scholarly journals Diversity of endophytic bacteria from Citrus and Inga trees in the coffee agro-ecosystem and fluctuations by location, shade management and season

2017 ◽  
Vol 101 (2) ◽  
pp. 165-184
Author(s):  
Carlos Bolaños-Carriel ◽  
Mildred Zapata ◽  
Linda Wessel-Beaver ◽  
Brent V. Brodbeck ◽  
Peter C. Andersen

Coffee, Coffea arabica L., is planted in diverse agro-ecological environments in the mountains of Puerto Rico (PR). The pathogen, Xylella fastidiosa Wells et al., is a xylem-limited phytopathogenic bacterium transmitted by insects that causes coffee leaf scorch, citrus-variegated chlorosis and vascular diseases of many other plant species. The objective of this study was to characterize the fastidious endophytes occupying a similar niche as X. fastidiosa in the vascular system of Citrus sinensis and Inga vera trees in low diversity and high diversity shade environments where coffee is grown In PR. Sampling was conducted over two years in four localities: Adjuntas, Jayuya, Las Marías and Yauco during the dry and rainy seasons. Citrus sinensis and Inga vera were generally the only shade treesin coffee plantations described as "low diversity"; in "high diversity" plantations these same species were present along with Pithocellobium carbonarium, Gliricidia sepium and Andira inermis. Endophyte population (EP) and endophyte diversity (ED) were contrasted using factorial arrangements of shade, locality, season and year. Endophytes were clustered using multivariate analysis. Neither shade nor season had an effect on EP in Citrus. In Inga vera, EP was about three times higher in the second year compared to the first year regardless of season, location or shade. In both Citrus and Inga, ED was low. The highest ED was detected in Jayuya and the lowest in Las Marías. Ward's algorithm combined Citrus and Inga fastidious strains into four and five clusters for Gram-negative and Gram-positive bacteria, respectively. Endophyte diversity of Citrus and Inga was determined by the plant species, not by location or shade. However, ED was higher in shaded coffee with low diversity of tree species. Thus, effects of shade (low versus high diversity) altered the community structure of endophytes prevalent in the vascular tissue and may impact host plant resistance to pathogens such as X. fastidiosa.

2009 ◽  
Vol 6 (2) ◽  
pp. 3187-3214 ◽  
Author(s):  
A. Weigelt ◽  
W. W. Weisser ◽  
N. Buchmann ◽  
M. Scherer-Lorenzen

Abstract. Modern grassland management seeks to provide many ecosystem services and experimental studies in resource-poor grasslands have shown a positive relationship between plant species richness and a variety of ecosystem functions. Thus, increasing species richness might help to enhance multifunctionality in managed grasslands if the relationship between species richness and ecosystem functioning is equally valid in high-input grassland systems. We tested the relative effects of low-input to high-input management intensities and low to high plant species richness. Using a combination of mowing frequencies (1, 2 or 4 cuts per season) and fertilization levels (0, 100 and 200 kg N ha−1 a−1), we studied the productivity of 78 experimental grassland communities of increasing plant species richness (1, 2, 4, 8 or 16 species with 1 to 4 functional groups) in two successive years. Our results showed that in both years higher diversity was more effective in increasing productivity than higher management intensity: the 16-species mixtures had a surplus of 452 g m−2 y−1 in 2006 and 504 g m−2 y−1 in 2007 over the monoculture yields whereas the high-input management resulted in only 315 g m−2 y−1 higher productivity in 2006 and 440 g m−2 y−1 in 2007 than the low-input management. In addition, high-diversity low-input grassland communities had similar productivity as low-diversity high-input communities. The slopes of the biodiversity – productivity relationships significantly increased with increasing levels of management intensity in both years. We conclude that the biological mechanisms leading to enhanced biomass production in diverse grassland communities are as effective for productivity as a combination of several agricultural measures. Our results demonstrate that high-diversity low-input grassland communities provide not only a high diversity of plants and other organisms, but also ensure high forage yields, thus granting the basis for multifunctional managed grasslands.


