November 2017 | 11(11) 2017 | doi: 10.21475/ajcs.17.11.11

November 2017 | 11(11)2017 | doi: 10.21475/ajcs.17.11.11

Productivity of maize by leaf application of zinc (Zn) and copper (Cu)

Luiz Henrique da Silveira Valcarenghi, Alfredo José Alves Neto, Tiago Madalosso, Fernando Fávero, Carlos Alberto Scapim, Leandro Rampim, Jéssica Caroline Coppo, Bruna Broti Rissato, Eloisa Lorenzetti, Giovana Ritter

West of Paraná State University – UNIOESTE, Campus Marechal Cândido Rondon, Street Pernambuco, 1777, Postal Code 1008, Centro, CEP: 85960-000, Marechal Cândido Rondon, Paraná State, Brazil

Copacol-Agroindustrial Cooperative Consolota Ltda, CEP: 85415-000 Cafelândia, Paraná State, Brazil

State University of Maringá - UEM, Agronomy Department, Av. Colombo, 5790. Zona 07. CEP: 87020900 – Maringá, Paraná State, Brazil

State University of Centro-Oeste - UNICENTRO, campus CEDETEG, Agronomy Department, Guarapuava, Paraná State, Brazil

Abstract

The frequent use of the similar formulated fertilizers has reduced the supply of micronutrients to the crops. The application of micronutrients through leaf has increased the crops productivity. In this context, this study aimed to assess the effects of copper and zinc micronutrient applications in biometric variables and grain yield of maize crop. The experiment was conducted at the Agricultural Research Center of Copacol, using copper phosphite and zinc phosphite, using treatment (1) 100 g.ha-1 of copper, treatment (2) 500 g.ha-1 of zinc, treatment (3) 100 g.ha-1 of copper + 500 g.ha-1 of zinc and the treatment (4) witness (control). The treatments were applied at V6 phenological stage of maize with costal pump. The experimental design was randomized blocks with six repetitions. The variables measured were: number of plants per plot, number of spikes per plot, number of rows per spikes, number of grains per row and number of grains per spike, thousand grains weight and productivity of grains. For thousand-grain weight, there was higher effect of micronutrient treatments, compared to the control. For number of grains per row, there was no significant effect. However, application of single Zn showed better effects than Zn+Cu. In conclusion, application of Zn via leaf increased productivity. The Zn increased productivity of maize even when used in the soil with high Zn content.

Pages 1381-1385 | Read More| doi: 10.21475/ajcs.17.11.11.pne291

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Expansion of palm oil (Elaeis guineensis Jacq.) in the state of Maranhão and soil water deficit limitations in the Brazilian Amazon

Lucieta Guerreiro Martorano*, José Reinaldo da Silva Cabral de Moraes, Leila Sheila Silva Lisboa, Rui Alberto Gomes Junior, Victor Proença do Amaral, Lucas Eduardo de Oliveira Aparecido

Embrapa Eastern Amazon, Belém, Pará, Brazil São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal, Department of Exact Sciences

ESALQ/CENA, Piracicaba, São Paulo, Brazil

Federal Rural University of the Amazon, Belém, PA, Brazil

Abstract

Oil palm is considered the crop with the highest oil production per planted area unit. This condition has driven the Brazilian government to create the Sustainable Oil Palm Production Program. Since 2009, the agroenergy production chain has used oil palm as a viable and profitable crop to recover deforested areas in the Amazon. The aim of this study was to assess hydric conditions able to indicate the potential to expand oil palm crops in the state of Maranhão, even in the Legal Amazon. The climate database used (average and extreme temperature in degrees Celsius; rainfall values; relative humidity, and vapour-pressure deficit). Water deficit values were was obtained by comparing the potential evapotranspiration of oil palm (ETc) to actual rainfall (ER). Water balance was calculated based on available water capacity of 125 mm.month-1. Evapotranspiration was obtained using the methodology according to the climate database available to calculate the evapotranspiration rate in an area planted with oil palm in this study. The water deficit values show no restriction in the soil water replacement between January and June. However, from July to December, the water deficit varies between 200 and 300 mm. The levels showed that, in the areas evaluated, oil palm crops will require irrigation. In this period, yield was estimated at 17 tons ha-1 when the water deficit was considered at 210 mm and 14 tons ha-1 for a deficit of 380 mm. This result reinforces that oil palm production may drop by more than 50% due to water deficits and the crop will greatly impact the economy and the environment if the irrigation strategy is adopted in the areas of Maranhão.

