Combined Inoculation Research Articles

Bioactive compounds in edible flowers of garden pansy in response to irrigation and mycorrhizal inoculation

ABSTRACT Edible flowers have been increasingly used in the Brazilian gastronomy because they are considered functional foods with high antioxidant potential. Studies on the management of cultivation of edible flowers to increase the production of bioactive compounds have been developed aiming at the improvement of production systems. The objective of this work was to evaluate the production of bioactive compounds in garden pansy (Viola wittrockiana Gams ex Nauenb. & Buttler) plants submitted to different levels of irrigation and mycorrhizal inoculation. The greenhouse experiment was conducted in randomized blocks in a 2x5 factorial design with the presence and absence of mycorrhizal inoculation in combination with 5 levels of water evaporation (120%, 100%, 80%, 60% and 40%) replaced by irrigation, totaling 10 treatments with 6 replicates. The contents of bioactive compounds (total phenolic compounds, flavonoids and total anthocyanins) present in the flowers, collected over the reproductive period, were evaluated. There was a significant interaction between the factors mycorrhizal inoculation and irrigation levels by F test (p < 0.05) for total flavonoids and anthocyanins. The best results in the production of bioactive compounds were obtained for irrigation at the 100% replenishment level of water evaporation without the presence of mycorrhizal inoculation.

IMPACT OF BIOFERTILIZERS AND BIOPESTICIDES ON THE GROWTH AND YIELD OF JASMINE (JASMINUM SAMBAC L.)

Jasmine (Jasminum sambac L.), one of the most important fragrant flowers widely cultivated in India, is seriously damaged by numerous insect pests. To devise a suitable Integrated Pest Management (IPM) module, a study using biofertilizers and biopesticides separately and in combination was conducted in two-year-old jasmine plants in a field at Seeragampatty village during September 2017 to February 2018. The experiment was set up in Randomized Block Design (RBD) with nine treatments for both biofertilizers and biopesticides with three replications. The results strongly endorse the integrative approach for the optimum growth and yield of jasmine plants which was produced by the combined inoculation of Azospirillum sp. and Phosphobacterium sp. along with vermicompost. The infestation of budworms, red mites and white flies were reduced with the application of biopesticides (Trichoderma sp., Bacillus sp. and Paecilomyces sp.) in combination with biofertilizers. It was also found that there was no infestation of budworms during November 2017 and January 2018, and that of red mites in November 2017. The population of white flies was fluctuating throughout the study period. From the findings of present investigation, it has been concluded that the amalgamation of suitable biofertilizers and biopesticides managed the insect pests in a better way and increased the growth and yield of jasmine. Keywords: Jasmine, Biofertilizers, Biopesticides, Growth, Yield, IPM.

Individual and interactive role of Trichoderma viride and arbuscular mycorrhizal fungi on growth and pigment content of onion plants.

The study of interactions between beneficial micro-organisms associated with plant roots is important, because such interactions might either enhance or inhibit the beneficial effects of individual species. The effect of the combined inoculation of arbuscular mycorrhizal (AM) fungi and a biocontrol fungus (Trichoderma viride) on different growth parameters and chlorophyll a,b, carotenoids, total chlorophyll and total pigments of onion (Allium cepa) plants was studied under glasshouse conditions. The results proved that AM fungi and T. viride are compatible with each other and their combined use was effective not only in improving onion growth parameters such as fresh and dry weights, root and shoot lengths and leaf area but also increasing total chlorophyll, carotenoids and total pigments content in onion leaves. Where, inoculation of onion plants by AM fungi and T. viride alone or in combination significantly increased bulb diameters of onion plants 20, 12·5 and 17·5% increase; respectively, when compared with control ones. Also percentage of AM fungal colonization increased greatly with T. viride inoculation. Therefore, AM fungi and T. viride could be a good alternate of chemical fertilizer for improving the growth of onion. SIGNIFICANCE AND IMPACT OF THE STUDY: Significance and Impact of the Study: The need for increasing agricultural productivity and quality has led to an excessive use of chemical fertilizers; creating serious threats to human health and the environment. The use of biofertilizers is an alternative for sustaining high production with low ecological impact. Thus the goal of this study was to propose a biological technique using arbuscular mycorrhizal symbiosis and Trichoderma viride (plant-microbe interaction) for increasing plant growth that represent a great opportunities for recent agricultural practices. This may be an indication displaying the AM and Trichoderma significance for plant progress and growth.

