Seed Inoculation

Seed inoculation with phosphorus-solubilizing fungi along with P2O5 levels considerably influenced plant height, number of leaves per institute, dry out matter product, cob length, grain weight per cob, 1000 grain weight, grain yield, and tissue nutrient content (Northward, P, K, Zn, and Atomic number 26) at teaseling of leaves and harvest of whole plant and P uptake at harvest.

From: New and Time to come Developments in Microbial Biotechnology and Bioengineering , 2018

Biofertilizers: "An ace in the hole" in medicinal and aromatic plants cultivation

Pratibha Tripathi , Akanksha Singh , in Biofertilizers, 2021

19.5.1 H2o stress (inundation or drought)

Under drought or water deficit conditions, seed inoculation with Pseudomonas fluorescence results in enhanced plant growth and yield attributes of Catharanthus roseus as compared to untreated plants (Jaleel et al., 2007). Inoculation with ACC deaminase containing the Bacillus subtilis strain defended Trigonella plants under farthermost drought stress weather by improving the plant weight, nodulation, and nutrient status of the plant (Barnawal et al., 2013).

Inundation or heavy rainfall leads to waterlogging stress and affects various institute physiological activities, which results in reduced growth and yield in several plant species including MAPs (Sairam et al., 2009; Barnawal et al., 2012). Also, soil waterlogging conditions create a reducing soil environment due to hypoxia (oxygen deficiency), which leads to reduced found nutrient uptake and imbalance in many crucial physiological activities such as irregular stomatal closure, inhibition in photosynthesis, retarded plant growth, and hence overall decreased yield. Reports suggest that microbial inoculation protected plants from the adverse furnishings of waterlogging conditions such as germination of stress ethylene (by deamination of ACC), induced lipid peroxidation, proline concentration, and reduced chlorophyll concentration. In a report, protection of Ocimum sanctum plants with the inoculation of ACC deaminase containing PGPRs under waterlogging stress conditions lowered the root ethylene levels with improved establish growth and yield (Barnawal et al., 2012).

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Nitrogen Fixation and Agricultural Exercise

K.W. O'Hara , ... P.H. Graham , in Nitrogen Fixation at the Millennium, 2002

3.4 Strain persistence and competitiveness of soil rhizobia

At rates of tenthree to 106 rhizobia applied per seed, inoculation should supply upward to 8 × tenten rhizobia per ha [107]. Where at that place are no soil problems and few indigenous rhizobia, this should be more than sufficient to ensure abundant nodulation, with well-nigh of the nodules due to the inoculant strains formed in the offset year [108]. Every bit these nodules senesee toward the end of the first growing flavour, further large numbers of the inoculant strain(s) will be released into the soil. Bever and Simms [109] propose that bacteroids are incapable of reproduction, and thus that the kin of the inoculant strain(southward) derive no pregnant do good from these initially high nodule-occupancy rates. This ignores the high % viability of the rhizobia recovered from determinate nodules, and the survival of bacteria from the infected only non-nitrogen-fixing regions of the indeterminate nodule [110]. Recently, Muller et al. [111] have also reported a potential for redifferentiation in nodule bacteroids protected from osmotic shock by the loftier trehalose levels found in older nodules. Therefore, it is not surprising that a significant number of studies take documented inoculant-strain potency in nodules 5–fifteen years afterwards initial inoculation [112].

Inoculant strains do not e'er persist. Typical is a report by Brockwell et al. [meet reference 108] in which 19 strains of R. leguminosarum bv trifolii were used separately to inoculate subterranean clover in three soils having different numbers of indigenous clover rhizobia. At Murrumbateman where the soil was essentially free of indigenous rhizobia, about inoculant strains produced essentially 100% of the nodules formed in the outset year. In the 2nd year all the same the fraction of nodules produced by the inoculant strains ranged from 19 to 94%. At the Deniliquin B site, where the population of indigenous rhizobia was higher, simply 4 of the strains produced more than 50% of the nodules formed in the second year, and ii strains produced none.

Differences in inoculant-strain contribution to nodule formation over time are unremarkably attributed to strain variation in bacteroid viability, or to differences in strain persistence and competitiveness in soil. Rhizobia are generally considered splendid soil saprophytes and able to persist in soil for quite long periods in the absenteeism of a suitable host [113]. This power has been described every bit saprophytic competence [114], but what determines strain persistence in soil is however poorly defined. Marked strain-to-strain and species variation is clear. 2nd-year nodulation differences at Murrumbatemen were referred to to a higher place. Chatel et al. [114] found low persistence of R. leguminosarum by trifolii in hot/dry sandy soils from Western Australia, only found populations of Bradyrhizobium spp dramatically superior in persistence under serradella. Maurice et al. [115] take noted modify in the physiological land and infective ability of B. japonicum inoculants stored for long periods in liquid civilisation. Can like changes occur in soil after long separation from their host?

