Soil microbes alleviate allelopathy of invasive plants

2015 ◽  
Vol 60 (12) ◽  
pp. 1083-1091 ◽  
Author(s):  
Yang-Ping Li ◽  
Yu-Long Feng ◽  
Ya-Jun Chen ◽  
Yao-Hua Tian
2020 ◽  
Vol 11 (1) ◽  
pp. 33
Author(s):  
Enny Widyati

<p><strong>Abstrak.</strong> Seperti halnya dunia manusia, tumbuhan juga mengembangkan sistem komunikasi untuk mencapai kesejahteraan hidupnya. Bahasa yang digunakan adalah senyawa kimia yang diproduksi oleh eksudat akar. Tumbuhan merupakan inisiator karena mereka yang memiliki tujuan untuk apa komunikasi dibangun. Tumbuhan mengeluarkan eksudat akar untuk memanggil atau untuk mengusir mikroba yang diinginkan. Tumbuhan mengirim surat undangan pada beberapa mikroba dengan mensekresikan eksudat akar. Untuk membangun asosiasi mikoriza tumbuhan mengeluarkan gula, asam amino dan strigolakton. Hal tersebut akan dibalas oleh fungi dengan mengeluarkan senyawa flavonoid yang menunjukkan spesifikasi jenis inang-mikoriza. Hadirnya senyawa flavonoid merupakan undangan bagi rhizobium pada tanaman legum untuk membangun asosiasi. Tumbuhan akan menyeleksi rhizobium yang akan diajak berasosiasi dengan mensekresikan senyawa kanavanin yang bersifat toksik. Kesalahan dalam mengeluarkan eksudat akar merupakan surat undangan yang keliru bagi tumbuhan. Dosis senyawa stigolakton yang terlalu rendah tidak akan dapat membentuk asosiasi mikoriza tetapi yang berkembang adalah patogen. Walaupun tumbuhan menghasilkan senyawa fitoantisipin untuk mencegah serangan patogen dan fitoaleksin ketika patogen sudah menginfeksi. Komunikasi akar dengan akar tumbuhan lain dilakukan dengan menghasilkan senyawa alelopati untuk membatasi pertumbuhan akar di sekelilingnya yang dianggap sebagai pesaing. Tanaman invasif atau gulma umumnya selain menghasilkan alelopati juga memproduksi katekin yang dapat membunuh mikroba menguntungkan pada tumbuhan setempat. Akibatnya tumbuhan lokal akan rentan terhadap serangan penyakit dan berujung pada kematian. Selain alelopati, untuk merespon kehadiran tetangganya tumbuhan juga menghasilkan senyawa glukosinolat yang jumlahnya makin meningkat sejalan dengan tingginya biodiversitas vegetasi. Senyawa ini merupakan senyawa beracun bagi patogen, sehingga tumbuhan yang dibudidayakan dengan pola monokultur menjadi rentan terhadap penyakit. Oleh karena itu agar tanah tetap memiliki kandungan senyawa glukosinolat yang memadai serta tetap memelihara kondisi rhizosfir yang dinamis perlu dilakukan pergiliran tanaman varietas lokal setelah beberapa rotasi tanaman.</p><p><em><strong>Abstract.</strong> Similar to human, plants also develop a communication system to achieve their prosperity. Plants utilize chemical compounds of their root exudates as the “languange”. Plants are the initiator of communications, since they define the purposes of building communication. Root exudates are released either to attract or to demenish the soil microbes target as an “invitation letter” to some microbes. To build a mycorrhizal association, for examples, plants issue sugars, amino acids and strygolactones to the rhizosphere. Fungi will reply the invitation by secreting flavonoid compounds that determine host-mycorrhizal specifications. The presence of flavonoids is another invitation to rhizobia to establish association in legume rhizosphere. Plants will select attracted bacteria to build the most host-specific rhizobium association by secreting canavanine compounds that are toxic to non-target rhizobia. Occasionally, an error happened in issuing invitation. When plant release strygolactone in a very low dosages, it will be failure to build mycorrhizal associations otherwise pathogen colonizations, although plants produce either phytoantisipine to prevent pathogens infection or phytoalexin to counter infected pathogens. Communication among roots of neighboring plants is conducted by producing allellopathy compound to limit root growth of the competitors. Invasive plants or weeds generally also produce catechine compounds over the allellophaty that will eliminate soil beneficial microbes of the indigenous plants. As a result, the native plants will be vulnerable to disease and lead to distinct. Responding to the presence of neighboring roots, plants also produce glucosinolate compounds. Glucocynolate consentration will be increased in line with the richness of vegetation biodiversity. These compounds are toxic to the pathogen, which is why plants cultivated in monoculture become more susceptible to disease. Furthermore, to improve soil glucocynolate and to manage the dynamics in the rhizosphere, need to a shift cultivation after several rotations of a commodity with the local varieties.</em></p>


