Microorganisms are considered a genetic resource with great potential for achieving sustainable development of agricultural areas. The objective of this research was to determine the effect of ...microorganism application forms on the production of biomass, gas exchange, and nutrient content in upland rice. The experiment was conducted under greenhouse conditions in a completely randomized design in a factorial 7 × 3 + 1, with four replications. The treatments consisted of combining seven microorganisms with three application forms (microbiolized seed; microbiolized seed + soil drenched with a microorganism suspension at 7 and 15 days after sowing (DAS); and microbiolized seed + plant sprayed with a microorganism suspension at 7 and 15 DAS) and a control (water). Treatments with
Serratia
sp. (BRM32114),
Bacillus
sp. (BRM32110 and BRM32109), and
Trichoderma asperellum
pool provided, on average, the highest photosynthetic rate values and dry matter biomass of rice shoots. Plants treated with
Burkolderia
sp. (BRM32113),
Serratia
sp. (BRM32114), and
Pseudomonas
sp. (BRM32111 and BRM32112) led to the greatest nutrient uptake by rice shoots.
Serratia
sp. (BRM 32114) was the most effective for promoting an increase in the photosynthetic rate, and for the greatest accumulation of nutrients and dry matter at 84 DAS, in rice shoots, which differed from the control treatment. The use of microorganisms can bring numerous benefits of rice, such as improving physiological characteristics, nutrient uptake, biomass production, and grain yield.
Leaf blast is the main rice disease in the world causing significant losses in productivity. Blast integrate management (BIM) requires the use of genetic resistance, cultural practices, and chemical ...control, although for sustainable BIM, the insertion of biological agents may be the fourth component for. The objective of this work was to test three formulations of
Burkholderia pyrrocinia
(BRM32113) previously selected and to verify the effectiveness in resistance induction and blast control in rice. Two experiments were carried out, in a completely randomized design with three replications, in the greenhouse (E1 and E2). E1 aimed to select the best treatment for suppressing leaf blast severity and activating plant defense mechanisms. It was composed of 8 treatments: (1) formulated 11+
B. pyrrocina
×
Magnaporthe oryzae
; (2) formulated 17+
B. pyrrocina
×
M. oryzae
; (3) formulated 32+
B. pyrrocina
×
M. oryzae
; (4) formulated 11 ×
M. oryzae
; (5)
B. pyrrocinia
17 ×
M. oryzae
; (6) formulated 32 ×
M. oryzae
; (7)
B. pyrrocina
×
M. oryzae
; (8)
M. oryzae
; (9) control (water). E2 aimed to investigate the effect of the best treatments, for the promotion of plant growth and suppression of leaf blast by calculating AUDPC. It was composed of 6 treatments: (1) formulated 11+
B. pyrrocina
×
M. oryzae
; (2) formulated 32+
B. pyrrocina
×
M. oryzae
; (3) formulated 11 ×
M. oryzae
; (4) formulated 32 ×
M. oryzae
; (5)
B. pyrrocina
×
M. oryzae
; (6) water. And after, we did two assays aimed to localize this biological agent after application at seed, soil, and rice plant. In E1, formulated 11+
B. pyrrocinia
and 32+ formulated and
B. pyrrocina
were the best, suppressing leaf blast by up to 97% and providing the significant increase of the enzymes β-1,3-glucanase, chitinase, phenylalanine ammonia lyase, lipoxygenase, and salicylic acid at 24 h and 48 h after inoculation with
M. oryzae
. In E2, treatments formulated 11+
B. pyrrocinia
, formulated 32+
B. pyrrocinia
, and
B. pyrrocina
provided more significant increases in growth promotion and reduced area under disease progress curve.
B. pyrrocinia
was detected in the rice plant for 18 days, predominantly in the root system (internal and external). The use of
B. pyrrocinia
formulations based on sugarcane molasses and glycerol can be an essential strategy for sustainable management. Although all the benefits come from these sustainable formulations, the adoption by commercial biological segment depends on an established formulation process. It seems that all the results showed here by this research will be readily assimilated by startups of the organic segment.
An alternative method to control rice blast (
Magnaporthe oryzae
) is to include biological agent in the disease management strategy. The objective of this study was to assess the leaf ...blast-suppressing effects of rice phylloplane fungi. One
Cladosporium
sp. phylloplane fungus was shown to possess biocontrolling traits based on its morphological characteristics and an analysis of its 18S ribosomal DNA. Experiments aimed at determining the optimal time to apply the bioagent and the mechanisms involved in its rice blast-suppressing activities were performed under controlled greenhouse conditions. We used foliar spraying to apply the
Cladosporium
sp. 48 h prior to applying the pathogen, and we found that this increased the enzymatic activity. Furthermore, in vitro tests performed using isolate C24 showed that it possessed the ability to secrete endoxylanases and endoglucanases. When
Cladosporium
sp. was applied either prior to or simultaneous with the pathogen, we observed a significant increase in defence enzyme activity, and rice blast was suppressed by 84.0 and 78.6 %, respectively. However, some enzymes showed higher activity at 24 h while others did so at 48 h after the challenge inoculation.