An attractive hypothesis is that rhizobial persistence is afflicted by the ability to utilise mutual soil effluvious and hydroaromatic compounds. Parke and Omstom [116] establish meaning differences among the rhizobia in the utilization of these compounds, and besides noted that the enzymes for protocatechuate metabolism were constituitive in Bradyrhizobium spp just inducible in fast-growing rhizobia [117]. Species of rhizobia also differed in chemotaxis toward selected aromatic and hydroaromatic compounds [118]. Unfortunately, Rynne et al. [119] could demonstrate no correlation between catabolic ability and strain persistence. The possibility that unusual compounds exuded by the legume could create rhizosphere weather condition favoring particular rhizobia, first suggested by van Egeraat in 1975, has found favor once again in recent years. Opines [120] and mimosine [121] take been suggested every bit candidate molecules, but many other substances could take similar furnishings. These could include elementary inorganic molecules such as phosphate [122]. Improve methodologies and more detailed studies of rhizosphere community genetics are needed.

Howieson and colleagues developed a cross-row technique used in the selection of strains able to persist and colonize soils under unfavorable ecology conditions (123]. In this procedure, inoculated seeds are planted in rows two g apart, and immune to grow for varying periods of fourth dimension. Uninoculated and surface-sterilized seed of the same species is so planted at 90° to the original row and at distances up to one m from it. After 10–12 weeks plants from the cross rows are harvested, and their nodulation patterns with distance from the initial line of inoculation determined.

When rhizobia are uniformly distributed throughout the soil, competition for nodule occupancy depends on the numbers of each rhizobiwn present and their competitive power with the host cultivar used. This has been modeled both by Ireland and Vincent [124] and past Amarger and Lobreau [125]. Many competition studies have been undertaken, the methods used to evaluate strain differences including serology [92,126], intrinsic or high-level antibiotic resistance [127], ineffective rhizobial marker strains [128], macroscopically distinguishable nodules [129] and lac- or gus- marked strains [130]. Where antibody-resistant mutants are utilized, adequate evaluation of parallel changes in symbiotic performance are essential [131]. Speed of nodulation, corrnnonly assayed using a root-tip mark procedure modified from that of Bhuvaneswari et al. [132], has besides been effective in identifying competitive strains [133]. Lupwayi et al. [134] compared 33 pairs of strains in competition experiments, noting that strains that were faster to nodulate were too more competitive in 10 of xv comparisons. However, when at that place was no divergence betwixt strains in speed of nodulation, only 2 of 18 pairs showed like competitive abilities. From the various speed-of-infection studies undertaken, it appears that rhizobia are not competing directly with each other, only rather attempting to complete a series of interactions with their host during a relatively narrow window of opportunity [135]. Strains able to consummate these interactions volition announced competitive; those that do not will appear to be weak competitors.

As evident from the preference in nodulation data already cited, host cultivar tin can have a marked influence on nodule occupancy. Early studies showed specificity in nodule formation for peas and soybean in the unlike areas of production of these crops [136]. Host x strain interaction is probable to become more evident with the greater apply of molecular methodologies for isolate differentiation. Thus Bernal and Graham [137] noted major differences in the rhizobia recovered when local or introduced cultivars of Phaseolus vulgaris were used. as trap hosts, while Mpepereki et al. [56] and Abaidoo et al. [138] found variation in the rhizobia associated with promiscuously nodulating soybean cultivars in Africa. Other traits likely to be of import in strain competitiveness include historic period of the rhizobia, lysogenic or antibiotic interaction between the strains nowadays [139] and ecology weather (see below).

When seed-applied inoculant rhizobia are introduced into a soil that contains indigenous organisms, the seed-applied organisms form a significant proportion of nodules in the crown region of their host, near where they were placed, but few nodules exterior that region [140]. This is not a competition problem, simply rather one of limited strain mobility and inoculant dilution throughout the root arrangement. It has been suggested that where the indigenous soil rhizobia exceed ten–100 cells 1000−fifty soil, inoculation will not do good the host [106,141]. While this is commonly true, few of the studies on which the asswnption is based used high-dominance inocu1ants or repeated inoculation over years. In contrast, Dunigan et al. [142] establish average recovery of the inoculant strain to increase from less than ten to almost 50% following three years of inoculation. Similar data were reported past Brutti et al. [143].

