COFFEE SHADE WITH MIMOSA-SCABRELLA BENTH FOR FROST PROTECTION IN SOUTHERN BRAZIL

Damage by radiative frosts is a major limiting factor for coffee culti vation in southern Brazil (south of 20 degrees S latitude). The use of Mimosa scabrella (bracatinga) as a shade tree, to modify the local en ergy balance and thus prevent damage to the coffee plants, has been ev aluated from 1986 to 1994. The study was carried out near Londrina, Pa rana State (23 degrees 23' S, 51 degrees 11' W). During the experiment al period, several radiative frosts with intensity ranging from modera te to very severe occurred at the site. Minimum coffee leaf temperatur es during these events were 2 to 4 degrees C higher in the shaded plot s. Due to frost protection, coffee bean yields on the average of 7 har vests were higher on the shaded plots. The potential of this system fo r frost protection in southern Brazil is discussed.