Pages 1386-1391 | Read More| doi: 10.21475/ajcs.17.11.11.pne439

Assessment of the genetic diversity of dessert watermelon (Citrullus lanatus var. lanatus) landrace collections of South Africa using SSR markers

Jacob Mashilo*, Hussein Shimelis, Alfred Odindo, Beyene Amelework

University of KwaZulu-Natal, Crop Science Discipline, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa

University of KwaZulu-Natal, African Centre for Crop Improvement (ACCI), Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa

Abstract

Dessert watermelon landraces could provide useful germplasm sources for commercial watermelon breeding and/or conservation. This study assessed the genetic diversity present among dessert watermelon landrace collections of South Africa using simple sequence repeat (SSR) markers. Thirty one diverse dessert watermelon landraces were genotyped using 10 polymorphic SSR markers. A total of 94 alleles were amplified among the sampled population. The number of alleles ranged from 2 to 19 with a mean of 9.4 per locus. The number of effective alleles ranged from 1.07 to 9.94 with a mean of 4.61. Observed heterozygosity values ranged from 0.07 to 1.00 with a mean of 0.53. Expected heterozygosity, which measures gene diversity, was 0.66; which partitioned 75, 25 and 0% of the variation within individuals, among individuals and between populations, respectively. The mean gene fixation was 0.18 suggesting high levels of heterozygosity among the collections. The mean polymorphic information content (PIC) of the SSR loci was 0.65 suggesting their value in genetic diversity analysis of watermelon. The collections were allocated into three genetic groups using cluster analysis. The results revealed the presence of genetic diversity among South African dessert watermelon collections. Genetically unique landraces such as SWM-39, SWM-01, SWM-04, SWM-27, SWM-24, SWM-10 and SWM-36 from cluster I; SWM-35, SWM-21, SWM-02, SWM-34, SWM-07 and SWM-31 from cluster II; and SWM-22 and SWM-18 from cluster III were selected based on their high dissimilarity index. These are recommended for further phenotyping using horticultural attributes for effective breeding and strategic conservation.

Pages 1392-1398 | Read More| doi: 10.21475/ajcs.17.11.11.pne461

Improving the sustainability of tobacco cultivation by optimizing nitrogen fertilization

Sifola Maria Isabella*, Raimondi Giampaolo, Maggio Albino

Department of Agricultural Sciences, University of Napoli Federico II, Via Università 100, 80055 Portici (Napoli), Italy

Abstract

Tobacco covers over 4.3 million hectares of agricultural lands in the world and, as other crops, must be grown following sustainability principles. Tobacco Burley type is fertilized worldwide with rates of nitrogen that can be reduced without significant impact on product yield and quality. In this experiment, Burley tobacco (Nicotiana tabacum L.) plants were grown in the field with or without irrigation and fertilized with 0, 120, 240 or 360 kg N ha−1 over two growing seasons. The experimental design was a split-plot, with irrigation treatments in the main plots and doses of N in the sub-plots, with three replications. The elemental plot area was 100 m (10 x 10 m) in both years. The objective was to address N needs based on critical concentrations of N (Nct) and Nitrogen Nutrition Index (NNI), both of which are not available for this crop. Plant dry matter and leaf area were measured during the crop cycle. Specific leaf weight, total N, Nct and NNI were determined. Nct ranged between 2.2 and 4.0% in 2 years. NNI was greater under non-irrigated than irrigated conditions in both years and they generally increased significantly with N fertilization up to 240 kg N ha-1. NNI measured during the rapid growth was positively correlated with yield under irrigated conditions (r = 0.656*). Based on our results, when water is not limiting, the NNI measured at early growth stages could give a useful indication of the effectiveness of fertilization, i.e. the higher the NNI will be in this phase the better will be the response in terms of cured leaves production.

Pages 1399-1405 | Read More| doi: 10.21475/ajcs.17.11.11.pne475

Path analysis of grain yield associated characters in Brazilians wheat genotypes (Triticum aestivum L.)

Ivan Ricardo Carvalho, Maicon Nardino, Diego Nicolau Follmann, Gustavo Henrique Demari, Tiago Olivoto, Alan Junior Pelegrin, Vinícius Jardel Szareski, Mauricio Ferrari, Tiago Corazza da Rosa, Felipe Koch, Geison Rodrigo Aisenberg, Tiago Pedó, Tiago Zanatta Aumonde, Velci Queiróz de Souza

