scholarly journals Effects of Endophytic Bacillus Subtilis and Salicylic Acid on Postharvest Diseases (Phytophthora infestans, Fusarium oxysporum) Development in Stored Potato Tubers

Plants ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 76 ◽  
Author(s):  
Oksana Lastochkina ◽  
Andrey Baymiev ◽  
Aysylu Shayahmetova ◽  
Darya Garshina ◽  
Igor Koryakov ◽  
...  

Postharvest diseases of potato lead to significant food and economic losses worldwide. The exogenous application of eco-friendly methods plays an important role in the control of postharvest decay. In this work the effects of endophytic bacteria B. subtilis (10-4, 26D) were studied in the context of two application parameters: concentration, with a range between 103–108 CFU/mL tested, and synergistic effects of the signal molecule salicylic acid (SA) (0.05 mM) on potato tubers’ resistance to Phytophthora infestans and Fusarium oxysporum during storage. The experiments were carried out on hydroponically grown potato (Solanum tuberosum L.) mini-tubers. This study demonstrates the suppressive effect of B. subtilis (10-4, 26D) on diseases of potato during storage and reveals that this effect happens in a dose-dependent manner, both individually and in combination with SA. The most effective concentrations of B. subtilis for suppression of both Ph. infestans and F. oxysporum are 108 CFU/mL (10-4 and 26D), 107 CFU/mL (10-4 + SA) and 106 CFU/mL (26D + SA). The ability of B. subtilis (10-4, 26D) to effectively penetrate and colonize the internal tubers’ tissues when applied immediately prior to storage, and the ability of SA to accelerate these processes, have been proven. B. subtilis (10-4, 26D), individually and in compositions with SA, increased ascorbic acid content and decreased pathogen-induced proline accumulation and lipid peroxidation in tubers. This indicates a protective effect conferred to cells against reactive oxygen and an extension of aging processes, manifested by a prolonged shelf life and extended preservation of fresh appearance.

2020 ◽  
Vol 86 (9) ◽  
Author(s):  
Yunlong Li ◽  
Shenyan Dai ◽  
Baoying Wang ◽  
Yuting Jiang ◽  
Yanyu Ma ◽  
...  

ABSTRACT Autotoxic ginsenosides have been implicated as one of the major causes for replant failure of Sanqi ginseng (Panax notoginseng); however, the impact of autotoxic ginsenosides on the fungal microbiome, especially on soilborne fungal pathogens, remains poorly understood. In this study, we aimed to investigate the influence of the ginsenoside monomers Rg1, Rb1, and Rh1, and that of their mixture (Mix), on the composition and diversity of the soil fungal community, as well as on the abundance and growth of the soilborne pathogen Fusarium oxysporum in pure culture. The addition of autotoxic ginsenosides altered the composition of the total fungal microbiome, as well as the taxa within the shared and unique treatment-based components, but did not alter alpha diversity (α-diversity). In particular, autotoxic ginsenosides enriched potentially pathogenic taxa, such as Alternaria, Cylindrocarpon, Gibberella, Phoma, and Fusarium, and decreased the abundances of beneficial taxa such as Acremonium, Mucor, and Ochroconis. Relative abundances of pathogenic taxa were significantly and negatively correlated with those of beneficial taxa. Among the pathogenic fungi, the genus Fusarium was most responsive to ginsenoside addition, with the abundance of Fusarium oxysporum consistently enhanced in the ginsenoside-treated soils. Validation tests confirmed that autotoxic ginsenosides promoted mycelial growth and conidial germination of the root rot pathogen F. oxysporum. In addition, the autotoxic ginsenoside mixture exhibited synergistic effects on pathogen proliferation. Collectively, these results highlight that autotoxic ginsenosides are capable of disrupting the equilibrium of fungal microbiomes through the stimulation of potential soilborne pathogens, which presents a significant hurdle in remediating replant failure of Sanqi ginseng. IMPORTANCE Sanqi ginseng [Panax notoginseng (Burk.) F. H. Chen] is geoauthentically produced in a restricted area of southwest China, and successful replanting requires a rotation cycle of more than 15 to 30 years. The increasing demand for Sanqi ginseng and diminishing arable land resources drive farmers to employ consecutive monoculture systems. Replant failure has severely threatened the sustainable production of Sanqi ginseng and causes great economic losses annually. Worse still, the acreage and severity of replant failure are increased yearly, which may destroy the Sanqi ginseng industry in the near future. The significance of this work is to decipher the mechanism of how autotoxic ginsenosides promote the accumulation of soilborne pathogens and disrupt the equilibrium of soil fungal microbiomes. This result may help us to develop effective approaches to successfully conquer the replant failure of Sanqi ginseng.


