Inoculation and co-inoculation of Bradyrhizobium japonicum and Azospirillum brasilense in soybean crop with the use of soil bio-activator
Victor Matheus Röske¹*, Vandeir Francisco Guimarães², Tauane Santos Brito², Alexandre Wegner Lerner², Roberto Cecatto Junior², André Silas Lima Silva² and Michele Aline Anklan²
¹C. Vale Cooperativa Agroindustrial, Palotina, Paraná, Brasil.
²Universidade Estadual do Oeste do Paraná, Marechal Candido Rondon, Paraná, Brasil.

Abstract
In view of the high nitrogen availability required by soybean, inoculation with nitrogen fixing bacteria, such as Bradyrhizobium japonicum, is an economically viable option. Moreover, the co-inoculation of these microorganisms with plant growth promoting bacteria, such as Azospirillum brasilense, presents high efficiency compared to the isolated use of these microorganisms. Given the above, the study aimed to determine the effects of applying a soil bio-activator associated with the inoculation of Bradyrhizobium japonicum and Azospirillum brasilense bacteria, on morphometric, physiological and productive variables of soybean crop. The experiment was conducted in the field, in a randomized block design with four replicates. The treatments were: control; seed inoculation with Bradyrhizobium japonicum; seed inoculation with Azospirillum brasilense; application of soil bio-activator; seed inoculation with B. japonicum and A. brasilense; seed inoculation with B. japonicum and application of soil bio-activator; seed inoculation with A. brasilense and application of soil bio-activator; and seed inoculation with B. japonicum and A. brasilense and application of soil bio-activator. In the morphometric analysis, plants inoculated with B. japonicum presented a greater number of nodules compared to the control. The co-inoculation associated with use of soil bio-activator increased the chlorophyll relative content, at the beginning of the cycle, in 6.37% in relation to the control. In gas exchange analysis, the isolated use of soil bio-activator obtained higher intrinsic water use efficiency (iWUE) in V₄. No increases in relation to the control were observed in the other variables evaluated, rejecting the hypothesis that co-inoculation associated with the use of soil bio-activator would promote increases in morphometric, physiological and productive characteristics of the soybean crop.

Highlighted Conclusions
1. The use of soil bio-activator associated with inoculation and coinoculation of Bradyrhizobium japonicum and Azospirillum brasilense does not provide increases in morphometric, physiological, and productive variables of the soybean crop.
2. Further studies are needed on the influence of soil bio-activators on the bacteria used in this study, enabling further verification of their applicability.

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In vitro rooting and acclimatization of ‘Marubakaido’ apple rootstock using indole-3-acetic acid from rhizobacteria
Juliana Aparecida Souza^1,3, Jean Carlos Bettoni¹, Murilo Dalla Costa², Tiago Celso Baldissera², João Frederico Mangrich dos Passos² and Silmar Primieri^3
1The New Zealand Institute for Plant and Food Research Limited, Palmerston North, Manawatu, New Zealand.
²Agricultural Research and Rural Extension of Santa Catarina, Santa Catarina, Brazil.
³Federal Institute of Education, Science and Technology of Santa Catarina, Lages, Santa Catarina, Brazil.

Abstract
Rooting tissue-cultured shoots and acclimatizing the rooted plantlets are key final steps in successful micropropagation protocols. We assessed the effect of indole-3-acetic acid (IAA) from synthetic and biological sources for effects on in vitro rhizogenesis and acclimatization stages in micropropagated ‘Marubakaido’ (Malus prunifolia) apple rootstock. Shoots of 3 cm length were transferred to rooting medium, composed of Murashige and Skoog (MS) medium supplemented with up to 2 mg L^-1 AIA and grown for 60 days in a controlled environment before assessment. Root initiation rate, callus formation, dry-root biomass, dry-shoot biomass, root length, root volume and diameter were evaluated. After the acclimatization stage, survival rate was determined. The root initiation rate of micropropagated ‘Marubakaido’ apple rootstock was higher in culture media supplemented with IAA, independent of the source. Callus formation at the base of shoots was higher according to increases of synthetic IAA concentration. In contrast, there was no callus formation from shoots cultured on MS medium supplemented with bacterial. ‘Marubakaido’ shoots rooted in vitro were successfully acclimatized. Survival of the plantlets during acclimatization was affected by both IAA concentration and source. Plant survival rate at the acclimatization stage decreased from 96% to 66% as the concentration of synthetic IAA increased. ‘Marubakaido’ inoculated in MS medium supplemented with bacterial IAA had thinner roots without callus formation, resulting in higher survival (up to 98 %) during acclimatization. Strain N39 was particularly effective in inducing in vitro rooting and acclimatization of ‘Marubakaido’ apple rootstock, resulting in high-quality rooted plantlets.