Federal University of Pelotas, CEP 96010-610, Capão do Leão, RS, Brazil

Federal University of Santa MariaCampus de Frederico Westphalen, RS, Brazil

Federal University of Pampa, Dom Pedrito, RS, Brazil

Abstract

The aim of this study was to evaluate the phenotypic interrelation among agronomic characters associated with wheat grain yield of the main Brazilian cultivated genotypes through path analysis in two environments. The tests were conducted in Tenente Portela-RS and Braga-RS. The experimental design was randomized blocks arranged in factorial scheme, 2 locations × 17 genotypes and 3 repetitions. The evaluated characters were plant height, main stem spike mass, tiller spikes mass, main stem spike grains number, tiller spikes grains number, main stem spike grains mass, tiller spikes grains mass, mass of a thousand grains and grain yield. Path analysis was performed for characters associated with grain yield. The results show that main stem spike grains mass, main stem spike grains number, and tiller spikes grains mass have direct effects on grain yield. Larger main stem spike grains mass, main stem spike grains number, and tiller spikes grains mass should be considered for achieving genotypes of high grain yield potential.

Pages 1406-1410 | Read More| doi: 10.21475/ajcs.17.11.11.pne484

Prediction of genetic gains and correlations in corn hybrids for silage

Jocarla Ambrosim Crevelari, Nayara Norrene Lacerda Durães, Laila Cecília Ramos Bendia, Alysson Jalles da Silva, and Messias Gonzaga Pereira

Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego 2000, Parque Califórnia, CEP 28013-602, Campos dos Goytacazes, RJ, Brasil

Universidade Estadual Paulista Júlio de Mesquita Filho, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane s/n, Vila Industrial, CEP 14884900, Jaboticabal, SP, Brasil

Abstract

During the dry season the production of pastures dicreases. Usually, it makes the situation necessary to use corn silage as fibrous fodder source. The aim of this study was to develop corn hybrids for silage production, prioritizing hybrid combinations of the heterotic group ‘DENT’ to better understand the association between the evaluated traits and to optimize the selection process by using selection indices. Nineteen topcross hybrids and five controls were evaluated in a complete randomized block design with four and five replications in the agricultural years of 2013 and 2014. The following traits were evaluated: plant height, first ear height, stem diameter, yield at silage stage, ear yield with and without straw at silage stage, fresh mass yield, and proportion of grains in the fresh mass. The highest coefficients of correlation were obtained between yield and ear yield with straw (r = 0.94**), and between ear yield with straw and fresh mass yield (r = 0.89**). The Mulamba & Mock selection index was used for prediction of genetic gains. For selection of the superior hybrids, the index resulted in higher estimates of predicted gains for yield at silage stage and fresh mass yield, with values of 6.13 and 4.46%, respectively, using weights assigned. The use of selection indices allows simultaneous prediction of gains in the two main traits. Topcross hybrids presented high potential for silage yield in the North and Northwest Regions.

Pages 1411-1417 | Read More| doi: 10.21475/ajcs.17.11.11.pne539

Physical properties of soils under different management systems in the Cerrado region of Brazil

Gisele Carneiro da Silva Teixeira*, Elton Fialho dos Reis, Itamar Rosa Teixeira, Roberto José de Freitas, Fenelon Lourenço de Sousa Santos

State University of Goiás, Campus of Anápolis, 75132-400, Anápolis-GO, Brazil

State University of Goiás, Campus of Ipameri, 75780-000, Ipameri-GO, Brazil

Abstract

The physical properties of a soil can be influenced by management systems, but information on the effects of management systems such as integrated crop-livestock-woods is still incipient and inconclusive. Therefore, this study aimed to evaluate the changes in the physical attributes of Cerrado soil under different management systems. Soil samples were collected and subjected to an experiment with a completely randomized, 5 x 3 factorial design with five replications. The treatments were different management systems (no-tillage, integrated livestock-woods, cultivated pasture, degraded pasture and preserved area - reference), and samples were collected from three soil depths (0-10, 10-20 and 20-30 cm). The following physical soil characteristics were evaluated: density, total porosity and resistance to penetration. Additionally, the organic matter content has previously been determined for the different systems under analysis. The results showed that soils under conservation management involving corn and integrated crop-livestock-woods presented greater soil density but were also less susceptible to compaction, especially the superficial soil layer. The resistance of the soil profile to penetration was lower under conservation management compared to pasture (cultivated or degraded), but it was superior to that of the reference soil. The areas under braquiária ruziziensis pasture or degraded with Urochloa decumbens pasture presented higher resistance to soil penetration.