Interaction of Colletotrichum coccodes and Verticillium dahliae in pepper plants

Wilting of sweet pepper plants is leading to significant yield losses in organic cultivation in glasshouses in the Netherlands. Verticillium dahliae was consistently isolated from affected plants and is known to cause wilting of plants. While sampling sweet pepper plants, root discoloration and damage of the root cortex were observed. Colletotrichum coccodes was isolated from affected roots. To study the co-occurrence and interaction of both pathogens, sweet pepper plants with, and without wilting symptoms were collected from the glasshouse. V. dahliae was only isolated from plants with wilting symptoms, while C. coccodes was also found on symptomless plants. Single or combined inoculations with V. dahliae and C. coccodes were performed on pepper seedlings to study the pathogenicity and the interaction of both pathogens. Symptom development was evaluated and fungal colonization was measured in the roots and stem with real-time PCR. V. dahliae induced stunted growth, while C. coccodes did not induce symptoms on the shoot. C. coccodes reduced root weight when plants grew under suboptimal conditions but under optimal conditions for plant growth, C. coccodes reduced V. dahliae colonization and symptom development. In conclusion, V. dahliae is the causal agent of wilting of pepper plants and C. coccodes is a weak pathogen, with antagonistic or neutral effects on symptom development and colonization by V. dahliae. This work can contribute to the understanding of soilborne diseases and their interaction with each other.

Arbuscular mycorrhizal fungi (Glomus intraradices) and diazotrophic bacterium (Rhizobium BMBS) primed defense in blackgram against herbivorous insect (Spodoptera litura) infestation

In the changing scenario of agriculture, plants are exposed to various biotic and abiotic stresses. Induction of both constitutive and inducible defense systems was noticed in plants exposed to stress. As a major defense response, production of phenolics and superoxide radicals quenching enzymes is accelerated in plants under stress. These metabolites production intensified further when arbuscular mycorrhizal fungi (AMF) infected plants are subjected to stress. With this background, we conducted experiments to explore the impacts of Glomus intraradices and Rhizobium on the stimulation of defense in blackgram against Spodoptera litura. Uninoculated plants accumulated considerable quantity of defense metabolites like phenolics, lignin and superoxide radicals quenching enzymes such as superoxide dismutase, peroxidase, catalase, phenylalanine ammonium lyase, and polyphenol oxidase constitutively. While production of these defense metabolites primed strongly due to G. intraradices inoculation. These defense responses augmented further when G. intraradices colonized plants were exposed to S. litura. Though the combined inoculation with G. intraradices and Rhizobium improved the defense response, the effect was more pronounced due to single inoculation with G. intraradices. Results of in vitro leaf feeding bioassay showed that the feeding capacity of S. litura reduced (36.32%) significantly due to feeding G. intraradices infected plants. These outcomes revealed that tolerance against S. litura in blackgram could be primed by mycorrhizal inoculation. This is the first report to state that G. intraradices besides improving nutrient use efficiency, also accelerates defense response in blackgram against S. litura. Hence, AMF could be recommended as a bioprotectant against S. litura in blackgram.

QUALITY AND AEROBIC STABILITY OF FERMENTED ROLLED CORN GRAIN IN UNDER COMBINED INTRODUCTION OF PROBIOTIC STRAINS OF LACTIC ACID BACTERIA AND REPRESENTATIVES OF BACILLUS SUBTILIS