Highlighted Conclusion
1. Supplementation with indole-3-acetic acid (IAA) produced by rhizobacteria during in vitro rooting of apple rootstock increased survival rates at the acclimatization stage, and may be an efficient and sustainable alternative to synthetic IAA within micropropagation protocols.

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Heritability estimates and genetic distance of s₁ progenies from landrace maize populations
Mauricio Ferrari¹, Ivan Ricardo Carvalho²*, Alan Junior de Pelegrin¹, Vinícius Jardel Szareski¹, Maicon Nardino¹, Tiago Corazza da Rosa¹, Nathan Löbler dos Santos¹, Tamires da Silva Martins¹, Velci Queiróz de Souza³, Antonio Costa de Oliveira¹ and Luciano Carlos da Maia^1
1Universidade Federal de Pelotas, Capão do Leão, RS, Brasil.
²Universidade Regional do Noroeste do Estado do Rio Grande do Sul, Ijuí, RS, Brasil.
³Universidade Federal do Pampa, São Gabriel, RS, Brasil.

Abstract
The aim of study to estimate the broad sense heritability of S1 progenies and to quantify the genetic variance through multivariate analyzes of S1 progenies from landrace maize populations grown in the southern region of Rio Grande do Sul. The experimental design utilized was the augmented blocks, with ten S1 progenies groups (Amarelão, Argentino Branco, Argentino Amarelo, Branco Vermelho Indio, Branco Oito Carreiras, Caiano Rajado, Cateto Branco, Criolão Dente de Ouro and BRS Planalto), and two commercial controls, the simple cross hybrids Pioneer 30F53 and Agroeste 1590, allocated in four repetitions. The traits grain depth and spike insertion height express the largest estimates of broad sense heritability. The S₁ progeny Argentino Amarelo provides the largest estimates of broad sense heritability for the set of evaluated traits. The S₁ progenies Caiano Rajado, Criolão, Branco Roxo Índio, BRS Planalto, Dente de Ouro, Amarelão and Branco Oito Carreiras have similar heritability patterns for the studied traits, allowing to employ a similar selection strategy in the next generations. The S₁ progenies from landrace maize populations present genetic variability for the agronomic traits studied.

Highlighted Conclusions
1. The traits grain depth and spike insertion height express the largest estimates of broad sense heritability.
2. The S₁ progeny Argentino Amarelo provides the largest estimates of broad sense heritability for the set of evaluated traits.
3. The S₁ progenies Caiano Rajado, Criolão, Branco Roxo Índio, BRS Planalto, Dente de Ouro, Amarelão and Branco Oito Carreiras have similar heritability patterns for the studied traits, allowing to employ a similar selection strategy in the next generations.
4. The S₁ progenies from landrace maize populations present genetic variability for the agronomic traits studied.

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Time of potato plant harvest in soilless cultivation for screening phosphorus use efficient genotypes
Darlene Sausen¹, Ivan Ricardo Carvalho², Franciele Antônia Neis¹, Suzi Cerezer Uliana¹, Ritieli Baptista Mambrin³, Raíssa Schwalbert³, Miriam da Silva Tavares⁴ and Fernando Teixeira Nisoloso^3
1Federal University of Santa Maria, Santa Maria, RS, Brazil.
²Regional University of Northwest of Rio Grande do Sul, Ijuí, RS, Brazil.
³Centro De Ensino Superior Riograndense, Marau, RS, Brazil.
⁴Goias State University, Posse, GO, Brazil.

