Project description:MicroRNAs (miRNAs) and endogenous small interfering RNAs (siRNAs) play an important role in plant stress responses but the small RNA (sRNA) repertoire is poorly characterized in extremphophiles. We report sRNA transcriptomes of leaf and flower tissues of two mangrove species Bruguiera gymnorrhiza and Kandelia candel (Rhizophoraceae) based on Illumina sequencing. A total of 32 known and 5 novel miRNA families were identified collectively.Besides the conserved miR390-TAS3-ARF pathway, B. gymnorrhiza possessed additional high-abundance tasiRNAs derived from the less-conserved regions of TAS3 transcripts with expanded potential targets.his study provides the first comprehensive sRNA transcriptome for mangroves B. gymnorrhiza and K. candel. Comparative analyses revealed that these two species systematically optimize sRNA expression levels, accompanied with rewiring of sRNA regulatory networks, as an evolutionarily strategy for stress adaptations. Furthermore, 24-nt sRNAs mapped to the telomeric repeats (CCCTAAA)n were highly abundant in both B. gymnorrhiza and K. candel.
Project description:Bacterial Endophytes of Mangrove Propagules Elicit Early Establishment of the Natural Host and Promote Growth of Cereal Crops Under Salt Stress
Project description:To identify key genes in the regulation of salt tolerance in the mangrove plant Bruguiera gymnorhiza, the transcriptome profiling under salt stress was carried out. Main roots and lateral roots were collected from the mangrove plants at 0, 1, 3, 6, 12 and 24 h, 3 6 and 12 days after NaCl-treatment. Keywords: time course, stress response, root type comparison
Project description:Mangroves are salt-tolerant woody species occurring in tropical/subtropical coastal habitats. Plantation of fast-growing non-native mangrove species has been used as a tool for mangrove restoration/reforestation in several countries. However, the fast-growth ability can make recently introduced species invasive as they can possibly replace co-occurring native mangroves through expressing higher growth performance and phenotypic plasticity. Therefore, quantifying growth differences between native versus non-native mangrove species is important for forest ecology and management. In this meta-analysis, we compared the growth performance of non-native and native mangrove species pairs by analysing all available results in the literature (33 studies). We found that non-native mangrove species performed better than co-occurring native mangrove species in their introduced regions (Log response ratio?=?0.51?±?0.05) and they also expressed higher trait plasticity. Therefore, these species can be potentially invasive owing to their greater competitive advantage. However, the growth difference was diminished at higher latitudes where native mangrove species seem to perform as well as non-native mangrove species do. This is the first meta-analysis on the growth response of mangroves and it has consequential management implications. We suggest that planting of non-native mangrove species should be avoided and their spread should be monitored.
Project description:To identify key genes in the regulation of salt tolerance in the mangrove plant Bruguiera gymnorhiza, the transcriptome profiling under salt stress was carried out. Main roots and lateral roots were collected from the mangrove plants at 0, 1, 3, 6, 12 and 24 h, 3 6 and 12 days after NaCl-treatment. Samples were collected from each set of three trees at 0, 1, 3, 6, 12 and 24 h, 3 6 and 12 days after NaCl-treatment, that is 27 trees were used in total. RNA was extracted from mixture of the samples from 3 trees to average genotypes of 3 trees.
Project description:Despite an increasing recognition of the ecosystem services provided by mangroves, we know little about their role in maintaining terrestrial biodiversity, including primates. Madagascar's lemurs are a top global conservation priority, with 94 % of species threatened with extinction, but records of their occurrence in mangroves are scarce. I used a mixed-methods approach to collect published and unpublished observations of lemurs in mangroves: I carried out a systematic literature search and supplemented this with a targeted information request to 1243 researchers, conservation and tourism professionals, and others who may have visited mangroves in Madagascar. I found references to, or observations of, at least 23 species in 5 families using mangroves, representing >20% of lemur species and >50% of species whose distributions include mangrove areas. Lemurs used mangroves for foraging, sleeping, and traveling between terrestrial forest patches, and some were observed as much as 3 km from the nearest permanently dry land. However, most records were anecdotal and thus tell us little about lemur ecology in this habitat. Mangroves are more widely used by lemurs than has previously been recognized and merit greater attention from primate researchers and conservationists in Madagascar.
Project description:we used high-throughput Illumina Genome Analyzer IIx (GAIIx) technology to sequence the small RNA transcriptomes of the mangrove species, Avicennia marina. Based on sequence similarity or the secondary structure of precursors, we have identified 193 conserved miRNAs and 26 novel miRNAs in the small RNA transcriptome of Avicennia marina.
Project description:Nutrient enrichment of the coastal zone places intense pressure on marine communities. Previous studies have shown that growth of intertidal mangrove forests is accelerated with enhanced nutrient availability. However, nutrient enrichment favours growth of shoots relative to roots, thus enhancing growth rates but increasing vulnerability to environmental stresses that adversely affect plant water relations. Two such stresses are high salinity and low humidity, both of which require greater investment in roots to meet the demands for water by the shoots. Here we present data from a global network of sites that documents enhanced mortality of mangroves with experimental nutrient enrichment at sites where high sediment salinity was coincident with low rainfall and low humidity. Thus the benefits of increased mangrove growth in response to coastal eutrophication is offset by the costs of decreased resilience due to mortality during drought, with mortality increasing with soil water salinity along climatic gradients.