Australian Journal of Crop Science   AJCS

APRIL 2020 | Early View | 14(04):2020 | DOI: 10.21475/ajcs.20.14.04


Monitoring of drippers during wastewater application through statistical quality control

Flavio Daniel Szekut*, Delfran Batista dos Santos, Carlos Alberto Vieira de Azevedo, Marcio Antonio Vilas Boas, Márcio Roberto Klein, Maycon Diego Ribeiro, Thiago Zuculotto

Federal University of Campina Grande, Academic Unit of Agricultural Engineering, Campina Grande, 58.429-140, Paraíba, Brazil
Federal Institute of Education, Science and Technology of Bahia (IF Baiano), Senhor do Bonfim, Brazil
State University of Western Paraná (UNIOESTE/PGEAGRI), Cascavel, Brazil
Federal University of Paraná (UFPR), Jandaia do Sul, Brazil


Abstract
The use of alternative water sources for irrigation such as wastewaters, promotes innumerous benefits, but investigations must be conducted to minimize the negative effects of this technique. Clogging drippers are of the limitations. This study aimed to monitor the clogging of three models of labyrinth-type drippers subjected to irrigation with wastewater from treated domestic sewage, through statistical quality control using Shewhart charts. The drippers tested were as following: Dripper Streamline 16080 model (Netafim®); Taldrip model (Naadanjain®); and Dripper Tiran 16010 model (Netafim®). The system was installed with five lateral lines per model of dripper on a bench at the field in the Brazilian semi-arid region. The system was evaluated every 36 h of operation at eight collection points in each lateral line, totaling thirty-three evaluations at the end of the experiment, which corresponded to a total of 1188 h of operation. Dripper clogging was identified by the statistical control charts with 432, 540 and 360 h for the drippers Streamline 16080 model, Taldrip model and Tiran 16010 model, respectively, indicating the moment to apply a cleaning process. The monitoring through statistical quality control allowed simultaneously identifying the variability of the process and the reduction in flow rates, identifying the moment of clogging of the system and to carry out actions of unclog.

Pages 551-556 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p1237
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Effects of light, agar, activated charcoal, and culture medium on the germination and early development of Dendrobium seedlings

José Carlos Sorgato*, Jackeline Schultz Soares, Cláudia Roberta Damiani, Luan Marlon Ribeiro

Federal University of Grande Dourados, College of Agrarian Sciences, Dourados, 79.804-970, Mato Grosso do Sul, Brazil
State University of Mato Grosso do Sul, Natural Resources Department, Dourados, 79.804-970, Mato Grosso do Sul, Brazil
Federal University of Grande Dourados, College of Biological and Environmental Sciences, Dourados, 79.804-970, Mato Grosso do Sul, Brazil


Abstract
The objectives of this study were to determine the optimal light conditions, agar concentration, and quantity of activated charcoal in asymbiotic media to improve the in vitro seed germination rate and early seedling development of the epiphytic orchids Dendrobium nobile Lindl. and Dendrobium phalaenopsis Fitzg. Two independent experiments with complete randomized designs were conducted. (1) Treatments were arranged in a split-plot scheme. Seeds in each sub-plot were exposed to one of four light conditions (dark, white fluorescent, red fluorescent + white fluorescent, or red fluorescent) and grown in one of four types of culture media (MS: Murashige and Skoog, ½ MS: half strength MS, K: Knudson C, and VW: Vacin and Went media). (2) Treatments were arranged in a 4 × 5 × 5 factorial scheme (four types of culture media: MS, ½ MS, K, and VW; five concentrations of agar: 0.0, 2.0, 4.0, 6.0, or 8 g L−1; and five concentrations of activated charcoal: 0.0, 1.5, 3.0, 4.5, or 6.0 g L−1). The highest germination rates and early seedling development were observed 45 days after seeding in the presence of white light for D. nobile and red + white light for D. phalaenopsis in MS and ½ MS culture media. Based on the findings of the present study, the use of MS and ½ MS culture media solidified with 4.0–8.0 g L−1 of agar and without activated charcoal is recommended for the optimal propagation of seeds and seedlings of these Dendrobium species.

Pages 557-564 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p1528
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Residues of sweet sorghum promotes suppression of weeds in sugarcane rotation

Paulo Roberto Fidelis Giancotti, Mariluce Pascoína Nepomuceno, Juliana de Souza Rodrigues, Micheli Yamauti, José Valcir Fidelis Martins, Pedro Luís da Costa Aguiar Alves

IFFar (Instituto Federal Farroupilha), Santo Augusto, State of Rio Grande do Sul, Brazil
Universidade Estadual Paulista “Júlio de Mesquita Filho”, Jaboticabal, State of São Paulo, Brazil
Correspondence should be addressed to: Prof. Paulo Roberto Fidelis Giancotti, Federal Institute Farroupilha, Santo Augusto, Rio Grande do Sul, 98590000, Brazil


Abstract
Sorghum is an important crop to plant in rotation with sugarcane. This is mainly because both are inputs for the ethanol industry. Crop residues of sweet sorghum promote suppression of weed re-infestation, avoiding weed interference to the sugarcane crop due to the strong allelopathic potential of sorghum. In order to determine the suppressive effects of sorghum crop residues on weeds, a field experiment was carried out. Seven vegetation covers were used as options for crop rotation with sugarcane. The treatments were sweet sorghum, velvet bean, sunflower, soybean, sugar cane, fallow, and an area without cover. The experiment was randomized blocks with four replications of 27 m2 plots. The weed community of each plot was evaluated by phytosociological indexes at 60 and 120 days after the formation of vegetation cover. The composition of soil seed bank was also evaluated. The weeds with the highest indexes of relative importance during the evaluations were Cyperus rotundus, Raphanus raphanistrum and Parthenium hysterophorus. The diversity of the weed community, estimated by relative importance indexes, was lower in the area with velvet bean as soil cover. Sorghum, velvet bean and sunn hemp covers reduced the soil seed bank compared to the fallow treatment and the treatment without vegetation cover. Crop residues of sweet sorghum and velvet bean provide a decrease in weed infestation in field, and the weed suppression period can last up to 120 days during the dry season.

