scholarly journals Selection of Phylloplane and Endophyte Microbes as Biocontrol for Rubber Leaf Fall Disease (Corynespora cassiicola)

2018 ◽  
Vol 5 (3) ◽  
pp. 113
Author(s):  
Khaerati Khaerati ◽  
Yulius Ferry ◽  
Rusli Rusli

<p><em>Leaf fall disease in rubber caused by </em>Corynespora cassiicola<em> </em><em>fungi significantly decreases rubber productivity. </em>C. cassiicola<em> causes leaves to fall all year round</em><em>,  a delay in the tapping of immature rubber  plants, yield decrease of producing plants, and even death of susceptible clones.  The study aimed to obtain phylloplane and endophytic microbes potentially to inhibit the disease, was conducted from January to December 2016. The study used randomized complete design to assess antagonistic fungi and phylloplane and endophytic bacterias toward </em>C. cassiicola<em> in isolates obtained through exploration in </em><em>West Java and West Kalimantan. Pathogen isolation showed </em>Corynespora sp<em> with pale brown color, single conidia which slightly bended, shaped like a stick that is swollen at the base, with 2–14 septa.  Inhibitory analysis found 42 fungi isolates and 19 bacteria isolates potentially inhibiting </em>C. cassiicola<em>. </em><em>Six fungi isolates have an inhibitory ability of ≥90%, consisting of two phylloplane fungi isolates (DTJF11 and CPSR7) and four endophytic fungi (CEBPM15, CEBPM23, CEBPM27, and CEPR9) with lysis, mycoparasitism, competition, and antibiosis inhibitory mechanism. The identification showed fungi isolate of DTJF11 is classified as  </em>Trichoderma asperellum<em>, CPSR7 as </em>Talaromyces pinophilus<em>, and CEBPM15</em><em> as </em>Amanita tenuifolia<em>.  </em><em>Potential bacterial isolates as biological agents are BP7, L3, BP3, BP4, BP5 and BP6 isolates, which have inhibitory power of 28.54%–40.94%, with antibiosis inhibition mechanism.</em></p>

2021 ◽  
Vol 7 (6) ◽  
pp. 485
Author(s):  
Boxun Li ◽  
Yang Yang ◽  
Jimiao Cai ◽  
Xianbao Liu ◽  
Tao Shi ◽  
...  

Rubber tree Corynespora leaf fall (CLF) disease, caused by the fungus Corynespora cassiicola, is one of the most damaging diseases in rubber tree plantations in Asia and Africa, and this disease also threatens rubber nurseries and young rubber plantations in China. C. cassiicola isolates display high genetic diversity, and virulence profiles vary significantly depending on cultivar. Although one phytotoxin (cassicolin) has been identified, it cannot fully explain the diversity in pathogenicity between C. cassiicola species, and some virulent C. cassiicola strains do not contain the cassiicolin gene. In the present study, we report high-quality gapless genome sequences, obtained using short-read sequencing and single-molecule long-read sequencing, of two Chinese C. cassiicola virulent strains. Comparative genomics of gene families in these two stains and a virulent CPP strain from the Philippines showed that all three strains experienced different selective pressures, and metabolism-related gene families vary between the strains. Secreted protein analysis indicated that the quantities of secreted cell wall-degrading enzymes were correlated with pathogenesis, and the most aggressive CCP strain (cassiicolin toxin type 1) encoded 27.34% and 39.74% more secreted carbohydrate-active enzymes (CAZymes) than Chinese strains YN49 and CC01, respectively, both of which can only infect rubber tree saplings. The results of antiSMASH analysis showed that all three strains encode ~60 secondary metabolite biosynthesis gene clusters (SM BGCs). Phylogenomic and domain structure analyses of core synthesis genes, together with synteny analysis of polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) gene clusters, revealed diversity in the distribution of SM BGCs between strains, as well as SM polymorphisms, which may play an important role in pathogenic progress. The results expand our understanding of the C. cassiicola genome. Further comparative genomic analysis indicates that secreted CAZymes and SMs may influence pathogenicity in rubber tree plantations. The findings facilitate future exploration of the molecular pathogenic mechanism of C. cassiicola.


2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Engy Elekhnawy ◽  
Fatma Sonbol ◽  
Ahmed Abdelaziz ◽  
Tarek Elbanna

Abstract Background Antibiotic resistance in pathogenic bacterial isolates has increased worldwide leading to treatment failures. Main body Many concerns are being raised about the usage of biocidal products (including disinfectants, antiseptics, and preservatives) as a vital factor that contributes to the risk of development of antimicrobial resistance which has many environmental and economic impacts. Conclusion Consequently, it is important to recognize the different types of currently used biocides, their mechanisms of action, and their potential impact to develop cross-resistance and co-resistance to various antibiotics. The use of biocides in medical or industrial purposes should be monitored and regulated. In addition, new agents with biocidal activity should be investigated from new sources like phytochemicals in order to decrease the emergence of resistance among bacterial isolates.


