Effect of Levels Water Salinity and Inoculation With Azospirillum and Bacillus on Some Growth and Yield Characters of Wheat (Triticum aestivum L.)

A field experiment has been conducted at the College of Agriculture - University of Al-Muthanna (Al Bandar station 2 km from the center of Al-Muthanna Governorate), during seasons 2019-2020 and 2020-2021, to study the effect of four salinity levels of irrigation water (S1, S2, S3, S4) and four treatments. of Bio Fertilization (A, B, AB, C), and knowing its effect on some characteristics of growth and yield of wheat, result showed that levels of water salinity was significant effect on growth characters, the level S1 was superior in high plant, No. tellers, leaf flag area was reached 76.03 and 82.08 cm, 358.5 and 357.2 tellers m2, 40.08 cm2 for both season on sequences. The treat of salinity S3 was superior in seed of spikes and total yields and give high means 32 and 34.42 seed spike−1, 3.850 and 4.13 ton h−1 in both season. The inoculation treatment was high significant in growth characters and the treat A was superior in plant high reached 77.78 and 77.76 cm, in tellers treat A was superior in No. tellers reached 352.4 tellers m2, the treatment AB was superior in flag leaf area and reached 40.17 cm2. The result showed superior treat AB in seeds spikes−1 reached 32.58 and 34.67 seeds spike−1 for both season, in 1000 seed weight was treat B was superior and give 33.83 and 35.08 gm in both season, the treat AB was superior in total yield its reached 3.52 and 3.82 ton h−1.

The relative susceptibility of grapevine rootstocks to black foot disease is dependent on inoculum pressure

Black foot disease of grapevines is a major economic issue for the viticulture industry worldwide. The disease is mainly associated with a complex of pathogen species within the genera Dactylonectria and Ilyonectria. The susceptibility of six grapevine rootstock cultivars to black foot disease under field conditions was assessed. Callused rootstocks of 101-14, 5C, 420A, Riparia Gloire, Schwarzmann and 3309C were planted into soil containing low natural pathogen populations or inoculated with isolates representing the species diversity in New Zealand. Disease incidence, disease severity and dry weight accumulation were assessed after 8 months of growth. Root and shoot dry weights were not significantly affected by inoculation treatment, but differed among rootstock cultivars, with cultivar 420A having the lowest root and shoot dry weight, cultivar 3309C having the largest shoot dry weight and cultivar 5C the largest root dry weight. The relative susceptibility of rootstocks differed significantly depending on whether they were grown under low natural inoculum pressure or a higher pressure in artificially inoculated soil. Schwarzmann and Riparia Gloire rootstock cultivars were the least susceptible under natural low inoculum pressure, but were the most susceptible in inoculated soil. In contrast, 5C was one of the most susceptible under low inoculum levels but was the least susceptible under high pathogen pressure. The result of the study indicate that black foot pathogen inoculum levels in soil affect the relative susceptibility of grapevine rootstocks to infection, and may have implications for the selection of rootstocks for planting.

Impact of salt and exogenous AM inoculation on indigenous microbial community structure in the rhizosphere of dioecious plant, Populus cathayana

The sex-specific physical and biochemical responses in dioecious plants to abiotic stresses could result in gender imbalance, and how to ease the current situation by microorganisms is still unclear. Using native soil where poplars were grown, growth parameters, soil physicochemical properties in the rhizosphere soil of different sexes of Populus cathayana exposed to salt stress and exogenous arbuscular mycorrhizal (AM) inoculation were tested. Besides, the sex-specific microbial community structures in the rhizosphere soil of different sexes of Populus cathayana were compared under salt stress. To identify the sex-specific microbial community characteristics related to salinity and AM symbiosis, a combined qPCR and DGGE method was used to monitor microbial community diversity. Seedlings suffered severe pressure by salt stress, reflected in limited growth, biomass, and nutrient element accumulation, especially on females. Exogenous AM inoculation treatment alleviated these negative effects, especially under salt treatment of 75 mM. Compared with salt effect, exogenous AM inoculation treatment showed a greater effect on soil physical–chemical properties of both sexes. Based on DGGE results, salt stress negatively affected fungal richness but positively affected fungal Simpson diversity index, while exogenous AM inoculation treatment showed the opposite effect. Structural equation modeling (SEM) was performed to show the causal relationships between salt and exogenous AM inoculation treatments with biomass accumulation and microbial community: salt and exogenous AM inoculation treatment showed complicated effects on elementary concentrations, soil properties, which resulted in different relationship with biomass accumulation and microbial community. Salt stress had a negative effect on soil properties and microbial community structure in the rhizosphere soil of P. cathayana, whereas exogenous AM inoculation showed positive impacts on most of the soil physical–chemical properties and microbial community status.

