scholarly journals Nematicidal potential of Streptomyces antibioticus strain M7 against Meloidogyne incognita

AMB Express ◽  
2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Manish Sharma ◽  
Shivam Jasrotia ◽  
Puja Ohri ◽  
Rajesh Kumari Manhas

Abstract Meloidogyne spp. are microscopic, obligatory endoparasites with worldwide distribution which cause severe damage to agricultural crops. The present study revealed the nematicidal activity of Streptomyces antibioticus strain M7 against Meloidogyne incognita. The culture supernatant of the isolate caused 100% J2 mortality after 24 h and inhibited egg hatching (only 3%). In addition, the nematicidal activity of actinomycins V, X2 and D purified from strain M7 was also checked. In vitro studies displayed 97.0–99.0% juvenile mortality and 28.0–44.0% egg hatching after 168 h at 240 µg/ml of actinomycin, with LD50 (lethal dose) values of 28–120 µg/ml. In vivo study further validated the nematicidal activity of strain M7, where nematode infested tomato plants treated with culture supernatant/cells/solvent extract showed reduction in root galls and egg masses per plant by 50.0–62.06% and 53.48–76.74%, respectively, and significantly enhanced the shoot length (54.67–76.39%), root length (36.45–64.88%), shoot fresh weight (111–171.77%), root fresh weight (120–163.33%), shoot dry weight (54.45–145.45%), and root dry weight (100–133.3%) over the nematode infested plants treated with water. Furthermore, tomato plants treated with cells/culture supernatant/extract of strain M7 without nematode infestation also showed significant increase in various plant growth parameters. Thus, the outcome of the study revealed the potential of S. antibioticus strain M7 and actinomycins produced from it to be developed as safe nematicidal agents to control the root knot nematodes, and to increase the crop yield.

2021 ◽  
Vol 9 (11) ◽  
pp. 2268
Author(s):  
Xiaoyu Mei ◽  
Xin Wang ◽  
Guohong Li

Plant parasitic nematodes, especially parasitic root-knot nematodes, are one of the most destructive plant pathogens worldwide. The control of plant root-knot nematodes is extremely challenging. Duddingtonia flagrans is a type of nematode-trapping fungi (NTF), which produces three-dimensional adhesive networks to trap nematodes. In this study, the pathogenicity and volatile organic compounds (VOCs) of the NTF D. flagrans against the plant root-knot nematode, Meloidogyne incognita, were investigated. The predatory process of D. flagrans trapping M. incognita was observed using scanning electron microscopy. Gas chromatography-mass spectrometry analysis of the VOCs from D. flagrans led to the identification of 52 metabolites, of which 11 main compounds were tested individually for their activity against M. incognita. Three compounds, cyclohexanamine, cyclohexanone, and cyclohexanol, were toxic to M. incognita. Furthermore, these three VOCs inhibited egg hatching of M. incognita. Cyclohexanamine showed the highest nematicidal activity, which can cause 97.93% mortality of M. incognita at 8.71 µM within 12 h. The number of hatched juveniles per egg mass after 3 days was just 8.44 when treated with 26.14 µM cyclohexanamine. This study is the first to demonstrate the nematicidal activity of VOCs produced by D. flagrans against M. incognita, which indicates that D. flagrans has the potential to biocontrol plant root-knot nematodes.


HortScience ◽  
2000 ◽  
Vol 35 (7) ◽  
pp. 1220-1222 ◽  
Author(s):  
L. Botrini ◽  
A. Graifenberg ◽  
M. Lipucci di Paola

The tomato cultivars Edkawi and UC 82B (Lycopersicon esculentum Mill.) were grown hydroponically in a solution [electrical conductivity (EC) 2.4 dS·m-1] containing 150 mm Na (EC 11.4 dS·m-1), 37 mm of K (EC 14.1 dS·m-1), or 75 mm of K (EC 19.7 dS·m-1). The leaf Na content of `Edkawi' and `UC 82B' reached values of 1717 and 2022 mmol·kg-1 dry weight at EC 19.7 dS·m-1, respectively. The high levels of K in the hydroponic solution reduced the Na concentration in the roots, petioles, and stems, but not in the leaves. Potassium concentrations in the petioles of `Edkawi' and `UC 82 B' reached values of 2655 and 2966 mmol·kg-1 dry weight, respectively. At these elevated ECs, the Ca concentrations in the leaves of `Edkawi' and `UC 82B' were 30% and 40% lower than in the control, respectively. The elevated rates of K improved the fruit: flower ratio of `UC 82B', but the high salinity of the solution reduced yields significantly. Plant fresh weight and root dry weight of `UC 82B' were most affected by high EC levels. The elevated levels of K used in this study did not increase yield, but K ions can adjust to Na uptake.


