Role of cyanide production by Pseudomonas fluorescens CHA0 in the suppression of root-knot nematode, Meloidogyne javanica in tomato

Penyakit puru akar pada tanaman kenaf (Hibiscus cannabinus L.) yang disebabkan oleh nematoda Meloidogyne spp. mengakibatkan penurunan kualitas dan kuantitas serat. Kolonisasi rizobakteri dalam rizosfer berperan sebagai antagonis yang dapat dimanfaatkan dalam ketahanan tanaman terhadap patogen. Peran rizobakteri sebagai bioprotektan dapat menurunkan populasi nematoda yang akan mempengaruhi perkembangan patogen penyebab penyakit. Penelitian ini bertujuan untuk mengevaluasi rizobakteri yang potensial dalam meningkatkan ketahanan tanaman kenaf terhadap infeksi nematoda Meloidogyne spp. melalui pembentukan metabolit sekunder diantaranya kandungan total fenol dan asam salisilat. Aplikasi rizobakteri dengan cara perendaman dan tanpa perendaman baik secara tunggal maupun konsorsium. Rizobakteri yang digunakan terdiri dari 3 jenis yaitu Pseudomonas fluorescens, Bacillus subtilis, dan Azotobacter sp. Pengamatan kandungan total fenol dan asam salisilat diamati pada 15 dan 25 hari setelah inokulasi dengan menggunakan alat spektrofotometer. Peningkatan total fenol dan asam salisilat tertinggi diperoleh ketika benih kenaf direndam dengan bakteri P. fluorescens berturut-turut sebesar 513,45% dan 235,99%. Terdapat peningkatan bobot kering tanaman kenaf dengan aplikasi rizobakteri dibandingkan dengan kontrol. Effect of Rhizobacteria in Content of Salicylic Acid and Total Phenol of Kenaf Against Nematodes Infections Root knoot disease of kenaf caused by nematodes Meloidogyne spp. is an important disease since it lowers quality and quantity of the fiber. Colonization of rhizobacteria in rhizosphere acts as an antagonist that can be utilized in plant resistance to pathogens. The role of rhizobacteria as a bioprotectan could reduce nematode population, and thus affect development of the disease. This study aimed to evaluate the potency of rhizobacteria in improving kenaf resistance against root knot nematode by inhibiting the production of total phenols and salicylic acid. Application of rhizobacteria was done by soaking or without soaking kenaf seeds either singly or in consortium. There were three rhizobacteria used in this study, i.e: Pseudomonas fluorescens, Bacillus subtilis, and Azotobacter sp. The content of total phenols and salicylic acid was observed at 15 and 25 days after inoculation using a spectrophotometer. The highest elevation level of total phenols and salicylic acid was obtained when kenaf seeds were soaked in P. fluorescens 513,45% and 235,99% respectively. There is an increase dry weight of kenaf with aplication of rhizobacteria compared with controls.

Download Full-text

Mineral composition of beetroot treated with potential elicitors and inoculated with Meloidogyne javanica

Chemical and Biological Technologies in Agriculture ◽

10.1186/s40538-020-00196-2 ◽

2020 ◽

Vol 7 (1) ◽

Author(s):

Paula Juliana Grotto Débia ◽

Beatriz Cervejeira Bolanho ◽

Claudia Regina Dias-Arieira

Keyword(s):

