• Journal of Ecology and Environment
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• v.48 no.3
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• pp.308-318
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• 2024

Background: Many plants compensate for the damage caused by herbivorous insects through tolerance responses. Besides directly causing plant tissue loss and seed production reduction, herbivory causes phenological changes in the host plant. However, little is known about the fitness costs of phenological changes caused by tolerance responses to herbivorous attacks. Results: The girdling beetle Phytoecia rufiventris caused a short-term decrease in the number of flowers of the host plant Erigeron annuus. However, accelerated growth restored the number of flowers, but after a 2-week delay. With an objective to examine whether the tolerance response with such a delay fully compensates the fitness, we experimentally reproduced a 2-week delay in germination under greenhouse and field settings. Under both conditions, intraspecific competition resulted in serious defects in the growth and reproduction of E. annuus plants which of germination was delayed. However, delayed germination (DG) resulted in better growth when competition and herbivory were eliminated from the field. Thus, we showed that the tolerance response to restore reproductive production does not fully compensate for the fitness loss caused by insect attack; rather, the delay in seed production in attacked plants leads to DG and subsequent inferiority in intraspecific competition. Conclusions: Our results imply that compensation for floral production after an herbivore attack does not fully restore offspring fitness in the presence of intraspecific competition and herbivory. Assessing the ecological consequences of defense traits in an appropriate layer of interaction is critical to interpreting adaptive values.

• Korean Journal of Ichthyology
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• v.28 no.2
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• pp.87-92
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• 2016

The feeding habits of Boleophthalmus pectinirostris were studied using 198 specimens collected monthly from April 2014 to March 2015 in the intertidal zone of Beolgyo, Korea. The size of B. pectinirostris ranged from 6.5 to 18.7 cm in total length (TL, cm). B. pectinirostris was herbivore that consumes mainly centric and pennate diatoms. Its diets also included small quantities of Prorocentrum dinoflagellates. and nematods. B. pectinirostris predominantly consumed diatoms (mainly Pleurosigma spp., Navicula spp., Nitzschia spp., Gyrosigma spp.) in all fish size classes, and all months, and thus there were no significant diet changes in relation to size and month.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.113-120
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• 2020

For the conservation of both Sericinus montela (vulnerable species by red book of Korea) and A. contorta, we investigated environmental factors affecting the growth and reproduction of Aristolochia contorta. We selected four A. contorta habitats at Gapyeong, Pyeongtaek, Cheongju, and Yeoju in Korea and surveyed community and habitat characteristics of companion species, herbivore appearance, support types, and soil physicochemical properties in July and October, 2018. Habitat environments and the growth and reproduction characteristics of A. contorta were different according to four habitats of different regions. In particular, the fastest growth speed and earliest flowering and fruiting were observed in Pyeongtaek. Growth of A. contorta in Cheongju and Yeoju were interrupted by aboveground damage from human disturbance. In this study, support types seemed to be important for growth speed of A. contorta. Flowering and fruiting timing were likely to be related to combined effects of soil cation contents and competitive and herbivore stresses. Therefore, providing effective support and reducing biological stress should be necessary for stable growth and proper flowering and fruiting timing of A. contorta. In addition, experimental evidence would be needed to figure out the effect of soil cation and biological stress on flowering and fruiting of A. contorta in detail.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.3
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• pp.133-140
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• 2007

In 2006, we studied herbivore consumption rate and preference for algal species using laboratory experiments. In the no-choice feeding experiment, three herbivores (two sea urchins, Stronglyocentrotus nudus and Stronglyocentrotus intermedius and an abalone, Haliotis discus hannai) showed significantly (P<0.05) distinct preferences for four algae (Laminaria japonica, Undaria pinnatifida, Costaria costata and Ecklonia stolonifera). The alga preferred by S. nudus was L. japonica followed by U. pinnatifida, C. costata and E. stolonifera with respective daily feeding rates of $5.7{\pm}:0.85\;g,\;4.4{\pm}0.89\;g,\;3.1{\pm}0.39\;g\;and\;2.1{\pm}0.32\;g(mean{\pm}SE)$. A similar trend was found for S. intermedius. Interestingly, the herbivore consumption rates for the algae differed with or without competition. The competition stimulated the feeding activity for S. nudus, but lowered the activity for S. intermedius. The multi-choice feeding experiment confirmed that L. japonica was significantly preferred by two herbivores: S. nudus and H. discus hannai (Duncan's multiple range test, ANOVA, p<0.05).