Inoculation With Indigenous Rhizosphere Microbes Enhances Aboveground Accumulation of Lead in Salix integra Thunb. by Improving Transport Coefficients

The application of plant–microbial remediation of heavy metals is restricted by the difficulty of exogenous microbes to form large populations and maintain their long-term remediation efficiency. We therefore investigated the effects of inoculation with indigenous heavy-metal-tolerant rhizosphere microbes on phytoremediation of lead (Pb) by Salix integra. We measured plant physiological indexes and soil Pb bioavailability and conducted widespread targeted metabolome analysis of strains to better understand the mechanisms of enhance Pb accumulation. Growth of Salix integra was improved by both single and co-inoculation treatments with Bacillus sp. and Aspergillus niger, increasing by 14% in co-inoculated plants. Transfer coefficients for Pb, indicating mobility from soil via roots into branches or leaves, were higher following microbial inoculation, showing a more than 100% increase in the co-inoculation treatment over untreated plants. However, Pb accumulation was only enhanced by single inoculation treatments with either Bacillus sp. or Aspergillus niger, being 10% greater in plants inoculated with Bacillus sp. compared with uninoculated controls. Inoculation mainly promoted accumulation of Pb in aboveground plant parts. Superoxide dismutase and catalase enzyme activities as well as the proline content of inoculated plants were enhanced by most treatments. However, soil urease and catalase activities were lower in inoculated plants than controls. Proportions of acid-soluble Pb were 0.34 and 0.41% higher in rhizosphere and bulk soil, respectively, of plants inoculated with Bacillus sp. than in that of uninoculated plants. We identified 410 metabolites from the microbial inoculations, of which more than 50% contributed to heavy metal bioavailability; organic acids, amino acids, and carbohydrates formed the three major metabolite categories. These results suggest that both indigenous Bacillus sp. and Aspergillus niger could be used to assist phytoremediation by enhancing antioxidant defenses of Salix integra and altering Pb bioavailability. We speculate that microbial strains colonized the soil and plants at the same time, with variations in their metabolite profiles reflecting different living conditions. We also need to consider interactions between inocula and the whole microbial community when applying microbial inoculation to promote phytoremediation.

Pengaruh Inokulasi Rhizobium-CMA Terhadap Pertumbuhan dan Hasil Dua Varietas Kedelai Pada Tanah Entisol

A research to observe the influence of Rhizobium and Vesicular Arbuscular Mycorrhyzae inoculation on growth and yield of Edamame and Wilis varieties of soybeans in Entisol soil. The research was conducted in the green house of Agriculture Faculty, Muhammadiyah University of Yogyakarta, from June to September 2003. The field experiment was arranged in 4x2 factorial Completely Randomized Design (CRD) with three replications. The first factor was inoculation treatment which contains four levels consisted of: (1) without inoculation; (2) Rhizobium inoculation; (3) VAM inoculation and (4) Rhizobium-VAM inoculation. The second factor was the kind of varieties namely Edamame and Wilis. There were 24 research units which contain 12 polybags of each unit. The result of this research showed that there was no interaction between inoculation treatments and kinds of varieties to all of parameters, except the percentage of mycorrhizae infection. Inoculation of Rhizobium and VAM significantly increased the growth and yield of Wilis variety. The 100 grains weight of Edamame variety was 23.21 g and Wilis variety was 7.49 g. Inoculation of Rhizobium on Wilis variety was more compatible than Edamame. Endogenus VAM application on Edamame variety was more compatible than VAM isolates inoculation.

Combination of arbuscular mycorrhizal fungi and phosphate solubilizing bacteria on growth and production of Helianthus tuberosus under field condition

In this work, the effects of co-inoculation between an arbuscular mycorrhizal fungus (AMF) and a phosphate solubilizing bacteria (PSB) to promote the growth and production of sunchoke under field condition were investigated during 2016 and 2017. Four treatments were set up as follows: plants without inoculation, with AMF inoculation, with PSB inoculation and with co-inoculation of PSB and AMF. The results showed the presence of PSB and AMF colonization at the harvest stage in both years. This suggested the survival of PSB and successful AMF colonization throughout the experiments. According to correlation analysis, PSB positively affected AMF spore density and colonization rate. Also, both AMF and PSB positively correlated with growth and production of sunchoke. Co-inoculation could enhance various plant parameters. However, better results in 2016 were found in co-inoculation treatment, while AMF inoculation performed the best in 2017. All of these results suggested that our AMF and PSB could effectively promote growth and production of sunchoke under field conditions. Such effects were varied due to different environmental conditions each year. Note that this is the first study showing successful co-inoculation of AMF and PSB for promoting growth and yield of sunchoke in the real cultivation fields.