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Rice in Saline Soils: Physiology, Biochemistry, Genetics, and Management

Mubshar Hussain , ... Ahmad Nawaz , in Advances in Agronomy, 2018

4.5 Plant Growth-Promoting Rhizobacteria

The use of plant growth-promoting rhizobacteria (PGPR) is an acceptable arroyo for reducing the effect of stress-induced ethylene on plants. Seed inoculation with PGPR has the potential to promote rice performance under salinity stress by lowering the ethylene production and improving the growth, antioxidant potential, photosynthesis, and the uptake of minerals such equally Northward, P, K, and Ca ( Bal et al., 2013; Nautiyal et al., 2013; Rangarajan et al., 2003; Sapsirisopa et al., 2009; Sen and Chandrasekhar, 2015).

Seed inoculation with PGPR strains having i-aminocyclopropane-1-carboxylate (ACC) deaminase activity, selected from rhizosphere of rice plants grown in coastal saline soils, reduced the ethylene production and consequently improved the germination, shoot/root growth, and the chlorophyll content of rice plants compared with uninoculated control under salinity stress (Bal et al., 2013). Sen and Chandrasekhar (2014) used two Pseudomonas strains (PF1 and TDK1) for seed inoculation of ii rice genotypes, ADT43 and IR50, grown nether 100   mM NaCl. Common salt stress decreased the root development and acquired stunted growth, and the leaves tips turned white. However, seed handling with PGPR improved the institute height, root length, and dry weight of shoots and roots of both genotypes, and Pseudomonas strain TDK1 was plant better, nether table salt stress. In another study, activities of antioxidant enzymes, i.e., POX, CAT, and NR, were elevated to induce the common salt tolerance in rice genotypes treated with establish PGPR strains PF1 and TDK1 under table salt stress (Sen and Chandrasekhar, 2015). Among all combinations, rice genotype ADT43 treated with TDK1 performed better with more antioxidant activities. Moreover, the phytoremediation via root treatment with PGPR in rice seedlings lowered the negative impacts of salinity stress at afterward crop growth stage and thus improved the ingather yield. Too, the NR activity was inhibited under salt stress; however, the seed treatment with PGPR compensated the NR inhibition to some extent in both rice genotypes under common salt stress (Sen and Chandrasekhar, 2015).

Endophytic bacteria and Rhizobia producing poly-β-hydroxybutyrate (PHB) and glycogen are improve able to survive and reproduce in saline environment and thus can improve soil fertility and the yield of crops. Co-ordinate to Ali et al. (2014), endophytic bacterial strains Enterobacter aerogenes, ET.101 and Enterobacter gergoviae, ET.111 producing more PHB and glycogen improved the growth, grain yield, and yard-grain weight of rice and saved 50% of the fertilizer Northward. These bacterial strains also significantly improved the soil pH, organic matter, and N/P/K contents of the soil (Ali et al., 2014). In another study, Kannan et al. (2014) isolated 16 endophytic bacterial strains from the sodicity-tolerant polyembryonic mango root stock and simply the four strains were found beneficial for rice growth under saline sodic environment.

Some controversial results about the use of bacteria for rice product in saline conditions are also reported. Nakbanpote et al. (2014) isolated bacterial strains PDMCd0501, PDMCd2007, and PDMZnCd2003 from zinc (Zn)/cadmium (Cd)-contaminated soil and classified them as salt-tolerant bacteria due to their IAA production, nitrogen fixation, and phosphate solubilization potential under viii% (w/v) NaCl stress. Biochemical test and 16SrDNA sequencing declared PDMCd2007 and PDMCd0501 as Serratia sp. and PDMZnCd2003 as Pseudomonas sp. Salinity stress (four–sixteen dS   g−   one) impaired the formation and seedlings growth of rice; however, inoculation with Pseudomonas sp. PDMZnCd2003 decreased the rice growth than uninoculated plants. These controversial effects might be due to a high IAA production or pathogenicity of bacterium to rice seedlings (Nakbanpote et al., 2014) which needs further investigation.

In summary, use of the PGPR in rice under saline weather condition can improve phytohormone production and photosynthesis through osmoregulation which improve the nutrient and water uptake and finally the growth. Therefore, inoculation of seed with PGPR is a amend option considering it reduces the production costs and the ecology hazards.

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Molecular basis of found-microbe interaction in remediating organic pollutants

Mrinalini Prasad , ... Rajiv Ranjan , in Handbook of Bioremediation, 2021

1.3 Factors affecting institute microbe interaction

The human relationship between plants and microbes depends upon various factors like bacterial genetic diversity, climatic condition, and soil composition. Bioaugmentation is a procedure in which related leaner and its office are studied. Nevertheless, biotic and abiotic factors affect the functioning of both associations. In this regards, two methods are discussed:

a.

