DEVELOPMENT OF A SIMPLIFIED AND HIGHLY NUTRIENT-EFFICIENT FERTILIZATION METHOD BY USING CONTROLLED-RELEASE FERTILIZER IN TOMATO CULTIVATION
We developed a simplified and highly nutrient-efficient soilless culture system for tomato cultivation using a fertigation system with controlled-release fertilizer (CRF). Plants in a greenhouse were supplied with CRF at 3 nutrient levels (Low, Middle and High) in a closed system or with liquid fertilizer (LF) at a constant electrical conductivity (EC) in a habitual open system from August to December 2011. The plants were pinched, leaving 2 leaves above the fourth trusses. Total N input and apparent N uptake by the plants in the LF treatment were similar to those in the High treatment and higher than were those in the Low and Middle treatments. Total and marketable fruit yields were similar among the LF, Middle, and High treatments, but lower in the Low treatments. The leaf area index (LAI) was significantly higher in the High than in the LF treatment, and there were no significant differences between the Middle treatment and the High or LF treatments. In the low treatments, LAI was considerably lower than that in the other treatments. The Middle treatment resulted in a similar LAI and fruit yield with high N-use efficiency compared to the LF treatment. In conclusion, compared to an EC-based LF application, application of an appropriate amount of CRF resulted in the same level of fruit yield despite lower nutrient use.
Kinoshita, T., Sugiura, M. and Nagasaki, Y. (2014). DEVELOPMENT OF A SIMPLIFIED AND HIGHLY NUTRIENT-EFFICIENT FERTILIZATION METHOD BY USING CONTROLLED-RELEASE FERTILIZER IN TOMATO CULTIVATION. Acta Hortic. 1034, 517-524
fruit yield, leaf area index, nitrogen, nutrient use efficiency, soilless culture, Solanum lycopersicum