Pages 565-573 | Full Text PDF | doi: 10.21475/ajcs.20.14.04.p1903
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Effect of bunch protection material and bagging time on the yield of 'Nanica' banana and chilling control

Juliana Domingues Lima*, Eric Watzke Engelking, Danilo Eduardo Rozane, Eduardo Nardini Gomes, Silvia Helena Modenese Gorla da Silva, Ricardo Alfredo Kluge

São Paulo State University, UNESP, Registro, São Paulo, Brazil
University of São Paulo, USP, Department of Biological Sciences, Piracicaba, Brazil


Abstract
The bagging of banana bunch can control chilling injury (CI) in the field, which causes browning of banana peel. The purpose of this study was to evaluate the effect of changing the bunch protection material and bagging time on the yield of 'Nanica' banana (AAA) and the occurrence of CI. The experiment was conducted in Jacupiranga, SP, Brazil. The experimental design was completely randomized design arranged in a 2 x 2 x 6 factorial scheme with eight replicates, two bunch formation periods (autumn-winter and winter-spring), two bagging times (early, before the opening of bracts, and late, after complete opening) and six treatments. Treatments were polyethylene bags with different thickness (blue bags of 3µ in thickness and black bags of 6, 8 and 10µ in thickness combined with white non-woven fabric, black bag of 10µ in thickness combined with blue polyethylene bag 5μ in thickness impregnated with insecticide) and non-bagged banana. The change of sunlight transmission with black polyethylene bags of different thickness promoted a small increase in fruit peel temperature (0.14 to 0.57°C) on colder days (8.72°C), reduced CI index and improved peel brightness (L*) and ho (hue angle), although it did not affect bunch mass. However, in late winter, sunburn increased fruit losses. Sunlight transmission in fruit peel was correlated with CI index (r=0.92*), L* (r =-0.77*) and phenols (r=0.85*). Despite not controlling CI, early bagging is recommended for increasing peel L*.

Pages 574-580 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p1909
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Plant physiological impacts and flavonoid metabolic responses to uptake TiO2 nanoparticles

Kanokporn Sompornpailin*, Wilailack Chayaprasert

College of Nanotechnology, King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10520 Thailand

Abstract
The presence of Titanium dioxide nanoparticles (TiO2 NPs) contamination in the environment is of concern because of their oxidative effect on organisms. Transgenic tobaccos that overexpressed PAP1, a MYB75 gene, were used to investigate the response of plants to the presence of TiO2 NPs and the results were compared to those for wild type (WT) plants. The experiment was performed under tissue culture conditions with daylight fluorescence. The physiological responses of the plants under moderately low concentrations of TiO2 NPs (20–40 mg L-1) were analyzed in relation to metabolic responses and the results were compared to those of plants under zero TiO2 conditions. Under conditions of 20 mg L-1 TiO2, WT and PAP1 plants showed better physiology than plants under other conditions. These plants had higher chlorophyll and carotenoid levels, and better membrane stability than plants under non TiO2 conditions. The WT plants grown in medium at 40 mg L-1 TiO2 showed deteriorated physiology, while PAP1 plants grown under the same condition were shown various changes in physiology depending on the line. Moreover, the content of total soluble sugar (TSS) and flavonoids in the extracts of plant were increased in response to the concentrations of TiO2. However, all PAP1 transgenics had flavone and flavonol contents that were approximately 2–3 times the levels found in WT plants, while TSS and anthocyanin subgroup levels were not different among the WT and transgenic plants. Excessive nanoparticles can induce oxidative damage in cells, and it appears that PAP1 transgenics can alleviate such damage by enhancing flavonoid accumulation.

Pages 581-587 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p1995
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Evaluation of intra-cultivar variability in Olea europaea L. cv. Leccino using morphological, biochemical and molecular markers

Raffaella Petruccelli*, Deborah Beghè, Tommaso Ganino, Giorgio Bartolini, Leonardo Ciaccheri, Rodolfo Bernardi, Mauro Durante

Istituto per la Valorizzazione del Legno e delle Specie Arboree (IVALSA), Consiglio Nazionale delle Ricerche (CNR), Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Italy
Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle Scienze, 27/a, 43124 Parma, Italy
Istituto di Fisica Applicata “Nello Carrara” (IFAC), Consiglio Nazionale delle Ricerche (CNR), Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Italy
Dipartimento di Scienze Agrarie, Alimentari e Agro-ambientali, Università degli Studi di Pisa Via del Borghetto, 80, 56124 Pisa, Italy


