TY - JOUR TI - RESPIRATORY OXYGEN RESPONSE AND RESPIRATORY QUOTIENT OF APPLE STEM SECTIONS DURING CHILLING AU - YOUNG, E T2 - JOURNAL OF THE AMERICAN SOCIETY FOR HORTICULTURAL SCIENCE AB - During natural leaf abscission, 2-year-old potted apple trees (Malus domestica Borkh. cv. MM.111 EMLA) were placed in a room at 6C for chilling [0,600, 900, or 1400 chilling units (CU)]. After each chilling treatment, respiration of shoot segments was measured as CO 2 evolved and O 2 consumed at 22C in several O 2 concentrations. Respiration increased with oxygen concentration after all CU treatments. Carbon dioxide evolved at the several O 2 levels did not show a pattern related to CU, but O 2 consumed decreased at a decreasing rate with additional CU. Respiratory quotient was <1 at 0 and 600 CU and equal to 1 at 900 and 1400 CU, indicating a possible shift in respiratory substrate with chilling. DA - 1993/7// PY - 1993/7// DO - 10.21273/jashs.118.4.509 VL - 118 IS - 4 SP - 509-512 SN - 0003-1062 KW - BUDBREAK KW - BUD DORMANCY KW - MALUS-DOMESTICA ER -