scholarly journals Which Seed Properties Determine the Preferences of Carabid Beetle Seed Predators?

Insects ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 757
Author(s):  
Foffová Hana ◽  
Ćavar Zeljković Sanja ◽  
Honěk Alois ◽  
Martinková Zdenka ◽  
Tarkowski Petr ◽  
...  
Keyword(s):  
Seed Coat ◽  
Explanatory Power ◽  
Seed Mass ◽  
Carabid Beetles ◽  
Plant Strategy ◽  
Seed Predators ◽  
Lack Of Information ◽  
Complete Set ◽  
Morphological Defence ◽  
Explained Variance

Ground beetles are important invertebrate seed predators in temperate agro-ecosystems. However, there is a lack of information regarding which seed properties are important to carabids when they select seeds for consumption. Therefore, seed properties, such as size, shape, morphological defence, and chemical composition, were measured, and in addition to seed taxonomy and ecology, these data were used to explain carabid preferences. Carabid preferences were assessed using a multi-choice experiment with 28 species of weed seeds presented to 37 species of Carabidae. Multiple regression on distance matrices (MRM) was used to determine the importance of particular sets of seed properties for carabids. The analysis was conducted for the full set of carabids (37 species) as well as for subsets of species belonging to the tribes of Harpalini or Zabrini. For the complete set of species, seed dimensions, seed mass, taxonomy, plant strategy, and seed coat properties significantly explained carabid preferences (proportion of explained variance, R2 = 0.465). The model for Harpalini fit the data comparably well (R2 = 0.477), and seed dimensions, seed mass and seed coat properties were significant. In comparison to that for Harpalini, the model for Zabrini had much lower explanatory power (R2 = 0.248), and the properties that significantly affected the preferences were seed dimensions, seed mass, taxonomy, plant strategy, and seed coat properties. This result suggests that the seed traits that carabids respond to may be specific to taxonomic and likely relate to the degree of specialisation for seeds. This study contributes to understanding the mechanisms that determine the preferences of carabid beetles for seeds.

scholarly journals Do properties and species of weed seeds affect their consumption by carabid beetles?

2020 ◽  
Vol 66 (Suppl.) ◽  
pp. 37-48
Author(s):  
Hana Foffová ◽  
David A. Bohan ◽  
Pavel Saska
Keyword(s):  
Seed Coat ◽  
Selection Process ◽  
Ground Beetle ◽  
Taraxacum Officinale ◽  
Carabid Beetles ◽  
Seed Selection ◽  
Seed Predators ◽  
Significant Difference ◽  
Anchomenus Dorsalis ◽  
Pterostichus Melanarius

Seed predators are an integral part of agroecosystems, where they can reduce the populations of weeds. The preference of predators for seeds and the observed predation rate may be affected by the properties of seeds (e.g. taxonomy, chemical composition, physical defence). In this work, we focused on seed consumption of Taraxacum officinale Web. and Stellaria media (L.) Vill., from France and the Czech Republic, by three species of ground beetle that are seed predators (Coleoptera: Carabidae): Poecilus cupreus (Linnaeus), Pterostichus melanarius (Illiger) and Anchomenus dorsalis (Pontoppidan). The seed species were offered in arenas, simultaneously, under three different experimental manipulations of moisture and seed coat conditions: dry and intact, water-imbibed and intact, and water-imbibed with a damaged seed coat. Seed consumption was checked after 0.5, 1, 2, 24, and 48 hours of exposure. Anchomenus dorsalis largely refused to feed on seeds. Taraxacum officinale seeds with damaged coats were most preferred by the remaining two species of carabids. The consumption by P. cupreus of T. officinale seeds with damaged coats increased from 0.18 % after 0.5 hours to 83.83 % after 48 hours, and by P. melanarius from 13.76 % after 0.5 hours to 76.77 % after 48 hours. Seeds of S. media were consumed less. There was a significant difference in consumption rates due to the country of origin of the seeds, but there were no differences between the carabid sexes. That carabids preferred water-imbibed and damaged seeds may suggest an involvement of olfactory clues in the seed selection process, and/or shorter seed-handling times.