Abstract
The phenotypic and genotypic variability of olive tree cv. Leccino (Olea europaea L.), an ancient cultivar from North-Central Italy, was investigated using 44 quantitative and qualitative agro-morphological traits, SDS-PAGE of seed proteins (storage proteins and tegument proteins) and molecular markers such as RAPDs (30 primers) and SSRs (8 primers). Fifteen accessions of Olea europaea catalogued as "Leccino" and one certified tree of "Leccino" (LESt) were examined. The plants were clonally propagated and the measuring of all morphological characteristics was conducted over a period of seven years. The ANOVA analysis showed that all accessions were homogenous for many traits while very few variations were recorded for length of one year old shoots, leaf width, leaf length/leaf width ratio, fruit length, fruit fresh weight, fruit length/fruit width ratio, pit length and pit fresh weight. The PCA analysis and similarity coefficients confirmed a low level of variability of Leccino cultivar. SDS-PAGE analysis of seed proteins showed monomorphic patterns of storage proteins. Protein subunits of teguments revealed a generally high level of similarity as evidenced by Nei-Li coefficient. SSRs and RAPDs markers showed molecular monomorphism among Leccino accessions. The results of agro-morphological, biochemical and molecular nature, taken as a whole, seem to indicate a weakly differentiated/homogeneity of the accessions tested belonging to the Leccino cultivar. The limited morphological and genetic variation could support the assumptions of a monophyletic origin of Leccino cultivar with a genetically restricted base.

Pages 588-596 | Full Text PDF| Supplementary Data PDF | doi: 10.21475/ajcs.20.14.04.p2014
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Assessment of genetic diversity in Thai upland rice varieties using SSR markers

Somrudee Nilthong*, Ekachai Chukeatirote, Rungrote Nilthong

School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand

Abstract
Upland rice (Oryza sativa L.) is precious genetic resource containing some valuable alleles not common in modern germplasm. In this study, genetic diversity and population structure of 98 upland rice varieties from northern part of Thailand were examined using nine simple sequence repeat markers. Number of alleles detected by the above primers was 50 with a minimum and maximum frequency of 2 to 10 alleles per locus, respectively. The polymorphic information content (PIC) values ranged from 0.375 to 0.714 with an average of 0.605 for the primers RM164 and RM1, respectively. Dendrogram cluster analysis of the SSR data distinctly classified all genotypes into three major groups (I, II and III), which corresponded to their places of collection. Population structure divided these genotypes into two distinct subpopulations. Subpopulation 1 consisted of upland rice varieties that collected from Chiang Rai province while the majority of subpopulation 2 were collected from Phayao and Phitsanulok provinces. Analysis of molecular variance revealed 68% variance among two subpopulations and 32% variance within subpopulations, suggesting a high genetic differentiation between the two subpopulations. The huge genetic variability of upland rice in northern part of Thailand can be used to complement the gene pool of modern genotypes in rice breeding program.

Pages 597-604 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2092
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Synchronizing coffee blossoming and fruit ripening in irrigated crops of the Brazilian Cerrado Mineiro Region

Felipe Rodrigues Miranda, Luis Cesar Dias Drumond, Cláudio Pagotto Ronchi*

Department of Management and Conservation of Natural and Agricultural Ecosystems, Agrarian Science Institute, Federal University of Viçosa, Campus Florestal, Florestal, MG, 35690-000, Brazil
Agrarian Science Institute, Federal Universityof Viçosa, Campus Rio Paranaíba, Rio Paranaíba, MG, 38800-000, Brazil


Abstract
Non-uniform blossoming due to deficit irrigation is common in perennial crops such as coffee. It usually leads to uneven ripening of fruits and impairs harvesting efficiency and quality of coffee. The effect of different water deficit periods was evaluated on development stage of flower bud at blossoming stages in coffee plantations. We also evaluated the effect of water deficit on growth, productivity, maturation, and physical quality of the bean. Two identical trials were performed on 19-month-old Coffea arabica cultivars (‘Catuaí Vermelho IAC 144’ and ‘Bourbon Amarelo J9’), from June 2008 to July 2009. Irrigation was suspended and resumed at different times (seven treatments) at the pre-flowering stage using a randomized block design with four replicates. The cultivars reached different levels of deficit for the same period of suspended irrigation. In ‘Catuaí’, 60% of the flower buds opened after the coffee plants were exposed to water deficit from early or late June to early September. In ‘Bourbon’, even the longer water deficit period (06/09 to 09/07) did not induce blossoming greater than 20%. Growth was slightly affected during the water withholding period, but not in the subsequent evaluations in October or January. In both cultivars, drought promoted a higher percentage of ripe cherries at harvest than continuous irrigation, regardless of treatment. In conclusion, although blossoming was not a single concentrated event, especially in ‘Bourbon’, withholding irrigation in the pre-flowering stage contributed to uniform fruit ripening in both Arabica coffee cultivars.

Pages 605-613 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2118
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Designing soil quality and climate assessment tool for sustainable production of signalgrass (Brachiaria brizantha) silvopasture system in mountain ecosystems

Priyono Suryanto*, Eny Faridah, Ananto Triyogo, Dody Kastono, Bambang Suwignyo, Aprilia Ike Nurmalasari, Taufan Alam

Departement of Silviculture, Universitas Gadjah Mada, Yogyakarta, Indonesia
Departement of Agronomy, Universitas Gadjah Mada, Yogyakarta, Indonesia
Departement of Animal Nutrition and Feed Science, Universitas Gadjah Mada, Yogyakarta, Indonesia
Departement of Agrotechnology, Universitas Sebelas Maret, Surakarta, Indonesia


