Application of gibberellin treatments in young and mature avocado trees to improve growth and yield under heat stress conditions
Research team: Dr. Vered Irihimovitch (PI) and Dr.Tarin Paz-Kagan (Co-PI)
MSc: Mr. Tal Shahar
Fertilizer N inputs in mature citrus orchards typically range between 150 and 350 kg ha-1 yr-1. Leaching losses of N can be high (50–150 kg ha-1 yr-1), especially when the application of N fertilizer and water is not done by micro-irrigation systems (i.e. drip and micro-sprinklers) close to plant roots, and when the application does not follow crop demand. These N losses contribute to pollution of groundwater and surface water bodies and there is, therefore, a great need to reduce these losses. Even under best management practices (BMPs), the N use efficiency (NUE) in citrus orchards remains fairly low (40 – 60 %). Therefore the aims of the study are: (1) Identify the spatial and temporal variability in N status across the orchard in a landscape scale, for developing SSM, by using tree-based N management to minimize N leakiness. (2) Correlating between the temporal (monthly) leaf N status, the ”Standard” leaf N status (i.e. October-November samples), and the fruit yield per tree. (3) Toping fertigation with a tree-based application of controlled release N fertilizer to account for tree N status and needs. (4) Correlate spatial and temporal variation pattern in N status to N leaching and N use efficiency using remote sensing applications