Seed-coat thickness data clarify seed size–seed-bank persistence trade-offs inAbutilon theophrasti(Malvaceae)

2014 ◽  
Vol 24 (2) ◽  
pp. 119-131 ◽  
Author(s):  
Brian J. Schutte ◽  
Adam S. Davis ◽  
Stephen A. Peinado ◽  
Jamshid Ashigh
Keyword(s):  
Seed Size ◽  
Seed Coat ◽  
Seed Bank ◽  
Explanatory Power ◽  
Seed Mass ◽  
Trade Offs ◽  
Selection For ◽  
Viable Seeds ◽  
Seed Coats ◽  
Size Data

AbstractTheoretical models predict that seed size and seed-bank persistence evolve interdependently, such that strong selection for one trait corresponds with weak selection for the other. This framework has been supported and rejected by empirical data, and thus, conclusive evidence is lacking. We expanded the seed size–persistence framework to include seed-coat thickness, a defence trait previously correlated with seed survival in soil. To do this, we usedAbutilon theophrastiaccessions with varied evolutionary histories and we quantified associations among seed traits including morphology, size, coat thickness, dormancy (percentage of viable seeds that fail to germinate under optimum conditions) and seed-bank persistence (percentage of viable seeds remaining after 1 year of burial). Statistical models were developed to test the hypothesis that combined measurements of seed-coat thickness and seed size better explain variability in seed-bank persistence than seed-size data alone. Results indicated that measurements of seed size (length, width, mass) were negatively correlated with coat:width ratio (coat thickness relative to seed width) and coat:mass ratio (coat thickness relative to seed mass). Accessions characterized by smaller seeds with proportionally thicker seed coats were more dormant and more persistent in soil than accessions characterized by larger seeds with proportionally thinner seed coats. Seed-coat thickness data improved the explanatory power of logistic regression models for seed-size effects on both seed-bank persistence and dormancy. These results indicate that supplementing seed-size data with seed-defence data may clarify previously reported contradictory results regarding trade-offs between seed size and seed-bank persistence.

scholarly journals Using trait data improves correlation between environment and community data only if abundances are considered

2021 ◽  
Author(s):  
Attila Lengyel ◽  
Sándor Barabás ◽  
Boglárka Berki ◽  
Anikó Csecserits ◽  
Adrienn Gyalus ◽  
...  
Keyword(s):  
Explanatory Power ◽  
Seed Mass ◽  
Analysis Data ◽  
Variance Partitioning ◽  
Procrustes Analysis ◽  
Geographical Distance ◽  
Spatial Variables ◽  
Environmental Matching ◽  
Variation Explained ◽  
Analysis Models

AbstractA straightforward way to explore variation between communities is to calculate dissimilarity indices and relate them with environmental and spatial variables. Communities are most often represented by the (relative) abundances of taxa they comprise; however, more recently, the distribution of traits of organisms included in the communities has been shown more strongly related to ecosystem properties. In this study, we test whether taxon- or trait-based dissimilarity is correlated more tightly with environmental difference and geographical distance and how the abundance scale influences this correlation. Our study system is grassland vegetation in Hungary, where we sampled vegetation plots spanning a long productivity gradient from open dry grasslands to marshes in three sites. We considered three traits for vascular plants: canopy height, specific leaf area and seed mass. We obtained field estimates of normalized vegetation difference index (NDVI) as proxy of productivity (water availability) for each plot. We calculated between-community dissimilarities using a taxon-based and a trait-based index, using raw and square-root transformed abundances and presence/absence data. We fitted distance-based redundancy analysis models with NDVI difference and geographical distance on the dissimilarity matrices and evaluated them using variance partitioning. Then, using the pooled data, we calculated non-metric multidimensional scaling ordinations (NMDS) from all types of dissimilarity matrices and made pairwise comparisons using Procrustes analysis. Data analysis was done separately for the three sites.We found that taxonomical dissimilarity matches environmental and spatial variables better when presence/absence data is used instead of abundance. This pattern was mainly determined by the increasing variation explained by space at the presence/absence scale. In contrast to this trend, with trait-based dissimilarity, accounting for abundance increased explained variation significantly due to the higher explanatory power of NDVI. With abundance data, considering traits improved environmental matching to a great extent in comparison with taxonomical information. However, with presence/absence data, traits brought no advantage over taxon-based dissimilarity in any respect. Changing the abundance scale caused larger difference between ordinations in the case of trait-based dissimilarity than with taxonomical dissimilarity.We conclude that considering relevant traits improves environmental matching only if abundances are also accounted for.Supporting informationAdditional graphs supporting the results are presented as appendix.Open researchData used in this research are publicly available from Dryad ###link to be supplied upon acceptance###

