Water: the key factor limiting yields of Australian drip irrigated processing tomatoes

In Australia, processing tomatoes are grown in the irrigation districts of the central Murray valley using sub-surface drip irrigation.
The industry wishes to lift yields but believes low soil pH and poor soil structure are major impediments to achieving their 200 t ha^‑1 target.
However, past efforts to ameliorate soils have not led to improvements in yield.
This study monitored nine commercial tomato crops during the 2019-2020 season to assess yield limiting factors, with the hypothesis that water stress is the major constraint.
A highly significant correlation (R²=78%) was found between red fruit yield and the number of days the soil was either waterlogged or too dry during January and February, supporting the hypothesis.
This was mainly an issue in the chromosol soils and efforts should be directed to addressing problems in this soil type.
Deep drainage losses under current irrigation regimes were high (leaching fractions of 34-52% and 11-38% for the chromosols and vertosols respectively) and the adoption of sensor-based irrigation scheduling is recommended for all soil types.

XVI International Symposium on Processing Tomato

S.H. North

NDVI, canopy temperature, matric potential

https://doi.org/10.17660/ActaHortic.2022.1351.10