| Plants and insect herbivores are integral to the forest ecosystem, playing important roles in food webs, nutrient cycling and energy transfer. Herbivory on leaves by insect is common in the forest, and plants have consequently developed multiple strategies against insect herbivores. The evolutionary relationship between herbivores and plants has resulted in an impressive variety of adaptations and interactions, and studies of that relationship have become a most interesting focus in evolutionary biology and ecology.Evergreen broad-leaved forest is the regional vegetation in eastern China, and differs from tropical and temperate forest in both species diversity and community structure. Although research into subtropical evergreen broad-leaved forest had been conducted from many perspectives, study of the interaction between plant and insect herbivores is rare. However, the interaction between plants and herbivores is very important for maintaining and restoring evergreen broad-leaved forest. In this study, plants in Mt. Meihuashan of Fujian province and the Tiantong region of Zhejiang province were investigated. Through field research, monitoring and data analyses in the lab, herbivory pattern diversity, leaf phenology, leaf traits, temporal and spatial patterns of herbivory were researched into. And the strategies plants used to battle herbivores were summarized according to the results, which are as follows: 1 The study investigated herbivory patterns on leaves of 11 evergreen plant species in Tiantong National Forest Park. As a result, (1) 16 kinds of insect herbivory patterns were identified on the leaves of 11 evergreen tree species, and from 10 to 13 for leaves from the same species. The frequency of Edge Defoliation was the highest (28.7%) and that of Gall was the lowest (0.5%). (2) Based on the number of dominant insect herbivory patterns in a species, three distribution types in 11 species were identified: (i) mono-dominant distribution-type with only one dominant insect herbivory pattern in a species(Rhododendron ovatum and Loropetalum chinense); (ii) bi-dominant distribution-type with two dominant insect herbivory patterns in a species(Schima superba); and (iii) multi-dominant distribution-type with three ormore than three dominant insect herbivory patterns in other 8 tree species. (3) Although the average index of six arbor species (2.040) was higher than that of five shrub species (1.882) and the average index of dominant species was higher than that of companion species, there was no significant difference between them. (4) Correlation analysis showed that there were significantly positive correlations among eight pairs of insect herbivory patterns and significantly negative correlation among four pairs of insect herbivory patterns. This may suggest similarity and difference in insect herbivory selection.2 The dynamics of herbivory on 11 plants was investigated in Tiantong, Zhejiang province. The results were as follows: (1) Average herbivory on plant leaves was 11.87%, and 56.9% of herbivory occurred during leaf expansion. Herbivory frequency was 50.15%, and 62.30% of herbivory frequency occurred during leaf expanison. (2) Herbivory patterns could be classified into three categories according to the herbivory intensity in different seasons: mono-peak herbivory pattern with leaf damage occurring mainly in spring (Eurya muricala , Castanopsis fargesii and C. sclerophylla); bi-peak herbivory pattern with leaf damage occurring not only in spring but also in summer (Castanopsis carlesii, Cyclobalanopsis glauca, Camellia fraternal and Rhododendron ovatum); tri-peak herbivory pattern with damage occurring in spring, summer and autumn (Schima superba). (3) Life form affected herbivory on leaves. Herbivory on arbors leaves was significantly higher (18.66%) than that on shrubs (6.21%; t=2.260, p=0.050). Although herbivory on leaves of dominant species (13.00%) was higher than companion species (10.51%), there was no significant difference between them (p>0.05).3 As indicated by the Mt. MeiHuaShan and Tiantong monitoring project, herbivory during the leaf expansion period can be classified into 3 categories according to time: (1) Pre-herbivory, meaning the majority of herbivories occurred before the leaves reached full size; (2) Post-herbivory, meaning the majority of herbivory occurred in several days after the leaves reached full size; and (3) mid-herbivory, that is, herbivory occurred during leaf expansion and development. The patterns of herbivory on young leaves were the results of strategies applied by plants. Plants that sufferedpre-herbivory damage might employ "escape" strategy to reduce leaf losses. Plants that suffered post-herbivory damage might employ 'defense' strategy to reduce leaf losses. Nonetheless, plants of the mid-herbivory pattern depend on other factors or employ both strategies.4 The effects of habitat on herbivory in juveniles of Schima superba was investigated in Tiantong. The results suggested, (1) for shade