Objective. To find out the effect of combined introduction of probiotic strains of lactic acid bac-teria and Bacillus subtilis on the quality and aerobic stability of fermented rolled corn grain. Methods. Microbiological, zootechnical. Results. According to the results of organoleptic analysis, preserved rolled corn grain of the experimental and control variants had a preserved texture with a pleasant fruity odour. Preservation of crude fibre in the raw material of the experimental variants treated with Bacillus subtilis ВРT-B1 and under the combined use of lactic acid bacteria with aero-bic bacilli was higher by 10.0 % and 3.3 %, respectively, as compared to positive control parame-ters (Subtikon grain processing). The protein content in the experimental variants and the positive control was higher by 2.4–7.2 % than in the control variant of the feed (without the use of microor-ganisms). After aerobic exposure of feed for 14 days, preservation of crude fibre in all variants be-gan to decrease, however, the greatest losses (20 %) were noted in the control variant (without in-troduction of bacteria). The highest protein losses were observed in the control variant (3.8 %).After aerobic exposure, acidity in all variants of the experiment remained in the optimal range of pH 3.9–4.2. At day 70 of feed preservation, an increase in the number of lactic acid bacteria by 2–3 orders of magnitude in samples of experimental variants and positive control in comparison with this parameter in the raw material was noted. After air access to preserved rolled corn grain for 14 days, the lowest number of lactic acid bacteria was observed in absolute control, the high-est — in the variant with the combined inoculation by strains of Lactobacillus plantarum КT-L18/1 and Bacillus subtilis ВРT-B1. No pathogenic and butyric acid bacteria were detected. Conclusi-on. The combined use of probiotic strains of lactic acid bacteria and Bacillus subtilis to preserve corn grain contributes to the preservation of nutrients, the establishment and maintenance of an op-timal level of acidity, prevents aerobic food spoilage.

EFFECT OF GOAT’S-RUE RHIZOBIA ON THE FORMATION AND FUNCTIONING OF THE SOYBEAN – BRADYRHIZOBIUM JAPONICUM 634B SYMBIOSIS

Objective. Study the peculiarities of nodule formation upon the formation of the symbiotic sys-tem soybean-Bradyrhizobium japonicum 634b, as well as the symbiotic nitrogen-fixation ability and plant growth and development under the influence of goat’s-rue rhizobia. Methods. Microbiologi-cal, physiological, statistical, gas chromatography. Results. In green house experiments, using sand as a substrate for growing plants, the mixed microbial cultures combining soybean nodule bacteria B. japonicum 634b and goat’s-rue nodule bacteria R. galegae 0702 or R. galegae 0703 in the ratio of 1 : 1 differed from the monoculture bradyrhizobium by their influence on the nodulation, nitro-gen-fixation ability of soybean-rhizobial symbiosis and development of soybean plants (variety Almaz). Increased nodulation activity in the primordial leaf and budding phases, as well as a signif-icant decrease in the level of symbiosis nitrogen fixation during budding, were observed when used in binary bacterial compositions of strain R. galegae 0703. These rhizobia of goat’s-rue suppressed the development of the root system of soybeans, but had no significant effect on the formation of the aerial part of the plants throughout the observation period. R. galegae 0702 strain slightly slowed the formation of nodules by bacteria in the primordial leaf phase, which caused a decrease in the number of soybean plants that formed symbiosis with B. japonicum 634b. Goat’s-rue nodule bacte-ria R. galegae 0702 improved the formation of the root system, and stimulated the growth and de-velopment of the aerial part of the macro symbiont in the phase of two trigeminal leaves. Conclu-sion. Combined inoculation of the rhizobia of goat’s-rue with nodule bacteria B. japonicum 634b showed a multidirectional effect on the formation of symbiosis by soybean plants of variety Almaz and functioning of soybean rhizobial symbiosis. The nature of the influence of R. galegae depended on their strain affiliation.

Seed inoculation with Penicillium bilaiae and Bacillus simplex affects the nutrient status of winter wheat

Penicillium bilaiae is a P-solubilizing fungus that is used as an inoculant to promote plant growth or P uptake in various crops. Bacillus simplex has also been shown to have positive effects on different crops. However, the interaction between these inoculants and their effect on plant growth and acquisition of nutrients other than P are poorly understood. In two pot trials at different levels of inorganic P fertilization, we investigated the effect of single and combined inoculation with Penicillium bilaiae and Bacillus simplex on the growth and nutrient status of winter wheat (Triticum aestivum L.), as well as inoculant persistence and colonization. Quantitative PCR analyses revealed that both inoculants colonized and persisted on seeds and roots. The microbial inoculants increased the P concentration in root biomass at all P levels and concentrations of Mg, Mn and S in shoot biomass in low-P soil, without however having any significant effect on plant growth. Furthermore, unlike the single inoculations, the combined inoculation increased P uptake in low-P soil. These results indicate that use of the studied microbial inoculants has the potential to improve the nutritional status of winter wheat in low-P soil, especially when applied as a consortium.