• KSBB Journal
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• v.28 no.1
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• pp.42-47
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• 2013

This study was performed to find cellulolytic strain of enzymatic saccharification for bioethanol production. Cellulolytic strains were isolated from 59 different feces of herbivores from Seoul Grand Park located in Gwacheon Gyeonggi-Do. The celluloytic strain was selected by congo red staining and DNS method. Among the isolated strains, H9-1 strain isolated from the feces of rabbit has the highest CMCase activity. H9-1 strain was identified as Bacillus sp. based on 16S rDNA gene sequencing. The optimal conditions for CMCase activity by Bacillus sp. H9-1 were at $40^{\circ}C$ and at initial pH 8.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.113-117
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• 2015

Even though many researches are conducted for the conservation and restoration of endangered species Menyanthes trifoliata, recently, there is no study on the threatening factors to this plant. This is the first time in Korea to study growth and feeding characteristics of Deilephila elpenor as a threatening factor to Menyanthes trifoliata through an experiment. Experiment was done with 6 Eephant hawk-moth larvae and change of body weight, food preference, and ingestion amount of Bog-bean were investigated. It took 27 days from larva to pupa and maximum body weight of lavae was in the range of 4-7.5g. The food preference sequence of the lavae was Menyanthes trifoliata, Impatiens balsamina, Ampelopsis brevipedunculata var. heterophylla, Parthenocissus tricuspidata. Ingestion model shows the total amount of ingestion by a larva is 11-30g and this amount can be acquired at $0.03-0.08m^2$ of Menyanthes trifoliata pure stand. This study showed Deilephila elpenor as a potential threatening factor and suggests that the conservation and restoration plan of endangered species Menyanthes trifoliata include the control plan of Deilephila elpenor, also.

• Fisheries and Aquatic Sciences
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• v.25 no.11
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• pp.549-558
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• 2022

The Indonesian Archipelago has a very complex geological history, along with equatorial warm sea temperature, resulting in diverse types of coral reefs and high diversity of coral reef fish. Many livelihoods of the coastal community are dependent on coral reef fisheries. The present study aimed to determine which region and location in the Indonesian Archipelago has the most diverse and abundant coral reef fish. The archipelago was divided into four regions: the Indian Ocean, Sunda Shelf, Wallacea, and the Pacific Ocean. Data were obtained from a national coral reef monitoring program of the Indonesian Research Center for Oceanography (RCO)-the National Board for Research and Innovation (BRIN). The reef fish data were collected using the underwater visual census method, from 321 belt transects on 24 locations (districts) across the archipelago. The results show that coral reef fish diversity of the Pacific region was the highest across the archipelago for all three trophic levels, i.e., corallivore, herbivore, and carnivore fish. The Pacific Ocean region also had the highest fish abundance for the three trophic levels. Comparison among locations revealed that the best ten locations in reef fish diversity and abundance were Sabang, Mentawai, Makassar, Selayar, Buton, Luwuk, Ternate, Raja Ampat, Biak, and Wakatobi. Wakatobi reefs showed their supremacy in carnivore fish diversity and abundance, while Biak reefs were the best in herbivore fish. The abundance of corallivore fish was also considerably high in Sabang reefs, but it is still lower than in Raja Ampat, Biak, and Wakatobi reefs. These results provide empirical evidence that the coral reefs of Wakatobi and Biak are the hottest hotspots of coral reef fish diversity and abundance in the Indonesian Archipelago.