Abstract
Evironmental indicators are the elements required to plan sustainable forest management practices. This assessment was carried out based on indicators that are sensitive to management and changes in the soil, climate, and associated functions. This study aims at determining soil quality and climate that affect the production of signalgrass silvopasture system in mountain ecosystems. The survey-based study was conducted during dry and wet seasons in 2017-2018. We used stratified random sampling method. Stratification was based on site (agroforestry phase) and environment (season and year). Site nested on environment. Agroforestry phases consisted of initial phase (<50% of the shade intensity of the sun), intermediate phase (50-70% of the shade intensity of the sun), and advanced phase (>70% of the shade intensity of the sun). Seasons were divided into two, dry season (rainfall < 60 mm.month-1) and wet season (rainfall > 100 mm.month-1) and years were limited from 2017 to 2018. The observation was conducted on 30 environmental parameters and signalgrass productions. The data was analyzed using linear mixed models, analysis of variance (ANOVA), structural equation modelling (SEM), and stepwise regression. The study results indicate that the highest signalgrass production at the initial agroforestry phase was 4.50 tons.ha-1. There is a very significant decrease in signalgrass production at the intermediate agroforestry phase by 36.64 % and at the advanced agroforestry phase by 280.80 %, compared to the initial agroforestry phase. The signalgrass production was increased very significantly influenced by the increase in cation exchange capacity (CEC), soil organic carbon (SOC), air temperature (Tair), and wind speed (U2). In addition, it was also significantly influenced by available nitrate (NO3-). Signalgrass production can be improved by the assessment tools by improving CEC, NO3-, SOC, U2 , and Tair with routine organic matters application and annual pruning.

Pages 614-621 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2147
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Physiological analysis of papaya seedlings 'Rubi Incaper 511' under different irrigation depths

Vinicius de Souza Oliveira, Stefany Sampaio Silveira, Robson Prucoli Posse, Ana Paula Braido Pinheiro, Karina Tiemi Hassuda, Gleyce Pereira Santos, Jéssica Sayuri Hassuda Santos, Omar Schmildt, Edilson Romais Schmildt

Postgraduate Program in Tropical Agriculture, Federal University of Espírito Santo, São Mateus, ES, Brazil
Federal Institute of Espírito Santo – Campus Itapina, Colatina, Espírito Santo, Brazil
Departament of Agrarian and Biological Sciences, Federal University of Espírito Santo, São Mateus, ES, Brazil


Abstract
One of the main limitations in the process of seedling production is the proper management of irrigation, since this practice implies the costs of orchard implantation. The application of the wrong amount of water leads to water stress in plants causing physiological changes, impairing its development and quality. Thus, the objective of this study was to evaluate the influence of different irrigation slides on the physiological behavior of 'Rubi INCAPER 511' papaya seedlings. The study was conducted during the period from September 9 to November 7, 2016. The experimental design was completely randomized, where the treatments consisted of four different irrigation depth: 8, 10, 12 and 14 mm d-1. Each treatment was composed of 24 plants (repetitions), totaling 96 plants in the experiment. 60 days after planting, plant leaves were evaluated using the following physiological characteristics: total chlorophyll content (SFR-G and SFR_R); flavonoid index (FLAV); anthocyanin index (ANT_RG and ANT_RB) and nitrogen balance (NBI_G and NBI_R). Irrigation depth between 10.96 and 11.03 mmd-1 provided better values for the analyzed characteristics. Therefore, the 11 mmd-1 depth is the most suitable for the production of seedlings, based on the physiological evaluations.

Pages 622-626 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2204
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Dry matter decomposition and potassium cycling in no-till integrated crop-livestock systems: the effects of tree shading and nitrogen fertilization

Flavia Oliveira, Laíse da Silveira Pontes*, Tangriani Simioni Assmann, Betina Raquel Cunha dos Santos, Sandoval Carpinelli, Adriel Ferreira da Fonseca

State University of Ponta Grossa, Av. Carlos Cavalcanti, 4748, CEP 84030-900, Ponta Grossa, PR, Brazil
Agronomic Institute of Paraná, Av. Euzébio de Queirós, s/nº, CP 129, CEP 84001-970, Ponta Grossa, PR, Brazil
Federal University of Paraíba, Rodovia BR 079 - Km 12, CEP 58397-000, Areia, Brazil
Technological Federal University of Paraná, Via do Conhecimento, km 1, CEP 85503-390, Pato Branco, PR, Brazil

Abstract
In integrated crop-livestock systems (ICLS), understanding residue dynamics is crucial to synchronize nutrient release from pasture litter to cash-crop nutrient demands and overcome potential deficiencies using suitable fertilization strategies. The present study evaluated how the inclusion of trees and N availability affected the release rates of K from pasture (black oat + ryegrass) residues to the subsequent maize crop in a no-till ICLS. The experimental design was randomized blocks with treatments set up in split-plots with three replications. Main plots were systems (crop-livestock only and crop-livestock with trees) and sub-plots N levels (90 and 180 kg N ha-1). Litter decomposition and K release from pasture residues were assessed using litterbags, which were installed at maize sowing, for retrieval at 8, 15, 30, 60, 90, 120, 150, and 165 days of incubation. Regardless of N level, shade of 7-year-old trees reduced pasture residue (-30%). Tree residues were unable to offset the shading effect on pasture growth. A faster dry matter decomposition was observed in treeless treatment and with 180 kg N ha-1, with a half-life ranging from 14 to 38 days. Despite no changes in K-release dynamics among treatments, total K released was significantly higher for treeless system (61 kg K ha-1) than in system with trees (40 kg K ha-1), due to changes in the initial amount of residue. These results must be taken into account in fertilization practices. Therefore, a few feasible silvicultural interventions should be considered to avoid losses in soil cover, maximizing nutrient cycling benefits.