2019 ◽  
Vol 7 (2) ◽  
pp. 174
Author(s):  
Zainal Arifin Wazaraka ◽  
Edoward K. Raunsay ◽  
Konstantina M. B. Kameubun

The existence of cendrawasih (Paradisaea minor jobiensis Rothschild 1897) has been endangered due to destruction its habitats and wild hunting, hence conservation of its habitats is urgently needed. The objective of this study was to determine the availability of vegetation materials for creating the nests as an effort for the conservation of P. minor jobiensis in Imboriawi Forest, Barawai, Yapen Islands, Papua. Data were collected using the method of line compartment. Vegetation at seedling, sapling, pole and tree levels were measured and analyzed to determine the availability of plant species as the materials for creating bird nest. The results of vegetation analysis revealed 60 species at seedling level, 43 species at sapling level, 68 species at pole level, and 74 species at tree level with high diversity index values (H’) of 3.68, 3,32, 3,87, and 3,87 for seedling, sapling, pole, and tree levels, respectively. The results also revealed that vegetation used as a materials of nest of P. minor jobiensis in Imbowiari Forest is Bidens spilosa, Macaranga mappa, Timonius timon and Ficus septica. The four species at seedling, sapling, poles, and tree levels have low diversity index values (H’= 1) but can be used as indicators of making a nest in a sustainable way. Keywords: bird nest, conservation, Paradisaea minor jobiensis, vegetation analysis


2009 ◽  
Vol 6 (8) ◽  
pp. 1695-1706 ◽  
Author(s):  
A. Weigelt ◽  
W. W. Weisser ◽  
N. Buchmann ◽  
M. Scherer-Lorenzen

Abstract. Modern grassland management seeks to provide many ecosystem services and experimental studies in resource-poor grasslands have shown a positive relationship between plant species richness and a variety of ecosystem functions. Thus, increasing species richness might help to enhance multifunctionality in managed grasslands if the relationship between species richness and ecosystem functioning is equally valid in high-input grassland systems. We tested the relative effects of low-input to high-input management intensities and low to high plant species richness. Using a combination of mowing frequencies (1, 2 or 4 cuts per season) and fertilisation levels (0, 100 and 200 kg N ha−1 a−1), we studied the productivity of 78 experimental grassland communities of increasing plant species richness (1, 2, 4, 8 or 16 species with 1 to 4 functional groups) in two successive years. Our results showed that in both years higher diversity was more effective in increasing productivity than higher management intensity: the 16-species mixtures had a surplus of 449 g m−2 y−1 in 2006 and 492 g m−2 y−1 in 2007 over the monoculture yields whereas the high-input management resulted in only 315 g m−2 y−1 higher productivity in 2006 and 440 g m−2 y−1 in 2007 than the low-input management. In addition, high-diversity low-input grassland communities had similar productivity as low-diversity high-input communities. The slopes of the biodiversity – productivity relationships significantly increased with increasing levels of management intensity in both years. We conclude that the biological mechanisms leading to enhanced biomass production in diverse grassland communities are as effective for productivity as a combination of several agricultural measures. Our results demonstrate that high-diversity low-input grassland communities provide not only a high diversity of plants and other organisms, but also ensure high forage yields, thus granting the basis for multifunctional managed grasslands.


2010 ◽  
Vol 17 (1) ◽  
pp. 17-30 ◽  
Author(s):  
Katarzyna J. Chwedorzewska

ABSTRACTThe geographic position, astronomic factors (e.g. the Earth’s maximum distance from the Sun during winter), ice cover and altitude are the main factors affecting the climate of the Antarctic, which is the coldest place on Earth. Parts of Antarctica are facing the most rapid rates of anthropogenic climate change currently seen on the planet. Climate changes are occurring throughout Antarctica, affecting three major groups of environmental variables of considerable biological significance: temperature, water, UV-B radiation.Low diversity ecosystems are expected to be more vulnerable to global changes than high diversity ecosystems


Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1047
Author(s):  
Gianni Bellocchi ◽  
Catherine Picon-Cochard

Associated with livestock farming, grasslands with a high diversity of plant species are at the core of low-input fodder production worldwide [...]