• Fisheries and Aquatic Sciences
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• v.26 no.4
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• pp.268-281
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• 2023

Coral reef fisheries are prominent for the archipelagic countries' food sufficiency and security. Studies showed that fish abundance and biomass are affected by biophysical variables. The present study determines which biophysical variables are important predictors of fish diversity, abundance, and biomass. The study used available monitoring data from the Indonesian Research Center for Oceanography, the National Board for Research and Innovation. Data were collected from 245 transects in 19 locations distributed across the Indonesian Archipelago, including the eastern Indian Ocean, Sunda Shelf (Karimata Sea), Wallacea (Flores and Banda Seas), and the western Pacific Ocean. Principal component analysis and multiple regression model were administered to 13 biophysical metrics against 11 variables of coral reef fishes, i.e., diversity, abundance, and biomass of coral reef fishes at three trophic levels. The results showed for the first time that the covers of other fauna, coral rubbles, and soft corals were the three most important predictor variables for nearly all coral reef fish variables. Other fauna cover was the important predictor for all 11 coral reef fish variables. Coral rubble cover was the predictor for ten variables, but carnivore fish abundance. Soft coral cover was a good predictor for corallivore, carnivore, and targeted fishes. Despite important predictors for corallivore and carnivore fish variables, hard coral cover was not the critical predictor for herbivore fish variables. The other important predictor variables with a consistent pattern were dead coral covered with algae and rocks. Dead coral covered with algae was an important predictor for herbivore fishes, while the rock was good for only carnivore fishes.

• Journal of Wetlands Research
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• v.25 no.3
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• pp.184-195
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• 2023

To develop an effective management plan for Ambrosia trifida L., an invasive alien plant in Korea, we assessed the potential of Ophraella communa LeSage as a biological control agent. This involved investigating the host specificity of the herbivore Ophraella communa LeSage, its annual travel distance, and the impact of this insect on the fitness of Ambrosia trifida L. We confirmed the host plant preference of Ophraella communa LeSage. The travel distance of this insect was determined by monitoring its appearance in selected Ambrosia trifida L. communities without these insects at distances of 10, 20, 30, and 100 meters, based on the locations where the presence of Ophraella communa LeSage was observed. The growth, reproductive, and physiological responses of Ambrosia trifida L. were measured according to feeding by Ophraella communa LeSage. As a result, Ophraella communa LeSage fed on only three taxa and moved short distances within a radius of 30 m per year from the host. The feeding behavior of the herbivore had a negative impact on the growth, reproductive, and physiological responses of Ambrosia trifida L. And the plant's growth and reproduction improved with increasing distance from the herbivore. Furthermore, the introduction of herbivores was able to control over 90% of Ambrosia trifida L. when the coverage of the Ambrosia trifida L. group was below 50%. However, the effectiveness of the removal decreased when the coverage exceeded 90%. These results are likely to be utilized by Ophraella communa LeSage as an ecological control agent. It is advantageous to introduce them in spring (May) when the coverage is low to maximize the effectiveness of control.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.326-335
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• 2007

This study was conducted to assess the environmental risks of anthracnose resistant transgenic chili peppers with the PepEST gene on non-target organisms in the agroecosystem environments during the chili pepper growing seasons in 2006. We quantitatively collected arthropods assemblages living on leaves and flowers of chili peppers on June 20, July 25, and August 25 by using an insect vacuum collector to compare the patterns of arthropod community structures between non-transgenic chili peppers (nTR, WT512) and anthracnose resistant transgenic chili peppers (TR, line 68). We found the seasonal difference with the highest species richness and Shannon's diversity in July's sampling among the growing seasons (P<0.05) and each sampling season showed the different arthropod community composition. We also found there was no statistical difference between the two types of crops, nTR and TR, at each sampling time (P>0.05). The significance level of arthropod community showed that there were lots of seasonal difference of functional groups as well as taxa but only the herbivore group in the functional groups was significantly different for the types of plants (P<0.05). So, we further examined the herbivore groups to find any potential damage and identified the possibility of herbivorous damage from some herbivores, grasshoppers, aphids and thrips. Although we couldn't find any adverse effects from the environmental risk assessment between the arthropod community structures on two types of plants from our results, we should keep working for the environmental risk assessment because of the herbivorous potential risk possibility.