New Zealand mistletoes have equal or lower capacities for electron transport than their hosts

Abstract

previous work on the New Zealand mistletoes Ileostylus micranthus and Tupeia antarctica indicates that these mistletoes have lower maximum electron transport rates (ETR_max) than their hosts. We extend this research by testing Seven of the eight extant endemic New Zealand mistletoes using chlorophyll fluorescence measurements. In addition, we examined whether loranthaceous (Alepis flavida_&Ileostylus micranthus, peraxilla Colensoi p. tetra‐petala Tupeia antarctica) and viscaceous mistletoes (Korthalsella Iindsayi, K. salicornioides) differed in their capacities for electron transport. Electron transport rates were significantly related to photosyn‐thetically active Photon flux densities (PPFD). Overall, mistletoes had significantly lower (110 ± 18 mol m^‐ s^‐1) ETR_max than their hosts (219 ± 43 mol m^‐2 S^‐1) but Some specific host‐mistletoes Pairs showed no significant difference in ETR_max There was no clear distinction in ETR_max between mistletoe families. We conclude that New Zealand mistletoes generally have lower electron transport rates at the same PPFD and, usually, lower photosynthetic capacities than their hosts.

Keywords:

• Loranthaceae
• Viscaceae
• New Zealand
• mistletoe
• chlorophyll florescence
• electron transport rate
• photon flux density
• PAR
• CO₂ assimilation