Abstract Detail

Ecological Section

Araujo, Nayara [1], Santos, Jean Carlos [1], Silva, Henrique Venancio [1], Andrade, Janete [1], Silva, Estevão [1], Ameida, Wanessa Rejane [1], Carmo-Oliveira, Renata [2].

How detrimental are seed-galls to their hosts? tolerance to herbivory in a polyembryonic legume tree.

Galls are an atypical growth and differentiation form of plant tissue. Gall-inducers use these structures as shelters and source of nutrition, consequently, they cause multiple physiological changes in host plants, altering host traits, growth and survival. We studied the impact caused by a sarcotesta-gall Allorhogas sp. (Hymenoptera: Braconidae) on fruits, seeds, and seedlings performance of its host plant Inga laurina (Sw.) Willd. (Fabaceae). We tested whether sarcotesta-galls are ‘nutrient sinks’ in the fruit/seed of host plant, consequently restraining reproductive ability and reducing longevity of seedlings. We measured the gall influence on the secondary compounds in tissues, fruit and seeds parameters, seed germination and viability, and seedlings performance. Galled tissues produced a sarcotesta with higher phenols concentrations, around 7 times more that ungalled tissues. This result suggests the action of these substances in chemical defences of gall against herbivory or their natural enemies. Galling caused a significant reduction in fruit and seed parameters, such as fruit and seed sizes, seed weight, and number of embryos. However, these negative effects were not sufficient to reduce the seed germination (except synchronization index) and seedling performance (except foliar area and chlorophyll contents), though they induced 30% more asymmetry on leaves of plants germinated from galled-seeds than from non-galled-seed plants. Plants are able to tolerate herbivore damage to different degrees along their development. We attributed these results to the ability of I. laurina to tolerate attack of Allorhogas sp. on seeds without great influence on seedling performance. Moreover, due the intensity of seed galling on host plant, we suggest that polyembryony may play a role in I. laurina reproduction by compensating for losses due to seed predation. Although our results showed that the presence of galls could reduce the number of embryos in the seeds, the extranumerary embryos in galled seeds can remain active and develop into seedlings. These trade-offs between galling/herbivory, polyembryony and host reproduction should be further investigated. (CAPES, FAPEMIG, CNPq)

1 - Universidade Federal de Uberlandia, Instituto de Biologia, Bloco 2D. Campus Umuarama, Uberlandia, MG, 38405-320, Brazil
2 - Universidade Federal de Uberlandia, Instituto de Biologia, Uberlandia, MG, 38405-320, Brazil

Keywords:
inga
Fabaceae
Brazil
Cerrado
phenols
polyembryony
Braconidae.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PEC019
Abstract ID:1040
Candidate for Awards:None