Inoculation: This method is used for the survival of a microorganism and its remediation capacity. Inoculation method affects rhizosphere, soil, colonization, and plant (Afzal, 2010; Afzal et al., 2012, 2013). Basically 4 methods of inoculation are reported (Weyens et al., 2009a, b):

i.

Soil inoculation—Distribution of bacterial liquid culture on the soil surface using irrigation h2o.

two.

Seed inoculation—Germination of seed coat with peat-based slurry in a sugar solution.

iii.

Foliar inoculation—Spraying of liquid bacteria civilization on the surface of soil or plant.

four.

Rhizosphere inoculation—Supply of bacterial culture directly into the rhizosphere past injection or dripping.

Ryegrass was planted with Burkholderia phytofirmans PsJN through unlike inoculation methods in hydrocarbon-contaminated soil (Afzal et al., 2013; Kang, 2014); soil inoculation showed the best upshot in establish growth and phytoremediation. Pantoea sp. grouped with Pseudomonas sp. also showed highest results with soil inoculation (Afzal, 2010). In maize and spinach plants, root or seed inoculation are done to increment the bioavailability of metals to plants (Ali et al., 2013a, b; Ahmad et al., 2016). In some other analysis, a combination of different inoculations was applied against Cd, Pb, and Zn in the tobacco plant, and soil inoculation was found to be the best method (Alvarez et al., 2015). Less literature is bachelor for the inoculation methods and which i is the best way of inoculation.

b.

Colonization of root by bacteria: The combination of institute and microbes are very specific; the plant releases flavonoids for specific microbes, whereas microbes secrete Nod factor to recognize their host plants. The chemical distribution betwixt the plant-microbes are a mutual connection whereby plants supply a carbon source in form of root exudates and microbes provide plant growth-promoting rhizobacteria (PGPR) to back up establish growth (Bais et al., 2008). Benign leaner have the chapters to degrade metallic contaminants, and colonization of roots better the remediation of the rhizosphere (Shukla et al., 2011). P. putida strain PCL1444 was found to be 100-fold more efficient compared with Pseudomonas fluorescens strain WCS365 for the remediation of naphthalene soil in Lolium multiflorum cv. Barmultra plant (Germaine et al., 2009). Even so, plants show more seed germination and transpiration rate by inoculated condition compared with uninoculated controlled plants. Maize plants observed more than growth in Cd-contaminated soils by the inoculation of Klebsiella and Enterobacter strains CIK-518 and CIK-521R, respectively. Also, sunflower showed corking uptake of As from the soil with the help of Alcaligenes sp. strain Dhal-Fifty inoculation (Cavalca et al., 2013). Colonization of the root is the best tool for screening capable microbe strains that support phytoremediation.

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1000-long bean

A. Suma , ... A. Ajinkya , in The Beans and the Peas, 2021

8.6 Organic tillage

Yard-long bean tillage adopting organic package of practices or reduced amount of chemicals is an appreciated approach in the current scenario. Selection of suitable variety, flavor, crop rotation, and availability of organic manures like farmyard manure, compost, green manure, and biopesticide formulations must be ensured. As per the organic parcel of practice recommendations released by KAU (2009) , Bhagyalakshmy, Pusa Barsathi, Pusa Komal, Kairali, Anaswara, Varun, Kanakamony, Arka Garima, Sharika, Malika, Vyjayanthi, Lola, and Vellayani Jyothika are suitable varieties. Seed inoculation and seed pelleting with lime and Rhizobium are recommended for acidic soils. Ordinary agricultural lime and hydrated lime are non recommended. Rhizobium inoculum @ 250 –375   g/ha is recommended for seed treatment. Starch solution @ 2.l% concentration tin be used to ensure better stickiness of the inoculant with the seed. Inoculated seed should exist dried under shade over a clean paper or gunny bag followed past firsthand sowing of hardened seed. In addition, any of the post-obit combinations viz., FYM/cowdung @ two   –t/ha + rock phosphate @ 100   kg/ha or compost @ four   t/ha + rock phosphate @ 70   kg/ha or vermicompost @ 2   t/ha + rock phosphate @ 110   kg/ha or greenleaf @ 3.5   t/ha + rock phosphate @ 100   kg/ha or poultry manure @ 1.5   t/ha + rock phosphate @ 50   kg/ha tin exist applied. Biofertilizers like arbuscular mycorrhizal fungi/phosphorus solubilizing microorganisms @ one   thou per institute at the fourth dimension of sowing increases the P availability. Foliar awarding of growth promoters like panchagavyam or vermiwash at fortnightly intervals increases marketable yield.