2021 ◽  
Vol 17 (2) ◽  
pp. 189-195
Author(s):  
TR Setyawati ◽  
AH Yanti ◽  
R. Kurniatuhadi

The bacterial isolates NrLtF1, NrLtF4, NrLtF5, and NrLtG2 isolated from fecal pellets and gastrointestinal tract of nypha worms (Namalycastis rhodochorde) have cellulolytic, proteolytic activity and produce organic acids. The four isolates have the potency to be developed as probiotics in nypha worm cultivation feed. This study aims to determine the probiotics potency and identify the species of NrLtF1, NrLtF4, NrLtF5, and NrLtG2 isolate based on 16srDNA sequence. The probiotic potency was carried out by the acid tolerance assays on distilled water and 0.3% acid bile media, and the antimicrobial testing against Escherichia coli (MF exp21.12). Bacterial identification was carried out by sequencing of 16sDNA sequence based on GeneBank data. The results showed that the bacterial isolates of NrLtF1, NrLtF4, NrLtF5, and NrLtG2 were able to grow on 0.3% distilled water and acid bile media. However, only the NrLtF4 and NrLtF5 inhibited E. coli (MF exp21.12) with halo zones 30 mm and 18 mm, respectively. Blasting results of the 16srDNA sequences showed that the NrLtF1, NrLtF4, NrLtF5, and NrLtG2 were closely related to Bacillus wiedmannii, Brevibacterium sediminis, Bacillus proteolyticus, and Bacillus paramycoides. The nypha worm bacterial isolates have the potency to be developed as probiotics in nypha worm culture.


2019 ◽  
Vol 18 (4) ◽  
pp. 51-61
Author(s):  
Phong X. Huynh

The objectives of this study were to investigate the change of microorganisms involved in cocoa (Theobroma cacao) fermentation and then to isolate, characterize and select the important microorganisms in cocoa fermentation. The results showed that microbial quantities continuously changed during cocoa fermentation and the highest quantity of dominant microorganisms at different stages of fermentation process as 8.03 log cfu/g of yeast, 6.34 log cfu/g of mold, 7.77 log cfu/g of lactic acid bacteria, 7.87 log cfu/g of acetic acid bacteria, 7.25 log cfu/g of Bacillus, and 10.93 log cfu/g of the total aerobic bacteria. There were nine yeast isolates belonging 5 genera of Saccharomyces, Kluyveromyces, Brettanomyces, Candida and Cystofilobasidium; 9 mould isolates belonging to 2 genera of Rhizopus and Aspergillus; 11 acetic acid bacteria isolates belonging to Acetobacter; and 13 spore-forming bacterial isolates belonging to Bacillus isolates. Three isolates of yeast (CY-1a, CY-1b, CY-2a) belonging to Kluyveromyces possessed the high fermentative capacity and 4 Acetobacter isolates (CAAB-1d, CAAB-1a, CAAB-1e and CAAB-2d) produced high amounts of acetic acid.


2006 ◽  
Vol 27 (7) ◽  
pp. 682-687 ◽  
Author(s):  
Shawn Binkley ◽  
Neil O. Fishman ◽  
Lori A. LaRosa ◽  
Ann Marie Marr ◽  
Irving Nachamkin ◽  
...  

Objective.To identify differences between unit-specific and hospital-wide antibiograms and to determine the potential impact of these differences on selection of empirical antimicrobial therapy.Setting.A 625-bed tertiary care medical center.Methods.Antimicrobial susceptibility results were collected for all inpatient clinical bacterial isolates recovered over a 3-year period; isolates were categorized by the hospital location of the patient at the time of sampling and by the anatomic site from which the isolate was recovered. Antibiograms from each unit were compiled for the most commonly isolated organisms and were compared to the hospital-wide antibiogram.Results.A total of 9,970 bacterial isolates were evaluated in this study, including 2,646 enterococcal isolates, 2,806 S. aureus isolates, 2,795 E. coli isolates, and 1,723 Pseudomonas aeruginosa isolates. The percentages of bacterial isolates resistant to antimicrobials were significantly higher in the medical ICU and surgical ICU than the hospital-wide antibiogram would have predicted, whereas the percentages of isolates susceptible to antimicrobials were significantly higher in the non-ICU units, compared with the hospital overall. However, on general medicine units, the prevalence of susceptibility to levofloxacin was significantly lower than that for the hospital overall.Conclusions.Unit-specific antibiograms are important for making informed decisions about empirical antimicrobial therapy, because the hospital-wide antibiogram may mask important differences in susceptibility rates across different units. These differences may have important implications for selecting the optimal empirical antimicrobial therapy.


2018 ◽  
Vol 9 ◽  
Author(s):  
David Lopez ◽  
Sébastien Ribeiro ◽  
Philippe Label ◽  
Boris Fumanal ◽  
Jean-Stéphane Venisse ◽  
...  

