australian journal of crop science   AJCS

The study was carried out to assess the genetic diversity and population structure of okra collections from diverse geographic origin using selected polymorphic simple sequence repeat (SSR) markers. Thirty-two okra accessions collected from three geographic regions were genotyped using 16 selected SSR markers. The SSR markers generated a total of 71 loci of which 67% were polymorphic. Genetic distances among accessions ranged from 2.2 to 7.1, with a mean of 4.65. Gene diversity ranged from 0.10 to 0.78 with a mean of 0.52. Genetic clustering classified the accessions into three major clusters and four sub-clusters. Each cluster and sub-cluster consisted of accessions derived from different sources. Analysis of molecular variance revealed that 67%, 81% and 83% of the total genetic variation detected was found within populations of geographic origin, altitude and collection district, respectively. The observed moderate to high population differentiation could partly be attributed to limited germplasm exchange, agro-ecological differences, and partly by selection pressure. The present study revealed the presence of high genetic diversity and population divergence among okra collections from Ethiopia. The study demonstrated that a collection strategy for conservation of okra genetic resources should focus on sampling of representative genotypes covering wide geographic regions and altitudinal ranges of target agro-ecologies.

Pages 1032-1041 | Full Text PDF| Suppementary Data| doi: 10.21475/ajcs.20.14.07.p984
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Production of lettuce in NFT hydroponic condition at different planting seasons and irrigation systems

Cláudio Silva Soares, Alde Cleber Silva de Lima, Jeneilson Alves da Silva, Marina Suenia de Araújo Vilar, André Luiz Pereira da Silva, Joaquim Alves de Lima Junior, José Félix de Brito Neto

Department of Soil Fertility, Universidade Estadual da Paraíba – UEPB, Lagoa Seca, Paraíba, Brazil
Department of medical science – UNIFACISA, Campina Grande, Paraíba, Brazil
Department of Plant Production, Universidade Estadual Paulista – UNESP, Jaboticabal, São Paulo, Brazil
Department of Plant Production, Universidade Federal Rural da Amazônia – UFRA, Capanema, Pará, Brazil

Abstract
Hydroponics has drawn huge interests by Brazilians in semi-arid regions due to the lack of water and fertilizer use. The objective of this study was to evaluate the growth and yield of lettuce cultivars in the hydroponic system in two planting seasons and different irrigation regimes. The research was carried out in Campus II / UEPB and followed a 2 x 6 x 3 factorial scheme in randomized blocks, represented by two planting seasons (the summer and the winter), six lettuce cultivars (Elba, Great Lakes, Mimosa Rose, Simpson, American, Cristina), three irrigation regimes (15 min, 30 min, 45 min) and five replications. The hydroponic system used was the NFT. For nutrition, Hidrogood Fert® solution (Compound + Calcium + Iron) was applied. At the 40th day after sowing, green and dry leaf biomass, green stem biomass, leaf area, leaf area index and productivity were analyzed. After that, the variance analysis was performed by the F-test for 5% of probability and the Scott-Knott test for comparison of the averages. The high temperatures caused very small growth in the stem of the Simpson cultivars, independent of the irrigation regime used. Besides the highlight of the American cultivars, the other cultivars presented satisfactory performance in the climatic conditions of Lagoa Seca / PB.

Pages 1042-1047 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p1828
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Stalk dry mass and industrial yield of 16 varieties of sugar cane cultivated under water restriction

João Carlos Rocha dos Anjos*, Derblai Casaroli, José Alves Júnior, Adão Wagner Pego Evangelista, Rafael Battisti, Marcio Mesquita

Federal University of Goiás (UFG), College of Agronomy, Avenida Esperança, Campus Samambaia, 74690-900, Goiânia, GO, Brazil

Abstract
The great extension of the cultivated area, associated with the low water availability to supply the sugarcane demand in the periods of drought and the high evapotranspiration demand, requires varieties adapted to these specific conditions. The aim of this study was to assess 16 sugarcane varieties regarding the efficiency in water use (EWU) and in photosynthetically active radiation (PAR), cultivated under a water restriction, in the production of stalks dry matter, sugar and alcohol. The experiment was carried out in the Brazilian savannah biome, Goiás State, during the 2011/2012 crop year, in a randomized blocks design, with four repetitions. The treatments consisted of 16 varieties of sugarcane cultivated on a supply of only 50% of the water demand demanded by the crop. The EWU and EUPAR of the varieties were evaluated for the production of stalk dry mass (SDM), sugar and alcohol. During the crop cycle there was sufficient precipitation to supply the water demand of sugarcane; however, the irregular distribution of rainfall resulted in a water deficit of -697 mm during its cycle. The varieties IAC 91-1099, CTC-15, CTC-11, SP 86-0042 and IAC 87-3396 showed higher EWU and better photosynthetically active radiation for the production of stalks dry matter, sugar and alcohol. IACSP 94-2094 and CTC 09 varieties presented the same efficiency in industrial yield and lower dry matter yield than the five following varieties IAC 91-1099, CTC-15, CTC-11, SP 86-0042 and IAC 87-3396. Therefore, these last varieties are the most efficient in water use and photosynthetically active radiation aiming the stalks dry matter, sugar and alcohol production under water restriction.

