This paper describes an approach to estimate the photosynthetic capacity and derive the optimum fruit number for each individual tree, in order to achieve a defined fruit size, which is named as the fruit bearing capacity of the tree. The estimation of fruit bearing capacity was carried out considering the total leaf area per tree as measured with a 2-D LiDAR laser scanner, LA LiDAR , and key carbon-related variables of the trees including leaf gas exchange, fruit growth and respiration, in two commercial apple orchards. The range between min LA LiDAR and max LA LiDAR was found to be 2.4 m² on Pinova and 4.3 m² on RoHo 3615 at fully developed canopy. The daily C requirement of the growing fruit and the associated leaf area demand, necessary to meet the average daily fruit C requirements showed seasonal variation, with maximum values in the middle of the growing period. The estimated fruit bearing capacity ranged from 33-95 fruit tree -1 and 45-121 fruit tree -1 on the trees of Pinova and RoHo 3615, respectively. This finding demonstrates sub-optimal crop load at harvest time in both orchards, above or below the fruit bearing capacity for individual trees. In conclusion, the LiDAR measurements of the leaf area combined with a carbon balance model allows for the estimation of fruit bearing capacity for individual trees for precise crop load management. K e y w o r d s: fruit growth rate, fruit respiration, leaf area, LiDAR, precision horticulture

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yield and fruit quality in the production of apple fruit. thinning. In the years 2011, 2014-2016, commercial orchards of 'Elstar'/M26 and 'Gala'/M9 trained as set were mechanically thinned at balloon stage (BBCH 59) with the Darwin 250 device at constant vehicle speed of 8 km h -1 with varying rotational frequency ranging from 200 revolutions per minute (rpm) to 380 rpm. Rotational frequency of the thinning device was translated to average kinetic energy (E kin [J]) production target of 119 fruit and, therefore, no yield loss by over-thinning without any positive effect of 0.23 J and 0.33 J were adequate settings to reduce crop load in 'Elstar' and 0.33 J in 'Gala' without yield the avoidance of yield loss by over-thinning of trees -1 in 'Elstar' and 2.6-7.6 t ha -1 in 'Gala'. Results indicate the to the tree's yield capacity.

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