Impact of Leptoglossus occidentalis on commercial pine nut kernel per cone output
The aim of this work was to quantify the extent of the recent decline observed in pine nut and kernel production. For this purpose, we analysed data from the INIA long-term sample plot network for cone and pine nut production in the four main Spanish stone pine regions. Data series for more than a hundred plots since the last century, previous to the arrival of the bug, were compared with the same series after its arrival. Hence, the collapse in kernel per cone yield since can be quantified, the implied main factors identified, and the evidence of L. occidentalis causality...