Australian Journal of Crop Science   AJCS

Genetic variation and trait association of tef [Eragrostis tef (Zucc.) Trotter] evaluated under optimal and moisture stressed environments

Mizan Tesfay Abraha*, Shimelis Hussein, Mark Laing, Kebebew Assefa

University of KwaZulu-Natal, African Centre for Crop Improvement, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa
Tigray Agricultural Research Institute, Axum Agricultural Research Centre, P.O. Box 230, Axum, Ethiopia
Ethiopian Institute of Agricultural Research, Debre-Zeit Agricultural Research Centre, National Tef Research Project, P.O. Box 32, Debre-Zeit, Ethiopia

Abstract
Tef [Eragrostis tef (Zucc.) Trotter] is one of the major cereal crops grown in the Horn of Africa for food and as an export commodity for its unique nutritional qualities. Moisture stress is the leading yield limiting factor of tef production in northern Ethiopia. The objectives of this study were to assess the genetic variability present among 144 tef genotypes of varied population and to identify important agronomic traits with high heritability and correlations for effective breeding. The genotypes were evaluated using four experiments laid down in a 12 x 12 lattice design under moisture stressed and non-stressed conditions in the northern Ethiopia. Main shoot panicle seed weight had high genotypic coefficients of variation (GCV) of 22.4% and 25.9% under non-stressed and stressed conditions, respectively. Grain yield had GCV values of 17.6% and 20.0% in the corresponding environments. Heritability was highest under optimum condition than the moisture stressed, which is valuable to conduct effective selection. A path-coefficient analysis indicated that direct selection for high biomass, harvest index and late maturity could increase grain yield under optimal conditions, while under moisture stress conditions early maturity, high biomass and harvest index were important direct selection criteria for tef breeding aiming for drought tolerance.

Pages 241-247 | Read More| doi: 10.21475/ajcs.17.11.03.pne69
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Association mapping for photosynthesis and yield traits under two moisture conditions and their drought indices in winter bread wheat (Triticum aestivum L.) using SSR markers

Iqbal Saeed, Xiaojie Chen, Daoura Goudia Bachir, Liang Chen, Yin-Gang Hu*

State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, Shaanxi, P.R. China
NIFA, PO Box 446, Tarnab, Peshawar, KP, Pakistan
Henan Key Laboratory of Nucleus Agriculture, Isotope Institute Co Ltd, Henan Academy of Sciences, Zhengzhou 450015, China
Institute of Water Saving Agriculture in Arid Regions of China, Yangling, Shaanxi, 712100, China

Abstract
Net photosynthesis rate and drought resistance in wheat needs to be improved to enhance overall wheat productivity. Association mapping was used to explore the potential QTLs associated with net photosynthesis rate (Pn), thousand-kernel weight (TKW), biomass plant-1 (BMPP) and grain yield plant-1 (GYPP) under two water conditions and their drought indices, i.e. stress tolerance index (STI) and stress susceptibility index (SSI) in wheat using 269 whole-genome SSR markers in 59 winter wheat genotypes. Large numbers of marker-trait associations (MTAs) were detected for photosynthesis and yield related traits under both water conditions and related drought tolerance indices in both seasons. However, the number of significant associations reduced greatly when Bonferroni correction (FPDR) test was applied. Single marker, i.e. Xpsp3123-7D was associated with multiple traits across moisture conditions as well as growth seasons. Xgwm182-5D was stably associated with TKW under water-stressed conditions and with GYPP under well-watered conditions, respectively in both seasons. Xcfd33-6D was consistently linked with BMPP in both seasons under well-watered condition. A Total of 28 associations for the drought tolerance indices of those phenotypic traits qualified FPDR test. Of these, Xpsp3123-7D was consistently associated with the two drought indices of the traits in two seasons. The markersXwmc707-4A and Xgwm182-5D were stably associated with stress susceptibility index (STI) of BMPP and stress tolerance index (STI) of TKW, respectively across two seasons. These putative QTLs, especially Xpsp312-7D can be the key targets to improve photosynthetic efficiency and yield potential of bread wheat in rainfed ecosystem.