Effects of Herbaspirillum Sp. P5–19 Assisted With Alien Soil Improvement on the Phytoremediation of Copper Tailings by Vetiveria Zizanioides

This study investigated examined the potential of Herbaspirillum sp. p5-19 (p5-19) assisted with alien soil improvement on improving stress tolerance and enhancing the accumulation of Mn, Cu, Zn and Cd by vetiver grass (Vetiveria zizanioides). Phytoremediation potential was evaluated by plant biomass and the ability of plant to absorb and transfer heavy metals. Results showed that the biomass was increased by 19.64%–173.81% in p5-19 inoculation treatments with and without alien soil improvement compared with control. Meanwhile, photosynthetic pigment contents were enhanced in co-inoculation treatment (p5-19 with alien soil improvement). In addition, the malondialdehyde (MDA) content was decreased, and the activities of antioxidant enzymes such as ascorbate peroxidase (APX), superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were increased in p5-19 treatment, thereby alleviating the oxidative stress. Moreover, co-inoculation significantly (p<0.05) increased the concentrations of Mn, Cu, Zn and Cd in the roots and shoots of vetiver grass. In particular, the highest concentration of Mn, Zn and Cd in the shoots (roots) were obtained in C10 under p5-19 inoculation (C10B), which were 4.44– (2.71–), 4.73– (3.87–) and 5.93– (4.35–) fold as that of the controls, respectively. These results provided basis for the change of phytoremediation ability of vetiver grass after inoculation. We concluded that p5-19 assisted with alien soil improvement was a potential strategy for enhancing phytoremediation ability in tailings.

Multigene editing reveals that MtCEP1/2/12 redundantly control lateral root and nodule number in Medicago truncatula

The multimember CEP (C-terminally Encoded Peptide) gene family is a complex group that is involved in various physiological activities in plants. Previous studies demonstrated that MtCEP1 and MtCEP7 control lateral root formation or nodulation, but these studies were based only on gain of function or artificial miRNA (amiRNA)/RNAi approaches, never knockout mutants. Moreover, an efficient multigene editing toolkit is not currently available for Medicago truncatula. Our quantitative reverse transcription–PCR data showed that MtCEP1, 2, 4, 5, 6, 7, 8, 9, 12, and 13 were up-regulated under nitrogen starvation conditions and that MtCEP1, 2, 7, 9, and 12 were induced by rhizobial inoculation. Treatment with synthetic MtCEP peptides of MtCEP1, 2, 4, 5, 6, 8, and 12 repressed lateral root emergence and promoted nodulation in the R108 wild type but not in the cra2 mutant. We optimized CRISPR/Cas9 [clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9] genome editing system for M. truncatula, and thus created single mutants of MtCEP1, 2, 4, 6, and 12 and the double mutants Mtcep1/2C and Mtcep5/8C; however, these mutants did not exhibit significant differences from R108. Furthermore, a triple mutant Mtcep1/2/12C and a quintuple mutant Mtcep1/2/5/8/12C were generated and exhibited more lateral roots and fewer nodules than R108. Overall, MtCEP1, 2, and 12 were confirmed to be redundantly important in the control of lateral root number and nodulation. Moreover, the CRISPR/Cas9-based multigene editing protocol provides an additional tool for research on the model legume M. truncatula, which is highly efficient at multigene mutant generation.

PENGARUH MEDIA DENGAN KRITERIA SALINITAS TANAH SALIN DAN NON SALIN TERHADAP EFEKTIVITAS DAN INFEKTIVITAS ISOLAT BAKTERI Rhizobium sp TOLERAN SALINITAS PADA TANAMAN KEDELAI (Glycine max L. Merril)

Demand for the consumption of soybeans in 2014 was very high amounting to 10.91 kg capita-1 year-1 while soybean production was only 955 thousand tons. Soybean production can be increased by expanding the planting area including saline land areas. The use of soil microbes Rhizobium sp can help overcome this because Rhizobium sp can find symbiosis with soybean plants so that it allows the absorption of nitrogen nutrients for the growth of soybean plants. This study was aimed to determine and analyze the effect of saline soil on the effectiveness and infectivity of Rhizobium sp. inoculated to soybean plants on soil chemical and biological properties and plant growth. The study was conducted using a randomized block design consisting of 10 treatments and 3 replications. The results showed that the bacterial inoculation gave better plant growth than the control treatment on saline and non-saline soils. The high number of colonies was able to increase the number of effective root nodules and N-plant uptake and produced good plant growth with the best results. The inoculation treatment of isolate 12 on non-saline soil yielded N absorption value of 0.32 g plant-1, effective root nodules of 87.67 g plant-1, effective root nodule dry weight of 0.74 g plant-1, and plant height of 134.3 cm. On the biological properties of isolate 12 inoculation treatment on non-saline soil had the highest yield for the number of isolate colonies of 305.45 × 105 CFU mL-1.