Cladosporium
sp. is a biological agent that is capable of suppressing rice leaf blast by activating biochemical defence mechanisms in rice plants. It is highly adapted to natural field conditions and should be included in further studies aimed at developing strategies to support ecologically sustainable disease management and reduce environmental pollution by the judicious use of fungicidal sprays.
Bioagents and silicon promoting fast early upland rice growth de Sousa, Thatyane Pereira; de Souza, Alan Carlos Alves; de Filippi, Marta Cristina Corsi ...
Environmental science and pollution research international,
02/2018, Letnik:
25, Številka:
4
Journal Article
Recenzirano
Upland rice can overcome major challenges through the insertion of silicate fertilization and the presence of plant growth-promoting microorganisms (PGPMs) during its cultivation, as these factors ...promote an increase in vigor and plant disease resistance. Two consecutive experiments were conducted to evaluate the beneficial effects of silicon fertilization combined with the PGPM,
Pseudomonas fluorensces
,
Burkholderia pyrrocinia
, and a pool of
Trichoderma asperellum
, in upland rice seedlings, cultivar BRS
Primavera
CL: (a) E1, selecting PGPM type and Si doses for rice growth promotion and leaf blast supression, and (b) E2, evaluating physiological characteristics correlated with mechanisms involved in the higher vegetative growth in highlighted treatments from E1. In E1, 2 Si t ha
−1
combined with the application of
T. asperellum
pool or PGPM mixture increased 54% in root dry matter biomass and 35 and 65% in shoot and root lengths, respectively; it also suppressed 99% of rice blast severity. In E2, shoot and root dry matter biomass and length, photosynthetic rate, water use efficiency, total soluble sugar, and chloroplastidic pigments were superior in BRS Primavera CL seedlings treated with 2 Si t ha
−1
and
T. asperellum
pool or PGPM mixture. Higher salicilic and jasmonic acid levels were found in seedlings treated with Si and
T. asperellum
pool, individually. These physiological characteristics may explain, in part, the higher vigor of upland rice seedlings promoted by the synergistic effect between silicate fertilization and beneficial microorganisms.
Effects of beneficial microorganisms on lowland rice development Nascente, Adriano Stephan; de Filippi, Marta Cristina Corsi; Lanna, Anna Cristina ...
Environmental science and pollution research international,
11/2017, Letnik:
24, Številka:
32
Journal Article
Recenzirano
Microorganisms can promote plant growth by increasing phytomass production, nutrient uptake, photosynthesis rates, and grain yield, which can result in higher profits for farmers. However, there is ...limited information available about the physiological characteristics of lowland rice after treatment with beneficial microorganisms in the tropical region. This study aimed to determine the effects of different beneficial microorganisms and various application forms on phytomass production, gas exchange, and nutrient contents in the lowland rice cultivar ‘BRS Catiana’ in a tropical region. The experiment was performed under greenhouse conditions utilizing a completely randomized design and a 7 × 3 + 1 factorial scheme with four replications. The treatments consisted of seven microorganisms, including the rhizobacterial isolates BRM 32113, BRM 32111, BRM 32114, BRM 32112, BRM 32109, and BRM 32110 and
Trichoderma asperellum
pooled isolates UFRA-06, UFRA-09, UFRA-12, and UFRA-52, which were applied using three different methods (microbiolized seed, microbiolized seed + soil drenched with a microorganism suspension at 7 and 15 days after sowing (DAS), and microbiolized seed + plant spraying with a microorganism suspension at 7 and 15 DAS) with a control (water). The use of microorganisms can provide numerous benefits for rice in terms of crop growth and development. The microorganism types and methods of application positively and differentially affected the physiological characteristics evaluated in the experimental lowland rice plants. Notably, the plants treated with the bioagent BRM 32109 on the seeds and on seeds + soil produced plants with the highest dry matter biomass, gas exchange rate, and N, P, Fe, and Mg uptake. Therefore, our findings indicate strong potential for the use of microorganisms in lowland rice cultivation systems in tropical regions. Currently, an additional field experiment is in its second year to validate the beneficial result reported here and the novel input sustainability.