ENTOMON ◽  
2021 ◽  
Vol 46 (4) ◽  
pp. 279-284
Author(s):  
S. Barathy ◽  
T. Sivaruban ◽  
Srinivasan Pandiarajan ◽  
Isack Rajasekaran ◽  
M. Bernath Rosi

In the study on the diversity and community structure of Ephemeroptera in the freshwater stream of Chinnasuruli falls on Megamalai hills, a total of 523 specimens belonging to thirteen genera and five families were collected in six month periods. Of the five families, Teloganodidae and Leptophlebiidae exhibited high diversity and Caenidae showed low diversity. Choroterpes alagarensis (Leptophlebiidae) is the most dominant species. Diversity indices such as Shannon and Simpson indices showed that diversity was maximum in November and December and it was minimum in August and January. Canonical Correspondence Analysis revealed that rainfall, water flow, turbidity, and air temperature were the major stressors in affecting the Ephemeropteran community structure.


Trees ◽  
2018 ◽  
Vol 33 (1) ◽  
pp. 171-182 ◽  
Author(s):  
Jing-Hao Huang ◽  
Jing Xu ◽  
Xin Ye ◽  
Tu-Yan Luo ◽  
Li-Hua Ren ◽  
...  

2018 ◽  
Vol 7 (1) ◽  
Author(s):  
Yanieta Arbiastutie ◽  
Djoko Marsono ◽  
Wahyuningsih MSH ◽  
Rishadi Purwanto

Diversity of biological resources in primary forest is not only limited to the woody plant species, but also covered by underground plant which has diverse species high diversity. This underground plant as one part of the forest ecosystem is a plant that has potential as a medicine. The study aims to conduct an inventory of underground plant species in Gunung Gede Pangrango National Park West Java Province. The method for inventory used spasial analysis with land management unit and multi stage sampling. The spasial analysis used three categories, first the zonation map, second the soil characterization map and the third altitude map. The LMU consist of 6 areas with total plot number 60. The results showed there are 83 species underground plant consist of 45 family. The family consist of Acanthaceae, Annonaceae, Apiaceae, Apocynaceae, Araceae, Araliaceae, Aspleniaceae, Asteraceae, Balsaminaceae, Begoniaceae, Compositae, Convolvulaceae, Cucurbitaceae, Cyperaceae, Elaeagnaceae, Equisetaceae, Fabaceae, Gesneriaceae, Gramineae, Hypoxidaceae, Lamiaceae, Malvaceae, Marattiaceae, Melastomataceae, Menispermaceae, Moraceae, Musaceae, Myrsinaceae, Oxalidaceae, Passifloraceae, Piperaceae, Plantaginaceae, Polygalaceae, Primulaceae, Rosaceae, Rubiaceae, Sellagineaeeae, Smilaceae, Solanaceae, Symplocaceae, Urticaceae, Verbenaceae, Woodsiaceae, Zingiberaceae. The underground plant has a potential as medicinal plant.Keywords: Gunung Gede Pangrango National Park, inventory, land management unit, medicinal plant, underground plant


2021 ◽  
Vol 8 ◽  
Author(s):  
Yaoyao Cai ◽  
Haipeng Yao ◽  
Zhen Sun ◽  
Ying Wang ◽  
Yunyun Zhao ◽  
...  

Nuclear factor of activated T cells (NFAT) is a transcription factor with a multidirectional regulatory function, that is widely expressed in immune cells, including cells in the cardiovascular system, and non-immune cells. A large number of studies have confirmed that calcineurin/NFAT signal transduction is very important in the development of vascular system and cardiovascular system during embryonic development, and plays some role in the occurrence of vascular diseases such as atherosclerosis, vascular calcification, and hypertension. Recent in vitro and in vivo studies have shown that NFAT proteins and their activation in the nucleus and binding to DNA-related sites can easily ɨnduce the expression of downstream target genes that participate in the proliferation, migration, angiogenesis, and vascular inflammation of vascular wall related cells in various pathophysiological states. NFAT expression is regulated by various signaling pathways, including CD137-CD137L, and OX40-OX40L pathways. As a functionally diverse transcription factor, NFAT interacts with a large number of signaling molecules to modulate intracellular and extracellular signaling pathways. These NFAT-centered signaling pathways play important regulatory roles in the progression of atherosclerosis, such as in vascular smooth muscle cell phenotypic transition and migration, endothelial cell injury, macrophage-derived foam cell formation, and plaque calcification. NFAT and related signaling pathways provide new therapeutic targets for vascular diseases such as atherosclerosis. Hence, further studies of the mechanism of NFAT in the occurrence and evolution of atherosclerosis remain crucial.


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