2005 ◽  
Vol 18 (4) ◽  
pp. 343-353 ◽  
Author(s):  
C. L. Pemberton ◽  
N. A. Whitehead ◽  
M. Sebaihia ◽  
K. S. Bell ◽  
L. J. Hyman ◽  
...  

Seven new genes controlled by the quorum-sensing signal molecule N-(3-oxohexanoyl)-L-homoserine lactone (OHHL) have been identified in Erwinia carotovora subsp. carotovora. Using TnphoA as a mutagen, we enriched for mutants defective in proteins that could play a role in the interaction between E. carotovora subsp. carotovora and its plant hosts, and identified NipEcc and its counterpart in E. carotovora subsp. atroseptica. These are members of a growing family of proteins related to Nep1 from Fusarium oxysporum which can induce necrotic responses in a variety of dicotyledonous plants. NipEcc produced necrosis in tobacco, NipEca affected potato stem rot, and both affected virulence in potato tubers. In E. carotovora subsp. carotovora, nip was shown to be subject to weak repression by the LuxR family regulator, EccR, and may be regulated by the negative global regulator RsmA.


1999 ◽  
Vol 89 (9) ◽  
pp. 722-727 ◽  
Author(s):  
Matthew E. Spletzer ◽  
Alexander J. Enyedi

Alternaria solani is the causal agent of early blight disease in tomato and is responsible for significant economic losses sustained by tomato producers each year. Because salicylic acid (SA) is an important signal molecule that plays a critical role in plant defense against pathogen invasion, we investigated if the exogenous application of SA would activate systemic acquired resistance (SAR) against A. solani in tomato leaves. The addition of 200 μM SA to the root system significantly increased the endogenous SA content of leaves. Free SA levels increased 65-fold over basal levels to 5.85 μg g-1 fresh weight (FW) after 48 h. This level of SA had no visible phytotoxic effects. Total SA content (free SA + SA-glucose conjugate) increased to 108 μg g-1 FW after 48 h. Concomitant with elevated SA levels, expression of the tomato pathogenesis-related (PR)-1B gene was strongly induced within 24 h of the addition of 200 μM SA. PR-1B expression was still evident after 48 h; however, PR-1B induction was not observed in plants not receiving SA treatment. Challenge inoculation of SA-treated tomato plants using conidia of A. solani resulted in 83% fewer lesions per leaf and a 77% reduction in blighted leaf area as compared with control plants not receiving SA. Our data indicate that root feeding 200 μM SA to tomato plants can (i) significantly elevate foliar SA levels, (ii) induce PR-1B gene expression, and (iii) activate SAR that is effective against A. solani.


2007 ◽  
Vol 20 (11) ◽  
pp. 1346-1352 ◽  
Author(s):  
Vincentius A. Halim ◽  
Lennart Eschen-Lippold ◽  
Simone Altmann ◽  
Mandy Birschwilks ◽  
Dierk Scheel ◽  
...  

The importance of the signaling compound salicylic acid for basal defense of potato (Solanum tuberosum L. cv. Désirée) against Phytophthora infestans, the causal agent of late blight disease, was assessed using transgenic NahG potato plants which are unable to accumulate salicylic acid. Although the size of lesions caused by P. infestans was not significantly different in wild-type and transgenic NahG plants, real-time polymerase chain reaction analyses revealed a drastic enhancement of pathogen growth in potato plants depleted of salicylic acid. Increased susceptibility of NahG plants correlated with compromised callose formation and reduced early defense gene expression. NahG plants pretreated with the salicylic acid analog 2,6-dichloro-isonicotinic acid allowed pathogen growth to a similar extent as did wild-type plants, indicating that salicylic acid is an important compound required for basal defense of potato against P. infestans.