1969 ◽  
Vol 77 (3-4) ◽  
pp. 229-236
Author(s):  
Julio Lara-Mártez ◽  
Nelia Acosta ◽  
Nydia Vicente

A soil amendment of shrimp shell at dosages of 2 and 4% (v/v) applied 25, 30 and 35 days before planting reduced damage to tomatoes caused by Meloidogyne incognita, decreasing root galling and increasing height and dry weight of plants. The 4% dosage applied 30 or 35 days before planting increased shoot dry weight of tomato plants grown on nematode infested soil in the greenhouse.


2021 ◽  
Vol 108 (Special) ◽  
Author(s):  
Ganeshan k ◽  
◽  
Vetrivelkalai p ◽  
Bhagawati B ◽  
Nibha G ◽  
...  

A field survey was conducted in 12 districts of Assam viz., Jorhat, Golaghat, Nagaon, Marigaon, Goalpara, Dibrugarh, Tinsukia, Lakhimpur, Dhemaji, Sivsagar, Kamrup and Barpeta. A total of 92 root samples were collected and 37 bacterial isolates were isolated from commercial banana cultivars. The culture filtrates extracted from 37 endophytic bacterial isolates, were screened against southern root-knot nematode, Meloidogyne incognita in vitro and under pot culture studies. The five bacterial isolates viz., EB4, EB8, BC1, BC11 and BC12 showed 100% inhibition of egg hatching and juvenile mortality of M. incognita with an exposure period of 48 and 72h. On seed bacterization, with these five promising isolates, two isolates viz.EB4, BC1 significantly enhanced germination percentage (33.33, 25.31%) and vigour index (75.5, 64.39%) of paddy, receptively. The potential bacterial isolates viz., BC1 and EB4 were identified as Lysinibacillus sp. and Pseudomonas sp., respectively , based on the morphological phenotypic and biochemical characterization. The pot culture experiment revealed that the bacterial endophytes viz., Lysinibacillus sp. (BC1) Pseudomonas sp. (EB4) significantly reduced the soil (61.64, 56.71%) and root nematode population (77.29, 68.87%), number of adult females (73.97, 69.89%), egg masses (85.63, 80.11%) and root-knot index (1.33, 1.67) of M. incognita compared to untreated control. The bacterial endophytes viz., Pseudomonas sp. (EB4), Lysinibacillus sp. (BC1) were also significantly increased the growth parameters viz., shoot length (43.33, 39.18%), and root length (78.24, 59.26%) and pesudostem girth (58.38, 52.13%).


2017 ◽  
Vol 12 (5) ◽  
pp. 1934578X1701200
Author(s):  
Yamile Massuh ◽  
Angel Cruz-Estrada ◽  
Azucena González-Coloma ◽  
Marta S. Ojeda ◽  
Julio A. Zygadlo ◽  
...  

Essential oils composition of three Tagetes minuta varieties and a wild population (WP) from Argentina and their in vitro and in vivo nematicidal activity against root-knot nematode, Meloidogyne javanica, are described. All T. minuta EOs tested were very active against nematode juveniles (J2), but the strongest nematicidal effects were exhibited by the TmV3 variety oil, characterized by a high content of ( E)-ocimenone. High nematode egg hatching suppression (> 90%) was induced by TmV3 EO after five days of incubation. In vivo tests on tomato seedlings showed a significant reduction of infection rate of M. javanica J2 treated with TmV3 and WP oils at sub lethal dose. Therefore, EOs from chemically stable new varieties of T. minuta could be environmentally friendly nematicidal agents.


2016 ◽  
Vol 6 (1) ◽  
pp. 23-33
Author(s):  
L. D. Amarasinghe ◽  
N. W. Premachandra