Pages 1418-1424 | Read More| doi: 10.21475/ajcs.17.11.11.pne541

Variance components and heritability of yield and yield components of wheat under drought-stressed and non-stressed conditions

Learnmore Mwadzingeni*, Hussein Shimelis, Toi John Tsilo

University of KwaZulu-Natal, School of Agricultural, Earth and Environmental Sciences, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa

Agricultural Research Council-Small Grain Institute, Bethlehem 9700, South Africa

Abstract

This study estimated the variance components and heritability of yield and yield related traits of a population of 96 diverse bread wheat genotypes under drought-stressed and non-stressed conditions. The genotypes were evaluated across eight testing environments during the 2014/2015 and 2015/2016 growing seasons using an alpha lattice design with two replications. Combined analysis of variance and variance components were analysed following the General Linear Model (GLM)’s procedure. Results indicated the presence of significant effects of genotypes, seasons, sites, and water regimes and their interactions. From the eight testing conditions, high levels of genotypic variance (σ2g) were estimated for spike length (73%), number of spikelets per spike (44.19%), plant height (51.26%), number of kennels per spike (32.98%), number of days-to-heading (44.24%) and thousand seed weight (22.98%), resulting in high broad-sense heritability estimates of > 0.50. Conversely, genotypic variation was relatively moderate for the number of days to maturity, grain yield and number of productive tillers per plant, contributing to 15.03%, 8.46% and 6.13% of the total variation, respectively. The heritability estimates of the later traits were 20% ≤ H2 < 50% which may limit their selection gains under drought-stressed environments. Further, quantitative trait loci analysis and progeny testing are required to discern the number of genes and associated genetic effect and to pinpoint genomic regions in the tested wheat genetic resources for effective breeding for drought tolerance.

Pages 1425-1430 | Read More| doi: 10.21475/ajcs.17.11.11.pne548

Agronomic characteristics and oil content of Brazilian sunflower hybrdids under different sowing densities

Martios Ecco*, Fabio Duarte Carlos, Paulo Ricardo Lima, Alfredo Richart, Gustavo Ferreira Coelho, Augustinho Borsoi

Pontifical Catholic University of Paraná, PUCPR, Agronomy Course of the School of Life Sciences, Av. Da União 500, Jardim Coopagro, CEP 85902-532, Toledo, Paraná, Brazil

Assis Gurgacz Faculty, FAG, course of agronomy, Av. Das Torres, 500 – FAG Allotment, CEP 85806-095, Cascavel, Paraná, Brazil

Abstract

The sunflower (Helianthus annuus L.) has good productive capacity and the increase in production is possible by using hybrids adapted to the sowing region and an adequate arrangement of plants without losing quality and oil content. The objective of this work was to evaluate two sunflower hybrids cultivated in different sowing densities, observing the influence on the agronomic characteristics and oil content of the cultivation. The experiment was conducted at the experimental field of the Pontifical Catholic University of Paraná, Toledo. The experimental design was randomized blocks in 2 × 4 factorial scheme, with four repetitions consisted of two plant genotypes (BRS324 and M734) and four plant densities (30, 40, 50 and 60 thousand ha-1 plants). The variables analyzed in the field were: plant height, stem diameter, number of leaves, chapter thickness and chapter size. On the other hand, the variables: mass of one thousand sunflower achene, yield and oil content were analyzed at PUCPR laboratory. According to the results obtained, there was interaction between the density of the BRS324 genotype with plant height, stem diameter and mass of a thousand sunflower achene. For the other variables there was a significant difference as a function of the genotype. The cultivar BRS324 produced a better oil content. For plant height and stem diameter, the cultivar showed opposite behavior, possibly due to adaptation in the western region of Paraná. The variable mass of one thousand sunflower achene was decreased due to the increase of the population density for cultivar BRS324.

Pages 1431-1437 | Read More| doi: 10.21475/ajcs.17.11.11.pne555

Productive characteristics of quinoa (Chenopodium quinoa Willd.) under irrigation and potassium fertilization

Vanessa Mendes Rêgo*, Marcio Koetz, Edna Maria Bonfim-Silva, Tonny José Araújo da Silva, Luana Glaup Araújo Dourado

Universidade Federal de Mato Grosso, Departamento de Botânica e Ecologia, IB, CEP 78060-900, Cuiabá, MT, Brasil

Universidade Federal de Mato Grosso, Instituto de Ciências Agrárias e Tecnológicas, CEP 78735-901, Rondonópolis, MT, Brasil

Universidade Federal de Mato Grosso, Faculdade de Agronomia e Zootecnia (FAZ), CEP 78060-900, Cuiabá, MT, Brasil

Abstract

Quinoa (Chenopodium quinoa Willd.) quickly adapts to different climatic conditions; however, low soil fertility conditions and inadequate soil water levels may reduce yield. The objective of this study was to evaluate the effect of irrigation levels and potassium fertilization for quinoa production in the Cerrado Oxisol. The experiment was performed in a greenhouse, located at the Federal University of Mato Grosso (UFMT), Campus of Rondonópolis - Brazil, using soil collected from a Cerrado Oxisol. The experimental design was a randomized complete block design in a 5x5 factorial scheme with four replicates, corresponding to five potassium doses (0, 100, 200, 400 and 600 mg dm-3) and five irrigation levels (50, 75, 100, 125 and 150% of field capacity). The variables of dry mass of shoot, dry mass of roots, water use efficiency, mass of 100 grains, production and number of grains were analyzed. The dry mass of the aerial part and the roots are influenced by the potassium fertilization in the doses between 530 and 600 mg dm-3. All the vegetative and productive characteristics were affected by the treatments. The highest water use efficiency was observed at the potassium (K2O) dose of 375 mg dm-3 and a 50% irrigation level.

