Particle film application influences apple leaf physiology, fruit yield, and fruit quality

Particle film technology is a developing pest control system for tree fruit production systems. Trials were performed in Santiago, Chile, and York Spr ings, Pa., Wenatchee and Yakima, Wash., and Kearneysville, W. Va., to evalu ate the effect of particle treatments on apple [Malus sylvestris (L,) Mill. var, domestica CBorkh) Manst.] leaf physiology, fruit yield, and fruit qua lity. Leaf carbon assimilation was increased and canopy temperatures were r educed by particle treatments in seven of the eight trials. Yield and/or fr uit weight was increased by the particle treatments in seven of the eight t rials. In Santiago and Kearneysville, a* values of the fruit surface were m ore positive in all trials although a* values were not increased in Wenatch ee and Yakima, Results indicate that particle film technology is an effecti ve tool in reducing heat stress in apple trees that may result in increased yield potential and quality.