Abstract
The shorter the duration of the selection process of potato genotypes more efficient in the use of P, the lower the casting time of a new plant variety in the market and its growing field, where effectively verify the reduction of use of phosphate fertilizers, which may help to increase the sustainability of the potato production chain.  Therefore, the objective of this study was to determine the time of collection of potato plants grown in a closed system with sand as substrate and subjected to P restriction in nutrient solution aiming at the selection of more efficient genotypes on the P use. For this purpose, seven potato genotypes (SMIC 148-A, Dakota Rose, Sminia 793103-3, SMIB 106-7, 212-3 SMIF, SMIJ 319-1 and P 150), were grown in a closed soilless system with sand as substrate and nutrient solution containing two P levels (low: 2.32mg L^-1; and high: 23.2mg L^-1). The plants were harvested three sampling times (18, 39 and 62 days after transplanting (DAT)). The data showed that it is not advisable to use the plant growth assessment carried out until 18 DAT for screening of genotypes efficient in the use of phosphorus. However, at 39 DAT most potato genotypes already showed differences in all growth parameters evaluated between P levels, enabling the selection of the most efficient in P use and therefore not necessary cultivation by the end of the crop cycle.

Highlighted Conclusions
1. Selection of potato genotypes for P efficiency based on evaluations performed until 18 days after transplanting is not recommended.
2. At 39 days after transplanting, most potato genotypes already exhibit differences between the levels of P for all growth parameters evaluated, allowing the selection of the most efficient ones with respect to P, thus eliminating the need for cultivation until the end of the crop cycle.

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Inoculation methods of Azospirillum brasilense associated to the application of soil bioactivator in the maize crop
Alexandre Wegner Lerner¹, Vandeir Francisco Guimarães², Tauane Santos Brito²*, Victor Matheus Röske², Roberto Cecatto Junior², André Silas Lima Silva² and Julia Carolina Weizenmann^2
1Case IH, Sorocaba, São Paulo, Brasil.
²Universidade Estadual do Oeste do Paraná, Cidade, PR, Brasil.

Abstract
Seeking greater productivity, cost reduction and greater sustainability, plant growth promoting bacteria and soil bioactivators become a viable alternative for maize producers. The objective was to evaluate the effects of inoculation and foliar application of Azospirillum brasilense associated with the application of soil bioactivator on morphometric, physiological and productive characteristics of the maize crop.  Conducted in the field, the experimental design adopted was randomized blocks, with 4 repetitions and the following treatments: control; seed inoculation with Azospirillum brasilense (100 mL per 60,000 seeds); foliar spraying of A. brasilense at the V5 stage of maize; application of soil bioactivator; seed inoculation with A. brasilense + foliar spraying of A. brasilense at the V5 stage of maize; seed inoculation with A. brasilense + application of soil bioactivator; foliar spraying of A. brasilense at the V5 stage of maize + application of soil bioactivator; seed inoculation with A. brasilense + foliar spraying of A. brasilense at the V5 stage of maize + application of soil bioactivator. At the V8, VT and R3 stages morphometric and physiological evaluations were performed. At the VT stage, the inoculation methods of A. brasilense and the application of bioactivator were significant only for the dry mass of reproductive structures. In the R3 stage, plants inoculated by foliar spraying of A. brasilense together with the application of soil bioactivator showed statistically superior heights. The inoculation methods with A. brasilense and the application of soil bioactivator did not influence morphometric attributes throughout the development of maize, not influencing physiological variables. The production components and yield were not affected by the treatments applied.

Highlighted Conclusions
1. The methods of inoculation with Azospirillum brasilense and the application of soil bioactivator did not influence morphometric attributes throughout maize development, and did not influence physiological variables.
2. The yield and production components were not affected by inoculation with A. brasilense and application of soil bioactivator.

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Weed management with pre-emergent herbicides in soybean crops
Helis Marina Salomão¹, Michelangelo Muzell Trezzi¹, Matheus Viecelli², Fortunato De Bortoli Pagnoncelli Junior², Felipe Patel², Leticia Damo³ and Gilvane Frizzon^2
1Federal University of Technology, Pato Branco, PR, Brazil.
²Independent Agronomist, Brazil.
³Federal University of Viçosa, Viçosa, MG, Brazil.