Pages 1438-1443 | Read More| doi: 10.21475/ajcs.17.11.11.pne573

Agronomic and economic efficiency of fertilization of broccoli (Brassica oleracea var. Avenger) with boron (B) and poultry litter

Rodrigo Teles Mendes, Rafael Umbelino Bento, Ricardo Felício, João Antônio Gonçalves e Silva, Cleiton Gredson Sabin Benett, Adilson Pelá*

Goiás State University (UEG), Rodovia GO 330, km 241, Anel Viário, Setor Universitário, 75780-000, Ipameri Campus, Goiás, Brazil

Faculty member of the Professional Master's Program in Conservation of Natural Resources of the Federal Institute Cerrado Goiano Campus Urutaí. Urutaí-GO, Brazil

Abstract

The aim of the study was to evaluate the agronomic and economic characteristics of broccoli following the application of boron (B) doses in the transplanting furrow with or without the application of poultry litter. The research was carried out in a Dystrophic Red-Yellow Latosol (Oxisol) from April to July 2015. The experimental design was randomized blocks in a 2 x 5 factorial arrangement, where the first factor was fertilization without or with poultry litter (0 and 10 t ha-1) and the second factor was the B dose (0, 2, 4, 6 and 8 kg ha-1), with three replicates. The broccoli cultivar used was the Avenger hybrid. The analyzed variables were B content in the inflorescence, leaves, and stem; total B content of the shoot; fresh and dry mass of the inflorescence, leaves and stem; inflorescence diameter; total and commercial yields; incidence of hollow stem; and economic aspects of fertilization. The poultry litter, on the average of all doses, increased the foliar B levels and the fresh mass of the broccoli inflorescences and leaves, providing a greater yield and gross revenue. The B levels in the inflorescences and leaves increased with the B dose regardless of fertilization with poultry litter but only increased in the absence of the organic fertilizer in the stems. The profitability index increased with the B dose up to 8 kg ha-1 in both the presence and absence of fertilization with poultry litter, but the more appropriate to farmers was the B dose of 8 kg ha-1 and 10 t ha-1 of poultry litter.

Pages 1444-1450 | Read More| doi: 10.21475/ajcs.17.11.11.pne574

Performances of low frequency rubber tapping system with rainguard in high rainfall area in Myanmar

Zar Ni Zaw*, Sayan Sdoodee, Regis Lacote

Program of Natural Rubber Production, Technology and Management Program, Natural Resources Faculty, Prince of Songkla University, Songkhla 90112, Thailand

CIRAD, UPR Tree Crop-based Systems, HRPP, R&D, Kasetsart University, Bangkok, 10900, Thailand

Abstract

In Myanmar, natural rubber (Hevea brasiliensis) is mainly grown in the southern part of the country, where the rainfall is too high leading to suspension of tapping in the rainy season and intensive tapping after the rainy season. Rubber farmers face problems of uneven distribution of tapping days, low tapper productivity, high tapping cost, and shorter economical lifespan of the trees. Hence, a study was carried out to address the problems by conducting an on-farm experiment to assess performances of low frequency rubber tapping system (LFRTS) with rainguard in the area. Five treatments: (T1) S/2 d2 (no tapping in the rainy season); (T2) S/2 2d3 (no tapping in the rainy season); (T3) S/2 (RG) d2 (tapping with rainguard in the rainy season); (T4) S/2 d3 ET2.5% Pa (1) 3/y (m) (tapping without rainguard in the rainy season); (T5) S/2 (RG) d3 ET2.5% Pa (1) 3/y (m) (tapping with rainguard in the rainy season) were evaluated. The cumulative yield in kilogram per tree of T5 during the study period was comparable to that of T1, while its daily yield in gram per tapping per tree was 23% and 30% higher than that of T1 and T2, respectively. Bark consumption of T5 was 16% and 39% lower than that of T1 and T2, respectively. T5 needed only 67% of tapper requirement by d2 frequency tapping. Tapping costs of T5 were 17% lower than those of conventional tapping system, T1. The study suggested that LFRTS with rainguard could be implemented to address the problems of the farmers in the area.

