Interactive effects of Arbuscular mycorrhizal fungi and rhizobial strains on chickpea growth and nutrient content in plant

Legumes form a tripartite symbiosis with Arbuscular mycorrhizal fungi (AMF) and rhizobia. Chickpea plants were inoculated with six strains of Mesorhizobium ciceri and three AMF species, Glomus intraradices (GI), G. mosseae (GM) and G. etunicatum (GE). The plants inoculated with a number of AMF species and bacterial strains increased overall plant dry mass compared to non-inoculated plants. GE was the most efficient in increasing plant dry matter. Individual AMF species were more effective than when mixed (GI+GM+GE). Bacterial treatments had increasing effect on root colonization by GI, GM and GI+GM+GE. The results revealed that dual inoculation with AMF and rhizobium enhanced nitrogen, phosphorus, zinc, iron and copper content in plants but these increasing effects was different between fungal and bacterial treatments.Key words: Arbuscular mycorrhizal fungi, Mesorhizobium ciceri, nutrient content, root colonization, nodule, chickpea

Organic Nitrogen in Agricultural Systems

This work summarizes information about organic nitrogen (N) in the agricultural system. The organic N forms in soils have been studied by identifying and quantifying the released organic compounds when soils are acid treated at high temperature, in which the following organic N fractions are obtained: hydrolyzable total N, subdivided into hydrolyzable NH4+-N, amino sugars-N, amino acids-N, and unidentified-N and acid insoluble N, a fraction that remains associated with soil minerals after acid hydrolysis. Nitrogen mineralization and immobilization are biochemical processes in nature. This chapter summarizes how these processes occur in the agricultural system. Then, soluble organic nitrogen (SON), volatilization and denitrification processes, and biological nitrogen fixation (BNF) as a key component of the nitrogen cycle and how it makes N available to plants are also discussed. Finally, we discuss the use of organic fertilizers as N source to satisfy the worldwide demand for organic foods produced without synthetic inputs

Inoculation with Azospirillum brasiliense increases maize yield.

We evaluated the effect of A. brasiliense inoculation on maize cultivated under no tillage system

Serapan Logam Berat oleh Fungi Mikoriza Arbuskula Lokal pada Nauclea orientalis L. dan Potensial untuk Fitoremediasi Tanah Serpentine

Pengaruh fungi mikoriza arbuskula (FMA) lokal terhadap pertumbuhan dan serapan logam tanaman Nauclea orientalis L., telah diteliti. Tanaman ditumbuhkan pada kondisi rumah kaca pada media serpentine soil tanpa dan dengan FMA (Glomus sp., Acaulospora tuberculata, dan campuran) selama 2 bulan. Akar tanaman lonkida terkolonisasi FMA dengan ditemukan struktur FMA berupa hifa internal>hifa eksternal>coil> vesikula>arbuskula. Kolonisasi A. tuberculata dan Glomus sp. signifikan meningkatkan berat kering akar (P65). Nilai Transpor Faktor (TF) Mn>Ni>Cr. Glomus sp mengurangi serapan Fe dan Ni akar sebesar 13% dan 3%, secara berturutan. A. tuberculata meningkatkan serapan semua logam. Kemampuan serapan logam berbeda antara jenis FMA.Heavy Metal Uptake by Indigenous Arbuscular Mycorrhizas of Nauclea orientalis L. and the Potential for Phytoremediation of Serpentine SoilAbstractEffect of indigenous arbuscular mycorrhizal fungi (AMF) on growth and metal uptake of Nauclea orientalis L. plants, has been investigated. Plants were grown in greenhouse conditions on serpentine soil media without and with the AMF (Glomus sp., Acaulospora tuberculata, and mix) for two months. Lonkida roots was colonized by AMF because it was found structures of AMF: internal hyphae>external hypae>coil>vesicles>arbuscule. Colonization A. tuberculata and Glomus sp. significantly increased dry weight of root (P65). Transport Factor value (TF) Mn>Ni>Cr. Glomus sp reduced Fe and Ni uptake on roots by 13% and 3%, respectively. A. tuberculata increased the uptake of all metals. Metal uptake ability was difference among types of AMF

Diversity of inulinase-producing fungi associated with two Asteraceous plants, Pulicaria crispa (Forssk.) and Pluchea dioscoridis (L.) growing in an extreme arid environment

