TY  - JOUR
A1  - Schleuning, Matthias
A1  - Templin, Mathias
A1  - Huaman, Vicky
A1  - Vadillo, Giovana P.
A1  - Becker, Thomas
A1  - Durka, Walter
A1  - Fischer, Markus
A1  - Matthies, Diethart
T1  - Effects of inbreeding, outbreeding, and supplemental pollen on the reproduction of a hummingbird-pollinated clonal amazonian herb
JF  - Biotropica : a publication of the Association for Tropical Biology
N2  - Understory herbs are an essential part of tropical rain forests, but little is known about factors limiting their reproduction. Many of these herbs are clonal, patchily distributed, and produce large floral displays of nectar-rich 1-d flowers to attract hummingbird pollinators that may transport pollen over long distances. The aim of this study was to investigate the effects of clonality, cross-proximity, and patchy distribution on the reproduction of the hummingbird-pollinated Amazonian herb Heliconia metallica. We experimentally pollinated flowers within populations with self-pollen and with pollen of different diversity, crossed flowers between populations, and added supplemental pollen to ramets growing solitarily or in conspecific patches. Only flowers pollinated early in the morning produced seeds. Selfed flowers produced seeds, but seed number and mass were strongly reduced, suggesting partial sterility and inbreeding depression after selfing. Because of pollen competition, flowers produced more seeds after crosses with several than with single donor plants. Crosses between populations mostly resulted in lower seed production than those within populations, suggesting outbreeding depression. Ramets in patches produced fewer seeds than solitary ramets and were more pollen-limited, possibly due to geitonogamy and biparental inbreeding in patches. We conclude that high rates of geitonogamy due to clonality and pollen limitation due to the short receptivity of flowers and patchy distribution constrain the reproduction of this clonal herb. Even in unfragmented rain forests with highly mobile pollinators, outbreeding depression may be a widespread phenomenon in plant reproduction.
KW  - clonality
KW  - geitonogamy
KW  - Heliconiaceae
KW  - hummingbird pollination
KW  - Peru
KW  - pollen limitation
KW  - pollination experiment
KW  - rain forest understory
Y1  - 2011
U6  - https://doi.org/10.1111/j.1744-7429.2010.00663.x
SN  - 0006-3606
VL  - 43
IS  - 2
SP  - 183
EP  - 191
PB  - Wiley-Blackwell
CY  - Malden
ER  - 
TY  - JOUR
A1  - Hempel, Hannes
A1  - Savenjie, Tom J.
A1  - Stolterfoht, Martin
A1  - Neu, Jens
A1  - Failla, Michele
A1  - Paingad, Vaisakh C.
A1  - Kužel, Petr
A1  - Heilweil, Edwin J.
A1  - Spies, Jacob A.
A1  - Schleuning, Markus
A1  - Zhao, Jiashang
A1  - Friedrich, Dennis
A1  - Schwarzburg, Klaus
A1  - Siebbeles, Laurens D. A.
A1  - Dörflinger, Patrick
A1  - Dyakonov, Vladimir
A1  - Katoh, Ryuzi
A1  - Hong, Min Ji
A1  - Labram, John G.
A1  - Monti, Maurizio
A1  - Butler-Caddle, Edward
A1  - Lloyd-Hughes, James
A1  - Taheri, Mohammad M.
A1  - Baxter, Jason B.
A1  - Magnanelli, Timothy J.
A1  - Luo, Simon
A1  - Cardon, Joseph M.
A1  - Ardo, Shane
A1  - Unold, Thomas
T1  - Predicting solar cell performance from terahertz and microwave spectroscopy
JF  - Advanced energy materials
N2  - Mobilities and lifetimes of photogenerated charge carriers are core properties of photovoltaic materials and can both be characterized by contactless terahertz or microwave measurements. Here, the expertise from fifteen laboratories is combined to quantitatively model the current-voltage characteristics of a solar cell from such measurements. To this end, the impact of measurement conditions, alternate interpretations, and experimental inter-laboratory variations are discussed using a (Cs,FA,MA)Pb(I,Br)(3) halide perovskite thin-film as a case study. At 1 sun equivalent excitation, neither transport nor recombination is significantly affected by exciton formation or trapping. Terahertz, microwave, and photoluminescence transients for the neat material yield consistent effective lifetimes implying a resistance-free JV-curve with a potential power conversion efficiency of 24.6 %. For grainsizes above approximate to 20 nm, intra-grain charge transport is characterized by terahertz sum mobilities of approximate to 32 cm(2) V-1 s(-1). Drift-diffusion simulations indicate that these intra-grain mobilities can slightly reduce the fill factor of perovskite solar cells to 0.82, in accordance with the best-realized devices in the literature. Beyond perovskites, this work can guide a highly predictive characterization of any emerging semiconductor for photovoltaic or photoelectrochemical energy conversion. A best practice for the interpretation of terahertz and microwave measurements on photovoltaic materials is presented.
KW  - lifetime
KW  - microwaves
KW  - mobility
KW  - solar cells
KW  - terahertz
Y1  - 2022
U6  - https://doi.org/10.1002/aenm.202102776
SN  - 1614-6832
SN  - 1614-6840
VL  - 12
IS  - 13
PB  - Wiley
CY  - Weinheim
ER  -