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Microbial bioformulations: Revisiting role in sustainable agriculture

Sharon Nagpal , ... Kailash Chand Kumawat , in Biofertilizers, 2021

25.nine Techniques for inoculation

Formulated biofertilizer can exist applied every bit seed inoculation with powder formulations, dry biofertilizers mixed with the seeds, mixing h2o and peat powder, suspending the biofertilizer in water along with seeds, seed pelleting, biofertilizer with adhesive and material such as lime, peat suspension in water seed inoculation, soil application, and seedling root dip ( Mahanty et al., 2016). Each method has advantages and disadvantages, depending on the requirements for specific inoculation, the type of seed, and the corporeality of inoculant. Techniques should exist such that they stimulate growth and proliferation even nether extreme temperature, drought, fungicides, and herbicides.

25.9.1 Inoculation with seed

Inoculant handling with seeds is an effective and economical approach for field awarding (Sethi et al., 2014). Seeds are mixed with slurry, dried in shade, and sown within a day. Blanket in example of liquid biofertilizers tin be done in plastic bag. It provides adequate amount of desired biofertilizer on seed ensuring better results (Chen, 2006). Rhizobium, Azotobacter, and Azospirillum or phosphorus-solubilizing bacteria are all applied with seed for delivery in field. The inoculant is mixed with seeds either past hand, rotating drums that are cheap to operate, large dough or cement mixers, mechanical tumbling machines (Schulz and Thelen, 2008), or automated seeders. Coating of seeds with calcium carbonate (limestone) and additional agglutinative layer is necessary to neutralize soil'due south acidic nature (Bashan et al., 2014 ). Disadvantages associated with seed inoculation include seed coat lifting out of the soil, desiccation, and loss of viability of the inoculants. Owing to small size of seeds, only limited amount of inoculant can be applied leading to the loss of efficiency. Dislodging of inoculants by the sowing machinery and damage to fragile seed coats may occur. Antibacterial compounds released from the seeds of some crops may inhibit the inoculants. Application of fungicides and insecticides may impairment the applied inoculants ( Bashan et al., 2014).

25.9.2 Inoculation in soil

Soil inoculation is useful when a large number of viable bacteria are to exist introduced. High load of microbes in soil inoculation removes many constraints associated with other related techniques. Granular inoculants ranging from 0.5 to i.5   mm are kept in the seedbed with the seed at time of sowing (Mahanty et al., 2016 ). Soil inoculation minimizes the risk of washing away of the desired inoculants through the seeding mechanism. Small seeds are better for soil inoculation equally higher loads of inoculants can be applied on them. Larger quantities of required inoculants along with specialized equipment are prerequisite for soil inoculation. Soil inoculation is rather expensive in terms of transport and storage area over seed inoculation. Various biofertilizers, viz., Rhizobium in legumes and Azotobacter in fruit/agroforestry plants are commercialized as soil applicants (Bashan et al., 2014). Equipment, size and fragility of seed coat, fungicide awarding, and inoculant affordability to farmers determine the usage of a detail inoculation method (Deaker et al., 2004).

25.ix.three Inoculation with seedling roots

Infecting the roots of the crop is another important technique of inoculation. Diverse procedures such as aeroponics (Hung and Sylvia, 1988), hydroponics (Dehne and Baekhaus, 1986), and Ri t-DNA transformed roots (Diop and Piche, 1990) are used for root inoculation. Roots infected with mycelium and spores tin can colonize the host within i or ii   days of inoculation. The inocula which practise not class spores should be applied within a week. In vitro propagation of many arbuscular mycorrhizal fungi on roots of several plants has been demonstrated (Napamornbodi et al., 1988). The process is hard, expensive, and usually undertaken for plantation crops (cereals, vegetables, fruits, copse, sugarcane, cotton wool, grapes, banana, and tobacco). In this procedure, roots of seedlings are dipped in a biofertilizer suspension made in water for ample amount of time which varies from xx to thirty   min in vegetables and viii to 12   h in paddy (Thomas and Singh, 2019). Infected roots serve every bit a source of nutrients for diverse range of saprophytes and parasites. Another limitation includes requirement of heavy inoculum loads and less survival time of inoculants on roots.