2019 ◽  
Vol 9 (2) ◽  
pp. 91
Author(s):  
Ghea Dotulong ◽  
Stella Umboh ◽  
Johanis Pelealu

Uji Toksisitas Beberapa Fungisida Nabati terhadap Penyakit Layu Fusarium (Fusarium oxysporum) pada Tanaman Kentang (Solanum tuberosum L.) secara In Vitro (Toxicity Test of several Biofungicides in controlling Fusarium wilt (Fusarium oxysporum) in Potato Plants (Solanum tuberosum L.) by In Vitro) Ghea Dotulong1*), Stella Umboh1), Johanis Pelealu1), 1) Program Studi Biologi, FMIPA Universitas Sam Ratulangi, Manado 95115*Email korespondensi: [email protected] Diterima 9 Juli 2019, diterima untuk dipublikasi 10 Agustus 2019 Abstrak Tanaman kentang (Solanum tuberosum L.) adalah salah satu tanaman hortikultura yang sering mengalami penurunan dari segi produksi dan produktivitasnya, akibat adanya serangan penyakit layu yang salah satunya disebabkan oleh Fusarium oxysporum. Tujuan penelitian ini adalah mengidentifikasi toksisitas beberapa fungisida nabati dalam mengendalikan penyakit Layu Fusarium (F. oxysporum) pada tanaman kentang (Solanum tuberosum L.) secara In Vitro. Metode Penelitian yang digunakan yaitu metode umpan beracun. Data dianalisis dengan Rancangan Acak Lengkap (RAL) dengan Analisis Varian (ANAVA) yang dilanjutkan dengan menggunakan metode BNT (Beda Nyata Terkecil). Hasil Penelitian, diperoleh nilai toksisitas fungisida nabati tertinggi yaitu pada ekstrak daun sirsak dengan nilai HR (69,44%), kategori berpengaruh, ditandai dengan diameter koloni 2,75 cm (100ppm) dan yang terendah toksisitasnya yaitu pada ekstrak daun jeruk purut dengan nilai HR (49,81%), kategori cukup berpengaruh ditandai dengan diameter koloni 3,75 cm (25ppm). Semakin tinggi konsentrasi yang diujikan maka semakin tinggi toksisitas dari fungisida nabati yang diberikan.Kata Kunci: fungisida nabati, Fusarium oxysporum, tanaman kentang, In Vitro Abstract Potato plants (Solanum tuberosum L.) is one of the horticulture plants which often decreases in terms of production and productivity, due to the attack of wilt, one of which is caused by Fusarium oxysporum. The purpose of this study was to determine the toxicity of several biofungicides in controlling Fusarium wilt (F. oxysporum) in potato plants (Solanum tuberosum L.) in Vitro. The research method used was the In Vitro method with the poison bait method. Data were analyzed by Completely Randomized Design with Variant Analysis (ANAVA), followed by the BNT method. The results showed that the highest biofungicide toxicity value was soursop leaf extract with HR values (69.44%), influential categories, characterized by colony diameter 2.75 cm (100ppm) and the lowest toxicity, namely in kaffir lime leaf extract with a value of HR (49.81%), quite influential category was characterized by colony diameter of 3.75 cm (25ppm). The higher the concentration tested, the higher the toxicity of the biofungicide given.Keywords: biofungicides, Fusarium oxysporum, Potato Plants, In Vitro.


Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3830
Author(s):  
Ahmad Almadhor ◽  
Hafiz Tayyab Rauf ◽  
Muhammad Ikram Ullah Lali ◽  
Robertas Damaševičius ◽  
Bader Alouffi ◽  
...  