Multifunctional microorganisms (MMs) can have beneficial effects on plants through direct and indirect mechanisms. This study aimed to determine the effect of MMs on shoot and root biomass ...production; gas exchange; content of macronutrients in the shoots, roots and grains; yield components; and grain yield of common bean plants. A completely randomized design with twenty-six treatments and three replications was used under controlled conditions. Treatments consisted of the application of MMs and their combinations in pairs, with the nine rhizobacteria isolates BRM 32109, BRM 32110 and 1301 (Bacillus sp.), BRM 32111 and BRM 32112 (Pseudomonas sp.), BRM 32113 (Burkholderia sp.), BRM 32114 (Serratia sp.), 1381 (Azospirillum sp.) and Ab-V5 (Azospirillum brasilense); an edaphic fungal isolate T-26 (Trichoderma koningiopsis); and a control (without MMs). These MMs were applied at three time points: microbiolization of the seeds, watering the soil seven days after sowing (DAS) and spraying the plants with 21 DAS. In comparison to the control plants, the isolates 1301 and T-26, in addition to the combinations Ab-V5 + T-26, BRM 32114 + BRM 32110 and 1381 + T-26, provided better results, with an increase of 36.5% in the grain yield, a higher accumulation of biomass (78.0%) and a higher content of N, P and K (42.6, 67.8 and 25.7%, respectively) in the shoots of common bean plants. Therefore, the results allow us to infer that the use of MMs is a good strategy for increasing common bean grain yields.
Combining cover crops with multifunctional microorganisms provides significant increments in the grain productivity of soybean and upland rice crops. However, there are still few studies that aimed ...to evaluate the effect of this combination on the productivity of agricultural systems. The objective of this study was to determine the effect of the mix of cover crops and the co-inoculation of multifunctional rhizobacteria on the quality of the soil, yield components, and on the grain yield of soybean and upland rice. The experimental design was in random blocks with 24 treatments in a 6x2x2 factorial scheme. Treatments were the combination of 6 (5 mix of cover crops (mixture of seeds of different cover crops species) and the control (fallow), 2 (upland rice and soybeans), 2 (co-inoculated (inoculation with two microorganisms) or not (no microorganisms), with four replications. Combination of cover crops provided an increase in Ca and Mn levels in the soil, increased activity of soil quality indicator enzymes (phosphatase and arylsulfatase), higher soybean yield, and higher number of upland rice panicles. The co-inoculation with multifunctional rhizobacteria led to an increase in phosphorus levels in the soil, the number of pods per plant, the mass of 100 grains for soybean cultivation, the number of grains per panicle, and productivity of upland rice. Therefore, a mix of cover crops, combined with the co-inoculation with multifunctional rhizobacteria are sustainable agricultural practices that can contribute to the improvement of soil quality and the increase of the productivity of soybean and upland rice crops.
One of the most important events for the success of parasitism is the nematode recognition of chemical signals exuded by the host plant. In response to the establishment of interactions, plants have ...evolved improved defence mechanisms. The present study aimed to identify resistance mechanisms by comparing the biochemical defence response of two chilli pepper (Capsicum spp.) genotypes (Bode roxa A‐resistant and Cambuci‐susceptible) to Meloidogyne enterolobii. The activity of β‐1,3‐glucanase (GLU), peroxidase, chitinase (CHI), phenylalanine ammonia‐lyase and lipoxygenase (LOX) was evaluated in the leaves and the roots at 7, 14, 21, 28 and 35 days after inoculation. There was an increase of GLU and CHI in leaves, and LOX in leaves and roots activities, of the resistant genotype (Bode roxa A). These results allow a better understanding of the defence mechanisms involved in the resistance of Capsicum spp. to M. enterolobii, which is an important step in developing management strategies for this pathosystem.
Rice blast management is heavily reliant on chemical control, and the rise of fungicide resistance is contingent on fitness costs. This study contrasts the responses of 322 blast isolates from ...southern (n = 224) and northern Brazil (n = 98) to fungicides in the Quinone outside inhibitor (QoI), Sterol demethylation inhibitor (DMI), and Melanin biosynthesis inhibitor (MBI) groups, and associated epidemiological traits. Resistance was more prevalent in northern Brazil, where conditions are most conducive to blast. Northern populations displayed higher EC50 for spore germination, faster mycelial growth rates, and higher rates of appressorium formation for fungicides in all chemical groups. Results were most striking for the QoI fungicide azoxystrobin. We examined possible fitness penalties and related in planta competitive abilities associated with the gain of azoxystrobin resistance. QoI-resistant (QoI-R) genotypes, carrying the G143A cytochrome b gene mutation, were found in 90% of the northern isolates. The EC50 values of these QoI-R isolates exceeded 10 μg L−1. However, QoI-R isolates had a reduced number of conidia, longer latent period, reduced infection efficiency and aggressiveness, compared to the sensitive isolates. These impairments were reflected in a decrease of competitive ability in planta in the absence of azoxystrobin. Nevertheless, under continuous fungicide applications, the proportion of resistant and sensitive isolates in mixed cultures in planta remained constant after four generations. The results are valuable for managing strategies as the increase of resistance may hamper the competitive abilities of QoI-R mutants in the absence of the respective active ingredient.