Pages 248-257 | Read More| Supplementary Data| doi: 10.21475/ajcs.17.11.03.pne252
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Morphological characterization of indigenous vegetable (Atriplex hortensis L.) from trans-Himalayan region of Ladakh (Jammu and Kashmir), India

Tsewang Rinchen*, Narendra Singh, Samar Bahadur Maurya, Vikas Soni, Manisha Phour and Bhuvnesh Kumar

Defence Institute of High Altitude Research (DIHAR), Leh, Ladakh-194101-Defence Research and Development Organisation (DRDO), India

Abstract
In the present study a total of one hundred thirty two accession of indigenous vegetable (Atriplex hortensis L.) collected from fifteen different Trans-Himalayan geographical regions of Jammu and Kashmir, India, were morphologically characterized for 6 qualitative and 15 quantitative traits following descriptors developed by the National Bureau of Plant Genetic Resource (NBPGR), New Delhi, India, during the year 2014 - 2015. Multivariate analysis, principal component analysis (PCA), multidimensional scaling (MDS) and cluster analysis were performed using morphological traits to determine whether these populations are reliably similar or diverse. The first two principal components encompass more than 60% variation among population. The results of PCA and MDS analysis were comparable to the cluster analysis, which shows considerable phenotypic variation. Study of morphological characteristics of the accessions showed considerable variations which signify rich diversity within populations from different regions of cold desert.

Pages 258-263 | Read More| Supplementary Data| doi: 10.21475/ajcs.17.11.03.pne261
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Effects of biochar on pepperoncini (Capsicum annuum L cv. Stavros) germination and seedling growth in two soil types

A. Liopa-Tsakalidi*, P. E. Barouchas

Technological Educational Institute of Western Greece, Department of Agricultural Technology, Theodoropoulou Terma, 27200 Amaliada, Greece

Abstract
Biochar is a solid material obtained from the carbonization of biomass. The effect of biochar on the germination and seedling growth of pepperoncini pepper (Capsicum annuum L. cv. Stavros) was studied under controlled growth chamber conditions in two experiments. The substrates in the pre-test experiment (first experiment) were 2%, 4%, 6%, 8%, and 10% biochar (at 24°C or 28°C), while in the second experiment they were acidic (pH 6.1) or alkaline soil (pH 7.2), with or without biochar at 24°C. Three replicates (Petri dishes) for each treatment were placed at random in a growth chamber for 12 days at a 16/8h light/dark photoperiod, 12 klx light intensity and 80% relative humidity. In biochar substrates the seed germination percentage in Η2Ο-control was high at 24°C and low at 28°C. At 28°C it was also increased (4°C) and it was higher than the corresponding one in the Η2Ο-control. At both temperatures (24°C and 28°C) there was a tendency for increased height growth. The percentage of seed germination in acidic soil substrates was low (42%), while in alkaline soil substrates high (82%). All biochar applications in acidic soil substrates increased the seed germination percentage, which varied between 53% and 67%. Biochar application in alkaline soils substrates did not influence seed germination. Seedling height in acidic soil substrates was 0.15cm, while in alkaline soil substrates it was 1.63cm. Biochar application in acidic soils increased the seedling height, while in alkaline soils it was reduced when compared to the control.

Pages 264-270 | Read More| doi: 10.21475/ajcs.17.11.03.pne328
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Growth and volume of Myracroduon urundeuva Allemão after ten years of silvicultural interventions

Ana Carolina Freitas Xavier, Carlos de Melo e Silva-Neto*, Thalles Oliveira Martins, Fernanda Gomes Ferreira, Marina Morais Monteiro, Guilherme Murilo de Oliveira, Fábio Venturoli

Federal Technology University of Paraná, Londrina, Paraná, Brazil
Federal Institute of Education, Science and Technology of Goiás (IFG), Goiás City, Goiás, Brazil
University of Brasília, Department of Forest Engineering, Darcy Ribeiro Campus, Zip Code: 04357, Post Code: 70904-970, Asa Norte, Brasilia/DF, Brazil
Federal University of Goiás, Campus Samambaia, Zip Code: 74900-000; Goiânia, Goiás, Brazil

Abstract
The application of low impact silvicultural management techniques encourage the growth of tree species of high commercial value without interfering negatively in natural regeneration. The Myracroduon urundeuva has high mechanical strength, high density and considerable durability, therefore being highly used in construction, woodworking and carpentry, but had an intense and predatory exploration process devastating its natural populations due to its multiple uses The objectives of this study were to evaluate the diametrical increase of Myracroduon urundeuva Allemão adults and assess the influence of competition elimination treatments on the population structure and dynamics. A total of twelve plots of 750 m² were established side by side. The experimental plots were randomly submitted to different treatments after the vegetation survey: (T1) – witness; T2 – removal of woody species within a one-meter radius (1 m) for each individual of Myracrodruon urundeuva with DBH > 9 cm; treatment 3 (T3) – same as T2 plus the removal of vines throughout the plot. A total of 22 individuals were submitted to tree log scaling using the non-destructive method of Huber in October 2014. The relative gains in diameter were higher in treatment 3. Diameter increase was observed in the ten-year period, where the total for the witness treatment is 2.25 cm/year. The treatment T2 had a diameter growth of 0.90 cm/year and T3 of 2.94 cm/year. The hypsometric equation has precision measurements similar to those found in the adjustments of hypsometric equations for natural forests and for isolated species. The volumetric models were of good performance highlighting the Näslund model.