Pages 1451-1456 | Read More| doi: 10.21475/ajcs.17.11.11.pne593

Growth and quality of Handroanthus impetiginosus (Mart. ex DC.) Mattos seedlings irrigated with saline fish effluent

Tiago de Sousa Leite*, Rômulo Magno Oliveira de Freitas, Narjara Walessa Nogueira, Hugo Ferreira, Moadir de Sousa Leite

Escola Superior de Agricultura “Luiz de Queiroz”/USP, Piracicaba, São Paulo, Brazil

Instituto Federal de Educação, Ciência e Tecnologia Baiano, Valença, Bahia, Brazil

Universidade Federal Rural do Semi-Árido, Mossoró, Rio Grande do Norte, Brazil

Abstract

Reusing wastewater for irrigation purposes is a sustainable approach for crop production in arid and semi-arid regions. Nevertheless, this technique requires further study on the response of plants to this type of water. This work aimed at assessing the growth and quality of Handroanthus impetiginosus (pink lapacho) seedlings irrigated with different concentrations of saline fish effluent. We used a randomized complete block design with four replicates and four plants per replicate. Treatments consisted of irrigation with five solutions containing different percentages of saline fish effluent diluted in tap water (0 [tap water], 25, 50, 75 and 100% fish effluent). At 60 days after transplanting, the effects of irrigation with saline fish effluent on the initial growth of seedlings were assessed based on shoot height, leaf number, stem diameter, shoot height/stem diameter ratio, leaf area, individual leaf area, leaf dry weight, stem dry weight, root dry weight, total dry weight, Dickson quality index, shoot height/shoot dry weight ratio and shoot dry weight/root dry weight ratio. The use of saline fish effluent diluted up to 50% of the irrigation water proved to be a feasible and sustainable practice for producing H. impetiginosus seedlings, with no negative effects on total dry weight and Dickson quality index. However, higher concentrations of this effluent caused a significant reduction in shoot height and leaf area.

Pages 1457-1461 | Read More| doi: 10.21475/ajcs.17.11.11.pne620

Root growth and productivity of conventional and herbicide-tolerant canola in contrasting environments

Tânia Carla Mattioni, Andréia Caverzan, Saimom Sozo, Gilberto Omar Tomm, Geraldo Chavarria*

Faculty of Agronomy and Veterinary Medicine, Agronomy Post-Graduate Program, University of Passo Fundo, Passo Fundo, Brazil

Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo, Brazil

Brazilian Agricultural Research Corporation-Embrapa Wheat, Passo Fundo, Brazil

Abstract

The canola (Brassica napus L. oil variant) is considered as a winter crop alternative in south Brazil. Thus, the aim of this study was to compare the root growth and the productivity components of hybrid grains of conventional and herbicide tolerant canola in different localities. The experiments were conducted in the municipality of Passo Fundo, Rio Grande do Sul state, and Guarapuava, Paraná state, Brazil. The randomized block design with four repelication was used. The genotypes evaluated were: Hyola 61 and H92002 (conventional), Hyola 571 CL and K10050 (imidazolinone-resistant), and Hyola 751 TT (triazine-resistant). In order to evaluate the root system, soil monolith were collected and image analysis measuring the superficial area and the total root volume of the sample in diameter classes, root density and specific surface area were done. The grains productivity components and the number of branches in the plant were measured through the number of siliques in the branches. The productivity of the grains and the thousand grain mass were measured as well. The canola hybrid presented higher root length, surface area and volume in the diameter scale between 1 and 5 mm of density. In addition, there were variations in the growth of roots and grain productivity in different environments, in which imidazolinone-tolerant hybrids presented higher development of the roots, as well as, higher grain productivity in the different environment studied.

Pages 1462-1468 | Read More| doi: 10.21475/ajcs.17.11.11.pne637

Application of silicon sources in yam (Dioscorea spp.) micropropagation

Filipe Almendagna Rodrigues*, Renata Alves Lara Silva Rezende, Joyce Dória Rodrigues Soares, Vantuil Antonio Rodrigues, Moacir Pasqual, Sebastião de Oliveira e Silva

Department of Agriculture, Federal University of Lavras, Lavras, Minas Gerais State, Brazil

