Fruit abortion in Yucca elata and its implications for the mutualistic association with yucca moths [Tegeticula yuccasella]

The yucca moth Tegeticula yuccasella is the sole pollinator of Yucca elata, and relies on yucca fruits to complete its life cycle. A high percentage of pollinated flowers aborts, killing the T. yuccasella eggs and larvae in them. We examined patterns of fruit production and abortion in Y. elata, and...

Full description

Saved in:
Bibliographic Details
Published in:Oikos 1994-03, Vol.69 (2), p.207-216
Main Authors: James, C.D, Hoffman, M.T, Lightfoot, D.C, Forbes, G.S, Whitford, W.G
Format: Article
Language:English
Subjects:
ABSCISION
ABSCISSION
Animal and plant ecology
Animal, plant and microbial ecology
Animals
Autoecology
Biological and medical sciences
CAIDA PREMATURA DE FRUTOS
CHUTE DE FRUITS
CICLO VITAL
CLIMATIC FACTORS
CYCLE DE DEVELOPPEMENT
DATOS DE PRODUCCION
DONNEE DE PRODUCTION
ETAPAS DE DESARROLLO DE LA PLANTA
FACTEUR CLIMATIQUE
FACTORES CLIMATICOS
FLEUR
FLORES
FLOWERS
Fruit abortion
FRUIT DROP
Fruit production
FRUITS
FRUTAS
Fundamental and applied biological sciences. Psychology
HOST PARASITE RELATIONS
Inflorescences
INSECTA
Invertebrates
Larvae
LIFE CYCLE
Moths
OVA
Oviposition
OVULE
OVULO
PLANT DEVELOPMENTAL STAGES
Plants
POLINIZADORES
Pollination
POLLINATORS
POLLINISATEUR
PRODUCTION DATA
Protozoa. Invertebrata
RELACIONES HUESPED PARASITO
RELATION HOTE PARASITE
STADE DE DEVELOPPEMENT VEGETAL
SUPERVIVENCIA
SURVIE
SURVIVAL
YUCCA
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The yucca moth Tegeticula yuccasella is the sole pollinator of Yucca elata, and relies on yucca fruits to complete its life cycle. A high percentage of pollinated flowers aborts, killing the T. yuccasella eggs and larvae in them. We examined patterns of fruit production and abortion in Y. elata, and related these patterns to vegetative characteristics, moth abundance, and environmental conditions. We studied 38 inflorescences throughout their flowering period, during one season in southern New Mexico, USA. Each night we recorded the number of flowers opening, the number of fruit formed, the relative abundance of yucca moths, and climatic conditions. We monitored 11786 flowers, resulting in 699 mature fruit. Large inflorescences produced more, but proportionately fewer fruit than small inflorescences. Inflorescences flowering late in the season produced proportionately more fruit than inflorescences flowering early. Only 6.6% (extremes 1.4-15.1%) of flowers produced mature fruits. Hand-pollination of all flowers on inflorescences did not significantly increase the proportion of flowers that developed into mature fruit. Fruit production appeared to be resource-, not pollinator-limited. Ninety per cent of observed moth-pollinated flowers aborted (N = 31), resulting in the death of moth eggs and larvae laid in the flowers. Neither yucca moth abundance or climatic conditions correlated with fruit production. Inflorescences usually developed mature fruit from flowers opening during a 'window' of consecutive nights, lasting for five nights on average (36% of the flowering period of an inflorescence). The timing of the window of fruit production was highly variable and unpredictable: mature fruits were produced from flowers opening at the beginning, in the middle, or at the end of the flowering period of an inflorescence. The results for Y. elata do not support existing hypotheses that attempt to explain patterns of selective fruit production. High rates of abortion of initiated fruit, and the apparently unpredictable pattern of fruit production by individual inflorescences, may stabilize the mutualistic interaction by preventing yucca moths from hyper-ovipositing flowers that have a high probability of developing into mature fruits. A risk-spreading strategy of oviposition is likely to be more successful for the moth than multiple ovipositions per flower.
ISSN:0030-1299
1600-0706
DOI:10.2307/3546140