Pages 271-276 | Read More| doi: 10.21475/ajcs.17.11.03.pne360
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Allelopathic potential of Cymbopogon citratus over beggarticks (Bidens sp.) germination

Fábio Henrique Krenchinski*, Leandro Paiola Albrecht, Alfredo Junior Paiola Albrecht, Patrícia Costa Zonetti, Augusto Tessele, Arthur Arrobas Martins Barroso and Henrique Fabricio Placido

Faculty of Agronomic Sciences, Sao Paulo State University, Botucatu, SP, Brazil

Abstract
Allelochemicals are important and innovative tools for weed control as they neither harm the environment nor increase weed management costs. The secondary metabolites can be extracted by water or soaking and later applied in soil or leaves. This study evaluated the leaf extracts of Cymbopogon citratus, affecting germination of Bidens pilosa and B. subalternans seeds. Two trials were conducted in germination chambers. The completely randomized design was employed in both trials with 5 replications. Trial one was arranged in a 2×3 double factorial design, with two periods of leave collection (morning and afternoon); and three extract preparations (aqueous extract by maceration, aqueous extract by infusion and control with distilled water). Trial two was set up in a 2×2×5 triple factorial design, with two extracts (aqueous extract by maceration, aqueous extract by infusion); two time of day collection (morning and afternoon) and five extracts concentrations (0; 25; 50; 75 and 100%). The means were compared by F and Tukey’s test (p ≤ 0.05). To evaluate extracts concentrations a regression analysis was run. The results showed that the aqueous extract by maceration of C. citratus decreased germination and germination speed of Bidens pilosa and Bidens subalternans more than the aqueous extract by infusion, for both species. The concentrations interfered, inversely and proportionally, decreasing germination and germination speed. The germination of beggarticks was affected by the extracts of C. citratus, suggesting further studies for this plant.

Pages 277-283 | Read More| doi: 10.21475/ajcs.17.11.03.pne362
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Response of horticultural crops to application of bioprotector and biological control of Ralstonia wilt in Brazilian Ultisol

Newton Pereira Stamford, Leandro Reis Costa Santos, Adriana Bezerra dos Santos, Kathiane Rodrigues de Souza, Wagner da Silva Oliveira, Emmanuella Vila Nova da Silva

Department of Agronomy, University Federal Rural of Pernambuco, 52.171-900, Recife, Pernambuco, Brazil

Abstract
The production of biofertilizers from rocks is an economic process that increases nutrients for plant nutrition and reduces environmental pollution. The aim of the study was to evaluate the effectiveness of the bioprotector from phosphate and potassium rocks mixed with an earthworm compound inoculated with free-living diazotrophic bacteria (Beijerinckia indica) and fungus containing chitosan (Cunninghamella elegans) on the characteristics of tomatoes, peppers and green peppers inoculated and non-inoculated with the wilt bacteria Ralstonia solanacearum. The fertilization treatments were: bioprotector applied at the 50% recommended rate – RR (NPKP50), 100% RR (NPKP100) and 150% RR (NPKP150); soluble fertilizers applied alone at the recommended rate RR (NPKF100), with antibiotic (NPKF100+ant) and with crustaceous chitosan (NPKF100+C). A control treatment with earthworm compound (20 t ha-1) was used for comparative purposes. The best results for all horticultural plants were obtained with the bioprotector (NPKP) applied at the highest rate (150% RR) and with the soluble fertilizer (NPKF) at the recommended rate for plants not inoculated with Ralstonia solanacearum. With regard to the effect of the bioprotector in the control of Ralstonia solanacearum, a different response for the horticultural crops with peppers revealed normal growth when inoculated with the pathogenic bacteria, and all of the tomato plants with soluble fertilizer alone died after pathogen addition. Soluble fertilizer with the addition of antibiotic and crustaceous chitosan protected green peppers and peppers against R. solanacearum, particularly when using chitosan. The bioprotector (NPKP) appears to be an alternative to soluble fertilizer.