Pages 1048-1054 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p1899
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Participatory variety selection of common bean (Phaseolus vulgaris L.) genotypes in the major bean producing areas of Ethiopia

Shiferaw G. Tigist1, Rob Melis, Julia Sibiya, Beyene Amelework*, Gemechu Keneni

Ethiopian Institute of Agricultural Research, Melkassa Agricultural Research Centre, P.O. Box 430, Adama, Ethiopia
African Center for Crop Improvement, University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa.
Agricultural Research Council, Vegetable and Ornamental Plant, Private Bag X293, Pretoria, 0001, South Africa
Ethiopian Institute of Agricultural Research, Holeta Agricultural Research Centre, P.O.Box 2003, Addis Ababa, Ethiopia

Abstract
This study was conducted to identify suitable parental genotypes for breeding for resistance to bruchid and to identify the farmers’ preferred traits in common bean. For this study, 144 diverse common bean genotypes were planted in an alpha lattice design, with 3 replications at 3 locations. Participatory variety selection were done using 20 farmers at each location. Farmers identified a number of criteria for selecting suitable varieties. Yield and yield-related traits were ranked as the most important selection criteria by all farmers at all locations. However, women ranked culinary traits as the top criteria, while men were more interested in marketable traits. From the 144 genotypes, farmers selected the 10 best genotypes in all the locations. The majority of the genotypes selected at Melkassa and Alemetena were small white-seeded released varieties and breeding lines. However, all the genotypes selected at Arsi Negele were predominantly landraces of small red-seeded beans. Traits such as earliness and resistance to storage insect were important in Melkassa and Alme tena but received less attention in Arsi Negele. The integration of the farmers’ selection preferences with the breeders’ criteria can improve the efficiency of plant breeding by developing crop varieties that better fit the specific needs of the farmers.

Pages 1055-1063 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p1924
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Production and quality of zucchini seeds after applying sulphur as top dressing and organic compost at planting

Estefânia Martins Bardiviesso*, Natália de Brito Lima Lanna, Ariel Santivañez Aguilar, Sara Raissa Brito Bezerra, Raíra Andrade Pelvine, Pâmela Gomes Nakada Freitas, Francisca Zildélia da Silva, Marcela Sant’ Anna Cordeiro da Silva, Antonio Ismael Inácio Cardoso

School of Agriculture, São Paulo State University, Botucatu, Sao Paulo, Brazil
School of Agriculture, São Paulo State University, Dracena, Sao Paulo, Brazil
School of Agriculture, São Paulo State University, Piracicaba, Sao Paulo, Brazil

Abstract
The recommendation of fertilization for zucchini (Cucurbita pepo) cultivation is usually made with no differentiation from the other cucurbit crops. Thus, there is a need to examine the doses of fertilizers used for zucchini production, as well as the suitability for cultivars, seasons, and cultivation regions. The aim of this study was to evaluate the influence of sulfur doses at topdressing fertilization and the supply of organic compost at planting on the production and quality of zucchini seeds. A total of eight treatments were studied in a randomized block design with a factorial scheme 4x2, corresponding to four sulfur doses at topdressing (0, 57, 114 and 173 kg ha-1 of S), in the presence (30 t ha-1) and absence of organic compost at planting. The fruits were harvested 62 DAT, and after harvest, the fruits remained in rest for 15 days in order to reach the uniformity of the physiological maturity of the seeds. The production characteristics evaluated were average fresh weight, diameter, dry weight and length of the fruits, fruit yield per plant, weight of a thousand seeds, number and seed weight. Regarding the seed quality, the percentage of germination, germination speed index, first count of the germination test, and electric conductivity, were evaluated. The supply of organic compost at planting had a positive effect on the production and physiological quality of the seeds of zucchini produced. The sulfur applied at topdressing improved the presence of the organic compost and also the production of seeds. Hence, it is recommended to apply 30 t ha-1 of organic compost at planting in association with 57 kg ha-1 of S at topdressing for higher seed yield and quality.

Pages 1064-1071 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2049
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Intercropping of sorghum with Paiaguas palisadegrass in a crop-livestock integration system for pasture recovery

Charles Barbosa Santos, Kátia Aparecida de Pinho Costa, Wender Ferreira de Souza, Alessandro Guerra da Silva, Victor Costa e Silva, Itamar Pereira de Oliveira, Eduardo Valcacer Brandstette

University of Rio Verde, College of Agricultural Science, Rio Verde, Goiás, Brazil
Goiano Federal Institute, Graduate Program in Agricultural Sciences and Animal Science, Rio Verde, Goiás, Brazil 

Abstract
Intercropping systems have become an interesting alternative for grain and forage production because they are sustainable systems that reduce carbon emissions in degraded pasture areas. However, few studies have used forage species recently introduced into the market, and more studies that assess the performances of these species in integrated systems are needed. Therefore, the objective of this study was to evaluate the agronomic characteristics of intercropped sorghum and Paiaguas palisadegrass (including the species name) in a crop-livestock integration system for pasture recovery. The field experiment was conducted in the municipality of Rio Verde, Goiás, Brazil, using a randomized block design with four replications. The treatments consisted of the following forage systems: monocropping of sorghum, monocropping of Paiaguas palisadegrass, row intercropping of sorghum with Paiaguas palisadegrass, interrow intercropping of sorghum with Paiaguas palisadegrass and intercropping of sorghum with oversown Paiaguas palisadegrass. To obtain a desired population of 240,000 plants ha-1, 12 seeds of sorghum and 5 kg of viable pure seeds of the forage species were planted per meter and hectare, respectively. The growth of Paiaguas palisadegrass in the same row as sorghum reduced the sorghum grain yield. The intercropping of sorghum with oversown Paiaguas palisadegrass hindered the initial development of Paiaguas palisadegrass in terms of plant height and number of tillers due to shading, and this effect was reflected in the dry mass production. Row and interrow intercropping provided higher dry mass production without affecting the forage quality. Therefore, the interrow intercropping of sorghum with Paiaguas palisadegrass was found to be a promising agricultural technique for grain and forage production that could be used for the establishment of new pastures or pasture recovery.