Pages 627-632 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2207
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Virulence not linked with vegetative compatibility groups in Australian cotton Verticillium dahliae isolates

Pearl Dadd-Daigle, Karen Kirkby, Damian Collins, Will Cuddy, Peter Lonergan, Sharlene Roser, Piklu Roy Chowdhury, Maurizio Labbate and Toni A. Chapman*

Biosecurity and Food Safety, New South Wales Department Primary Industries, Elizabeth Macarthur Agriculture Institute, Woodbridge Road, Menangle, New South Wales, 2568, Australia
School of Life Sciences, The University of Technology Sydney, Harris Street, Ultimo, New South Wales, 2007, Australia
Biosecurity and Food Safety, New South Wales Department Primary Industries, Kamilaroi Highway, Narrabri, New South Wales, 2390, Australia


Abstract
Verticillium dahliae, the causal agent of Verticillium wilt, is a soil-borne ascomycete that infects numerous agriculturally important crops globally, including cotton. As a billion-dollar industry, cotton is economically important to Australia and the management of disease such as Verticillium wilt is key for the success of the industry. Internationally, defoliating V. dahliae isolates belonging to Vegetative Compatibility Group (VCG) 1A cause severe damage to cotton, while non-defoliating VCG2A isolates result in significantly less disease. However, in Australia, VCG2A is causing more severe damage to crops in the field than the defoliating VCG1A. This study aimed to replicate field observations in controlled greenhouse conditions. We examined and compared disease symptoms on a range of Australian commercial cotton varieties when inoculated with different V. dahliae VCGs. Seedlings were root dipped in conidial suspensions and assessed over seven weeks. The final disease score, disease over time and root length were analysed. Plant mortality resulted from both V. dahliae VCG1A and VCG2A isolates across all cotton varieties used, confirming that there are virulent VCG2A isolates present in Australia. To our knowledge, although virulent on other plant hosts, V. dahliae VCG2A has not previously been reported to be highly virulent in cotton. We infer that virulence cannot be defined solely by VCG in Australian V. dahliae isolates causing disease in cotton.

Pages 633-640 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2208
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Chemical characteristics of soil after application of tannery sludge as fertilizer in the sugarcane plant crop

Alessandro José Marques Santos, Clarice Backes*, Lucas Matheus Rodrigues, Arthur Gabriel Teodoro, Leandro José Grava de Godoy, Danilo Augusto Tomazello, Luiz Fernandes Cardoso Campos, Adriana Aparecida Ribon, Tatiany Arrais Lopes, Roberto Lyra Villas Boas

State University of Goiás – Department of Animal Science, R. da Saudade, 56 – 76100-000 – São Luís de Montes Belos, GO – Brazil; Postgraduate Program: Sustainable Rural Development
São Paulo State University – Department of Agronomy, Av. Nelson Brihi Badur, 430 – 11900-000 – Registro, SP – Brazil
State University of Goiás, São Luís de Montes Belos, Goiás, Brazil
São Paulo State University/FCA – Department of Soils and Environmental Resources, R. José Barbosa de Barros, 1780 – 18610-307 – Botucatu, SP – Brazil


Abstract
The aim of this study was to examine the effects of applying tannery sludge as fertilizer in the sugarcane plant crop and its impact on soil chemical characteristics. The soil in the experimental area was classified as dystrophic red latosol type (Oxisol). The experiment was set up as a randomized-block design with four replicates, with treatments represented by five doses of tannery sludge (0, 4500, 9000, 13500 and 18000 kg ha-1) plus one treatment with inorganic fertilization (90 kg ha-1 N, 180 kg ha-1 P2O5 and 120 kg ha-1 K2O). Soil chemical characteristics and sugarcane nutrition and production traits were evaluated. Tannery sludge application increased the organic matter, Ca, S and Na contents in the soil layers of 0-0.20 and 0.20-0.40 m. Heavy metal contents in the soil were not influenced by the treatments. Tannery sludge showed the potential to supply important macronutrients, especially at the highest doses tested. Tannery sludge doses between 10000 and 16250 kg ha-1 provided the greatest plant height and diameter and the highest number of stalks. The highest sugarcane yield, 149.55 t ha-1, was obtained with the sludge dose of 18000 kg ha-1.

Pages 641-648 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2234
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Nutraceutical coating composition for postharvest conservation of 'Paluma' guava

Kalinny de Araújo Alves*, Railene Hérica Carlos Rocha de Araújo, Agda Malany Forte de Oliveira, Fabricio Alves de Morais, Elny Alves Onias, Albert Einstein Mathias de Medeiros Teodosio, Ana Paula Nunes Ferreira, José Franciraldo de Lima, George Alves Dias

Department of Food Engineering, Federal University of Campina Grande (UFCG), Pombal, Paraíba, Brazil
Academic Unit of Agricultural Sciences, Federal University of Campina Grande (UFCG), Pombal, Paraíba, Brazil
Postgraduate Program in Tropical Horticulture, Federal University of Campina Grande (UFCG), Pombal, Paraíba, Brazil
Department of Agronomy, Federal University of Campina Grande (UFCG), Pombal, Paraíba, Brazil
Department of Agricultural Engineering, Federal University of Campina Grande, Center for Science and Technology, AC University City Campina Grande (UFCG), Campina Grande, Paraíba, Brazil


