Mendel, Z., & Liphschitz, N. 1988 Unseasonable latewood and incrusted pits are the cause of drying in Pinus halepensis and P. eldarica infested with Matsucoccus josephi.. Journal of Experimental Botany 39(204): 951-959.
Notes: Abstract: A study of the effects of Matsucoccus josephi on water transport in three Pinus species using a scanning electron microscope; transport of the fuchsin dye was arrested below the affected zone of heavily infested shoots, but reached the shoot apex through sparsely infested segments or via segments heavily infested with the first larval stage; description of damage; it is suggested that blocking of water ascent in P. halepensis and P. eldarica starts when female second-instar larvae complete their development and only when population density is relatively high; therefore, it is considered that the accelerated drying of the growth of these two species is directly related to the narrowing of the pit apertures, which resembled those of latewood pits although produced early in the season; the structural modification of the xylem caused by this scale may be related to imbalance in plant growth hormones which are either transmitted with the insect saliva or formed in the plant by salivary enzymes.