Population Density ◽

Mineral Composition ◽

Integrated Management ◽

Meloidogyne Javanica ◽

Nematode Population ◽

Root Knot Nematode ◽

Cu Content ◽

Manganese Zinc ◽

Nematode Population Density ◽

Elicitor Treatments

Abstract Background The root-knot nematode Meloidogyne javanica can infect beetroots, causing extensive damage to this food crop. As chemical and genetic control tactics have shown limited efficacy, new strategies are needed to improve the integrated management of this parasite. This study assessed the influence of potential defence elicitors and M. javanica infection on the mineral composition of beetroot. Plants were treated with acibenzolar-S-methyl (ASM), citrus biomass, or a mannanoligosaccharide-based product (MOS) and inoculated with 1000 eggs and second-stage juveniles of M. javanica. At 60 days after inoculation, beetroot plants were harvested and evaluated for nematode population density, vegetative growth, and mineral content. Results All potential elicitors reduced nematode population density in beetroots (p ≤ 0.10) and improved the vegetative parameters of inoculated plants (p ≤ 0.05), except shoot fresh weight. Some minerals were found to be negatively affected by treatments, particularly calcium, whose levels were consistently lower in treated plants. On the other hand, M. javanica inoculation increased magnesium, iron, manganese, zinc, and copper contents in beetroots. However, the latter mineral (Cu content) of inoculated plants was positively influenced by MOS and ASM. Conclusion Potential elicitor treatments did not improve the mineral composition of beetroot, but were effective in reducing nematode population density. Plants inoculated with M. javanica had higher mineral levels. However, gall formation decreases the commercial value of the crop and might render it unsuitable for commercialisation. M. javanica-infected beetroots may be used for nutrient extraction or sold to food processing industries.

Download Full-text

Efficacy of integrated microorganisms in controlling root-knot nematode Meloidogyne javanica infecting peanut plants under field conditions

Bulletin of the National Research Centre ◽

10.1186/s42269-020-00366-0 ◽

2020 ◽

Vol 44 (1) ◽

Author(s):

Hamida Ahmed Osman ◽

Hoda Hussein Ameen ◽

Moawad Mohamed ◽

Usama Samy Elkelany

Keyword(s):

Meloidogyne Javanica ◽

Field Conditions ◽

Root Knot Nematode

Download Full-text

A Single Recessive Gene for Resistance to the Root-Knot Nematode (Meloidogyne Javanica) in Cucumis sativus var. hardwlckii

Journal of Heredity ◽

10.1093/oxfordjournals.jhered.a023060 ◽

1997 ◽

Vol 88 (1) ◽

pp. 66-69 ◽

Cited By ~ 9

Author(s):

S. A. Walters ◽

T. C. Wehner ◽

K. R. Barker

Keyword(s):

Cucumis Sativus ◽

Recessive Gene ◽

Meloidogyne Javanica ◽

Single Recessive Gene ◽

Root Knot Nematode

Download Full-text

A case of infection on the scion of grafted tomatoes by the root-knot nematode Meloidogyne javanica

Acta agriculturae Slovenica ◽

10.2478/v10014-007-0012-z ◽

2007 ◽

Vol 89 (1) ◽

Cited By ~ 2

Author(s):

Emmanuel Tzortzakakis

Keyword(s):

Meloidogyne Javanica ◽

Root Knot Nematode

Download Full-text

The effect of organic compost of Caryocar brasiliense waste against Meloidogyne javanica in two vegetable crops

Nematology ◽

10.1163/15685411-bja10103 ◽

2021 ◽

pp. 1-8

Author(s):

Fabíola de J. Silva ◽

Regina C.F. Ribeiro ◽

Adelica A. Xavier ◽

Vanessa A. Gomes ◽

Paulo V.M. Pacheco ◽

...

Keyword(s):

Integrated Control ◽

Meloidogyne Javanica ◽

Control Measures ◽

Vegetable Crops ◽

Root Knot Nematode ◽

Second Stage ◽

Tomato Roots ◽

Crop Development ◽

Caryocar Brasiliense ◽

Organic Compost

Summary Root-knot nematodes (Meloidogyne spp.) are responsible for various significant crop losses, which require taking integrated control measures. The present study aimed to identify a possible sustainable approach to the management of Meloidogyne javanica in vegetable crops using an organic compound based on pequi (Caryocar brasiliense) fruit residues. A pot experiment was conducted using cultivars of tomato and lettuce susceptible to M. javanica, with three amendments including inorganic fertiliser, cattle manure and five doses of organic compost with pequi residues. All treatments were inoculated with second-stage juveniles of M. javanica to simulate the root-knot nematode disease in field conditions. Increasing doses of organic compost with pequi residues from 5 kg m−3 to 30 kg m−3 promoted a significant decrease in the nematode population in both cultures evaluated. Organic compost (30 kg m−3) reduced the numbers of galls and eggs of M. javanica by 41.6 and 46.5% in tomato roots, and by 80.3 and 59.2% in lettuce roots, respectively, compared with non-treated control. Organic compost also increased crop development considerably. In general, there was a 43.0% increase in plant development compared to non-treated control. Hence, organic compost of pequi residues could be an alternative to toxic chemical nematicides and recommended as eco-friendly management of M. javanica in vegetable crops.

Download Full-text