Pages 1072-1080 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2216
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Effects of post-harvest hot water treatments on the fungi contamination, physiology and quality of rock melon fruit

M.M. Abubakar, M. Norida*, M.Y. Rafii, J.J. Nakasha

Laboratory of Climate Smart Food Crop, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia
Department of Agriculture Technology, Faculty of Agriculture, Universiti Putra Malaysia
Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia

Abstract
During the postharvest management of fruits and vegetables, the losses range from 10 to 30% of the entire production. This is due to numerous causes, but the most important reason is infestation by fungi. Many synthetic fungicides are employed for postharvest treatment of fruit and vegetables throughout the world. However, fungicidal residues often represent a significant threat to human health. The current study examined the use of hot water treatments on rock melon fruit. Hot water treatments at 55℃ was arranged into four treatments of different dipping periods of 0 minutes (control), 1 minute, 2 minutes, and 3 minutes. The postharvest hot water treatments on rock melon fruit were found to increase the shelf life up to 21 days by minimizing the weight loss, maintaining firmness, preventing the damage of sucrose, retaining the rind size, maintaining the fruit appearance, and reducing fungal infection. The one-minute dip was more effective than other treatments. The treatment successfully extends the shelf life of rock melon fruit quality for the market until three weeks of storage at 21 ± 1 ℃ compared with the control, which was only stored for one week. The results showed the importance of hot water treatments as an alternative to fungicides or chemical treatments, which have a high risk to the health of consumers. Hot water treatment is economical and easier to access than the chemical treatments.

Pages 1081-1087 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2218
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The application of zinc fertilizer reduces Fusarium infection and development in wheat

Muhammed Alsamir, Esraa Al-Samir, T A Kareem, Mohammed Abass, Richard Trethowan

Plant Breeding Institute, Faculty of Agriculture and Environment, University of Sydney, 107 Cobbitty Road, Cobbitty, NSW 2570, Australia

Biology Department, College of Science, University of Basra, Iraq 
Collage of Agriculture Engineering Sciences, University of Baghdad, Iraq
Plant Protection, College of Agriculture, University of Basrah, Iraq

Abstract

Fusarium pseudograminearum and Fusarium graminearum commonly cause crown rot (FCR) and head blight (FHB) in wheat, respectively. Disease infection and spread can be reduced by the deployment of resistant cultivars or through management practices that limit inoculum load. Plants deficient in micronutrients, including zinc, tend to be more susceptible to many diseases. On the other hands, and zinc deficiency in cereals is widespread in Australian soils. Zinc deficiency may have particular relevance to crown rot, the most important and damaging Fusarium disease of wheat and barley in Australia. Four wheat genotypes; Batavia, Sunco and two lines from the International Maize and Wheat Improvement Center (CIMMYT) were tested for response to FHB and FCR under differing levels of Zn,1 and 2 g/kg and its correlation with disease severity. Sunco and CIMMYT line 146 were previously rated resistant to crown rot and Zn efficient. Zn application 2 g/kg soil enhanced resistance to FCR of the disease susceptible and Zn in-efficient in Batavia and 48 as its recorded 0.75 and 0.5 respectively compared to Sunco and CIMMYT line 146 as it recorded 0.2 and 0.3 respectively, but did not increase resistance to FHB. However, Zn application did enhance the resistance of Zn efficient genotypes to FHB. Results suggest that higher levels of Zn fertilization could reduce the expression of Fusarium diseases in wheat.

Pages 1088- 1094 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2235
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Post-emergence application of glufosinate on maize hybrids containing the phosphinothricin acetyltransferase gene (pat)

Fábio Henrique Krenchinski*, Caio Antonio Carbonari, Edicarlos Batista de Castro, Danilo Morilha Rodrigues, Victor José Salomão Cesco, Renato Nunes Costa, Edivaldo Domingues Velini

Department of Plant Breeding and Production, São Paulo State University (UNESP), School of Agriculture, Botucatu, Brazil

Abstract
Several maize hybrids that present the phosphinothricin acetyltransferase gene (pat) are available in the market. However, these hybrids have different resistance levels to glufosinate herbicides. The objective of the present work was to evaluate the resistance of maize hybrids containing the pat gene (as a selection marker) to glufosinate. Field experiments were conducted in two sites in the 2016/2017 crop season, using a randomized block design with a 2×7 factorial arrangement and four replications. The treatments consisted of two glufosinate rates (0 and 500 g ha-1) and seven maize hybrids, six containing the pat gene as a selection marker (Herculex®, Agrisure-TL®, Herculex Yieldgard®, Leptra®, Viptera-3®, and Power-Core®) and one without the pat gene (VT PRO®). Two field experiments were conducted in different sites. The analyzed variables were: ammonia accumulation, electron transport rate (ETR), percentage of injuries, 100-grain weight, and grain yield. The glufosinate-susceptible maize hybrid presented higher ammonia accumulations, lower ETR, and high percentage of injuries (100%), which caused total loss of grain production. Considering the evaluated glufosinate-resistant maize hybrids, Viptera-3 and Agrisure-TL presented the highest ammonia accumulations and percentages of injuries, and lower ETR than the other hybrids. The grain yield of glufosinate-resistant maize hybrids was not reduced due to the application of the 500 g ha-1 of glufosinate. Thus, glufosinate-resistant maize hybrids containing the pat gene are resistant to the application of 500 g ha-1 of glufosinate, and this practice can be recommended for maize crops.