leaves, the rates of herbivory were significantly higher (14.14%) in S. superba than that in bamboo forest (5.71%; p<0.05). However, in 5. superba forest, herbivory on leaves showed no significant difference between in shade (12.28%) and in light gap (14.72%). (2) for the majority of damaged leaves, leaf area losses were under 10%. It means that herbivory was moderate rather than serious as assumed before. (3) There was a significantly positive correlation between herbivory and herbivory frequency.5 Timing of leaf emergence, leaf expansion rate, duration of leaf expansion, leaf emergence pattern and herbivory on young leaves were investigated in Mt. MeiHuaShan. The relationships between leaf phenology and leaf herbivory were examined. The results were as follows: (1) Herbivory on young leaves was 8.59% and herbivory frequency was 33.29%. (2) 82% of the species leafed out in April and there was no significant difference on leaf emergence time between arbors and shrubs. No significant correlation was found between the timing of leaf emergence and herbivory on young leaves. There was significant correlation between leaf expansion rate and leaf emergence time (R=0.38, p<0.05). The earlier the species leafed out, the slower it expanded. The leaf expansion rate of arbors was significantly more rapid than that of shrubs (t=2.196, p<0.05). Significant relationship was found between leaf expansion rate and herbivory on young leaves (R=0.35, p=0.039). The more rapid the leaves expanding, the greater damage it suffered. (3) In terms of synchrony of leafing out, there was no significant difference between arbors and shrubs. There was no significant correlation between synchrony of leafing out and herbivory on young leaves, but significant relationship was found between it and herbivory frequency (R=0.35, p=0.030). It means the more synchronous the species leafed out, the more leaves were attacked. (4) Duration of leaf expansion differed by almost 60 days andwere significantly related to leaf expansion rate (R=-0.423, p=0.008). However, no significant relationship was found between duration of leaf expansion and herivory on young leaves.6 To study the effects of leaf traits on herbivory, chlorophyll content, water content, LMA (Leaf mass per area) and leaf toughness of young leaves and herbivory were studies in Mt. Meihuashan. The relationship between leaf traits and herbivory was examined. The results were as follows: (1) Chlorophyll content was significantly negatively correlated with LMA (p<0.001) and leaf toughness (p=0.012), and LMA was significantly positively correlated with leaf toughness (p<0.001). (2) Herbivory was significantly positively related to water content (p=0.034). However, no significant correlations were found between herbivory and chlorophyll, LMA and leaf toughness. (3) The herbivory on young leaves of 77% of the species examined was positively correlated with water content, and it was significant for Lithocarpus synbalanus, Castanopsis sclerophylla, Schima superba, Castanopisis eyrei and Camellia fraterna. The herbivory on young leaves of 73% of all species was negatively correlated with LMA, and it was significant for Lithocarpus synbalanus, Castanopsis sclerophylla and Schima superba. (4) The herbivory of 68% of all species was negatively correlated with leaf toughness, and it is significant for Lithocarpus synbalanus, Castanopsis carlesii, Cyclobalanopsis glauca and S. superba. However, herbivory on the leaves of Machilus oreophila was positively correlated with leaf toughness. Herbivory was not significantly related to chlorophyll content. For mature leaves, herbivory was not significantly correlated with leaf toughness. Herbivory on mature leaves was negatively correlated with LMA, but it was significant only for Rhododendron ovatum and Camellia fraterna. And herbivory was also negatively correlated with chlorophyll content, but it was significant only for Cyclobalanopsis glauca, S. superba and Camellia fraterna. However, herbivory on mature leaves was positively correlated with water content, and it was significant for Eurya weissiae and Eurya nitida. (5) Significant relationship was found between herbivory and herbivory frequency (p=0.004) on mature leaves.7 Three strategies were identified according to the results mentioned above. (1) Thespecies that leafed out earlier with lower leaf water content, higher leaf toughness and lower leaf expansion rate, such as Cinnamomum porrectum, C. tsangii and Adinandra millettii, might employ 'defense' strategy to reduce leaf losses. (2) The species that leafed out later with higher leaf water content, lower leaf toughness and higher leaf expansion rate, such as Lithocarpus synbalanus, Castanopsis sclerophylla, Schima superba and Castanopisis eyrei, might employ 'escape' strategy to reduce herbivory. (3) The strategies used by other species are not clear and they might employ either of the two strategies or other ways to reduce herbivory.
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