Plant diseases can cause a considerable reduction in the quality and number of agricultural products. Guava, well known to be the tropics’ apple, is one significant fruit cultivated in tropical regions. It is attacked by 177 pathogens, including 167 fungal and others such as bacterial, algal, and nematodes. In addition, postharvest diseases may cause crucial production loss. Due to minor variations in various guava disease symptoms, an expert opinion is required for disease analysis. Improper diagnosis may cause economic losses to farmers’ improper use of pesticides. Automatic detection of diseases in plants once they emerge on the plants’ leaves and fruit is required to maintain high crop fields. In this paper, an artificial intelligence (AI) driven framework is presented to detect and classify the most common guava plant diseases. The proposed framework employs the ΔE color difference image segmentation to segregate the areas infected by the disease. Furthermore, color (RGB, HSV) histogram and textural (LBP) features are applied to extract rich, informative feature vectors. The combination of color and textural features are used to identify and attain similar outcomes compared to individual channels, while disease recognition is performed by employing advanced machine-learning classifiers (Fine KNN, Complex Tree, Boosted Tree, Bagged Tree, Cubic SVM). The proposed framework is evaluated on a high-resolution (18 MP) image dataset of guava leaves and fruit. The best recognition results were obtained by Bagged Tree classifier on a set of RGB, HSV, and LBP features (99% accuracy in recognizing four guava fruit diseases (Canker, Mummification, Dot, and Rust) against healthy fruit). The proposed framework may help the farmers to avoid possible production loss by taking early precautions.


2021 ◽  
Vol 11 (8) ◽  
pp. 3542
Author(s):  
Ramida Krumsri ◽  
Kaori Ozaki ◽  
Toshiaki Teruya ◽  
Hisashi Kato-Noguchi

Phytotoxic substances released from plants are considered eco-friendly alternatives for controlling weeds in agricultural production. In this study, the leaves of Afzelia xylocarpa (Kurz) Craib. were investigated for biological activity, and their active substances were determined. Extracts of A. xylocarpa leaf exhibited concentration-dependent phytotoxic activity against the seedling length of Lepidium sativum L., Medicago sativa L., Phleum pratense L., and Echinochloa crus-galli (L.) P. Beauv. Bioassay-guided fractionation of the A. xylocarpa leaf extracts led to isolating and identifying two compounds: vanillic acid and trans-ferulic acid. Both compounds were applied to four model plants using different concentrations. The results showed both compounds significantly inhibited the model plants’ seedling length in a species-dependent manner (p < 0.05). The phytotoxic effects of trans-ferulic acid (IC50 = 0.42 to 2.43 mM) on the model plants were much greater than that of vanillic acid (IC50 = 0.73 to 3.17 mM) and P. pratense was the most sensitive to both compounds. In addition, the application of an equimolar (0.3 mM) mixture of vanillic acid and trans-ferulic acid showed the synergistic effects of the phytotoxic activity against the root length of P. pratense and L. sativum. These results suggest that the leaves of A. xylocarpa and its phytotoxic compounds could be used as a natural source of herbicides.


BioTech ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 8
Author(s):  
Olalekan Olanrewaju Bakare ◽  
Arun Gokul ◽  
Marshall Keyster

Fusarium oxysporum remains one of the leading causes of economic losses and poor crop yields; its detection is strained due to its presentation in various morphological and physiological forms. This research work sought to identify novel biomarkers for the detection of Fusarium oxysporum using in silico approaches. Experimentally validated anti-Fusarium oxysporum antimicrobial peptides (AMPs) were used to construct a profile against Fusarium oxysporum. The performance and physicochemical parameters of these peptides were predicted. The gene for the Fusarium oxysporum receptor protein PR-1-like Protein, Fpr1, was identified and translated. The resulting protein model from the translation was then validated. The anti-Fusarium oxysporum AMPs and Fusarium oxysporum receptor protein 3-D structures were characterized, and their docking interaction analyses were carried out. The HMMER in silico tool identified novel anti-Fusarium oxysporum antimicrobial peptides with good performance in terms of accuracy, sensitivity, and specificity. These AMPs also displayed good physicochemical properties and bound with greater affinity to Fusarium oxysporum protein receptor PR-1-like Protein. The tendency of these AMPs to precisely detect Fusarium oxysporum PR-1-like Protein, Fpr1, would justify their use for the identification of the fungus. This study would enhance and facilitate the identification of Fusarium oxysporum to reduce problems associated with poor crop yield, economic losses, and decreased nutritional values of plants to keep up with the growing population.


Sign in / Sign up

Export Citation Format

Share Document