Pages 1095-1101 | Full Text PDF|doi: 10.21475/ajcs.20.14.07.p2241
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An econometric model for demand of pulpwood market in Brazil

Humberto Angelo, Tomas V. Angelo, Alexandre N. de Almeida, Pedro G. A. Vasconcelos, Mauro Magliano, Alexandre A. Brasil, Álvaro N. de Souza, Eder P. Miguel

Department of Forestry Engineering, University of Brasilia (UnB), DF, Brazil
Amsterdam school of economics, University of Amsterdam, Netherlands

Abstract
The pulp industry has a great importance to the economy of Brazil and despite of being one of the biggest producers in the world this industry is still expanding in the country. In spite of the importance of the planted forests as main source for the pulp industry and other products, pulpwood for the cellulose market has received little attention in Brazil. Therefore, the objective of this research is the study of pulpwood demand in Brazil from 1994 to 2016, using econometric tools, where the demand equation was specified and adjusted by the Ordinary Least Squares method. The results showed that pulpwood price and the capacity of the pulp industry explain the pulpwood demand with good econometric results. The pulpwood demand is inelastic to price fluctuations and elastic to installed capacity. These results are consistent with the international estimations and they can assist projecting policies that promote more rational and sustainable management of the wood and consequently the forests.

Pages 1102-1108 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2244
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Phenotypic response of barley landrace and its wild progenitor Hordeum spontaneum from Jordan to salt stress

Adel H. Abdel-Ghani, Khalid Al-Abbsi, Nael Thaher*, Saddam Al-Dalain, Ghaid Al-Rabadi, Farah Al-Nasir

Department of Plant Production, Faculty of Agriculture, Mutah University, Jordan
National Agricultural Research Centre, Amman, Jordan
Al-Shoubak University College, Al-Balqa Applied University, Jordan
Department of Animal Production, Faculty of Agriculture, Mutah University, Jordan

Abstract
Populations of barley landrace [Hordeum vulgare (L.)] and wild barley progenitor [Hordeum spontaneum (L.)] were collected from 13 diverse eco-geographical regions in Jordan. In addition to two check varieties (Rum and Acsad 165) were collected from farmers’ fields. In total, 28 genotypes were evaluated during germination, early seedling and maturity stages for salt tolerance. Barley populations were exposed to tap water of 0.85 dS m-1 and saline solutions (NaCl, CaCl2 and MgSO4) of 4, 8, 12 and 16 dS m-1. Final germination percentage, the lengths of shoot and seminal root, growth and yield related traits were significantly decreased by increasing the level of salinity. Proline content was increased by increasing the level of salinity. A high level of salinity of 16 dS m-1 had a strong impact on reduction of grain yield and other agronomic traits in the examined populations. A considerable variation among populations was detectable. Barley landrace and wild barley that were collected from Tafila region were the most tolerant grown populations in Jordan. Interestingly, the ranking pattern of these two populations at the germination and seedling related-traits was consistent with the ranking pattern at the maturity phase. In conclusion, this study indicates that barley landrace and wild barley populations are potential donors for genes of salt tolerance that can be used to enhance salinity tolerance in barley.

Pages 1109-1120 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2277
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Soil compaction affects the silage quality of sunflower and Paiaguas palisadegrass (Brachiaria brizantha) grown on a Latosol in the Brazilian savanna

Adalto José de Souza Linhares, Wainer Gomes Gonçalves, Savio Menezes Cabral, Marlete Ferreira de Brito, Eduardo Valcacer Brandstetter, José Fausto Guimarães Silva, Kátia Aparecida de Pinho Costa, Wender Ferreira de Souza, Eduardo da Costa Severiano*

Federal Institute of Education, Science and Technology of Goiás, Ceres Campus, Rod. Go-154 Km 03, Cx. P. 51 CEP 76.300-000, Ceres - Goiás, Brazil
Federal Institute of Education, Science and Technology of Goiás, Rio Verde Campus, Rod. Sul Goiana Km 01, Cx. P. 66, CEP 75.901-970, Rio Verde - Goiás, Brazil
Federal Institute of Education, Science and Technology of Goiás, Urutaí Campus, Rod. Geraldo Silva Nascimento Km. 2.5, CEP 75.790-000, Urutaí - Goiás, Brazil

Abstract
On the basis of the natural seasonality of pastures during the dry season, preservation of forage, especially silage, is necessary. However, the effects of soil compaction within sunflower and grass crop fields on the nutritional quality of the silage produced are unknown. Therefore, the aim of this study was to evaluate the fermentation and nutritional quality characteristics of sunflower silage under both monocropping and intercropping systems [with Paiaguas palisadegrass (Brachiaria brizantha)] under various degrees of soil compaction. A split-plot randomized complete block design was adopted. In the main plots, the treatments were bulk density values affected by the following traffic intensities: 0, 2, 10 or 30 passes of a tractor with tire wheels weighing 4.9 Mg. The subplots involved forage systems composed of sunflower as a monocrop or intercropped with Paiaguas palisadegrass. The fermentation, nutritional characteristics and in vitro digestibility of the silage were evaluated. Under the various aforementioned conditions, the agronomic characteristics of the forage were affected by increased soil compaction, resulting in changes in the fermentation and nutritional characteristics of the silage. The results showed that intercropping with Paiaguas palisadegrass and adequate proportions of sunflower allow good fermentation. This study recommends the adoption of practices that mitigate soil compaction and intercropping because of the increased forage productivity and the possibility of the indirect renewal of the pasture.