Seed storage behaviour of 101 woody species from the tropical rainforest of southern China: a test of the seed-coat ratio–seed mass (SCR–SM) model for determination of desiccation sensitivity

2014 ◽  
Vol 62 (4) ◽  
pp. 305 ◽  
Author(s):  
Qin-ying Lan ◽  
Ke Xia ◽  
Xiao-feng Wang ◽  
Jun-wei Liu ◽  
Jin Zhao ◽  
...  
Keyword(s):  
Moisture Content ◽  
Seed Coat ◽  
Tropical Rainforest ◽  
Southern China ◽  
Seed Mass ◽  
Seed Storage ◽  
Woody Species ◽  
Seed Moisture Content ◽  
Seed Desiccation ◽  
Desiccation Sensitivity

The Xishuangbanna tropical rainforest in Yunnan Province is the greatest biodiversity hotspot in China. However, the biodiversity of this region is under threat, making seed conservation through seed and/or germplasm banking particularly urgent and crucial. Seed desiccation sensitivity limits the possibility of seed banking of 47% of tropical rainforest species. Thus, knowing if a species has desiccation-sensitive seeds is an important first step in seed banking; however, often resources are limited, making it difficult to determine storage behaviour for all the species in a region. Prediction of seed sensitivity using the SCR–SM model based on seed-coat ratio (SCR) and seed dry mass (SM) might be an alternative for determining desiccation sensitivity of seeds of each species. Here, seed-desiccation sensitivity of 101 woody species from the Xishuangbanna tropical forest were analysed using this model, and physiological determinations were made for a total of 25 species. Seed storage behaviour for 59 species was used for model validation, and storage behaviour of 88% of these species was successfully predicted. Seed storage behaviour of 83% of the 59 species was successfully predicted using the 1000-seed weigth–moisture content (TSW–MC) criteria, which include seeds with 1000-seed weight >500 g and seed moisture content at shedding of 30 –70%. The two predictive methods were subsequently used to predict seed desiccation sensitivity for another 42 species from Xishuangbanna whose storage behaviour was uncertain. Our results indicated that ~50% of the species in Xishuangbanna are likely to have desiccation-sensitive seeds.

scholarly journals Seed development in Paeonia ostii (Paeoniaceae), with particular reference to embryogeny

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Keliang Zhang ◽  
Weizhang Cao ◽  
Jerry M. Baskin ◽  
Carol C. Baskin ◽  
Jing Sun ◽  
...  
Keyword(s):  
Seed Development ◽  
Seed Coat ◽  
Soluble Sugars ◽  
Outer Integument ◽  
Dry Mass ◽  
Endosperm Development ◽  
Raw Material ◽  
Lack Of Information ◽  
Two Stages ◽  
Peripheral Cells