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The Potential of Agro-Ecological Backdrop in Fulfilling the Hope of Organic Farming

Bita Naseri , in Organic Farming, 2019

12.15 Rhizobial Symbiosis

In the greenhouse, liming of acidic soils decreased FRR (Tu, 1992) and improved bean nodulation and yield (Buerkert et al., 1990). In Republic of india, Hassan Dar et al. (1997) reported the reduction of FRR past 34.three% and improvement of plant biomass due to the inoculation of FRR-afflicted beans with Rhizobium leguminosarum. Based on the findings of Estevez de Jensen et al. (2004) , seed inoculations with R. leguminosarum affected FRR and bean yield, depending on the experimental site and study yr. In the edible bean–RRR pathosystem, R. leguminosarum inhibited R. solani hyphal growth and suppressed the affliction (Blum et al., 1989; Ehteshamul-Haque and Ghaffar, 1993; ÖzkoC and Delıvelı, 2001). Ansari (2010) reported effective CRR control by applying Zn forth with Bradyrhizobium japonicum and T. viride. Hassan Dar et al. (1997) attributed variations in the bean–FRR–Rhizobium interaction to differences in symbiont bacteria, host found, pathogen, and soil characteristics across unlike geographical areas. Supporting previous small-scale-scale findings, the natural presence of rhizobial nodulation on bean roots restricted the development of FRR-RRR-CRR-FW epidemics and improved productivity under highly dissimilar microbial, crop, and environmental conditions on a regional basis (Naseri, 2013a, 2014a; Naseri and Moradi, 2014; Naseri and Mousavi, 2014). Kalantari et al. (2018) found that Rhizobium sp. was the most prevalent bacterial symbiont in the master bean-growing region in Zanjan. However, the presence of loftier nodulation in only 12.3% of the commercial bean fields may refer to the office of iron deficiency, which is problematic in calcareous soils of Zanjan (Naseri 2013a) in inhibiting legume–rhizobia symbiosis and plant growth (Slatni et al., 2008). From the viewpoint of organic production, our macro-scale approaches advise edible bean growers to reinforce rhizobial nodulation for sustainable tillage (Naseri and Hemmati 2017).

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Seed biopriming a novel method to control seed borne diseases of crops

Monika Sood , ... Ruby Rawal , in Biocontrol Agents and Secondary Metabolites, 2021

eight.3.1.1 Plant growth-promoting rhizobacteria

Kloepper (1978) for the commencement time make use of the word establish growth-promoting rhizobacteria (PGPR) describing them as bacteria which are intimately associated with rhizosphere. PGPR inoculation has augmented diverse crop produces in normal and stressful circumstances. Seed priming through PGPR, i.e., soaking the seeds for a precalculated period in liquid bacterial suspension, initiate the physiological processes inside the seed while radicle and plumule emergence is prohibited till the seed is propagated (Anitha et al., 2013). This spread of adversary PGPR inside the seeds is 10-fold than infecting pathogens which enables the establish to survive those pathogens mounting the use of biopriming for the purpose of biocontrol also (Callan et al., 1990 ). Seed inoculation involves the use of carrier material for better transportation and application, use of adhesives to ensure the sticking of leaner to the seeds and sometimes other materials avoiding desiccation of the inoculum ( Elegba et al., 1984). Peat-based inoculants are most common and extensively used since the discovery of rhizobium for leguminous crops (Walker et al., 2004).

Most favored and commonly used method of inoculation includes application of adhesive agents on the seeds followed past inoculum spreading under shade (Vincent et al., 1962). Amongst the adhesive agents, most used are Arabic gum, saccharide solution, methylcellulose, polyvinylpyrrolidone, caseinate salts and polyvinyl acetate (Deaker et al., 2004). Reddy (2012) explained biopriming more in biocontrol aspect equally an application of beneficial bacterial inoculum to the seeds and their hydration protect these seeds confronting several diseases. PGPR keep on multiplying in the seed and proliferate in the spermosphere fifty-fifty earlier sowing (Taylor and Harman, 1990). Biopriming treatment is potentially able to promote quick and even formation too as better constitute growth (Moeinzadeh et al., 2010). Biopriming with rhizospheric bacteria has been reported in crops such every bit carrot (Jensen et al., 2001), sweet corn (Callan et al., 1990, 1991), and tomato (Warren and Bennett, 1999; Harman et al., 1989). In the instance of efficacy and survival of biological agents, priming has been reported beneficial and enhance the plant growth and yield (Callan et al., 1990, 1991; Warren and Bennett, 1999; Harman et al., 1989). Germination and enhanced bulb institution are obtained through seed priming with PGPR (Anitha et al., 2013). Bio-osmopriming tin significantly enhance the uniformity of the germination and plant growth traits when associated with bacterial coating (Bennett, 1998).

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Halophilic microbial bioformulations for bioremediation of salt-affected soils

Sanjay Arora , ... D. Sahni , in Biofertilizers, 2021

22.12 Multilocation awarding of halophilic bioformulations

Multilocational testing and validation of the bioremediation potential of liquid bioformulations were conducted during 2014–17 in eight districts of Upwards to ascertain the efficacy of halophilic plant growth-promoting strains of North-fixers and P-solubilizers on crop growth and yield on sodic soils.