•Fungicide resistance is widespread in rice-derived isolates of P. oryzae from Brazil.•Fungicide resistance and the G143A mutation are more prevalent in northern Brazil.•Fitness penalties are associated with resistance to the QoI azoxystrobin.•Fitness costs of QoI-R isolates resulted in loss of competitiveness in planta.
ABSTRACT Multifunctional microorganisms can contribute significantly to improve plant performance and are innovative technology for sustainable development. Thus, objective of this study was to ...determine the effect of bioagents applied alone or in mix on the performance of upland rice. The experiment was conducted in a greenhouse in a completely randomized design with four replications. The 26 treatments consisted of the rhizobacteria Bacillus sp. (BRM 32109, BRM 32110 and 1301), Azospirillum sp. (1381), Azospirillum brasilense (Ab-V5), Pseudomonas sp. (BRM 32112), Pseudomonas fluorescens (BRM 32111), Burkholderia pyrrocinia (BRM 32113), Serratia sp. (BRM 32114), and a fungal genus formed by a pool of Trichoderma asperellum (T-06, T-09, T-12, and T-52), applied alone or in mix, plus a control treatment without microorganism application. The most effective treatments were the mixes of microorganisms 1301 + Ab-V5 and BRM 32114 + pool of Trichoderma asperellum, as they provided an average increase of 123 and 88% in the number of panicles and 206 and 167% in the grain yield of upland rice plants, respectively. Mixes of 1301 + Ab-V5, BRM 32114 + Trichoderma asperellum pool, BRM 32110 + BRM 32114, BRM 32110 + Ab-V5, 1301 + BRM 32110 and 1381 + Trichoderma asperellum pool also provided better morphophysiological performance in rice plants (photosynthetic rate, carboxylation efficiency, number of tillers, shoot dry biomass and nutrient content in shoot and root). Therefore, the use of multifunctional microorganisms in the management of upland rice was efficient in its ability to provide better development of plants.
RESUMO Microrganismos multifuncionais podem contribuir significativamente para melhorar o desempenho das plantas, sendo tecnologia inovadora quando se visa o desenvolvimento sustentável. Assim, objetivou-se determinar o efeito de microrganismos multifuncionais aplicados isolados ou em mix sobre o desempenho do arroz de terras altas. O experimento foi conduzido em casa de vegetação, em delineamento inteiramente casualizado, com quatro repetições. Os 26 tratamentos consistiram das rizobactérias Bacillus sp. (BRM 32109, BRM 32110 e 1301), Azospirillum sp. (1381), Azospirillum brasilense (Ab-V5), Pseudomonas sp. (BRM 32112), Pseudomonas fluorescens (BRM 32111), Burkholderia pyrrocinia (BRM 32113), Serratia sp. (BRM 32114), e um gênero fúngico formando um pool de Trichoderma asperellum (T-06, T-09, T-12, e T-52), aplicados isoladamente ou em consórcio, mais o tratamento controle, sem aplicação de microrganismos. Os tratamentos mais efetivos foram os mixes de microrganismos 1301 + Ab-V5 e BRM 32114 + pool de Trichoderma asperellum, uma vez que proporcionaram aumento, em média, de 123% e 88% no número de panículas e de 206 e 167% na produtividade de grão do arroz de terras altas, respectivamente. Os consórcios 1301 + Ab-V5, BRM 32114 + pool de Trichoderma asperellum, BRM 32110 + BRM 32114, BRM 32110 + Ab-V5, 1301 + BRM 32110 e 1381 + pool de Trichoderma asperellum, também proporcionaram maior desempenho morfofisiológico nas plantas de arroz (taxa fotossintética, eficiência de carboxilação, número de perfilhos, biomassa seca de parte aérea e teor de nutrientes na parte aérea e raiz das plantas). Portanto, o uso de microrganismos multifuncionais no manejo do arroz de terras altas foi eficiente em sua capacidade de proporcionar maior desenvolvimento das plantas.
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