Pages 1121-1130 | full Text PDF| doi: 10.21475/ajcs.20.14.07.p2294
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Soil compaction affects sunflower and Paiaguas palisadegrass forage productivity in the Brazilian savanna

Adalto José de Souza Linhares, Wainer Gomes Gonçalves, Savio Menezes Cabral, Marlete Ferreira de Brito, Eduardo Valcacer Brandstetter, José Fausto Guimarães Silva, Kátia Aparecida de Pinho Costa, Wender Ferreira de Souza, Eduardo da Costa Severiano*

Federal Institute of Education, Science and Technology of Goiás, Ceres Campus, Rod. Go-154 Km 03, Cx. P. 51 CEP 76.300-000, Ceres - Goiás, Brazil
Federal Institute of Education, Science and Technology of Goiás, Rio Verde Campus, Rod. Sul Goiana Km 01, Cx. P. 66, CEP 75.901-970, Rio Verde - Goiás, Brazil
Federal Institute of Education, Science and Technology of Goiás, Urutaí Campus, Rod. Geraldo Silva Nascimento Km. 2.5, CEP 75.790-000, Urutaí - Goiás, Brazil

Abstract
Integrated crop-livestock systems maximize land use, infrastructure and labor; diversify production; and minimize costs, thereby reducing risks and adding value to agricultural products. However, growing mechanically harvested crops can negatively affect soil structure, reducing plant biomass productivity. The present study aimed to evaluate soil compaction and its effects on the forage productivity of sunflower and Brachiaria brizantha cv. BRS Paiaguas during the second cropping period. The experiment was conducted as a split-plot randomized complete block design with four replications. Four compaction levels represented by traffic from an agricultural tractor were established: 0 (absence of compaction), 2, 10 and 30 passes over the same spot. Two forage systems were established in the subplots: sunflower grown solely as a monocrop (40,000 plants ha-1) or intercropped with Paiaguas palisadegrass (10 plants linear m-1). The following parameters were quantified: soil bulk density, plant height, capitulum diameter and 1000-achene weight for sunflower; stem length and the leaf/stem ratio for Paiaguas palisadegrass; and total and partitioned forage productivity. The results showed that sunflower was highly sensitive to soil compaction and that the development and productivity of this species decreased in response to the greatest bulk density, which in turn affected the Paiaguas palisadegrass. Overall, intercropping is recommended for increased forage productivity.

Pages 1131-1139 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2305
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Application of metal nanoparticles for pre-sowing treatment of spring barley seeds

Arthur Gagikovich Yablokov, Olga Aleksandrovna Bogoslovskaya*, Irina Pavlovna Olkhovskaya, Natalya Nikolaevna Glushchenko

V.L. Talrose Institute for Energy Problems of Chemical Physics at N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119334, 38/2 Leninsky pr., Moscow, Russian Federation

Abstract
This paper presents data on the pre-sowing treatment of spring barley (Hordeum vulgare L.) seeds by polymer coating with metal nanoparticles (NPs) affecting on seed germination and morphometric parameters of seedlings. Metal NPs [Fe (56.0 ± 0.9 nm, phase composition: Fe0 -27.9 ± 2.1%, Fe3O4 - 72.1 ± 3.6%); Zn (60.6 ± 3.7 nm, phase composition: Zn0 - 100%); Cu (65.0 ± 1.2 nm, phase composition: Cu0 - 100%)] were incorporated into a polymer coating about 10 microns thick, consisting of Na-carboxymethyl cellulose (Na-CMC) and polyethylene glycol-400 (PEG-400), with a dye rhodamine 6G (Rh6G). We developed and studied polymer compositions as with individual NPs in concentrations 10-4% - 10-10% and their combinations. To compare effects of NPs with metal ions, we tested polymer film coating with metal sulfates in equivalent amounts. Pre-sowing treatment of barley seeds with metal NPs or metal ions in the polymer coating affected germination, fresh green and root mass (FM and RM) of seedlings. Film thickness was less than 10% of the caryopsis shell. The surface of seeds treated with the polymer composition was uniform. The defects and irregularities were smoothed. There were no significant differences in the endosperm structure on sections of the treated and control samples. Iron, zinc and copper NPs composition at 10-8%, 10-4% and 10-8% concentrations were the best in laboratory experiments. In the field trials, it stimulated barley crop yields and decreased the moisture content of the bunker grain compared with the control.