Inulinases are potentially valuable enzymes catalyze the hydrolysis of plant’s inulin into high fructose syrups as sweetening ingredients for food industry and ethanol production. The high demands for inulinase enzymes have promoted interest in microbial inulinases as the most suitable approach for biosynthesis of fructose syrups from inulin. Arid land ecosystem represents a valuable bioresource for soil microbial diversity with unique biochemical and physiological properties. In the present study, we explored the fungi diversity associated with the rhizosphere and rhizoplane of two desert medicinal plants namely Pluchea dioscoridis and Pulicaria crispa growing in the South-Eastern desert of Aswan, Egypt. A total of 180 fungal isolates were screened based on their ability to grow on potato dextrose agar medium supplemented with 1% inulin. The isolated fungal colonies were morphologically identified according to cultural characteristics and spore-bearing structure. In addition, the inulinase activity of the isolated fungi was examined spectrophotometrically. Among these, Aspergillus terreus var. terreus 233, Botrytis cinerea, Aspergillus aegyptiacus, Cochliobolus australiensis 447 and Cochliobolus australiensis exhibited high inulinase activity ranging from 5.05 to 7.26 U/ml. This study provides a promising source of microbial inulinase, which can be scaled up for industrial applications. DOI: http://dx.doi.org/10.5281/zenodo.120564

Diversidade funcional de bactérias isoladas de solos rizosférico e não rizosférico em cultura de milho

This study evaluated the hydrolytic and phosphate-solubilizing potentials of soil bacteria isolated from a red latosol (oxisol) under maize cultivation. Rhizosphere soil (SR) and non-rhizosphere soil (NR) were collected and, subsequently, distinct bacterial colonies were isolated in pure cultures. Solid culture media were employed to evaluate production of hydrolases and phosphate solubilization by the isolates. From SR and NR, 30 and 19 distinct colonial types were isolated, respectively. From 29 SR isolates, 68.9%, 65.5%, 20.7% and 24.1% displayed proteolytic, cellulolytic, amylolytic, and phosphate-solubilizing activities, respectively. From the NR isolates, 57.9% produced cellulase, 42.1% protease, 57.9% amylase and 21.0% solubilized phosphate; however, 31.6% of these isolates did not display any activity. Diverse bacteria presented combined activities, representing about 58% of the SR and NR isolates. In addition to environmental and agricultural relevance, the microbial ability to secrete enzymes related to carbon and nitrogen cycles and phosphate solubilization might be important from a biotechnological perspective.Este estudo avaliou os potenciais hidrolítico e de solubilização de fosfato de bactérias isoladas de Latossolo Vermelho cultivado com milho. A coleta de solo rizosférico (SR) e solo não rizosférico (NR) foi realizada, sendo procedido o isolamento de colônias bacterianas em culturas puras. Meios de cultura sólidos foram utilizados na avaliação da produção de hidrolases e solubilização de fosfato pelos isolados. A partir de SR e NR foram isolados 30 e 19 tipos coloniais distintos, respectivamente. De 29 isolados de SR, 68,9%, 65,5%, 20,7% e 24,1% apresentaram atividade proteolítica, celulolítica, amilolítica e solubilização de fosfato, respectivamente. Dos isolados de NR, 57,9% produziram celulase, 42,1% protease, 57,9% amilase e 21,0% solubilizaram fosfato; contudo, 31,6% destes isolados não demonstraram qualquer atividade. Diversas bactérias apresentaram atividades combinadas, representado aproximadamente 58% dos isolados de SR e NR. Além da relevância ambiental e agrícola, a habilidade microbiana em secretar enzimas relacionadas ao ciclo do carbono e nitrogênio e a solubilização de fosfato podem ser importantes na perspectiva biotecnológica

Effect of Burkholderia tropica and Herbaspirillum frisingense strains on sorghum growth is plant genotype dependent

Sorghum is a multipurpose crop that is cultivated worldwide. Plant growth-promoting bacteria (PGPB) have important roles in enhancing sorghum biomass and nutrient uptake and suppressing plant pathogens. The aim of this research was to test the effects of the endophytic bacterial species Kosakonia radicincitans strain IAC/BECa 99, Enterobacter asburiae strain IAC/BECa 128, Pseudomonas fluorescens strain IAC/BECa 141, Burkholderia tropica strain IAC/BECa 135 and Herbaspirillum frisingense strain IAC/BECa 152 on the growth and root architecture of four sorghum cultivars (SRN-39, Shanqui-Red, BRS330, BRS509), with different uses and strigolactone profiles. We hypothesized that the different bacterial species would trigger different growth plant responses in different sorghum cultivars. Burkholderia tropica and H. frisingense significantly increased the plant biomass of cultivars SRN-39 and BRS330. Moreover, cultivar BRS330 inoculated with either strain displayed isolates significant decrease in average root diameter. This study shows that Burkholderia tropica strain IAC/BECa 135 and H. frisingense strain IAC/BECa 152 are promising PGPB strains for use as inocula for sustainable sorghum cultivation