Abstract Background Seeds of Paeonia ostii have been proposed as a source of raw material for the production of edible oil; however, lack of information about the developmental biology of the seeds hampers our ability to use them. Our aim was to investigate development of the seed coat, endosperm and embryo of P. ostii in relation to timing of accumulation of nutrient reserves from pollination to seed maturity. Ovules and developing seeds of P. ostii were collected at various stages of development from zygote to maturity. Seed fresh mass, dry mass, germination, moisture, soluble sugars, starch, protein and oil content were determined. Ontogeny of seeds including embryo, endosperm and seed coat were analyzed histologically. Results The ovule of P. ostii is anatropous, crassinucellate and bitegmic. The zygote begins to divide at about 5 days after pollination (DAP), and the division is not accompanied by cell wall formation. By 25 DAP, the proembryo begins to cellularize. Thereafter, several embryo primordia appear at the surface of the cellularized proembryo, but only one matures. Endosperm development follows the typical nuclear type. The seed coat is derived from the outer integument. During seed development, soluble sugars, starch and crude fat content increased and then decreased, with maximum contents at 60, 80 and 100 DAP, respectively. Protein content was relatively low compared with soluble sugars and crude fat, but it increased throughout seed development. Conclusions During seed development in P. ostii, the seed coat acts as a temporary storage tissue. Embryo development of P. ostii can be divided into two stages: a coenocytic proembryo from zygote (n + n) that degenerates and a somatic embryo from peripheral cells of the proembryo (2n → 2n). This pattern of embryogeny differs from that of all other angiosperms, but it is similar to that of gymnosperms.

scholarly journals Using endocarp-remains of seeds of wild apricot Prunus armeniaca to identify rodent seed predators

2009 ◽  
Vol 55 (6) ◽  
pp. 396-400
Author(s):  
Hongmao Zhang ◽  
Wei Wang
Keyword(s):  
Seed Coat ◽  
Prunus Armeniaca ◽  
Linear Discriminant ◽  
Hard Seed ◽  
Seed Predators ◽  
Quantitative Studies ◽  
Chinese White ◽  
Wild Apricot ◽  
Field Mice ◽  
Hard Seed Coat

Abstract Some rodent-dispersed seeds have a hard seed-coat (e.g.woody endocarp). Specific scrapes or dental marks on the hard seed-coat left by rodents when they eat these seeds can be used to identify seed predators. In this study we measured the morphological traits of endocarp-remains of seeds of wild apricot Prunus armeniaca used by Chinese white-bellied rats Niviventor confucianus and Korean field mice Apodemus peninsulae. We established their Fisher’s linear discriminant functions to separate endocarp-remains between the two predators. A total of 90.0% of the endocarp-remains left by Korean field mice and 88.0% of those left by Chinese white-bellied rats were correctly classified. The overall percentage of correct classification was 89.0%. One hundred and sixty endocarp-remains of unknown what species predated them were classified using the functions. The method may allow more reliable quantitative studies of the effects of Chinese white-bellied rats and Korean field mice on seed consumption and dispersal of wild apricot and this study might be used for reference in other studies of seed predators identification on hard seeds.

How Well Do Bibliometric Indicators Correlate With Scientific Eminence? A Comment on Simonton (2016)

2019 ◽  
Vol 15 (1) ◽  
pp. 202-203
Author(s):  
Marco Del Giudice
Keyword(s):  
Recent Literature ◽  
Explanatory Power ◽  
Scientific Productivity ◽  
Original Data ◽  
Regression Coefficients ◽  
H Index ◽  
Psychological Science ◽  
Original Analysis ◽  
Explained Variance ◽  
Bibliometric Index

Citing an earlier study on eminence in psychology, Simonton (2016) argued that associations between measures of scholars’ reputation, scientific productivity, and citation counts are only small to moderate [Simonton, D. K. (2016). Giving credit where credit’s due: Why it’s so hard to do in psychological science. Perspectives on Psychological Science, 11, 888–892]. However, this reading is based on partial regression coefficients, which underestimate the joint explanatory power of correlated variables. A reanalysis of the original data showed that a composite bibliometric index was substantially associated with reputation (β = 0.70; 46% explained variance). Very similar results were obtained with a newly calculated h index (β = 0.67; 42% explained variance). Although both Simonton’s original analysis and the current reanalysis are inherently limited, the data suggest that the reputation of psychologists tracks their scientific contribution more closely than has been acknowledged in the recent literature.

