Root colonization and growth promotion of soybean, wheat and Chinese cabbage by Bacillus cereus YL6

Sixteen soil samples were collected from wheat, barley and yellow corn rhizosphere in Abu-Ghraib, Aqraqof, Latifieh,Tarmiah, Jadriya and of Agriculture in Baghdad university/ Baghdad city. The results found nine phosphate solubilizing bacteria (PSB) isolates (Y1, Y2, Y3, Y4, Y5, Y6, Y7, Y8, Y9), formed clear zones on National Botanical Research Institute's (NBRIP) agar. The solubility index (SI) of PSB isolates ranged from 2.00 to 3.66. Y4 have the highest SI (3.66) followed by Y3 and Y6 (3.33). Phosphate solubilization abilities varying from (20.10-39.00 Î¼g.ml-1), Y4 was the highest (39.00 Î¼g.ml-1) followed by Y3 (37.00Î¼g.ml-1). The results of hydrolytic enzymes production showed that almost all nine isolates are able to produce protease and pectinase, while Y1 and Y2 showed negative results in cellulase production. Maximum ability for hydrogen cyanide (HCN) and indole acetic acid (IAA) production were showed byY3 and Y4 isolates. The isolate Y4 was found to be the most efficient isolate, so it was selected identified as Bacillus cereus using biochemical tests confirmed by VITEC 2 compact system. The results of High performance liquid chromatography (HPLC) revealed that Bacillus cereus produce oxalic acid (2.996), citric acid (9.117) and malic acid (3.734). Bacillus cereus (Y4) enhanced the growth of mung bean plants. A significant increase in branches number (12.33), plant length (83.0cm), fresh weight (27.25 g) and dry weight (1.427g) were obtained compared with control treatments. The main objective of this study is to isolate PSB and evaluate their roles in plant growth promotion. The results showed the high phosphate solubilization efficiency of PSB isolates and the identified isolates was found to be good enough for plant growth promoting.

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Efficacy of Plant Growth-Promoting Bacteria Bacillus cereus YN917 for Biocontrol of Rice Blast

Frontiers in Microbiology ◽

10.3389/fmicb.2021.684888 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hu Zhou ◽

Zuo-hua Ren ◽

Xue Zu ◽

Xi-yue Yu ◽

Hua-jun Zhu ◽

...

Keyword(s):

Disease Prevention ◽

Plant Growth ◽

Bacillus Cereus ◽

Rice Blast ◽

Growth Promotion ◽

Gene Clusters ◽

Plant Growth Promoting Bacteria ◽

Detached Leaf ◽

Plant Growth Promoting ◽

Growth Promoting

Bacillus cereus YN917, obtained from a rice leaf with remarkable antifungal activity against Magnaporthe oryzae, was reported in our previous study. The present study deciphered the possible biocontrol properties. YN917 strain exhibits multiple plant growth-promoting and disease prevention traits, including production of indole-3-acetic acid (IAA), ACC deaminase, siderophores, protease, amylase, cellulase, and β-1,3-glucanase, and harboring mineral phosphate decomposition activity. The effects of the strain YN917 on growth promotion and disease prevention were further evaluated under detached leaf and greenhouse conditions. The results revealed that B. cereus YN917 can promote seed germination and seedling plant growth. The growth status of rice plants was measured from the aspects of rice plumule, radicle lengths, plant height, stem width, root lengths, fresh weights, dry weights, and root activity when YN917 was used as inoculants. YN917 significantly reduced rice blast severity under detached leaf and greenhouse conditions. Genome analysis revealed the presence of gene clusters for biosynthesis of plant promotion and antifungal compounds, such as IAA, tryptophan, siderophores, and phenazine. In summary, YN917 can not only be used as biocontrol agents to minimize the use of chemical substances in rice blast control, but also can be developed as bio-fertilizers to promote the rice plant growth.

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Potencial de Bactérias para Biocontrole do Mofo Branco e Produção de Compostos Relacionados ao Sistema de Defesa em Plantas de Soja

Ensaios e Ciência C Biológicas Agrárias e da Saúde ◽

10.17921/1415-6938.2020v24n4p329-336 ◽

2020 ◽

Vol 24 (4) ◽

pp. 329-336

Author(s):

Denise Pauletto Spanhol ◽

José Rogerio De Oliveira ◽

Bianca Obes Corrêa ◽

Ismail Teodoro de Souza Junior ◽

Marcelo Vedovatto ◽

...