This study was conducted to determine the nematicidal effect of aqueous extractions of dry plant materials, Tithonia diversifolia, Gliricidia sepium and Tagetes erecta on juveniles of Meloidogyne incognita (Kofoid and White) and to determine the effect of dry leaves of wild sunflower, dry leaves of Gliri-cidia, and dry plant parts of marigold as cover crops on the growth of potted tomato, Lycopersicon esculentum (Mill.) infested with M. incognita. Nemati-cidal effect of aqueous extracts of T. diversifolia, G. sepium and T. erecta (20 g/ 100 mL w/v) were evaluated at 0.05 g/mL, 0.1 g/mL and 0.2 g/mL concentrations in the laboratory bioassay. Results revealed that 0.1 g/ mL and 0.2 g/ mL concentration of T. erecta and 0.2 g/mL concentration of T. diversifolia were very effective in juvenile mortality by over 50% within 48 hours com-pared to other treatments. T. erecta plant parts were the most effective causing above 70% juvenile mortality in 48 hours. M. incognita infested potted tomato plants supplement with dry plant parts of Marigold (2% w/w) showed; significantly higher number of green leaves (P=0.000, F=10.95); significantly lower number of yellow leaves (P=0.001, F=6.78); significantly high-er plant height (P=0.000, F=8.90), stem diameter (P=0.000, F=11.83), root length (P=0.000, F=14.71) and root weight (P=0.000, F=15.08); significantly lower number of root galls (P=0.000, F=116.74), gall index (P=0.000, F=95.80) and significantly lower population of M. incognita in soil (P=0.000, F=24.78) compared to other treatments. This study concludes that addition of botani-cals as cover crops enhanced plant growth and significantly reduced root-knot infestation in tomato plants.


2010 ◽  
Vol 100 (2) ◽  
pp. 199-203 ◽  
Author(s):  
Sergio Echeverrigaray ◽  
Jucimar Zacaria ◽  
Ricardo Beltrão

Nematicidal activity of 22 monoterpenoids were evaluated in vitro and in pot experiments. Twenty of the twenty-two monoterpenoids significantly reduced hatching, and 11 reduced J2 mobility of the root-knot nematode Meloidogyne incognita at a concentration of 250 mg/liter. In general, compounds with hydroxyl and carbonyl groups exhibited higher nematicidal activity than other terpenoids. Borneol, carveol, citral, geraniol, and α-terpineol showed the highest nematicidal activity among the in vitro tested monoterpenoids. These compounds exhibited a dose dependent effect, and drastically reduced eggs hatching and J2 viability at low concentrations. These monoterpenoids, at 100 and 250 mg/kg concentration, diminished root galling of tomato plants in pot experiments. The results suggest that the selected monoterpenoids, and essential oils with high concentration of these compounds, are potential nematicides against Meloidogyne.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Hosny Kesba ◽  
Abdullah Abdel-Rahman ◽  
Samy Sayed ◽  
Al-Sayed Al-Sayed

Abstract Background The root-knot nematode, Meloidogyne incognita, causes a high damage and yield decrease for many economic plants. The need for non-systemic effective new approaches and environmentally friendly methods for controlling the nematodes has directed research to some new and safe agrochemicals found in medicinal plants as new viable management options. Results In laboratory experiments, solidago and periwinkle aqueous and ethanolic extracts achieved high J2 mortality (%) concerning different dilutions; however, aqueous extracts were more effective for mortality than ethanolic extracts. Also, there was a direct relationship between the nematicidal activity of these extracts with both concentration and time of application. Inhibition of egg hatching by Periwinkle extracts was higher than that of solidago. Moreover, the nematicidal activity of tested extracts against J2 decreased significantly with prolonged storage time at + 5 °C, while did not with stored frozen at – 5 °C for 12 months. Periwinkle and solidago extracts killed the non-target organisms, i.e., rotifers and free-living nematodes. Seventy-five and 90% of total phytochemicals recovered from periwinkle and solidago, respectively were nematostatic or nematicidal to nematode viability, egg hatch in vitro, and development and reproduction in vivo despite the method of application (foliar and soil drench). The antagonistic effects of solidago were more pronounced in soil drench than periwinkle concerning their concentrations and methods of application. Conclusion Solidago and periwinkle plant extracts showed important sources of effective control phytochemicals against M. incognita.


2013 ◽  
Vol 40 (1-2) ◽  
pp. 5-14 ◽  
Author(s):  
Piotr M. Piszczek ◽  
Marek Jerzy

Inhibition of the growth of young tomato plants took place under the influence of vibrational stress. The response of the plants was stronger in winter than in summer. The results of the mechanical stress treatment depended on the dosage: small doses of stress given repeatedly slowed down the growth of the transplant much more effectively than larger single doses given every day or every several days. The fresh weight of the shoots decreased under the influence of the stress, as did the dry weight, but to a smaller degree, thus the percentage of dry weight increased. The chlorophyll content in the leaves of plants treated with mechanical stress also increased.


Sign in / Sign up

Export Citation Format

Share Document