Abstract
The use of pre-emergent herbicides in soybean crops is fundamental, among other reasons, to maintain a clean crop in the initial stages, alter mechanisms, and consequently manage weed resistance. However, there is a considerable demand for information about the efficiency and selectivity of systems with residual herbicides applied in different modalities. This study evaluated the efficiency and selectivity of pre-emergent herbicides doses applied singly or mixed in a tank on soybean crops. The experiment was installed in randomized block design with 21 treatments and four repetitions. The treatments were composed of weeded and unweeded witnesses and pre-emergent application of isolated S-metolachlor or the herbicides diclosulam, flumioxazin, and sulfentrazone isolated or together with S-metolachlor in different doses with the addition of post-emergent S-metolachlor (soybean stage V2). Associations of residuals herbicides applied in pre-emergence or sequential mode increased the control levels of mono and dicotyledonous weeds. The treatments, including single or associated diclosulam and the systems with S-metolachlor sequentially, caused the most significant toxicity (up to 17%) for soybeans. High doses of S-metolachlor (2592.0 g ha^-1), diclosulam (33.6 g ha^-1), and the associations of S-metolachlor + diclosulam, S-metolachlor + flumioxazin, and S-metolachlor + diclosulam with sequential S-metolachlor should be avoided to obtain higher levels of soybean yield. The use of pre-emergent herbicides demonstrated to be an efficient and viable option to control weeds in soybean crops.

Highlighted Conclusions
1. The association of residual herbicides generally increases the control levels of mixed natural infestations of mono and dicotyledons weeds.
2. It is possible to associate the grain yield of a soybean crop with the control efficiency of weed species and the toxicity of herbicides in the crop.

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An algal sulphated polysaccharide capable of reducing mycotoxin biosynthesis by Fusarium
Rafael Dal Bosco Ducatti¹, Siumar Pedro Tironi² and Sergio Miguel Mazaro^1
1Federal University of Technology – Paraná (UTFPR), Pato Branco, PR, Brazil.
²Federal University of Fronteira Sul (UFFS), Chapecó, SC, Brazil.

Abstract
The incidence of Fusarium sp. in maize, besides causing drops in yields also causes the bromatological quality of the final product to decrease and mycotoxin accumulation to increase. Nineteen field trials have been performed in 4 different states of Brazil during three consecutive harvest seasons using 17 different maize cultivars aiming at assessing the use of carrageenan as a biological compound to decrease mycotoxin biosynthesis and accumulation and, increase maize silage yields and quality. Overall, carrageenan has proven to raise the bromatological quality of the silage, increase yields and decrease fumonisine and deoxynivalenol contamination by 50.4% and 45.7%, respectively.

Highlighted Conclusion
Carrageenan has the capability to help on the suppression of DON and FUMO biosynthesis/accumulation and to help on the increase of the bromatological quality of maize silage.
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Phosphorus partition, phytic acid concentration and grains productivity of beans cultivars as a response to phosphate nutrition
Ritieli Baptista Mambrin¹, Darlene Sausen², Diogo Moura¹, Ivan Ricardo Carvalho³, Vinícius Jardel Szareski⁴ and Giordano Gelain Conte^4
1Centro De Ensino Superior Riograndense, Marau, RS, Brasil.
²Universidade Federal do Rio Grande do Norte, Parnamirim, RN, Brasil.
³Universidade Regional do Noroeste do Estado do Rio Grande do Sul, Ijuí, RS, Brasil.
⁴Universidade Federal de Pelotas, Capão do Leão, RS, Brasil.

Abstract
The objectives of this work were to evaluate the phosphorus partition in tissues, in different growth stages, the phytic acid concentration in grains and the beans yield, as a response to the phosphorus supply in the culture environment, and the analysis of the association between these characters. The experiments were conducted in non-acclimatized greenhouse. The data was submitted to variance analysis, considering all the effects as fixed, with exception of the error, which was considered random. Since it was significant the effect of the triple interaction phosphorus concentration x genotype x growing season (C x G x E), it was realized the deployment of it in three double interactions with the use of complex variance. The phosphorus values in common bean leaves at initial growing stages are close to the ones found in grains. For the genotypes Pérola and IPR88 Uirapurú, the highest phosphorus values in plants tissues and of phytic acid occurred in phosphorus concentrations in the nutritive solution between 1.38 and 2.00 mmol L^-1. Phosphorus concentrations in the nutritive solution between 1.37 and 1.96 mmol L^-1 result in higher phosphorus concentration in leaves at third trifoliate leaf, in stem at flowering, in leaves, stem and legumes at legumes filling and grains at maturation. Also, higher phytic acid concentration in grains, at the fall-winter and spring-summer seasons. The evaluation of phosphorus concentration in the vegetal tissues from the legume filling stage is promising and allows indirect selection to grains productivity.