Combined application of native mycorrhizal and cellulolytic fungi to manage drought effects on maize

Drought become the foremost abiotic stress limiting plant growth and leading to crop-yield loss. This study was aimed to evaluate the effect of native arbuscular mycorrhizal (AM) and cellulolytic fungi (CF) on the growth, yield, mycorrhizal colonization, and the phosphorous (P) and proline contents of maize under drought. This study was conducted using a 3 x 3 factorial arranged in randomized complete block design with three replications The treatments were inoculation of native AM fungi (no AM fungi, Acaulospora tuberculata, and Gigaspora cf. gigantea) and native celluloltic fungi (no CF, Talaromyces pinophilus strain MR107 and Talaromyces pinophilus isolate OK3SP103P) evaluated under 50% field capacity (FC). Our results clearly indicated that increasing plant height, plant diameter, mycorrhizal colonization, and P content and decreasing proline content were affected either by native AM or cellulolytic fungi, but dry weight of 100-grain was only increased by native cellulolytic fungi. Combined inoculation of native AM and cellulolytic fungi improved P content and mycorrhizal colonization. Gi. cf. gigantea and T. pinophilus strain MR107 were more potential native inoculants to eliminate negative effect of water stress on maize.

Arbuscular Mycorrhizal Fungus Improves Rhizobium–Glycyrrhiza Seedling Symbiosis under Drought Stress

Rhizobia and arbuscular mycorrhizal (AM) fungi can potentially alleviate the abiotic stress on the legume Glycyrrhiza (licorice), while the potential benefits these symbiotic microbes offer to their host plant are strongly influenced by environmental factors. A greenhouse pot experiment was conducted to investigate the effects of single and combined inoculation with a rhizobium Mesorhizobium tianshanense Chen and an AM fungus Rhizophagus irregularis Walker &amp; Schuessler on Glycyrrhiza uralensis Fisch. seedling performance under different water regimes. Drought stress inhibited rhizobium nodulation but increased mycorrhizal colonization. Furthermore, co-inoculation of rhizobium and AM fungus favored nodulation under both well-watered and drought stress conditions. Glycyrrhiza seedling growth showed a high mycorrhizal dependency. The seedlings showed a negative growth dependency to rhizobium under well-watered conditions but showed a positive response under drought stress. R. irregularis-inoculated plants showed a much higher stress tolerance index (STI) value than M. tianshanense-inoculated plants. STI value was more pronounced when plants were co-inoculated with R. irregularis and M. tianshanense compared with single-inoculated plants. Plant nitrogen concentration and contents were significantly influenced by inoculation treatments and water regimes. R. irregularis inoculation significantly increased plant shoot and root phosphorus contents. AM fungus inoculation could improve Glycyrrhiza plant–rhizobium symbiosis under drought stress, thereby suggesting that tripartite symbiotic relationships were more effective for promoting plant growth and enhancing drought tolerance.

Response of arbuscular mycorrhizal fungi and phosphorus solubilizing bacteria to remediation abandoned solid waste of coal mine

Coal is the vital resource of energy in China, but abandoned coal ash and gangue lead to the degradation of vegetation cover and reduce soil quality. Both arbuscular mycorrhizal fungi (AMF) and phosphate solubilizing bacteria (PSB) play a key role in biogeochemical cycle such as soil organic matter decomposition, nutrition release, and energy flow. To improve and reclamation the soil quality and ecological efficiency of the coal mining waste, we investigated the effects of an AMF strain (Glomus mosseae) and a PSB strain (Pantoesstewarti) on phytate mineralization and subsequent transfer to the host plant (Medicago sativa L.) using a two-compartment microcosm with a central 30 mm nylon mesh barrier. The results showed that significantly higher available P (AP), above ground biomass (AGB) and underground biomass (UGB) were in combined inoculation of AMF-PSB than other treatments in root and hyphae compartment. The microbial inoculum of the AMF or PSB had a significant influence on soil acid phosphatase activities (ACP). AMF-PSB enhanced phytate mineralization, improved plant biomass. AP and ACP positively influenced the AGB and UGB. AMF-PSB could be used as bioinoculant to enhance sustainable production of the plant in abandoned solid waste of coal mine.