Federal University of Recôncavo of Bahia, Cruz das Almas, Bahia State, Brazil

Abstract

The addition of silicon is known to produce satisfactory results in several types of plant cultures. However, there are no reports on the effects of addition of silicon to yam (Dioscorea spp.) micropropagation culture medium. The objective of the present study was to evaluate the effects of different silicon concentrations and sources on the growth characteristics of yam plants cultivated in vitro. Three sources of silicon were tested: potassium silicate, calcium silicate, and sodium silicate, each at concentrations of 0.0, 0.5, 1.0, and 2.0 mg L-1, in all possible combinations. The experimental design was entirely randomized in a 3 × 4 factorial scheme with four replicates and twelve plants per treatment. The 2 mg L-1 sodium silicate supplement yielded the highest number of leaves (7.0) whereas the 1 mg L-1 sodium silicate produced the longest shoots (4.02 cm). Calcium silicate and potassium silicate yielded the highest fresh weight (0.2835 g and 0.2627 g, respectively). Overall, silicon promotes better plant development, with calcium silicate yielding the highest fresh weight. For in vitro yam cultivation, sodium silicate concentrations ranging between 1–2 mg L-1 are ideal.

Pages 1469-1473 | Read More| doi: 10.21475/ajcs.17.11.11.pne685

Nitrogen fixation of Poaceae and Leguminoseae in a green manure experiment in the Brazilian semiarid region

Reginaldo Alves Ferreira Neto, Ana Dolores Santiago de Freitas*, Vanderlise Giongo, Plínio Barbosa Camargo, Rômulo Simões Cezar Menezes, Everardo Valadares de Sá Barretto Sampaio

Universidade Federal de Pernambuco, Av. Prof. Luís Freire, 1000, CEP 50740-540, Cidade Universitária, Recife, PE, Brazil

Universidade Federal Rural de Pernambuco, Av. Dom Manoel de Medeiros, s/n, CEP 52171-900, Dois Irmãos, Recife, PE, Brazil

Empresa Brasileira de Pesquisa Agropecuária, Caixa Postal 23, CEP 56302-970, Petrolina, PE, Brazil

Universidade de São Paulo - Centro de Energia Nuclear na Agricultura , Av. Centenário, 303. CEP 13416-000 Piracicaba, SP, Brazil

Abstract

Mixtures of green manure species such as, planted prior to commercial crops may incorporate more biomass than planting leguminosae alone. The combination of leguminosae and poaceae can fix more nitrogen than poaceae alone as well. Biomass and nitrogen incorporation of three plant treatmens were compared under irrigation condition. In two mixture treatments, the same seven green manure species were planted together but with different seeding proportions. Treatment (1) (low-legume) had 50% the recommended seeding rate of the legume species (jack beans, cowpea and sunn hemp) and 150% the recommended seeding rate of the non-legume species (maize, pearl millet, sorghum and sun flower). The other treatment (2) (high-legume) had opposite proportions. In the third treatment, no green manure plants were sown and weed plants were allowed to grow. The results showed that biomass (9.1 and 8.2 Mg ha-1) and nitrogen accumulation (160 and 161 kg ha-1) did not differ between the low-legume and high-legume treatments, respectively, which were 2.5 times higher than those of the weed treatment (3.3 Mg ha-1 and 58.1 kg ha-1). Despite the higher non-legume biomass proportion and lower nitrogen concentration, the low-legume treatment symbiotically fixed as much N (52 kg ha-1) as the high-legume treatment because sorghum derived more N from the atmosphere (79 %) and maize in the same range as the legume species (37 to 54%). Therefore, sorghum and maize showed higher N endophytic fixation and green manure prior to commercial crops. Moreover, combination of both legume and poaceae species can providing a high input of N and biomass in a short period.

Pages 1474-1480 | Read More| doi: 10.21475/ajcs.17.11.11.pne726

Effect of sowing date and irrigation regimes on yield components, protein and galactomannan content of guar (Cyamopsis Tetragonoloba L.) in Iran climate

Heidar Meftahizade, Yousef Hamidoghli*, Mohammad Hassan Assareh, Majid Javanmard Dakheli

Department of Horticultural Science, University Campus 2, University of Guilan, Rasht, Iran

Department of Horticultural Science, University of Guilan, Rasht, Iran

Research Institute of Forests and Rangelands, Karaj, Iran

Department of Chemical Technologies, Iranian Research Organization for Science and Technology, Iran

Abstract

In this study, the effects of irrigation regimes and sowing dates on growth, yield performance, protein and galactomannans of guar (Cyamopsis tetragonaloba L.) were monitored in Ilam province (latitude 37°8" min and Longitude 47°27"), Iran. A field experiment was conducted for two years during 2015 and 2016, using a split-split plot randomized block design including two sowing date (15th and 30th July), 4 irrigation regimes (once: after sowing, twice: after sowing and flowering, three times: after sowing, flowering and seed formation, and four times: after sowing, flowering, seed formation and before harvesting) and 3 genotypes (RGC1031, RGC 936 and RGC1066) with three replicates. Main seed yield attributes such as protein, and galactomannans content were evaluated. The results showed that late sowing date responded better in higher yield than to the earlier one (15th). There were not observed significant differences among studied genotypes in case of yield components, galactomannan and protein contents traits. According to ANOVA analysis, RGC-1066 with 4 times irrigation was suitable treatment in case of seed yield. Also the highest amount of protein and galactomannans was obtained in the late sowing date. These results indicated that guar can be put as an alternative crop and can be introduced as a new crop for cultivation in Iran climate.