Highlighted Conclusion
The concentration of P in plant tissues during the legume filling stage is promising and allows indirect genetic selection to grains productivity.
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Yield and economic losses caused by Corynespora cassiicola on soybean under chemical control
Deivid Sacon¹, Alexandre Jacques Bottan², Laura Caroline Zanella², Aline Netto² and Leandro Luiz Borges^3
1Instituto de Biotecnologia Aplicada à Agropecuária, Viçosa, MG, Brasil.
²ABC Agrícola, Sapezal, MT, Brasil.
³Universidade do Estado de Minas Gerais, Passos, MG, Brasil.

Abstract
Target Spot is an important disease in soybean caused by the necrotrophic fungus Corynespora cassiicola. Recently, this fungus has gained importance in large crops such as soybeans and for its insensitivity fungicides reports. In this study, three assays were carried out with different application treatments in order to evaluate fungicide applications to control Target Spot and their interference on soybean productivity. Different application treatments were tested including fungicide products, doses, mixtures and number of applications, as well as estimate the application’s economic viability. Cultivar TMG 2378 IPRO was used and the applications were performed with a CO₂ sprayer pressurized in a randomized block design with four replications. The harvest of 2.7 m² useful area in the plot center was carried out with a stationary plot harvester and the yield was estimated for kg ha^-1. For an economic analysis of the application treatments, the soybeans sale was considered at a fixed price of US$ 264 t^-1, while the operating cost at a value of US$ 8. The fungicides spraying cost was estimated in kg of grains ha^-1 based on the average of two budgets made. The fungicide mixtures bixafen+prothioconazole+trifloxystrobin+mancozeb and trifloxystrobin+ prothioconazole+mancozeb presented both yield increase and economic viability compared to control.

Highlighted Conclusion
Mixtures of bixafen+prothioconazole+trifloxystrobin+mancozeb and trifloxystrobin+ prothioconazole+mancozeb have yield and economic viability to control Corynespora cassiicola.
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Control of Ipomoea grandifolia and antioxidant enzyme activity with bentazon and glyphosate at times and soil water conditions
Helis Marina Salomão, Michelangelo Müzell Trezzi, Fortunato de Bortoli Pagnoncelli Junior, Adriano Suchoronczek, Matheus Viecelli and Katia Cristina Dalpiva Hartmann
Federal University of Technology (UTFPR), Pato Branco, PR Brazil.

Abstract
Weed management with herbicides requires favorable environmental conditions, that maximize efficiency, such as soil humidity and timing of application. The aim of this study was to assess the effect of the application timing of bentazon and glyphosate herbicides on the control and activity of antioxidant enzymes in Ipomoea grandifolia, under different conditions of soil water availability. Two experiments, one for each herbicide (bentazon and glyphosate), were conducted in a factorial design with four replicates. The first factor was the two rates of each herbicide (504 and 720 g i.a. ha^-1 of bentazon and 651 and 911.4 g i.a. ha^-1 of glyphosate). The second factor was the six application times (1 am; 5 am; 9 am; 1 pm; 5 pm and 9 pm). The third factor, soil water content (100% and 50% of field capacity). Plus, two controls without herbicide application. At 21 days after application (DAA) of bentazon and 28 DAA of glyphosate, the fresh mass of the aboveground plants was measured. In addition, the activities of the enzymes superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) were determined. For plants under water restriction, an increase of approximately 20% in fresh mass was observed compared in plants without water restriction, indicating lower control efficiency under water stress condition. For bentazon, at 1 pm has been observed the lowest herbicide efficiency, the other times were the most efficient, and did not differ. For glyphosate, the application at 9 am was the most efficient, while at 1 am provided the worst control efficiency. Higher CAT and SOD activities after bentazon application were observed at 1 pm. Among the three enzymes evaluated, SOD presented the highest activity after glyphosate application. Generally, the times of the day with the highest peak of enzymatic activity were distinct between with and without water restriction.

Highlighted Conclusions
1. Water restriction reduces the efficiency of bentazon and glyphosate.
2. Better efficiency for bentazon was observed at 1 am, 5 am, 9 am, 5 pm and 9 pm.
3. Better efficiency for glyphosate was observed at 9 am.
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