2021 ◽  
Author(s):  
Yongge Yuan ◽  
Huifei Jin ◽  
Junmin Li

Abstract Aims There is an increasing likelihood that invasive plants are again exposed to their co-evolved specialist herbivores in the non-native range. However, whether there is a latitudinal pattern associated with the resistance of an invasive plant to its co-evolved herbivores and how soil microbes affect resistance has been little explored. We hypothesized that the resistance of invasive Solidago canadensis to its co-evolved insect herbivore Corythucha marmorata could increase with latitude, and that local rhizosphere microbes could facilitate invasive plants to become resistant to their co-evolved herbivores. Methods We conducted a field survey and a greenhouse experiment to examine whether there was a latitudinal pattern in the abundance of C. marmorata and in the damage it caused to S. canadensis in China. We tested whether local rhizosphere microbes of invasive plants can promote the resistance of S. canadensis to C. marmorata herbivory. Important findings In the field survey, both density of C. marmorata and damage level of S. canadensis were positively correlated with latitude, and with S. canadensis plant growth, indicating a latitudinal pattern in the resistance of S. canadensis to C. marmorata. However, in the greenhouse experiment, S. canadensis from different latitudes did not suffer significantly from different levels of damage from C. marmorata. Additionally, the damage level of S. canadensis was lower when rhizosphere soil and rhizomes originated from field S. canadensis with same damage level than with different damage levels. This result indicates that local rhizosphere soil microbes promote the adaptation of S. canadensis to resistance of C. marmorata.


2021 ◽  
Author(s):  
Hanxia Yu ◽  
Johannes J. Le Roux ◽  
Mengxin Zhao ◽  
Weihua Li

Abstract Background and aims Allelopathy is frequently invoked as being important for successful invasion by non-native plants. Yet, the effects of specific phytochemicals of invasive plants on soil microbes remain unexplored. Methods Here we used manipulative experiments and next generation sequencing (NGS) approaches to investigate how the sesquiterpene lactones (STLs) of invasive Mikania micrantha influence soil microbial communities and nutrients.Results We found Mikania STLs to significantly increase the regulation of soil microbial activity (i.e. increased CO2 concentrations). Using the specific STL, dihydromikanolide, we found available soil nutrients to increase in the presence of this phytochemical and that bacterial richness increased while fungal richness decreased. The presence of dihydromikanolide also increased the abundance of beneficial soil bacteria and fungi associated with nutrient cycling and supply, while simultaneously lowering pathogen abundance. Clustering analysis found bacterial functional groups, such as those involved in carbon, nitrogen, phosphorus, and sulfur metabolism, to be similar in experimentally-treated dihydromikanolide soils and Mikania-invaded soils collected from the field, but significantly higher than those in uninvaded soils. This suggests that M. micrantha can enhance certain bacterial functional groups via its phytochemicals. Soil fungi, on the other hand, appeared to be less sensitive to dihydromikanolide than bacteria. Conclusions We conclude Mikania STLs, and in particular dihydromikanolide, may be key factors in determining soil microbial structure and function and may contribute to the invasion success of the species. Our findings provided a new perspective for understanding the effects of invasive plants on soil microbial communities via their impacts through phytochemicals.


2019 ◽  
Vol 37 ◽  
pp. 188-196
Author(s):  
Antonio Ruiz de Gopegui ◽  
Yolanda Ruiz

Contributions to the Palencia’s Mountain flora and its influence area. Palabras clave. Corología, flora amenazada, flora invasora, Palencia, España. Key words. Chorology, Endangered plants, Invasive plants, Palencia, Spain.


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