Nether sodic and saline-sodic soils, bioformulation has been tested at farm, validated at dissimilar farmers' fields in more than than six districts of salt-affected areas. The bulb dip or seed inoculation with the bioformulation resulted in enhanced crop yields, direction of soil health, and stress regulation. These liquid bioformulations are very beneficial for enhancing production of cereal crops, mainly rice and wheat also equally vegetable crops. These tin be hands used as seed treatment, seedling dip, and soil application with FYM or organic manure. A 100  mL packed bottle is sufficient for treating seeds of one   acre land or root dip. It has been establish to be very effective in sodic soil and multilocation testing of these bioformulations was washed in diverse sodic soils of Indo-Gangetic plains (Arora and Singh, 2017). At that place was increase in rice and wheat yield by 11.5%–14% nether salt stress conditions in Indo-Gangetic plains (Fig. 22.2). The average B:C ratio enhanced from 2.10 to two.31 in rice and enhanced from 2.26 to two.59 in wheat with the use of bioformulations. The formulation was constitute to be suited for soils having a pH of between 7.5 and ix.8. Application of these bioformulations keeps the soils biologically active and helps in maintenance of overall soil wellness. During the rabi and kharif seasons of 2017 and 2018 in, these bioformulations take been adopted by farmers covered approximately 300 and 338   ha of sodic lands in various districts (Lucknow, Raebareli, Unnao, Sitapur, Hardoi, Sultanpur, Kaushambi, Pratapgarh, Agra, and Etawah) of UP in dissimilar crops (rice, wheat, mustard, brinjal, cauliflower, field pea, tomato, and sugarcane). Considering the potential of this technology, it was made available commercially through the ICAR-Agriinnovate India Ltd.

Fig. 22.2

Fig. 22.2. Average bear upon of liquid bioformulations on rice and wheat yield under common salt stress (confined shows standard fault).

In a field experiment at the farmers' fields in Unnao commune, halophilic bioformulations, Halo-Azo and Halo-PSB were co-inoculated; it was observed that rice germination pct, plant establishment percent, number of effective tillers per hill, number of grains per panicle, exam weight, and grain yield were recorded to exist higher past 1.4%, one.5%, ane.75%, 2.21%, 1.i%, and 3.6%, respectively, compared to uninoculated control. The increment in grain yield was 8.five%, 12.5%, and 18.0% over control, past the inoculation with bioformulations, viz., Halo-Azo, Halo-PSB, and Halo-Azo   +   Halo-PSB, respectively (Sahay et al., 2018). Inoculation of bioformulation besides increased the straw yield of crop by upwards to 11.half-dozen% as compared to command.

Similarly, in wheat, both bioformulations significantly increased the unlike growth parameters and yield of the crop as compared to control. The increase in wheat grain yield was thirteen.06% higher with the inoculation of both bioformulations as compared to 7.7% and 9.three% increase with solo inoculation of Halo-Azo and Halo-PSB over control. It has been inferred from the experiment that exploitation of halophilic bioformulations as biofertilizers with salt-tolerant varieties of rice and wheat has enormous potential in the utilization of unfertile sodic country for nutrient security, ecology wellness, and economic welfare of farmers.

Effect of integrated use of liquid bioformulations Halo-Azo, Halo-PSB, and Halo-Zinc with 75% of recommended dose of NPK showed a 6.vii% increase in grain yield of salt-tolerant short-elapsing variety of paddy grown on sodic soil of pH   nine.6 over 100% recommended NPK and zinc sulfate (Singh and Mishra, 2018). At different sodicity levels, it was observed that there was significantly at par yield of paddy (multifariousness CSR46) at pH   9.iv when 75% recommended NPK along with Halo-Azo, Halo-PSB, and Halo-Zinc were inoculated and when 100% recommended NPK with zinc sulfate was applied (Table 22.two) (Singh and Mishra, 2019). In coastal saline soils, the highest grain yield of v.12   t/ha of rice diversity "Sumati" was reported with combined application of liquid bioformulations Halo-Azo and Halo-PSB compared to a grain yield of iv.69   t/ha in uninoculated control, indicating yield enhancement of 9.1% (Sarangi and Lama, 2018).

Table 22.2. Consequence of bioformulations on functioning of paddy in sodic soil.