Pages 1140-1149 | Full Text Pdf| doi: 10.21475/ajcs.20.14.07.p2366
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Physicochemical and rheological properties of the derivatives of Ningmai 9 wheat and their relationship with sugar-snap cookie diameter

Pingping Zhang*, Jinbao Yao, Hongxiang Ma, Guicheng Song

Institute of Food Crops, Jiangsu Academy of Agricultural Sciences/Jiangsu Collaborative Innovation Center for Modern Crop Production, 50 Zhongling Street, Nanjing, Jiangsu 210014, China

Abstract
In recent years, the annual demand for soft wheat in China has exceeded six million metric tons. The development of soft wheat is an important objective in the Yangtze River Basin winter wheat region in China. Ningmai 9 is a soft wheat cultivar widely used as a parent in the soft red winter wheat breeding program. However, the physicochemical and rheological properties of Ningmai 9 and its derivatives remain unknown. In this study, Ningmai 9 and its thirty-one derivatives were grown in Nanjing in Jiangsu Province in two successive cropping seasons from 2015 to 2017. The kernel samples were analyzed for milling quality, solvent retention capacity (SRC), alveograph parameters, and sugar-snap cookie diameter. The flour protein content was not significantly associated with any other quality trait. P, L, P/L (the ratio of tenacity to extensibility), alveograph deformation work (W), and four types of SRC were significantly correlated with sugar-snap cookie diameter. Compared to Ningmai 9, seven wheat genotypes had relatively better cookie quality and lower SRC and P values. A multiple regression model with water SRC (WSRC) as a variable explained 72.5% of the total variation in cookie diameter. These results suggest that decreasing SRC and gluten strength is the key to improving soft wheat breeding programs.

Pages 1150-1156 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2451
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Enhancement of rice (Oryza sativa L.) physiological and yield by application of nano-titanium dioxide

Rutairat Phothi, Chonlada Dechakiatkrai Theerakarunwong*

Environmental Science Program, Faculty of Science and Technology, Nakhon Sawan Rajabhat University, Nakhon Sawan 60000, Thailand
Chemistry Program, Faculty of Science and Technology, Nakhon Sawan Rajabhat University, Nakhon Sawan 60000, Thailand

Abstract
Engineered nanoparticles (ENPs) are reported as potentially response to rice physiological and production. The research aimed to investigate the effects of suspended nano-titanium dioxide (sn-TiO2), which is non-toxic to ecology and on the physiology and yield of Thai rice. Selected rice cultivars of RD41 were soaked and sprayed with three difference concentrations of sn-TiO2 (T0.01, T0.02, T0.03 and C) through growing period. Tiller number per plants, stem height and leaf chlorophyll of rice RD41 cultivars were analyzed at tillering (40 days), flowering (70 days), and final harvesting (100 days), whereas the biomass and yield were evaluated at final harvesting (100 days). The results showed the concentration of T0.03 had highest effects on rice RD41 for all studies, which showed non-significance of differences at p <0.05 compared to T0.02. Application of T0.01, T0.02 and T0.03 treatments increased total biomass 33.69, 42.66 and 47.91 g plant -1, respectively, compared to control (30.49). Application of T0.02 enhanced the plant growth and caused increases in the yield of rice, which impacted food availability. According to the results obtained, the function of sn-TiO2 played a positive role in many aspects. For instance, sn-TiO2 could increase light harvesting to activate the photosynthesis rate of rice RD41. Besides, nitrogen metabolism was improved by sn-TiO2 and stimulated protein and pigments content. Moreover, our observed decreasing in injury indices compared to the control group, which caused improvement in cell enlargement, cell elongation and plant growth. Atomic absorption spectrometric result ensured that there is no unforeseen Ti contamination in all part of rice. These findings are important supplementary factors to the application of sn-TiO2 for the crop yield and quality with a proper concentration for their benefits potential.

Pages 1157-1161 | full Text PDF| doi: 10.21475/ajcs.20.14.07.p2452
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Genetic diversity of Soybean Cyst Nematode (Heterodera glycines) populations in Southeastern Goiás state, Brasil

Janaina Alves de Almeida Moreira, Mirian Carvalho Tavares, Fernando Godinho de Araújo*, Ivandilson Pessoa Pinto de Menezes

Agronomy, Escola de Agronomia, Universidade Federal de Goiás, Goiânia, Goiás, Brazil. Zip code: 74.690-900
Agronomy, Instituto Federal Goiano – campus Urutaí, Urutaí, Goiás, Brazil. Zip code: 75.790-000
Genetics and Molecular Biology, Instituto Federal Goiano – campus Urutaí, Urutaí, Goiás, Brazil. Zip code: 75.790-000

Abstract
Heterodera glycines, also known as Soybean Cyst Nematode (SCN), is one of the phytosanitary issues that prevents high soybean yields (Glycine max) due to its dissemination capacity and high physiological race variability. The first step towards the proper and safe use of resistant cultivars lies on correctly identifying the physiological race of this nematode in the crop in order to avoid new breed-selection pressure. Thus, the aim of the present study was to genetically characterize the races of Heterodera glycines populations from soybean-producer counties belonging to the Railroad (Estrada de Ferro) Region (Goiás State, Brazil), as well as to investigate their molecular characterization based on RAPD markers. RAPD data were evaluated in a binary way, in which values (1) and (0) were attributed to the presence and absence of amplified bands for each primer, respectively. The binary matrix was used to estimate the genetic distance between populations, based on the Jaccard dissimilarity index. The clustering analysis was carried out based on the calculated genetic dissimilarity matrix, according to Ward’s method. Eight (8) different physiological Heterodera glycines races were found in the investigated counties. Only 10 out of 28 RAPD primers were polymorphic among SCN populations, whereas the remaining primers either did not amplify, or presented low amplification of the DNA fragment. Five genetically-different groups were recorded among H. glycines population accessions, which presented high genetic variability rate.

