Application of Controlled-release Fertilizer to Forcing Culture of Tomato Using Root-proof Capillary Wick

Abstract

Root-proof capillary wick culture is expected to eliminate water drainage. Application of controlled release fertilizer instead of liquid fertilizer may be economical because liquid fertilizer equipment would not be required. In this experiment, large-fruited tomato was grown at three fertilizer levels; 11.3 gN (LF), 16.2 gN (MF), 21.0 gN (HF) per plant to evaluate a suitable level of controlled-release fertilizer needed for the culture of 15 trusses between October and July. For HF, the experiment was terminated at the end of December due to severe wilting. There was no significant difference in marketable fruits weight between LF and MF, but the soluble sugar content was higher in MF. The stem diameter at the end of experiment was larger in MF. The amount of nutrient remaining in the substrate was lower for N, P 2 O 5 and K 2 O, but greater for CaO and MgO at each fertilizer level. Each nutrient concentration in the substrate solution was low after the middle of February for both LF and MF. Therefore, enrichment of nutrients in the substrate solution did not occur in either LF or MF. In conclusion, the amount of 16.2 gN per plant may have been sufficient for 15 trusses of tomatoes undergoing forcing culture.

Differential Nutrient Uptake and Its Transport in Tomato Plants on Different Fertilizer Regimens

“…In the CRF treatment, all the inorganic minerals were maintained near the threshold uptake level (i.e., minimum level required for a normal uptake) reported by Hosoi and Hosono (2005). These trends are in agreement with our previous results (Kinoshita et al, 2010a(Kinoshita et al, , 2010b. On the other hand, mineral concentrations in the CRF-treated xylem exudates after the harvesting of fruits from the first truss were much higher than the mineral concentrations in the substrate solution, similar to those observed for the LF treatment until the period of stem topping, as mentioned previously.…”

“…Plants were supplied with CRF or LF. The nutrient composition of CRF was determined from our previous results (Kinoshita et al, 2010a(Kinoshita et al, , 2010b, and nutrient release from CRF was simulated using nutrient release simulation software (Sehi-meijin Version 2.0; JA Zen-noh, Tokyo, Japan). The nutrient components of CRF are shown in Table 1.…”

“…Furthermore, mineral concentrations in the substrate solutions were extremely low after the first half of the experiment with CRF application (Kinoshita et al, 2010a(Kinoshita et al, , 2010b. Imano et al (2011) have also reported that the electrical conductivity (EC) of the substrate solution is very low after the first half of the growth period with CRF application.…”

“…Compared with LF, CRF is economical, because it does not require equipment for adjustment of nutrient concentration and fertilizer delivery. In our previous study, we established that for harvesting 15 trusses, the optimal nitrogen supply is 16.2 g per plant (Kinoshita et al, 2010a(Kinoshita et al, , 2010b if the timing of nutrient release from the CRF was optimized and that nutrient utilization efficiency was higher with CRF than with LF (Kinoshita et al, 2010b).…”

Decision Support System and Fuzzy Logic Controller for Capillary Irrigation System

“…Similar researches on capillary irrigation showing enhanced water efficiency has also been reported (Masuda, 2008;Kinoshita et al, 2010;Ferrarezi and Testezlaf, 2016;Kamal et al, 2019). However, it has been observed that the upward movement of water via capillary action irreversibly accumulates salts in the soil media, and the salinity of water in the soil is not negligible unless water leaching occurs, hence proper monitoring and control of water supply to the capillary interface is achieved (Fujimaki et al, 2018).…”