild abiotic stress between a cultivated and a wild tomato species

“…On the other hand, insufficient nitrogen supply when applied during the vegetative state was shown to not affect the plant height and thereby the plant growth and yield of tomato in general (Han et al, 2014). Furthermore, only little effects are described for insufficient nitrogen supply (50 % reduction) applied during onset of fruit ripening, which were line-specific, and only slightly reducing the absolute amounts of fruits but increasing the relative amounts of marketable fruits, while chemical content, concentration of secondary metabolites, flavour and taste were not affected (Hartz and Bottoms, 2009; Zotarelli et al, 2009; Duan et al, 2019; Schmidt and Zinkernagel, 2021). Nevertheless, reduction of nitrogen supply to 15-35 % of optimal conditions may result in up to 30 % lower yields due to lower fruit weight (Wang et al, 2015; Qu et al, 2020).…”