Abstract
This work assesses the influence of edible coating with nutraceutical properties on post-harvest conservation of guavas 'Paluma'. The experiment comprised of a completely randomized design with four replicates and three fruits per plot. Six treatments were applied combining different concentrations of agar and pomegranate seed oil (PS): T1: 1% agar and 0.1 mL/L PS oil; T2: 2% agar and 0.2 mL L-1 PS oil; T3: 3% agar and 0.3 mL L-1 PS oil; T4: 4% agar and 0.4 mL L-1 oil; T5: 5% agar and 0.5 mL L-1 oil; and T6: control (fruits without coating). After the immersion in treatment solutions, the guavas remained stored in an air-conditioned room for ten days at 10 °C and 40% RH. Fruits without coating (control) ripened faster than coated ones, so the treatments preserved fruit coloration. The treatments T4 and T5 provided the best preservation of peel color, suggesting slower ripening and maintenance of fruit quality, as their colors tended to green and opaque. The firmness of fruits without coating was decreased by 35.15% concerning the coated ones. Treatments T4 and T5 had the lowest loss of fresh mass. On the other hand, T5 showed the lowest soluble solids contents (SS)(13.46%). Titratable acidity (TA), SS/TA ratio, total sugars, and carotenoids were not affected by treatments. The edible coating with 4% of agar plus 0.4 mL L-1 of pomegranate seed oil promoted the best quality traits for the post-harvest preservation of the guavas 'Paluma'.

Pages 649-653 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2264
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Regression models for prediction of leaf area in purple ipe [Tabebuia impetiginosa (Mart.)]

Jéssica Sayuri Hassuda Santos*, Karina Tiemi Hassuda dos Santos, Vinicius de Souza Oliveira, Gleyce Pereira Santos, Luis Fernando Tavares de Menezes, Marcio Paulo Czepak, Antelmo Ralph Falqueto, Elisa Mitsuko Aoyama, Omar Schmildt, Edilson Romais Schmildt

Departament of Agrarian and Biological Sciences, Federal University of Espírito Santo, São Mateus-ES, Brazil
Postgraduate Program in Tropical Agriculture, Federal University of Espírito Santo, São Mateus-ES, Brazil


Abstract
Besides its medicinal and ornamental use, Tabebuia impetiginosa is also very economically important. The achievement of accurate and easy-to-perform tools to determine its leaf area is fundamental for understanding the interaction between the plant and the environment. The objective of this work was to obtain regression equations by using several models that use allometric measurements of the fifth leaflet and to select the most accurate one to determine the leaf area of composite leaves of Tabebuia impetiginosa Mart. in a non-destructive way. By using the dimensions of the fifth leaflet such as - length (LFL in cm), maximum width (WFL in cm) and the product between LFL and WFL (LWFL) of leaf limb, the equations were estimated for linear, quadratic, potential and exponential linear models. The results showed that the determination of leaf area could be performed with excellent precision for leaves of different sizes of this species, using the product of the measurements of length and width of the fifth leaflet. The equation that best expresses the leaf area estimate of the composite leaf of Tabebuia impetiginosa is ELACL = 8.7772 + 2.3840 (LWFL).

Page 654-659 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2291
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Fruit canopy position and harvest date influence on colour and quality of Imperial mandarin (Citrus reticulata Blanco)

Prakash Adhikari, Zora Singh*, Vijay Yadav Tokala, Poe Nandar Kyaw, Bronwyn Walsh

School of Molecular and Life Sciences, Faculty of Science and Engineering, Curtin University, GPO Box U1987, Perth 6845, Western Australia
Centre for Crop and Food Innovation, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and Education, Murdoch University, Perth, Western Australia 6150, Australia
WA Citrus, PO Box 7205, Karawara, 6152 Western Australia


Abstract
Rind colour and taste are important factors influencing consumer acceptance of mandarins (Citrus reticulata Blanco) fruit. In this experiment, the influence of fruit canopy position and harvest date on the fruit rind colour and other quality parameters of Imperial mandarins was investigated. The mandarin fruit were harvested from four different positions in the tree canopy i.e., upper-inner, upper-outer, lower-inner and lower-outer and at three different harvest dates (H1 (five days before commercial harvest date); H2 (commercial harvest date) and H3 (five days after commercial harvest date). The experiment was conducted using a two factors (fruit position and harvest time) factorial randomised block design with four replicates and fifteen fruit per replicate. Rind colour and the quality of Imperial mandarins were significantly affected by the fruit position in the tree canopy, with the fruit harvested from the upper canopy having better rind colour and higher levels of organic acids and sugars compared to other positions. The late harvested (H3) mandarins exhibited the best fruit colour. In conclusion, the Imperial mandarin fruit had better fruit colour as well as quality when harvested from the upper canopy and by delaying the fruit harvest date by five days from the original commercial harvest date.

Pages 660-666 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2304
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In vitro fungitoxic potential of Lippia gracilis (Schauer) essential oil against phytopathogens

Kevison Romulo da Silva França*, Flavia Mota de Figueredo Alves, Tiago Silva Lima, Alda Leaby dos Santos Xavier, Plínio Tércio Medeiros de Azevedo, Ionaly Gomes de Araújo, Lídia Pinheiro da Nóbrega, Yaroslávia Ferreira Paiva, Hailton da Silva Barboza, Antônio Francisco de Mendonça Júnior, Ana Paula Medeiros dos Santos Rodrigues, Tiago Augusto Lima Cardoso

Agroindustrial Systems, Federal University of Campina Grande, Pombal, PB, Brazil
Process Engineering, Federal University of Campina Grande, Campina Grande, PB, Brazil
Rural Federal University of Semiarid, Mossoró, RN, Brazil
Agronomy Department, Rural Federal University of Pernambuco, Recife, PE, Brazil
Agronomy/Plant Protection, Rural Federal University of Semiarid, Mossoró, RN, Brazil
Phytopathology Laboratory, Federal University of Campina Grande, Pombal, PB, Brazil