Pages 1481-1487 | Read More| doi: 10.21475/ajcs.17.11.11.pne758

Genetic diversity and population structure of wild Sardinian Myrtle (Myrtus communis L.) genotypes from different microclimatic areas

Sara Melito*, Leonarda Dessena, Luana Sale, Maurizio Mulas

Department of Agriculture, University of Sassari, Sassari, Italy

Department of Nature and Land Sciences, University of Sassari, Sassari, Italy

Abstract

The wild Sardinian Myrtle (Myrtus communis L.) is an aromatic shrub widely spread in the Mediterranean region. Because of the large use of the plant in food and cosmetic industry, a domestication process started from the last decades. Today, the myrtle may be considered as an aromatic crop. In this artificial evolution, the genetic characterization of wild populations is essential to understand the bases of the phenotype variability useful for cultivar selection. The aim of the present study was to explore the genetic diversity and structure of wild myrtle populations within eco-geographical zone of Sardinia, where the specie is still widely abundant. Eighteen populations were sampled randomly by picking 20 individuals from every site. A total of 360 samples were analysed by AFLP markers, by which 150 polymorphic fragments were detected. In total, two well-differentiated genetic groups were identified. Agrometeorological and geographical variables influenced the distribution of the two clusters. A significant different partition of the two groups was observed from South West to North East direction. Moreover, altitude plays a significant role in the genetic distribution: one cluster is predominant at low altitude and the other at medium (P = 0.0014). AMOVA was performed to explore the effect of different environmental factors to the genetic variance. The highest FST value (0.44) was associated to the origin of the sampling site followed by the genetic partition at K = 2 (0.34). A map of myrtle genetic diversity as result of the collection site was described. These findings are relevant for planning collection for future domestication programs.

Pages 1488-1496 | Read More| Read More| doi: 10.21475/ajcs.17.11.11.pne796

Chemical attributes of agricultural soil after the cultivation of cover crops

Daiane Conceição de Sousa, João Carlos Medeiros*, Jaqueline Dalla Rosa, Julian Junio de Jesus Lacerda, Álvaro Luiz Mafra, Wanderson de Sousa Mendes

Federal University of Piauí, Campus Professora Cinobelina Elvas (UFPI/CPCE), 64900-000, Bom Jesus, PI, Brazil

Santa Catarina State University. Av. Luiz de Camões, 2090, 88520-000, Lages, SC, Brazil

Department of Soil Science, Luiz de Queiroz College of Agriculture, University of Sao Paulo, Av. Padua Dias 11, 13418-900, Piracicaba, SP, Brazil

Abstract

The use of cover crops is a strategy to maintain the productive capacity of agricultural soils. The increase of organic carbon content, nutrient cycling and, consequently, the increase in soil fertility are some of the greatest benefits. This study evaluated the chemical attributes of the soil after the use of cover crops species in the Cerrado region of Piaui. The experiment was carried out from January 2015 to July 2016. It was performed in a completely randomized block design with eleven treatments and four replicates. The treatments consisted of six species of Fabaceae, two of Poaceae, two-component intercrops and spontaneous vegetation (control). The soil chemical analyses were performed 14 months after the implantation of the cover crop species. The following soil horizons were evaluated: 0.0-0.10; 0.10-0.20 and 0.20-0.40 m. The values of phosphorus (P), potassium (K+), calcium (Ca2+), magnesium (Mg2+), aluminum (Al3+), potential acidity (H + Al), soil organic carbon (OC), the saturation of bases (V%), saturation by aluminum (m%) and effective CEC were measured. Fifteen months after their establishment, cover crops positively influenced the levels of P, K and OC with no changes in the other chemical properties. The OC contents were higher with the use of C. cajan – cv. ‘fava larga’, brachiaria and C. ochroleuca + millet, mainly in the topsoil. C. espectabilis, spontaneous vegetation, M. aterrima, brachiaria and C. ochroleuca were the most efficient in K cycling.

Pages 1497-1503 | Read More| doi: 10.21475/ajcs.17.11.11.pne799

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