Effect of different application forms of efficient microorganisms on the agricultural productive of two bean cultivars

The use of Efficient Microorganisms (EM) can be an effective alternative to improve plant growth and yield in the bean cultivation. Therefore, different forms of application of efficient microorganisms were evaluated in the production of two cultivars of the common bean from November of 2013 to March of 2014. Two factors were studied; the first one was comprised of the two cultivars, Velazco Largo (VL) and Cuba Cueto (CC-25-9-N). The second factor consisted of four treatments with EM; without EM (control), soil inoculation (100 mL L-1), foliage applications (100 mL L-1), and the combined soil inoculation (100 mL L-1) plus foliar applications (100 mL L-1). The experiment was carried out in a randomized block design, in factorial outline 2×4, with three repetitions. The agronomic indicators were evaluated as the number of leaves per plant, the height of plants, number of pods per plant, number of seeds per pod, the mass of 100 seeds (g) and the yield (t ha-1). The results showed that the different forms of application of efficient microorganisms stimulated the agronomic indicators evaluated in both crops. The associated applications between the inoculation of the soil and foliage applications of efficient microorganisms provided better results, producing increments in the yield of 1.13 t ha-1 in VL and 2.15 t ha-1 in CC-25-9-N.

Residual effect of zinc applied to rice on zinc nutrition of succeeding wheat crop inoculated with zinc solubilizing microbial consortium

Large scale deficiency of Zn results in low crops yields and the problem of Zn malnutrition in humans and livestock. To economize crop production on Zn deficient soils, two-year field experiments were undertaken with two wheat varieties to evaluate the performance of seed inoculation with a consortium of three bacterial strains in combination with varying doses of Zn fertilizer applied to 1 year rice crop on yields, Zn concentration and Zn uptake of wheat. Seed coating of wheat with bacterial consortium significantly increased grain yields, Zn concentration and uptake in grains and straw and total Zn uptake over the control. It also helped to increase the apparent recoveries of soil applied Zn fertilizer to 1 year rice by succeeding wheat crops and DTPA extractable Zn in soil after 2 year wheat in comparison to the control. Seed inoculation in combination with low dosage of Zn also significantly decreased phytic acid: Zn ratio but increased methionine concentration in wheat grains.

Grain refinement of hypoeutectic Al-7wt.%Si alloy induced by an Al–V–B master alloy

The current study investigates the grain refinement of an Al-7wt%Si alloy with addition of Al–V–B master alloy. It is found that the Al–V–B master alloys can overcome the Si poison effect on grain refinement and refine the as cast grain structure of the Al-7wt%Si alloy effectively. A remarkable grain refinement has been achieved by using an Al–3V–1B master alloy with the combined inoculation of 0.015 wt% V and 0.005 wt% B, compared to that obtained by separate inoculation of Al–5V and Al–3B master alloys with the same concentrations of V and B. The corresponding XRD analysis on the Al–5V and Al–3V–1B master alloys and extracted particles from the Al–3V–1B master alloy show that the active nuclei are VB2 particles. The employment of the new Al–3V-1.28B master alloy optimized according to the atomic ratio of V:B = 1:2 produced the finest grain size in the Al-7wt.%Si alloy compared with the commercial Al–3Ti–1B and Al–5Ti–1B master alloys. This study indicates that the Al–V–B master alloy has the potential to be an effective grain refiner for Al–Si alloys.

Effect of Co-Inoculation with Pichia fermentans and Pediococcus acidilactici on Metabolite Produced During Fermentation and Volatile Composition of Coffee Beans