Abstract
This study evaluates the in vitro effects of Lippia gracilis essential oil on the mycelial growth of phytopathogenic fungi. Experiments were carried out using a completely randomized design to assess the effects of eight treatments. Five replicates were evaluated for each experimental group. The essential oil was incorporated into the potato dextrose culture medium and poured into Petri dishes. Treatments were comprised of different concentrations of the oil (0.0125, 0.025, 0.05, 0.1, and 0.2%), a negative control (0.0%), and two positive controls (commercial fungicides). The plates were inoculated with fungi including Colletotrichum gloeosporioides, C. musae, C. fructicola, C. asianum, Alternaria alternata, A. brassicicola, Fusarium solani, F. oxysporum f. sp. cubense, and Lasiodiplodia theobromae and were incubated for seven days at 27 ± 2°C. The following variables were measured to verify the differences observed among treatments: percentage of mycelial growth inhibition and index of mycelial growth speed. All concentrations of L. gracilis oil inhibited the mycelial growth of the fungal species evaluated. The complete inhibition was observed between concentrations of 0.0125 and 0.1%. Treatment with oil inhibited fungal growth with similar, or even greater, efficiency than commercial fungicides.. We recommend the development of in vivo tests to verify whether L. gracilis essential oil can protect against fungal disease in live plants.

Pages 667-674 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2310
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Losses in the mechanized harvesting of sugarcane as of speed function of two harvester models in Tropical Savanna Environment

Warlles D. Xavier*, Diogo C. Silva, Rommel B. da Costa, Diego O. Ribeiro, Vinicius S. Sousa, João Vitor de S. Silva

Department of Soil, Federal Institute Goiano (IFGoiano), rod. Sul goiana, km 01, Countryside, Zip code 75901-970, Rio Verde, GO, Brazil
Agriculture Sector, Agronomy School, Federal University of Goiás (EA-UFG), av. Esperança, sn, Zip code 74690-900, Goiânia, GO, Brazil
Agronomist engineer, Market Development Consultant – Compass Minerals Plant Nutrition, Zip code 47827-000, Roda Velho, BA, Brazil


Abstract
The aim of this study was to evaluate the losses that occur in the sugarcane crop during the harvesting, based on the performance of two harvester models operated at different displacement speeds. The variety harvested was CTC4, with total productivity of 95.0 Mg ha-1. The experimental design was completely randomized in a 2 x 3 factorial scheme with five replications. The treatments consisted of two harvester models (John Deere 3520 and John Deere CH570), operated in three different displacement speeds (3.0 km h-1, 4.0 km h-1 and 5.0 km h-1) in sugarcane harvesting. The quality indicators that assessed after sugarcane harvesting were the following loss types: stump cane, whole cane, tip cane, loose piece cane, shrapnel cane and total cane loss in Mg ha-1. The increase in displacement speed resulted in lower total losses in sugarcane harvesting. The 3520 harvester was superior to the CH570 at the highest speed tested. The reduction of sugarcane harvesting loss indexes was proportional to the increase of the displacement speeds for the parameters such as stump cane, whole cane, tip cane, loose piece cane and total loss cane for 3520 harvester and stump cane, whole cane and total loss cane for CH570 harvester, showing strong negative correlations (> 0.85).

Pages 675-682 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2338
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Water and nitrogen water use efficiency in forage palm irrigated with salt water in the Neossolo

Patrícia Ferreira da Silva*, Rigoberto Moreira de Matos, José Dantas Neto, Vitória Ediclécia Borges, Thiago Galvão Sobrinho, Semako Ibrahim Bonou, Carlos Alberto Vieira de Azevedo, Vera Lúcia Antunes de Lima, Arsênio Pessoa de Melo Júnior

Federal University of Campina Grande, Academic Unit of Agricultural Engineering, Campina Grande, 58.109- 970, Paraíba, Brazil

Abstract
The objectives were to analyze the water and nitrogen use efficiency by forage palm in different irrigation depths with saline water and nitrogen fertilization levels in the Brazilian semi-arid region. The experiment was conducted under field condition during one year of cultivation (360 days). The experimental design was a complete randomized block and 5 x 5 factorial scheme with five irrigation depths (125, 100, 75, and 25% of ET0) and five levels of nitrogen fertilization (0, 150, 300, 450 and 600 kg ha-1 of N) and three replicates. Irrigation and acceptable nitrogen fertilization resulted in a good water and fertilization management. Water and nitrogen use efficiency of forage palm were higher, when water depths and the nitrogen levels supplied to the soil were increased. The 125% ET0 depth showed a higher efficiency of water and nitrogen use in the forage palm during 360 days of study. In conditions of low nitrogen supply, the efficiency of nitrogen use is directly and indirectly associated with the fresh mass yield; while under high supply, the efficiency of the use of nitrogen is more effective. The use of irrigation and nitrogen fertilization in the semi-arid region is recommended to obtain higher productivity of water and nitrogen from the forage palm.