Keyword(s):

Glycine Max ◽

Bacillus Cereus ◽

Sclerotinia Sclerotiorum ◽

Growth Promotion ◽

Secondary Compounds ◽

White Mold ◽

Phytochemical Analysis ◽

Soybean Cultivars ◽

Detached Leaves

O presente estudo teve como objetivo avaliar o potencial de bactérias, na promoção de crescimento, produção de compostos de defesa e no biocontrole do mofo branco em folhas destacadas de duas cultivares de soja. Os ensaios foram realizados com as bactérias antagonistas FIT09 (Bacillus cereus) e FIT62 (B. thuringensis), do fungo Sclerotinia sclerotiorum e com as cultivares de soja M6210 IPRO e Brasmax Garra IPRO. Nos ensaios in vivo foram avaliados a capacidade das bactérias na promoção do crescimento de plantas de soja e na constituição dos compostos secundários produzidos pelas plantas oriundas de sementes microbiolizadas com suspensões bacterianas. Além disso, os ensaios de biocontrole do mofo branco, foram realizados com folhas destacadas em estádio V3, as quais foram pulverizadas com as suspensões das bactérias FIT09 e FIT62. As bactérias FIT09 e FIT62 apresentaram compatibilidade com B. japonicum e no ensaio de biocontrole com folhas destacadas, verificou-se que a FIT 09 reduziu o diâmetro das lesões necróticas causadas por S. sclerotiorum em ambas cultivares de soja avaliadas em teste de folhas destacadas. No ensaio de promoção de crescimento, as bactérias aumentaram o poder germinativo na cultivar M6210 IPRO. Para a avaliação da análise fitoquímica, as bactérias auxiliaram positivamente na produção dos compostos relacionados ao sistema de defesa. Palavras-chave: Metabólitos Secundários. Fitoquímica. Sclerotinia sclerotiorum. Bacillus, Glycine max Abstract The present study aimed to evaluate the potential of bacteria, in the promotion of growth, production of compounds of defens, and in the biocontrol of white mold in detached leaves of two soybean cultivars. The tests were performed with the antagonist bacteria FIT09 (Bacillus cereus) and FIT62 (B. thuringensis), with the fungus Sclerotinia sclerotiorum and with the soybean cultivars M6210 IPRO and Brasmax Garra IPRO. In vivo tests evaluated the capacity of bacteria to promote the growth of soybean plants and the constitution of secondary compounds produced by plants from microbiolized seeds with bacterial suspensions. In addition, white mold biocontrol bioassays were carried out with detached leaves in stage V3 and they were sprayed with suspensions of the bacteria FIT09 and FIT62.The bacteria FIT09 and FIT62 were compatible with B. japonicum and in the biocontrol assay with detached leaves, it was found that FIT09 promoted superior control of 70% against the disease in both cultivars, however the disease did not manifest in the assay in plants. In the growth promotion test, the bacteria increased the germinative power in cultivar M6210 IPRO, for the assessment of fresh and dry mass there were no differences and for phytochemical analysis, the bacteria positively helped in the production of compounds related to the defense system. Keywords: Secondary Metabolites. Phytochemistry, Sclerotinia sclerotiorum. Bacillus, Glycine max

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Metabolome adjustments in ectomycorrhizal Populus × canescens associated with strong promotion of plant growth by Paxillus involutus despite a very low root colonization rate

Tree Physiology ◽

10.1093/treephys/tpaa100 ◽

2020 ◽

Vol 40 (12) ◽

pp. 1726-1743

Author(s):

Agnieszka Szuba ◽

Łukasz Marczak ◽

Izabela Ratajczak

Keyword(s):

Plant Growth ◽

Root Colonization ◽

Growth Promotion ◽

P Uptake ◽

Soluble Carbohydrates ◽

Paxillus Involutus ◽

Root Tips ◽

Poplar Trees ◽

Related Proteins ◽

Poplar Growth

Abstract It is believed that resource exchange, which is responsible for intensified growth of ectomycorrhizal plants, occurs in the fungus–plant interface. However, increasing evidence indicates that such intensified plant growth, especially root growth promotion, may be independent of root colonization. Nevertheless, the molecular adjustments in low-colonized plants remain poorly understood. Here, we analysed the metabolome of Populus × canescens microcuttings characterized by significantly increased growth triggered by inoculation with Paxillus involutus, which successfully colonized only 2.1 ± 0.3% of root tips. High-throughput metabolomic analyses of leaves, stems and roots of Populus × canescens microcuttings supplemented with leaf proteome data were performed to determine ectomycorrhiza-triggered changes in N-, P- and C-compounds. The molecular adjustments were relatively low in low-colonized (M) plants. Nevertheless, the levels of foliar phenolic compounds were significantly increased in M plants. Increases of total soluble carbohydrates, starch as well as P concentrations were also observed in M leaves along with the increased abundance of the majority of glycerophosphocholines detected in M roots. However, compared with the leaves of the non-inoculated controls, M leaves presented lower concentrations of both N and most photosynthesis-related proteins and all individual mono- and disaccharides. In M stems, only a few compounds with different abundances were detected, including a decrease in carbohydrates, which was also detected in M roots. Thus, these results suggest that the growth improvement of low-colonized poplar trees is independent of an increased photosynthesis rate, massively increased resource (C:N) exchange and delivery of most nutrients to leaves. The mechanism responsible for poplar growth promotion remains unknown but may be related to increased P uptake, subtle leaf pigment changes, the abundance of certain photosynthetic proteins, slight increases in stem and root amino acid levels and the increase in flavonoids (increasing the antioxidant capacity in poplar), all of which improve the fitness of low-colonized poplars.

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