Pages 284-289 | Read More| doi: 10.21475/ajcs.17.11.03.pne363
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Comparison of root xylem structure and hydraulic conductivity of triticale (X Triticosecale Wittmack) genotypes under salt stress

Ehsan Bijanzadeh*

College of Agriculture and Natural Resources of Darab, Shiraz University, Iran

Abstract
To compare the root xylem and hydraulic conductivity of triticale genotypes (Sanabad, Juanillo, and ET-84-5) an experiment was carried out at two concentrations of NaCl (0 and 100 mM), hydroponically. When seedlings had a root length of 25–30 mm, they were transferred to a modified half-strength Hoagland nutrient solution in growth chamber. Then, xylem anatomy, root surface area, hydraulic conductivity, growth rate, and water loss in 14 to 18 days old plants were measured. The xylem anatomy was considered on free-hand cross-sections that were made from 5-10 mm root tips. Root surface area was determined by measuring the length and the radius of the main axis of seminal, adventitious and lateral roots of the 18 days old plants. Under salt, the length of seminal and adventitious roots decreased significantly and ranged from 53±4 to 29±5 mm and 11±1 to 9±2 mm, respectively. In all genotypes, salinity more negatively affected the diameter of central and peripheral metaxylem vessels compared to the number of vessels. The stellar cells in all genotypes were less lignified in adventitious roots and the mature xylem vessels of seminal roots of ET-84-5 and Sanabad had the most lignified walls. In all genotypes, the central metaxylem of seminal roots was less lignified compared to the peripheral metaxylem. Under salinity, the casparian bands could be detected more in the seminal roots as U-shape especially in ET-84-5 and Sanabad. The surface area of seminal root differed among the genotypes from 1.67×10-3 m2 in Juanillo to 1.04×10-3 m2 in Sanabad under salt stress. Juanillo with highest surface area and lowest thickness of lignified cell wall had the highest seminal root hydraulic conductivity (5.32×10-9 m s-1 MPa-1). It could be concluded that at the early growth stages of the triticale genotypes, the root structures of the Juanillo appeared to be more efficient for water uptake via seminal and adventitious roots and this might be attributed to less lignified cell wall of root cell.

Pages 290-295 | Read More| doi: 10.21475/ajcs.17.11.03.p7684
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Photosynthetic pigments content and chloroplast characteristics of tamarind leaves in response to different colored shading nets

Joyce Dória Rodrigues Soares, Gabrielen de Maria Gomes Dias*, Renata Alves Lara Silva, Moacir Pasqual, Claúdia Regina Gontijo Labory, Simone Abreu Asmar, José Darlan Ramos

Department of Agriculture, Federal University of Lavras, Lavras, Minas Gerais State, Brazil
Rural Development Institute, University of Integration of Lusophone African-Brazilian, Redenção, Ceará State, Brazil
Department of Soil Science, Federal University of Lavras, Lavras, Minas Gerais State, Brazil
Institute of Agricultural Sciences, Federal University of Uberlândia, Uberlândia, Minas Gerais State, Brazil

Abstract
The use of coloured shading nets to improve plant development is a technique, which has received considerable recent interest due to positive responses obtained. In this context, photosynthetic pigments content and chloroplast characteristics of tamarind (Tamarindus indica) plants grown under coloured shade nets were examined. Under greenhouse, tamarind seeds were sown in polypropylene trays containing Plantmax® substrate. When the seedlings reached 10 cm long (approximately 60 d old), they were placed inside of structures covered with blue, red, white and black shade nets, with 50% of shading. After 150 d, the leaves were collected and chlorophyll and carotenoids content as well as chloroplast features were assessed. Plants grown under black net showed higher values for chlorophyll a and chlorophyll b content as well as for total chlorophyll and a/b ratio. The black net was also responsible for providing the highest density of chloroplasts and area of starch grains, while the chloroplast area was greater under blue and black nets. These results make the use of black net, a cultivation practice suitable for commercial purposes.

Pages 296-299 | Read More| doi: 10.21475/ajcs.17.11.03.p7906
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Gas exchange and production of sunflower (Helianthus annuus L.) irrigated with water of different salinity, cationic nature and nitrogen doses

José Raimundo de Sousa Júnior, Geovani Soares de Lima*, Hans Raj Gheyi,Vera Lúcia Antunes de Lima, João Batista dos Santos, Jônatas Raulino Marques de Sousa, Guilherme de Freitas Furtado

Federal University of Campina Grande, Academic Unit of Agricultural Engineering,Campina Grande, 58.109-970, Paraíba, Brazil
Federal University of Recôncavo of Bahia, Nucleus of Soil and Water Engineering, Cruz das Almas, 44.380-000, Bahia, Brazil
Federal University of Campina Grande, Academic Unit of Agricultural Science, Pombal, 58.840-000, Paraíba, Brazil
Fellowof CNPq Reseach Productivity, level 1A, Brazil
Fellow of CNPq Research Productivity, level 1D, Brazil