Removal of the mucilage layer of coffee fruits by a fermentation process has became an interesting strategy to improve coffee quality, which is able to assist the formation of flavored molecules. In this study, four sets of inoculation protocols were evaluated using ripe and immature coffee fruits, respectively, including (i) pure culture fermentation with Pichia fermentans, (ii) pure culture fermentation with Pediococcus acidilactici, (ii) combined fermentation with P. fermentans and P. acidilactici, and (iv) spontaneous, non-inoculated control. The initial pulp sugar concentration of ripe coffee fruits (0.57 and 1.13 g/L glucose and fructose content, respectively) was significantly higher than immature coffee pulp (0.13 and 0.26 g/L glucose and fructose content, respectively). Combined inoculation with P. fermentans and P. acidilactici of ripe coffee beans increased pulp sugar consumption and production of metabolites (lactic acid, ethanol, and ethyl acetate), evidencing a positive synergic interaction between these two microbial groups. On the other hand, when immature coffee fruits were used, only pure culture inoculation with P. fermentans was able to improve metabolite formation during fermentation, while combined treatment showed no significant effect. Altogether, 30 volatile compounds were identified and semi-quantified with HS- solid phase microextraction (SPME)-gas chromatography coupled to mass spectrophotometry (GC/MS) in fermented coffee beans. In comparison with pure cultures and spontaneous process, combined treatment prominently enhanced the aroma complexity of ripe coffee beans, with a sharp increase in benzeneacetaldehyde, 2-heptanol, and benzylalcohol. Consistent with the monitoring of the fermentation process, only P. fermentans treatment was able to impact the volatile composition of immature coffee beans. The major impacted compounds were 2-hexanol, nonanal, and D-limonene. In summary, this study demonstrated the great potential of the combined use of yeast and lactic acid bacteria to improve fermentation efficiency and to positively influence the chemical composition of coffee beans. Further studies are still required to investigate the mechanisms of synergism between these two microbial groups during the fermentation process and influence the sensory properties of coffee products.

Earthworms and mycorrhization increase copper phytoextraction by Canavalia ensiformis in sandy soil

Phytoremediation is an alternative for remediating soil contamination by copper, and its efficiency has been shown to increase when arbuscular mycorrhizal fungi (AMF) and earthworms are separately inoculated into the soil. This study evaluated the isolated and combined effects of inoculating earthworms and arbuscular mycorrhizal fungi into a sandy soil on copper phytoremediation by Canavalia ensiformis. The plants were grown in a greenhouse in soil contaminated with 100 mg Cu kg−1 with and without being inoculated with the arbuscular mycorrhizal fungus Rhizoglomus clarum and the earthworm Eisenia andrei. The availabilities of solid-phase Cu and other nutrients in the soil solution and plant growth were evaluated along with Cu phytotoxicity based on photochemical efficiency and oxidative stress enzyme activity. Accumulation of Cu and other nutrients in the shoots and roots; mycorrhizal colonization, nodulation, and reproduction; and Cu accumulation in the earthworm tissues were also evaluated. The copper caused photosynthetic and biochemical damage that reduced the shoot dry weight by 44% and the root dry weight by 29%. However, the arbuscular mycorrhizal fungus alleviated the Cu toxicity to the plant and increased the shoot dry weight by 81% in the contaminated soil. The earthworms increased the Cu uptake and translocation to the shoot by 31%. The combined presence of the arbuscular mycorrhizal fungus and earthworms in the contaminated soil increased the growth and Cu content of the aerial plant tissues, yielding a 200% increase in Cu accumulation (metal content × biomass) in the C. ensiformis shoots. Combined inoculation with earthworms and arbuscular mycorrhizal fungi increased copper phytoextraction by Canavalia ensiformis in a sandy soil.

Effect of integrated nutrient management on nutrient supply, productivity and soil fertility in Pearlmillet (Pennisetum glaucum L.)

An experiment was conducted for 2 years (2018 and 2019) at Oilseed Research Farm, Kalyanpur, C. S. A. University of Agriculture and Technology, Kanpur, Uttar Pradesh, India to evaluate the effect of nutrient management practices on growth and yield of pearl millet (Pennisetum glaucum (L) R. Br. Emend. Stuntz.). Highest yield was observed in 5t FYM/ha application over control. Each unit increase in N level led to significant increase in growth, yield attributing characters and yield of pearlmillet. The maximum grain yield (24.2q/ha) was recorded with highest N level. Combined inoculation of Azospirillum + PSB increased the growth, yield attributes and yields significantly. The monetary returns were found in similar trends. Application of organic manure and bio-fertilizers resulted in desirable post-harvest soil status with more organic carbon (OC), Nitrogen (N), Phosphorus (P) and Potash (K).

Effect of Management Practices on Growth and Productivity of Chip Bud Raised Sugarcane (Saccharum offcinarum L.)