Sodic soil 100% RDF   +   25   kg ZnSO4  ha−   1 75% RDF   +   Halo-Azo   +   Halo-PSB 75% RDF   +   Halo-Azo   +   Halo-PSB   +   Halo-Zinc
pH   =   8.viii 56.5 52.6 55.4
pH   =   9.0 52.2 51.ix 54.1
pH   =   nine.2 44.8 41.ix 42.3
pH   =   9.4 39.7 38.six 40.vi
Mean 48.three 46.3 48.one
CD (5%) 1.46

Liquid bioformulations were used in different crops on farmers' field at Hasanganj, Auras, Rashidpur in Unnao district on sodic soil (pH   viii.6–9.four). Information technology was observed that crop yield was enhanced in the range of eight.8%–26.3%. Field pea seed inoculation with liquid bioformulations Halo-Azo   +   Halo-PSB   +   Halo-Zinc resulted in an increment of ix.5%–26.3% equally compared to noninoculation (Table 22.iii). Similarly, seedling dip of onion with liquid bioformulations Halo-Azo   +   Halo-PSB   +   Halo-Zinc was institute to enhance the yield past upwards to 73.seven   q ha−1 compared to a maximum of 65.3   q ha−1 where no inoculation was done. Mustard seed treatment with liquid bioformulations Halo-Azo   +   Halo-PSB   +   Halo-Zinc, resulted in an increase of yield by 11.4%–18.7% compared to noninoculated control.

Table 22.3. Performance of different crops at farmers fields in sodic soils (soil pH   8.half dozen–ix.4).

Crop Yield without bioformulations (q ha−1) Yield with bioformulations (Halo-Azo   +   Halo-PSB   +   Halo-Zn) (q ha−1) % Yield increase
Field pea (number of sampling site, northward  =   xv) 19.two–21.vii 22.3–25.four nine.5–26.3
Onion (n  =   7) 62.four–65.3 68.ii–73.7 8.8–12.3
Mustard (n  =   three) 16.4–18.ane 18.8–xix.five 11.4–18.7

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Friends in depression places: Soil derived microbial inoculants for biostimulation and biocontrol in crop product

David Johnston-Monje , ... Ana Cristina Bolaños , in Microbiome Stimulants for Crops, 2021

2.4.1 Aiding in found nutrition

One of the principle limitations in ingather productivity is access to nutrients in the soil, principally N and P, only plants have developed associations with microbes that aid them cope (Johnston-Monje et al., 2019). Diazotrophic leaner in the rhizosphere are able to set up atmospheric N into forms available for absorption by the root and have been well reviewed (Kennedy, Choudhury, & Kecskés, 2004; Rosenblueth et al., 2018). For example, Azotobacter chroococcum RK49 isolated in nitrogen free media from soil in Northern Anatolia, Turkey (considered the heart of origin of wheat) was able to increment spring wheat N content and grain yield by 84% compared to uninoculated controls (Kızılkaya, 2008). N-fixing Azospirrillum spp. isolated from rhizospheres of various plant species are also a very common inoculant for increasing soil N and grain yield. After seed inoculation of nine different strains of Azospirillum isolated from maize roots in Curitiba, Parana, Brazil, field-grown maize and wheat showed increases in macronutrient levels and yield increases of 24%–30% and 13%–eighteen%, respectively (Hungria et al., 2010).

Rhizosphere microbes can also aid in mineralizing and solubilizing biounavailable nutrients into forms that plant roots can absorb. Soil P is oftentimes biounavailable in organic molecules that plants can't absorb, yet, a large number of soil microbes possess the ability to solubilize it (Alori, Glick, & Babalola, 2017). Probably the most famous inoculant for P solubilization is JumpStart which is sold by Novozymes. This inoculant is based on the mucus Penicillium bilaiae which was isolated from southern Alberta (Canada) prairie soils in 1983 (Kucey, 1983). The fungal inoculant is applied to corn, canola, wheat, or legume seeds before planting, and grows along plant roots, enhancing branching and hair formation while enzymatically releasing organically leap P in the rhizosphere (Leggett et al., 2007).

Soil microbes may help in plant diet through other unknown or recently discovered ways. For instance, intercropping peanut with cassava has been shown to increase the rhizosphere populations of DA101, Pilimelia, and Ramlibacter which coincide with elevated yield and nearly 20-fold increases in bioavailable soil North, P, K, merely other than nitrogen fixation from rhizobia in the peanuts, it is not known what mechanisms might be involved (Tang et al., 2020). A recently discovered biological process termed the "rhizophagy cycle" postulates that roots "phagocytize" soil-dwelling endophytes that are charged up with nutrients, and equally they passage through the root, they are tuckered of their nutrients and digested by the plant (Paungfoo-Lonhienne et al., 2010; White et al., 2018).

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