Abstract
This study aimed to evaluate the gas exchanges and production components of sunflower, cv. BRS 324, as a function of irrigation with water of different salinity levels and cationic nature associated with doses of nitrogen (N). The study was conducted in pots adapted as lysimeters, under field conditions, in an eutrophic Grey Argisol of sandy loam texture. The experimental design was randomized blocks, in 5 x 5 factorial scheme, with three replicates, corresponding to five combinations of water salinity and cationic nature - S (S1- Control; S2- NaCl; S3- CaCl2; S4 - KCl and S5 – NaCl+CaCl2+MgCl2) and five N doses (50; 75; 100; 125 and 150 mg of N kg-1 of soil). Irrigation was applied using water with electrical conductivity - ECw of 0.5 dS m-1 for the control (S1) and 5.0 dS m-1for the other treatments (S2; S3; S4 and S5). Gas exchange through stomatal conductance, transpiration, CO2 assimilation rate, internal CO2 concentration and intrinsic water use efficiency were evaluated and the production components were determined by the internal diameter of the capitulum, the phytomass of the capitulum with achenes and dry matter of the capitulum. The gas exchange of sunflower cv. BRS 324 were significantly influenced, being the biggest decrease due to the variation in the ECw when compared with the cationic nature of irrigation water. Among the evaluated cations, potassium promoted the highest value of stomatal conductance and CO2 assimilation rate. Irrigation with saline water negatively affected the production components of sunflower, regardless of the cation present in the irrigation water.

Pages 300-307 | Read More| doi: 10.21475/ajcs.17.11.03.pne441
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Evaluation of yield performance in cowpea genotypes (Vigna unguiculata (L.) Walp.)

Antônio Félix da Costa, Leandro Silva do Vale, Alexandre Bosco de Oliveira*, José Félix de Brito Neto, Wellington Souto Ribeiro, Gleibson Dionizio Cardoso

Agronomic Institute of Pernambuco, Pernambuco, Brazil
Maranhão State University, Maranhão, Brazil
Federal University of Ceará, Ceará, Brazil,
Paraíba State University, Paraíba, Brazil
Brazilian Agricultural Research Corporation, Paraíba, Brazil

Abstract
Nineteen cowpea genotypes from the Germplasm Bank of the Genetic Improvement Program of the Agronomic Institute of Pernambuco, Brazil (IPA) were evaluated in three locations in Northeast of Brazil, featuring edaphoclimatic characteristics of Tropical Savanna (Cerrado) and Caatinga (Semiarid) biomes. The aim of this study was to evaluate genotypes with production potential for these regions. An experimental design of randomised blocks was used, with 19 treatments (genotypes) and four replications. Six characteristics relating to yield components were studied. There was no significant difference in yield between the genotypes under evaluation for the region of Pesqueira, PE or Lajedo, PE, both in Caatinga biome. However, the studied genotypes displayed variations in yield for Balsas, MA, Cerrado region, demonstrating that this growth environment was suitable for the expression of production potential in the genotypes. The differences presented by genotypes for the characteristics under study favour their recommendation, and demonstrate the possibility of their selection for genetic improvement of the species. The average yield of 840.8 kg ha-1 indicates good adaptation by the genotypes for cultivation in tropical savanna region.

Pages 308-312 | Read More| doi: 10.21475/ajcs.17.11.03.pne433
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Development and productivity of maize in response to spatial arrangement under semiarid condition of Northeastern Brazil

Wanderson de Sousa Mendes, Tiago Augusto Drews, João Carlos Medeiros, Jaqueline Dalla Rosa, Adriano Venicius Santana Gualberto, Fábio Mielezrski

Universidade Federal do Piauí, Campus Professora Cinobelina Elvas, 64900-00, Bom Jesus-PI, Brazil

Abstract
This study evaluates the development and productivity of maize plants at different spatial arrangements under rainfed conditions in cerrado-caatinga (savannah) transition zone, where characterised as semiarid. The experimental plan was Randomised Blocks Design (RBD) with four replications. This was 3×3 factorial design with three types of row spacing (0.35 m, 0.50 m, 0.75 m) and three types of population density (50,000, 65,000 plants.ha-1, 80,000 plants.ha-1). The hybrid 30F53YH recommended for the region was used in this experiment. We collected the morphological parameters of five plants in each subplot for six weeks after thinning. Then, productivity data were obtained by weighing harvested grain from two representative lines of each subplot. Furthermore, all data were analysed by performing both statistical tests Tukey (p≤0.05) and Shapiro-Wilk. The best response of maize canopy architecture and productivity was in smaller spacing (0.35 m) with high population density (80,000 plants.ha-1). However, the total productivity index was high in recommended row spacing and population (0.70m and 50,000 plants.ha-1). Thus, smaller row spacing with a higher population (e.g. 80,000 plants.ha-1) can deliver better plant distribution density as a solution for production losses due to drought during maize growth stages.