2011 ◽  
Vol 8 (1) ◽  
pp. 63-70
Author(s):  
Nurhayati Nurhayati ◽  
Aron Situmorang

Effect of weather on the development of leaf fall disease in the yielding rubber estate.  This research was conducted in  PTP VII Bergen Lampung  from  July  to August for 2005 and 2006 (new leaves period). This research was carried out using survey and experiment methods.  Parameters observed in the research were persentages of leaf stage, the number of leaf fall  per m2 caused by Corynespora cassiicola and amount of  spore distributed  in air, daily rainfall amount and number of rain days. Results of the study showed that  the pattern of rainfall  and number of raindays affected the development of plant’s new  leaves and  leaf fall disease caused by Corynespora.  The amount of spores distributed in the air was relatively higher in 2005 observation period compared to  2006 one.  The pattern of rainfall and number of rain days also affected the disease severity which was higher in 2005 compared to 2006. Epidemy  was occurred when lower rainfall amount  taking place intermittently with sunny days in the period of new leave formation.


2020 ◽  
Vol 5 (2) ◽  
pp. 84-90
Author(s):  
Vira Ruainiah Ruswandari ◽  
Ahmad Syauqi ◽  
Tintrim Rahayu

  Trichoderma viride is a microorganism that is commonly found in moist soil and can be isolated from the root area of the shallot plant (Allium ascalonicum L.). The study aim was to determine the mechanism and the difference in percentage of inhibitory power by Trichoderma viride in inhibiting growth of Alternaria porri pathogen at pH 4.8 and 7. The descriptive method was used by descriptive method to isolate Alternaria porri and Trichoderma viride fungi and then purified, and the experimental method tested Trichoderma viride fungal antagonists against Alternaria porri with two PDA media treatments pH 4.8 that observed for 3 days and pH 7 observed for 4 days. The results of the percentage of inhibitory power on the day 1,2,3 were 9%, 34.2% and 35% (pH 4.8), and the results of the percentage of inhibition power of the day 1,2,3 and 4 were 1.9%, 29.9%, 35% and 39.4% (pH 7). The inhibition mechanism of Trichoderma viride in inhibiting Alternaria porri fungi through the stages of antibiosis, parasitism and lysis. Keywords: Trichoderma viride, Alternaria porri, shallot plants, pH 4,8 and pH 7. ABSTRAK Jamur Trichoderma viride merupakan mikroorganisme yang umum dijumpai dalam tanah yang lembab dan dapat diisolasi dari daerah perakaran tanaman bawang merah (Allium ascalonicum L.) Penelitian bertujuan untuk mengetahui mekanisme dan perbedaan persentase daya hambat oleh jamur Trichoderma viride dalam menghambat pertumbuhan patogen Alternaria porri pada pH 4,8 dan 7. Metode yamg digunakan metode deskriptif dengan mengisolasi jamur Alternaria porri dan Trichoderma viride lalu dimurnikan, dan metode eksperimen melakukan uji antagonis jamur Trichoderma viride terhadap Alternaria porri dengan dua perlakuan media PDA pH 4,8 yamg diaamati selama 3 hari dan pH 7 yang diamati selama 4 hari. Hasil persentase daya hambat pada hari ke 1,2,3 yaitu 9%, 34,2% dan 35%  (pH 4,8), dan  hasil persentase daya hambat hari ke 1,2,3 dan 4 yaitu 1,9%, 29,9%, 35% dan 39,4% (pH 7). Hal ini diketahui bahwa hasil terakhir persentase daya hambat 35% (pH 4,8) dan 39,4% (pH 7). Mekanisme Penghambatan Jamur Trichoderma viride dalam menghambat jamur Alternaria porri melalui tahap antibiosis, parasitisme dan lisis. Kata kunci: Trichoderma viride, Alternaria porri, tanaman bawang merah, pH 4,8 dan pH 7.  


2019 ◽  
Vol 13 (1) ◽  
pp. 11-20
Author(s):  
Intan Fuji Arriani

ABSTRACT Soybean plants is a strategic commodity in Indonesia, because soybean is an important crop food after rice and maize. One of the important diseases that attack soybean plants is damping off caused by pathogenic fungi S. rolfsii. One effort to suppress attack from pathogenic fungi it S. rolfsii attack is by using biological agents. Trial of antagonistic bacteria with fungi S. rolfsii  stepin vitro is test the artificial media (media NA). The result of the selection of the lumpur Sidoarjo bacterial isolates obtained 15 and 5 bacteria have antagonistic properties against pathogenic fungi S. rolfsii is  isolates LUSI 93, LUSI 43, LUSI 16, LUSI 6, and LUSI 54. The identification and characterization of antagonistic bacteria lumpur Sidoarjo is LUSI 93 belongs to the genus Vibrio sp. And for LUSI 54, 16 LUSI, LUSI 43, and LUSI 6 has been identified by previous research in a row belongs to the genus Corynebacterium sp, Vibrio sp, Erwinia sp and Corynebacterium sp.


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