Field investigations were carried out during early seasons of 2014 to 2016 at Sugarcane Research Station, Cuddalore to ascertain the effect of intra-row spacings doses of NPK, addition of bio- inoculants in combination with the practice of topping under conventional method of flooding irrigation forchipbud raised sugarcane seedlings. The adoption of 30 cm intra-row spacings + 100% dose of NPK+ topping treatment registered significantly maximum number of tillers per hectare, however, the maintenance of 45 cm intra- row spacings + 100 % recommended dose of NPK + topping registered the maximum values of varied growth, yield parameters viz., cane length (289 and 282 cm), cane girth (2.79 and 2.66 cm) individual cane weight (2.06 and 1.97kg) and millable canes (1,27,600 and 1,23,600) cane (140.43 and 129.94tha-1)and sugar yield (16.86 and 15.67tha-1).

Effect of rhizospheric and endophytic bacteria with multiple plant growth promoting traits on wheat growth.

The present study focused on the characterization of plant growth promoting rhizospheric (R) and endophytic (E) bacteria and their impact on wheat cultivars growth. In this study, 400 strains were isolated from the rhizosphere soil (250 isolates) and surface-sterilized roots (150 isolates) of wheat and screened for their ability to plant growth promotion (PGP) traits. Four R isolates and four E isolates with different ability were selected to investigate the interaction between R and B bacteria associated with wheat cultivars under in vitro and greenhouse conditions. Plant growth parameters were found to be enhanced by the combined inoculation of two groups of R and E bacteria compared to individual inoculations (respectively 33.7 and 37.8% increase in root and shoot dry weight), suggesting that PGP rhizobacteria acted synergistically with PGP endophytes in phosphate solubilization. Compared to inoculation with phosphate-solubilizing bacteria (PSB) or indole-3-acetic acid producer bacteria (IAA-PB), inoculation by bacteria with multiple PGP properties (PSB and IAA-PS) showed higher promotion capacity. Also, in greenhouse assay, bacterial inoculation had a positive effect on the soil dehydrogenase (70.2%) and phosphatase (52.2%) activity. It seems PGP traits do not work independently of each other but additively as it was suggested in the "synergistic hypothesis" that multiple mechanisms are responsible for the plant growth promotion and increased yield. Findings of this study could improve the current bio-fertilizer production procedure in research and related industries.

Plant beneficial rhizospheric microorganisms (PBRMs) mitigate deleterious effects of salinity in sesame (Sesamum indicum L.): Physio-biochemical properties, fatty acids composition and secondary metabolites content

Salinity is serious environmental stress that highly affects the quantity and quality of herbal products. In this study a pot experiment was carried out in greenhouse to investigate the interactive effects of Azospirillum lipoferum and Piriformospora indica on growth attributes and secondary metabolites production of sesame (Sesamum indicum L.) under saline condition. The applied microorganisms raised the ability of sesame in absorption of essential nutrients. The highest concentration of N (24.33 and 39.65 mg g−1 DW in shoot and root, respectively), K (23.13 and 18.74 mg g−1 DW in shoot and root, respectively) and P (11.08 and 13.70 mg g−1 DW in shoot and root, respectively) were observed in co-inoculated plants under non-stress condition. The results showed that increasing NaCl concentration in irrigation water (from 0 to 120 mM), significantly disordered the absorption and distribution of water and minerals. In addition, salt-induced reactive oxygen species lead to oxidative damage of sesame plants, consequently, 3.29 and 1.87 fold increases were observed in the amount of malondialdehyde (MDA) and electrolyte leakage (EL), respectively. During salt stress, activity of protective enzymes and amount of non-enzymatic antioxidants were dramatically raised. This study showed that inoculation of sesame with PBRMs can provide salt-tolerance by changing in physio-biochemical responses. Under saline condition, inoculation with Al and Pi resulted an enhancement of relative water content (up to 20%), maximum photochemical quantum yield of PSII (Fv/Fm) (up to 25%), antioxidant enzyme activity, nutrient absorption, proline (36–65%) and secondary metabolite contents, DPPH radical scavenging activity (18–22%) and linoleic acid. Conversely, the amount of MDA (up to 35%), EL (up to 23%), Na+ (up to 66 and 59% in shoot and root, respectively) as well as oleic/linoleic acids ratio were significantly decreased via microbial treatments. However, combined inoculation (Al + Pi) was generally more effective in alleviation of salinity deleterious effects than individual inoculation.