Pages 313-321 | Read More| doi: 10.21475/ajcs.17.11.03.pne389
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Evaluation of weed flora changes in Portugal in a 10 year basis

Sofia Ramôa*, Pedro Oliveira e Silva, Ilias Travlos, Teresa Vasconcelos, Paulo Forte, João Portugal

Instituto Politécnico de Beja, Escola Superior Agrária, Rua Pedro Soares, Apartado 6158, 7800-908 Beja, Portugal
Universidade de Lisboa, Instituto Superior de Agronomia, Tapada da Ajuda, Apartado 354, 1349- 017 Lisboa, Portugal
Agricultural University of Athens, Faculty of Crop Science, 75, Iera Odos str., GR11855, Athens, Greece

Abstract
The aim of this study was to assess the composition of weed communities starting from a rainfed farming system (1997), to the early period of transformation in agricultural systems with the adoption of irrigation (2007). The assessments were made within a 10-year interval and the floristic surveys were conducted in the same georeferenced plots. In 1997, the surveys were mostly performed in winter cereals (wheat, oat, barley), while in 2007, considering the same georeferenced plots, there were winter cereals and also irrigated olive groves, parcels of fallow, pasture and pine forest. Weed flora was determined by means of relative frequency, abundance and weed infestation degree. The effect of time was also evaluated by applying the methodology of variance analysis on the values of Shannon-Wiener Index. Canonical Correspondence Analysis was used to complement this information only for 2007 to know how the flora was distributed by the different cultures. Our results revealed that in both cases weed flora was of high diversity (229 and 264 species in 1997 and 2007, respectively), with the most representative families being always the same, namely Asteraceae, Poaceae and Fabaceae. The number of weeds that could be of concern for the farmers revealed to be relatively low. Our study confirmed that despite of the intensification of the agricultural production system, biodiversity increased over time. In both years, Lolium rigidum was present at high densities.

Pages 322-328 | Read More| doi: 10.21475/ajcs.17.11.03.pne378
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Morphological variations and relationship among onion germplasm for quantitative and qualitative traits at trans-Himalaya Ladakh, India

Jagdish Singh Arya*, Narendra Singh, Preeti Singh Arya, Anil Kant

Defence Institute of High Altitude Research, Defence Research & Development Organization, C/o 56 APO, Leh-Ladakh (Jammu & Kashmir) India-194 101
Department of Biochemistry, Narendra Dev University of Agriculture and Technology, Kumar Ganj Faizabad (Uttar Pradesh) India-224229
Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat, Solan (H.P.) India

Abstract
In the present work, the variability, interrelationship, and divergence pattern of twenty six accessions of onion at high altitude were studied based on quantitative and qualitative traits. Multivariate analysis was used to classify the twenty six onion accessions. Cluster I contained two genotypes, cluster II contained ten genotypes, cluster III contained two and cluster IV contained twelve genotypes. The highest inter-cluster distance was observed between I and IV, and the lowest between I and II. The maximum intra-cluster distance was observed in Cluster II and the minimum in cluster III. The intra-cluster distance in all the four clusters was relatively low, indicating that genotypes within the same cluster were closely related. Based on cluster means, cluster 1 is the best in terms of number of leaves and neck thickness, cluster II best in terms of leaf width, Double/deformed bulb, Polar diameter, equatorial diameter, average bulb weight and bulb yield kg/plot, cluster III is the best in terms of days to maturity, TSS and dry matter content and cluster IV which is best in terms of plant height, leaf length and chlorophyll content. Considering cluster distance and cluster mean, the intra cluster distance revealed that the genotypes from the cluster II and genotypes from the cluster IV may be selected as parents for future breeding program. It was found that, PCA extracted three PCs and contributed 95.61 % of the variation out of which PC1 accounted 77.52 % variability, PC2 for 10.72 % and PC3 7.38 % variability of the variance among 26 accessions. The greater part of the variance was accounted for by other traits such as average bulb weight, bulb yield, leaf length, equatorial diameter and TSS. The high diversity found in the accessions shows great potential for improving qualitative as well as quantitative traits in onion.