Pages 1162-1170 | Full Text PDF|doi: 10.21475/ajcs.20.14.07.p2470
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Vegetative characteristics of soybean (Glycine max L.) as bioindicator parameter of herbicide in the soil

Maria Aparecida Peres-Oliveira, Edna Maria Bonfim-Silva, Tonny José Araújo da Silva, Jefferson Vieira José, Káritta Saldanha Martins, Pedro Alberto Giovanne Engelberg

Federal University of Mato Grosso – UFMT, Institute of Exact and Natural Sciences, Department of Biological Sciences, 5055 Students Avenue Rondonópolis, 78.735-901, Brazil
Federal University of Mato Grosso - UFMT, Institute of Agricultural and Technological Sciences, 5055 Students Avenue Rondonópolis, 78.735-901, Brazil

Abstract
The objective of the present study was to evaluate the presence of the herbicide 2,4-D in the Neosol. We conducted the experiment in a greenhouse using the soybean crop as a bioindicator. A randomized block design with 5 x 3 factorial scheme composed of five application periods before sowing (0, 3, 6, 9, and 12 days) and three simulated rain (0 mm, 20 mm, and 30 mm), with four repetitions was conducted. The herbicide dose was 1500 g a.i. ha-1, the rainfall was simulated one hour after pulverization. Twelve hours after the last rain simulation, Cv. TMG® ANTA 82 RR was sown, and pot moisture remained at 80% of pot capacity throughout the experiment. Herbicide in the soil was evaluated by visual plant phyto-intoxication, plant height, shoot fresh mass and root fresh mass, and shoot dry mass and root dry mass at 26 days after sowing. Statistical analysis was performed according to the polynomial regression model. The application of herbicides in dry soils that remained without rain during the first hours resulted in greater residual effect on the soil (0 mm of rain). The occurrence of higher humidity accelerated the degradation of the herbicide in the soil (30 mm of rain). Longer periods between application and sowing provided more significant increments. The herbicide’s toxic effects reduced linearly as started from 12 days before sowing. The 2,4-D showed low persistence in the soil, and 12 days was observed to represent a safe time length between spraying and sowing, regardless of the occurrence of rainfall. The soybean was a good indicator of 2,4-D.

Pages 1171-1179 | Full Text PDF|doi: 10.21475/ajcs.20.14.07.p2483
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Chemical and microbiological evaluations of Platonia insignis Mart and Theobroma grandiflorum Schum pulps, native fruits from Brazilian Amazon

Patrycia Elen Costa Amorim, José Ribamar Gusmão Araujo, Aline Priscilla Gomes da Silva*, Jéssica dos Santos Almeida, Mariana Oliveira Arruda, Ilka Márcia Ribeiro de Souza Serra, Edna Ursulino Alves, Paulo Alexandre Fernandes Rodrigues de Melo

Center of Agricultural Sciences, State University of Maranhão, São Luís, MA, Brazil
Department of Horticulture, Michigan State University, 1066 Bogue Street, East Lansing, MI 48824, The USA
Federal University of Paraíba, Agricultural Sciences Center, CCA / UFPB, Areia, PB, Brazil

Abstract
The aim of the present study was to evaluate chemical and microbiological parameters of industrialized and artisanal bacuri (Platonia insignis Mart) and cupuaçu (Theobroma grandiflorum Schum) pulps, native Brazilian Amazon fruits. Several fruit pulp brands were selected as follows: industrialized pulps (IP), brands A and B and artisanal pulps (AP), brands C and D. The chemical analyses were based on the determination of initial pH, total titratable acidity (TTA), total soluble solids (TSS) and their ratio (TSS/TTA). Microbiological analyzes quantified mold, yeast, Staphyloccus aureus and Salmonella spp. Their contamination was also determined. Chemical characterization demonstrated that bacuri pulps had lower level of TTA and TSS than cupuaçu pulp. However, ration between TSS and TAA showed higher level in bacuri pulp/brand AP/D. The microbiological analyses showed a ranging from 2.83x105 to 9.35x107 and 7.32x106 to 7.06x107 mold and yeast colony forming units (CFU/g) for bacuri and cupuaçu pulps, respectively. All pulps presented high amounts of Staphylococcus aureus. The presence of Salmonella was verified in industrialized pulp for both bacuri and cupuaçu fruits. We concluded that both industrialized and artisanal bacuri and cupuaçu pulps have poor microbiological food quality, indicating a health threat to the consumers.

