Conference Paper

Orange yield and plant gap mapping caused by disease

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Abstract

Precision agriculture techniques have been applied to citrus production such as yield mapping and management systems that recognize field spatial variability. The objective of the present study was to characterize yield spatial variability and mapping density of plant gaps caused by citrus blight and huanglongbing (HLB) in a commercial orange orchard in São Paulo State, Brazil. Volume, co-ordinates and representative areas of the bags used for harvesting a 12-year-old Valencia orange orchard were recorded to produce the yield map. This data was used to generate yield points that were then interpolated to produce the map. A gap density map was made by geo-referencing gaps and later counting the number of gaps within cells with known area. Data were submitted to statistical and geostatistical analyses. Great variation in yield and gap density was observed from the maps. They presented overlapping spots of high density of plant absence and low fruit yield.

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