Pages 329-337 | Read More| Supplementary Data| doi: 10.21475/ajcs.17.11.03.pne369
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Quality of pelleted and bare lettuce seeds at different temperatures

Alan Mario Zuffo*, Everton Vinicius Zambiazzi, Maria Laene Moreira de Carvalho, Natália Trajano de Oliveira, Adriano Teodoro Bruzi, Igor Oliveri Soares, Jéssica Gentil Lima, Heloisa Oliveira dos Santos

Department of Crop Production, State University of Mato Grosso do Sul, 79540-000, Cassilândia, Mato Grosso do Sul, Brazil
Department of Agriculture, Federal University of Lavras, 37200-000, Lavras, MG, Brazil

Abstract
Two lettuce cultivars (Everglades and Virginia) were used to evaluate the performance of pelleted and bare seeds of lettuce under different germination temperatures. A completely randomized 2 x 2 x 5 factorial design was used. The factors consisted of two cultivars with pelleted and bare seeds, five intervals of germination temperatures (17 to 19ºC, 21 to 23°C, 25 to 28°C, 30 to 32°C, 34 to 38°C), with four replications. The first germination count, T50, germination, germination speed index, emergence, emergence speed index and dry mass of plants were evaluated. Sowing germination test was carried out on two sheets of blotting-paper, moistened with water at a ratio of 2.5 times the paper weight in ‘gerbox’ plastic boxes. The boxes with seeds were kept in a thermogradient table, with alternating light procedure: 12 hours of darkness and 12 hours of light. The temperature was regulated to a gradient according to each treatment. On the 4th day, first germination count and germination test were performed. On the 7th day, germination was evaluated with normal seedlings as a parameter. The cultivar Everglades showed a higher germination, especially with pelleted seeds. The germination performance of the cultivars is influenced by the use of bare or pelleted seeds and by temperature. Better seed quality and early growth of lettuce are observed in temperatures between 17 to 23°C.

Pages 338-342 | Read More| doi: 10.21475/ajcs.17.11.03.pne352
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Chenopodium quinoa Willd. A new cash crop halophyte for saline regions of Egypt

Sayed S. Eisa, M.A. Eid, E.H. Abd El-Samad, S.A. Hussin, A.A. Abdel-Ati, N.E. El-Bordeny, S.H. Ali, Hanan M.A. Al-Sayed, M.E. Lotfy, A.M. Masoud, A.M. El-Naggar, M. Ebrahim

Faculty of Agriculture, Ain Shams University, P.O. Box 68, Hadayek Shoubra, 11241, Shoubra El-Kheima, Cairo, Egypt
Vegetable Crop Research Deptartment, Agricultural & Biological Research Division, National Research Centre, 33 El-Buhouth St., 12622, Dokki, Giza, Egypt
Plant Production Department, Ecology & Dry Land Agriculture Division, Desert Research Center, Cairo, Egypt

Abstract
A prerequisite for sustainable saline agriculture of cash crop halophytes in salt affected areas implies exact knowledge of their limits of salinity resistance. Hence, the first part of this study was carried out in pot experiment under greenhouse conditions to evaluate growth and seed yield of C. quinoa Willd. cv. Hualhuas to varying water salinity levels (0, 100, 200, 300, 400 and 500 mM NaCl). The limit of salinity resistance was estimated at 200 mM NaCl (~20 dSm-1) based on seed yield production. Depending on the results obtained from pot experiment, field trials were conducted in saline soil location (ECe 17.9 dSm-1) and in non-saline soil location (ECe 1.9 dSm-1). Seed yield significantly decreased under saline soil by about 61.7%. Beside quantity, soil salinity led to reduce the percentage of moisture, total carbohydrate and total fat contents in seeds. Salinity did not significantly alter the protein content in quinoa seeds. Significant increases in the content of ash and fiber were detected in response to high soil salinity. The higher ash content in seeds under saline conditions was due to the increase of Na+ as well as K+, P3- and Fe++ concentrations. By contrast, soil salinity led to significant decrease of Ca++ and Zn++ contents in seed. Energy dispersive X-ray microanalysis showed that most of Na+ in the seeds produced at saline soil was mainly accumulated in the pericarp followed by embryo tissues, while, the interior reserving tissue (perisperm) exhibiting comparatively low concentration. Increasing most of essential minerals, especially Fe, in quinoa seeds produced under high saline conditions given quinoa a distinctive value for human consumption. Quinoa can be grown and yielded successfully in salt-affected soils (ECe 17.9 dSm-1), where, most if not all of traditional crops cannot grow, although the yield was reduced however, the seed quality was not highly affected.