Pages 1180-1185 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2559
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Selection of Saccharum spp. rhizobacteria with growth-promoting properties using PCA analysis

Roberta Mendes dos Santos, Everlon Cid Rigobelo*

Post-Graduate Program in Agricultural Microbiology, Faculty of Agrarian and Veterinary Sciences, State University of São Paulo (UNESP), Jaboticabal, Brazil

Abstract
The search for plant growth-promoting rhizobacteria is an ongoing need for the development of new bioinoculants for use in various crops, including sugarcane. Bacterial strains with various plant growth-promoting properties can contribute to sustainable agricultural production. The present study aimed to isolate, characterize and select sugarcane rhizobacteria from six different varieties through principal components analysis. This study selected 167 bacterial strains with the ability to fix nitrogen, produce indolacetic acid, exhibit cellulolytic activity, and solubilize phosphate and potassium were isolated. Of these 167 bacterial strains, seven were selected by principal component analysis and identified as belonging to the genera Staphylococcus, Enterobacter, Bacillus and Achromobacter. Bacillus thuringiensis IP21 presented higher potential for nitrogen fixation and CaPO4 and AlPO4 solubilization and a lower potential for K solubilization in sugarcane. Enterobacter asburiae IP24 was efficient in indolacetic acid production and CaPO4 and FePO4 solubilization and inefficient for Araxá apatite solubilization.

Pages 1186-1194 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2698
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Associations between microorganism and maize plant to remedy mercury-contaminated soil

Letícia Fernanda Lavezzo*, Denise de Lima Dias Delarica, Anne Hélène Fostier, Everlon Cid Rigobelo, Saveetha Kandasamy, George Lazarovits, Camila Chioda de Almeida, Danilo Olandino Souza, Wanderley José de Melo

Department of Soil, São Paulo State University, Jaboticabal, SP, Brazil
Chemistry Institute, State University of Campinas, Campinas, SP, Brazil
Department of Microbiology, São Paulo State University, Jaboticabal, SP, Brazil
A&L Biologicals Agroecology Research Services Center 2136 Jetstream Road London, ON N5V3P5

Abstract
Mercury (Hg) is one of the most toxic metals and is not essential for any organism. In this study, the potential of maize plants in association with bacteria to treat oxisol contaminated with Hg (II) was evaluated. The experiment was conducted in a controlled environment, and pots with 2 kg of oxisol were contaminated with HgCl2 solution at a dose of 36 mg kg-1 of Hg in a 7x4 factorial scheme: control (soil without Hg(II) and microorganisms), T2= (soil with Hg(II) and without microorganisms), and T3= soil with Hg(II) + Enterobacter cloacae, T4= Hg(II) + Bacillus subtilis, T5= Hg(II) + Enterobacter sp., T6= Hg(II) + Staphylococcus epidermidis, and T7= Hg(II) + Bacillus sp. Total Hg quantification was performed by atomic absorption spectrophotometry. At the end of the experiment, the soil pH was significantly lower (0.3 to 0.4 pH unit) in the T2 (no inoculation), Enterobacter cloacae, Enterobacter sp. and Bacillus sp. treatments. Neither contamination of soil with Hg nor plant associations with bacteria led to differences in the root dry mass of maize plants. Maize plants associated with Staphylococcus epidermidis and Bacillus sp. bacteria had lower shoot biomass (71 and 50%) compared to the treatment 2. The best remedial effect was observed with the association of maize plants with Bacillus sp., which recovered 19.67% of Hg(II) in the soil when compared to control and treatment 2 and treatment with B. subtilis. The recommendation is the use of B. subtilis to decrease the toxicity caused by Hg(II).

Pages 1195-1201 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2731
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Effect of reduced spacing on relationship of physiological, morphological and productive traits of corn yield

Luan de Oliveira Nascimento*, Josimar Batista Ferreira, Gleisson de Oliveira Nascimento, Vanderley Borges dos Santos, Clemeson Silva de Souza, Antonia Fabiana Barros de Lima, Francisco Ian de Oliveira Nascimento

Center for Biological and Natural Sciences, Federal University of Acre, Rio Branco CEP: 69920-900, Acre, Brazil
Multidisciplinary Center, Federal University of Acre, Cruzeiro do Sul, CEP: 69980-000, Acre, Brazil

Abstract
Increasing corn grain production without devastating new forest areas is a viable alternative to controlling deforestation. However, increasing plant density in the area may alter plant morphophysiological and productive traits. The objective of this study was to characterize relationships between physiological, morphological and yield traits of corn plants, as well as the cause, effect and relationship of the traits on grain yield. The experiment was carried out in randomized complete block design with four replications. The corn hybrids (2B655PW, AG7088PRO3 and P4285YHR) were grown with row spacing of 40 cm, 60 cm, 80 cm, 95 cm. The evaluated traits physiological were: net photosynthesis (PN), stomatal conductance (Gs), intercellular concentration of CO2 (Ci), leaf transpiration (E), water use efficiency (WUE) and carboxylation efficiency (CE). The morphological were: plant height (PH) and ear insertion height (EIH), stem diameter (SD), and leaf area (LA) and the productive traits were the total number of ear per hectare (NE), number of grains per ear (NGE), grain mass per ear (GME), 100 grain weight (100GW) and grain yield (GY). The characteristics of maize hybrids cultivated in environment with reduced spacing (40cm, 60cm, 80cm, 95cm) of the 2016/2017 crop were investigated through the multicollinearity path analysis. The physiological, morphological and productive traits are considered sources of variation of cause and effect of corn yield in reduced spaced. This traits are essential for observations in maize breeding programs to obtain high yielding varieties in reduced spacing. In conclusion, the physiological (PN, CE, WUE, Ci, Gs), morphological (EIH, SD, LA) and productive (NE, GME) traits provide gains in maize grain yield via indirect selection when the crop is subjected to 40 cm row spacing.

Pages 1202-1208 | Full Text PDF| doi: 10.21475/ajcs.20.14.07.p2630