Pages 683-690 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2404
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Productive characteristics of peanut cultivars fertilized with wood ash

Edna Maria Bonfim-Silva*, Pollyanna Yoko Takenaka, Júlio José Nonato, Salomão Lima Guimarães, Tonny José Araújo da Silva

Institute of Agricultural Sciences and Technology, Federal University of Mato Grosso, Rondonópolis, MT, 78736-900, Brazil
Faculty of Agronomy and Zootechnic, Federal University of Mato Grosso, Cuiabá, MT, 78060-900, Brazil


Abstract
Aiming to assist small farmers, the search for low cost fertilizers and soil acid correctives has intensified. The wood ash waste is an alternative, which can act as fertilizer and corrective. It is also from available materials, which are reuseable with no environmental impact. The objective of this study was to evaluate the effect of wood ash doses (0, 6, 12, 18, 24 and 30 g dm-3) on the productive characteristics of peanut cv. IAC OL3 and IAC 503. The experiment was carried in a complete randomized block in factorial scheme 2x6 with five replications in a greenhouse at the Federal University of Mato Grosso campus of Rondonópolis, MT. The substrate was Cerrado Oxisol to fill 1.5 dm3 pots. The analysis of variance with sequential polynomial regression test was employed. The results showed that incorporation of wood ash to the soil was beneficial to the productive characteristics of peanuts. The dry mass of pods was influenced by wood ash application with higher results found for cultivar IAC 503. To the variables leaf dry mass, root dry mass, number of pods, grains pot-1 and grains yield showed no significant interaction between wood ash and cultivars. This study recommends wood ash doses in the range between 22.34 g dm-3 and 29.78 g dm-3.

Pages 691-696 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2482
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The changes of physical properties in ‘Elsanta’ strawberries from the winter and summer cultivations after vibration tests

Saowapa Chaiwong*, Chris F. H. Bishop

Writtle College, Chelmsford, Essex, United Kingdom CM1 3RR
School of Agro-Industry, Mae Fah Luang University, Chiang Rai, Thailand 57100


Abstract
Strawberries (Fragaria x ananassa Duchesne) cv. ‘Elsanta’ were grown in the greenhouse during the winter and summer seasons of 2014 and 2015. A vibration test of strawberry fruits from these cultivations was carried out at the two frequency levels of 3 Hz and 5 Hz for 150 sec plus a control of no vibration to simulate transport. The physical properties (fruit weight, puncture, compression, electrical conductivity (EC), and respiration rate) and bruise incidence of fruits were determined after the vibration test (day 0) and after storage at 10oC (±1oC) and 70% RH (±5% RH) for 3 days (day 3). A higher average temperature (21 as opposed 25oC) during strawberry growth and development of the summer crop gave a shorter period for harvesting, with a smaller fruit and a softer fruit as compared to a lower average temperature in the winter cultivation (8 to 21oC). The fruit from the summer cultivation when vibrated at a frequency of 5 Hz were observed to have significantly higher for wet bruise (50% of total fruits), electrical conductivity (EC) and respiration rate (63.78 mgCO2/kg.hr), as well as lower firmness values (puncture and compression tests) than other treatments (p≤0.05). The lower vibration level at 3 Hz of the winter strawberries did not affect the percentage of bruise and both firmness values (p>0.05), whilst the EC method could noticeably distinguish the bruise incidence, particularly for a frequency of 5 Hz (p≤0.05). The EC method gave a highly significant correlation with wet bruise (r = 0.854) and severity score (r = -0.499) when compared with either firmness tests (puncture and compression) or respiration rate (p≤0.01). The EC technique is suggested for use as a bruise indicator of strawberries and an application for a bruise assessment for a whole strawberry punnet during postharvest handling operation and transport.

Pages 697-704 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2482
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Application of hemin-induced growth and biochemical modifications in Hassawi okra (Abelmoschus esculentus L.) grown in seawater salinity

Osman Ali Hag El Amin*, Mohamed Abdel Mohsen El-kersh, Mohamed Mahgoub Azooz

Biological Sciences Department, College of Science, P.O. Box 5324 – 31982, King Faisal University, Saudi Arabia
Botany Department, Faculty of Science, University of Khartoum, Khartoum, Sudan
Department of Biochemistry, Faculty of Science, Alexandria University, Alexandria, Egypt
Botany Department, Faculty of Science, South Valley University, 83523 Qena, Egypt


Abstract
The present study investigated the possible protective role of hemin (75 µM) on okra (Abelmoschus esculentus L.) plants grown under diluted seawater (seawater/normal water) in plastic bags on loam soil and compost (1:1). Four levels of seawater were prepared by diluting seawater to give 1.8, 3.6, 5.4 and 7.2 dsm-1. Okra plants were irrigated with these concentrations of seawater. The effects of seawater salinity on okra plants were evaluated by determining growth parameters, superoxide dismutase (SOD) activity, catalase (CAT) activity ascrobate content, α-amylase, protease and lipid peroxidation in the presence or absence of hemin. The study found that seawater salinity resulted in a high level of lipid peroxidation, which was associated with significant decrease in growth parameters and protease activity. The activity of SOD, CAT and ascorbate content were increased significantly, compared to control plants. Alleviation effect of hemin was obvious on growth parameters at most salinity levels. This was associated by enhancement of CAT and α-amylase activities and reduction of lipid peroxidation compared to the corresponding untreated salinized plants. So hemin could play a central function as a signal molecule in salt tolerance of okra plants. The results of this study demonstrated that okra can be grown successfully using diluted seawater and the different antioxidants could partially alleviate the harmful effects of seawater stress that reflected on growth and some physiological changes of okra plant. According to these findings, it can be pronounced that the treatment of salinized okra with hemin (75 µM) may reduce the negative impact of light salinity stress.

Pages 705-711 | Full Text PDF| doi: 10.21475/ajcs.20.14.04.p2413