Pages 343-351 | Read More| doi: 10.21475/ajcs.17.11.03.pne316
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Effects of nitrogen fertilization on yield components in a corn-palisadegrass intercropping system

Rodrigo Estevam Munhoz de Almeida*, José Laércio Favarin, Rafael Otto, Clovis Pierozan Junior, Silas Maciel de Oliveira, Tiago Tezotto, Bruno Cocco Lago

Embrapa Pesca e Aquicultura - Quadra 104 Sul, Av. LO 1, Nº 34, Conjunto 4. CEP 77020-02. Palmas, TO, Brasil
Departamento de Produção Vegetal. Escola Superior de Agricultura “Luiz de Queiroz” (ESALQ-USP). Av. Padua Dias, 11. CEP 13418-900, Piracicaba,SP, Brazil
Departamento de Ciência do Solo. Escola Superior de Agricultura “Luiz de Queiroz” (ESALQ/USP). Av. Padua Dias, 11. CEP 13418-900. Piracicaba, SP, Brazil

Abstract
Pasture and grain crop intercropping is considered an alternative for increasing biomass production during the winter periods in Brazil for the establishment of no-tillage systems. We studied nitrogen (N) fertilization rates in a corn-palisadegrass intercropping system that would allow both corn and biomass production without a reduction in corn yield. A field trial was carried out in São Desidério, Bahia - Brazil using a complete block experimental design with a 5 x 2 factorial layout with two factors: N rate (control, 50, 100, 150, and 200 kg ha-1 N) and two cropping systems (corn with or without palisadegrass). Both corn and palisadegrass were sown simultaneously with N fertilizer applied at sowing. The measurements included corn biomass, grain yield and N uptake. In addition, palisadegrass biomass was assessed at corn harvest and at three consecutive times during the winter. There was an interaction between N rates and the intercropping system. Grain yield was affected by intercropping when N fertilizer rates were lower than 100 kg ha-1, but above that rate, corn grain yield reached 10,000 kg ha-1 and was similar with or without palisadegrass. Nitrogen fertilizers also positively affected corn N uptake. There was no residual effect of N fertilization on palisadegrass biomass production during the sampling periods. However, the biomass of the palisadegrass increased during the winter period and reached 5,000 kg ha-1 of dry matter by the following season. There was no corn yield reduction when corn was intercropped with palisadegrass using nitrogen rates above 100 kg ha-1. In addition, it is possible to increase biomass production for the establishment of no-tillage systems in Brazil.

Pages 352-359 | Read More| doi: 10.21475/ajcs.17.11.03.pne273
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Control of wheat stink bugs (Hemiptera: Pentatomidae) in southern Brazil using the fungus Metarhizium anisopliae

Martin Zanchett Groth, Cristiano Bellé*, Gustavo Zimmer, Maruan Zanchett Groth, Tiago Edu Kaspary, João Roberto Pimentel, Igor Gustavo Oliveira, Vitor Mateus Kolesny, Paulo Dejalma Zimmer

Universidade Federal de Pelotas, Faculdade de Agronomia Eliseu Maciel, Programa de Pós-Graduação em Ciência e Tecnologia de Sementes. Campus Capão do Leão s/n, 96001-970 Pelotas, Rio Grande do Sul, Brasil
Universidade Federal de Pelotas, Faculdade de Agronomia Eliseu Maciel, Programa de Pós-Graduação em Fitossanidade. Campus Capão do Leão s/n, 96001-970 Pelotas, Rio Grande do Sul, Brasil
Universidade Federal do Rio Grande do Sul, Programa de Pós-Graduação em Fitotecnia, 91540-000 Porto Alegre, Rio Grande do Sul, Brasil

Abstract
Stink bugs of the species Nezara viridula and Dichelops melacanthus are considered as some of the main insect pests associated with wheat production in Brazil. The use of the entomopathogenic fungus Metarhizium anisopliae might be an alternative for the management of these insects with chemical insecticides. Thus, the aim of this study was to evaluate and ascertain the pathogenicity of different isolates of M. anisopliae on N. viridula and D. melacanthus adults under laboratory and greenhouse conditions. In the laboratory, the fungal isolates 05RA, 11RA, 08RA, and 02RA, which were collected in the field from adults of N. viridula and D. melacanthus infected with M. anisopliae, were highly pathogenic, leading to 100% mortality in adults of N. viridula and D. melacanthus at 8 days after application (DAA). However, the isolate 08RA presented higher pathogenicity in a shorter period of time for N. viridula (mean mortality time “MMT” = 2.8 days) and D. melacanthus (MMT = 4.0 days) than the remaining isolates. At the greenhouse, the isolate 08RA led to a mortality of 44.9% (N. viridula) and 35.7% (D. melacanthus) at eight DAA; however, the mortality was 100% for both species at 14 DAA, with an MMT of 8 and 10 days for N. viridula and D. melacanthus, respectively. The fungus M. anisopliae constitutes a promising alternative agent to control the growth of adult populations of N. viridula and D. melacanthus in wheat cultures.

Pages 360-366 | Read More| doi: 10.21475/ajcs.17.11.03.pne219

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