YIELD LOSSES, YIELD EFFICIENCY AND PROFITABILITY OF APPLE ORCHARDS WITH DIFFERENT TECHNOLOGY LEVELS IN CHIHUAHUA, MÉXICO

Abstract

During the 2001-2002 apple [Malus sylvestris (L.) Mill. var domestica (Borkh) Mansf.] growing seasons, yield and fruit drop kinetics due to pest injury, poor pollination and fruit natural drop were monitored in 13 apple orchards with three levels of technology: low, medium and high. Data were analyzed by the mean test comparison, exponential curve, regression and partial budget analysis to estimate each production system profit. Results indicated that dropped fruits caused by machinery labor practices (weed management and sprays) was the main yield loss (11.3 %), losses caused by moldy core disease (Alternaria spp) reached 9.2 % and by colding moth (Cydia pomonella) injury 5.8 %. Total yield losses were 21.8 %. High technology orchards showed highest yield efficiency (number of fruits by invested peso); however, these orchards had also the biggest losses. There was a great variability in yields between years in medium and low technology level orchards.