Mammal and insect predation of chemically and structurally defended Mucuna holtonii (Fabaceae) seeds in a Costa Rican rain forest

2010 ◽  
Vol 26 (3) ◽  
pp. 263-269 ◽  
Author(s):  
Erin K. Kuprewicz ◽  
Carlos García-Robledo
Keyword(s):  
Seed Coat ◽  
Field Experiments ◽  
Seedling Survival ◽  
Chemical Defence ◽  
Camera Traps ◽  
Hard Seed ◽  
Seed Predators ◽  
Pecari Tajacu ◽  
Protective Strategies ◽  
Insect Predation

Abstract:To prevent seed losses from predation, plants have developed protective strategies. Seeds may utilize chemical or structural defences to deter predators. Mucuna holtonii (Fabaceae) has large seeds containing a toxic amino acid, L-dopa, and covered with a hard seed coat. Our study assessed the effectiveness of chemical and mechanical seed defences against vertebrate and invertebrate seed predators within Estación Biológica La Selva, Costa Rica. Pre-dispersal insect and fungus attack of M. holtonii seeds was low (95.7% of 1493 seeds were undamaged). Camera traps monitoring 90 marked M. holtonii seeds showed that the collared peccary (Pecari tajacu) consumed 98.6% of 69 removed seeds over 16 d. Field experiments involving 100 seeds with intact and 100 with opened seed coats found that only opened seeds had endosperm removed by Sericomyrmex amabilis ants (0.5–100% of endosperm removed). Shade-house experiments showed that seeds with high amounts of endosperm removed by ants resulted in low germination success and low seedling biomass production. Although M. holtonii seeds are rich in L-dopa, this compound is not an effective chemical defence against mammals that possess foregut fermentation. The seed coat of M. holtonii is an effective structural defence against invertebrate seed predators, preventing endosperm removal and enhancing seedling survival.

Post-dispersal losses to seed predators: an experimental comparison of native and exotic old field plants

2001 ◽  
Vol 79 (3) ◽  
pp. 284-292 ◽  
Author(s):  
C S Blaney ◽  
P M Kotanen
Keyword(s):  
Seed Predation ◽  
Seed Mass ◽  
Interspecific Variation ◽  
Experimental Comparison ◽  
Old Fields ◽  
Old Field ◽  
Seed Predators ◽  
Predator Exclusion ◽  
Reduced Rate ◽  
Insect Exclusion

Invasions by exotic plants may be more likely if exotics have low rates of attack by natural enemies, including post-dispersal seed predators (granivores). We investigated this idea with a field experiment conducted near Newmarket, Ontario, in which we experimentally excluded vertebrate and terrestrial insect seed predators from seeds of 43 native and exotic old-field plants. Protection from vertebrates significantly increased recovery of seeds; vertebrate exclusion produced higher recovery than controls for 30 of the experimental species, increasing overall seed recovery from 38.2 to 45.6%. Losses to vertebrates varied among species, significantly increasing with seed mass. In contrast, insect exclusion did not significantly improve seed recovery. There was no evidence that aliens benefitted from a reduced rate of post-dispersal seed predation. The impacts of seed predators did not differ significantly between natives and exotics, which instead showed very similar responses to predator exclusion treatments. These results indicate that while vertebrate granivores had important impacts, especially on large-seeded species, exotics did not generally benefit from reduced rates of seed predation. Instead, differences between natives and exotics were small compared with interspecific variation within these groups.Key words: aliens, exotics, granivores, invaders, old fields, seed predators.

scholarly journals Parental effects on seed mass: seed coat but not embryo/endosperm effects

1997 ◽  
Vol 84 (11) ◽  
pp. 1617-1620 ◽  
Author(s):  
Elizabeth P. Lacey ◽  
Sara Smith ◽  
Andrea L. Case
Keyword(s):  
Seed Coat ◽  
Seed Mass ◽  
Parental Effects
Sign in / Sign up

Export Citation Format

Share Document