Soil structure after treatment with different operation modes of spading machine

  1. Stoyanov1, K. Trendafilov2, N. Delchev1, G. Tihanov1


1Department of Agricultural Engineering, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria,

2Department of Mechanical Engineering, Faculty of Technics and Technologies – Yambol, Trakia University, 6000 Stara Zagora, Bulgaria


DOI: 10.15547/ast.2018.03.045

(Manuscript received 13 June 2018; accepted for publication 24 August 2018)


Abstract. The article presents the results of a field survey of the work of a spading machine. The influence of the following factors has been investigated: operating speed, deflector cover deflection angle and rotation speed of the power take-off shaft of the tractor on soil crushing. The relative share of aggregates smaller than 1 mm, from 1 to 10 mm, from 10 to 25 mm, from 25 to 50 mm, from 50 to 100 mm and over 100 mm has been determined. Regression relations have been created to determine the proportion of soil fractions of certain sizes depending on the controllable factors. The operating speed and the position of the machine cover have the greatest influence on the granulometric composition of the soil in cultivation with a spading machine. The resulting regression relations can be used to determine the operating parameters of the machine to achieve the desired granulometric composition of the soil depending on the purpose of the cultivation.


The effects of inoculation and N fertilization on soybean [Glycine max (L.) Merrill] seed yield and protein concentration under drought stress

  1. Basal, A. Szabó


Institute of Crop Sciences, Faculty of Agricultural and Food Sciences and Environmental management, Böszörményi út 138, Debrecen, Hungary


DOI: 10.15547/ast.2018.03.044

(Manuscript received 7 June 2018; accepted for publication 8 August 2018)


Abstract. An experiment was conducted during 2017 growing season in Debrecen, Hungary to investigate the effects of inoculation and N fertilization on the seed yield and protein concentration of soybean [Glycine max (L.) Merr.] cultivar (Boglár) under three irrigation regimes: severe drought (SD), moderate drought (MD) and control with no drought stress (ND). Three N fertilizer rates were applied: no N (0N), 35 kg/ha (35N) and 105 kg/ha of N fertilizer (105N). Half of the seeds in each treatment were inoculated with Bradyrhizobium japonicum inoculant. The results showed significant differences in the seed yield associated with both inoculation and irrigation, whereas there were no significant differences in the seed yield associated with fertilization. When seeds were inoculated, yield was increased when (35N) was applied compared to (0N); however, high rate (105N) reduced the yield to a level even less than (0N). When seeds were not inoculated, the highest rate of N increased the yield the most compared to the other two N fertilizer rates under drought. Under severe drought, inoculation was positively and significantly correlated with yield; however, adding N fertilizer increased the yield of non-inoculated plants compared to the inoculated ones, regardless of N-fertilizer rate. Protein concentration in the seeds was significantly affected by irrigation and by fertilization, but not by inoculation. Protein concentration increased as N fertilization rate increased, regardless of inoculation or irrigation; moreover, increasing N rate reduced the correlation coefficient of protein concentration with irrigation. It was concluded that adding N-fertilizer is not always recommended, especially when seeds are inoculated before being sown; however, it is very important under severe drought stress to sustain yield. Enhanced protein concentrations could be achieved by applying N fertilization, whether the seeds were pre-inoculated or not.


Productivity and yield stability at late treatment of durum wheat (Triticum durum Desf.) with antibroadleaved herbicides. I. Influence at treatment during 1-st stem node stage

Gr. Delchev, D. Delchev


Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria


DOI: 10.15547/ast.2018.03.043

(Manuscript received 25 May 2018; accepted for publication 20 July 2018)


Abstract. The research was conducted during 2012 – 2014 on pellic vertisol soil type. Under investigation was Bulgarian durum wheat cultivar Victoria (Triticum durum var. valenciae). A total of 20 antibroadleaved herbicides were investigated: Granstar 75 DF, Granstar super 50 SG, Ally max SG, Arat, Biathlon 4 D, Derby super WG, Mustang 306.25 SC, Weedmaster 646 CL, Sunsac, Secator OD, Logran 60 WG, Lintur 70 WG, Akurat 60 WG, Akurat extra WG, Eagle 75 DF, Herbaflex, Starane 250 EK, Sanafen, Dicotex 400 and Herby 675. All herbicides were treated in 1-st stem node stage of durum wheat. During 1-st stem node stage of durum wheat the antibroadleaved herbicides Arat, Biathlon, Derby super, Mustang, Weedmaster, Secator, Lintur, Akurat, Akurat extra, Eagle, Starane, Sanafen, Dicotex and Herby can be used. These herbicides do not have a negative influence on grain yield. The most unstable are herbicides Granstar, Granstar super, Ally max, Sunsac, Logran, Herbaflex and Herby. Their selectivity to durum wheat is influenced most strongly by weather conditions during the vegetation period. From the viewpoint of technology for durum wheat growing, during 1-st stem node stage technologically the most valuable are herbicide Derby super, Arat, Biathlon, Secator, Akurat, Akurat extra and Lintur. They combine high grain yield with high stability in relation to different years. The herbicides Granstar, Granstar super, Ally max, Sunsac, Logran and Herbaflex cannot be used during 1-st stem node stage of durum wheat.


Yield and seed quality of some soybean (Glycine max. L) varieties, cultivated in Osmaniye region, Turkey

F.F. Aşik, R. Yildiz


Oil Seeds Research Institute, 80950 Osmaniye, Turkey


DOI: 10.15547/ast.2018.03.042

(Manuscript received 21 May 2018; accepted for publication 2 August 2018)


Abstract. This study was carried out to determine yield and seed quality of 14 soybean varieties (Blaze, Ataem-7, Bravo, İlksoy, Çetinbey, Nova, Atakişi, Cinsoy, Adasoy, Umut-2002, Türksoy, Arısoy, HA.16-21 and SA-88), conducted with 3 replicates, according to the Randomized Block Experimental Design in the Osmaniye region, Turkey during 2016 growing season. Plant height, seed number per pod, first pod height, number of branches per plant, number of pods per node, number of pods per plant, harvest index, protein content, oil content, hundred seed weight, seed yield and fatty acid composition were the parameters examined. It was found that the controlled parameters values at different soybean varieties ranged as follows: plant height – between 69.47cm (Blaze) and 101.83cm (HA.16-21); number of seeds per pod – between 1.82 units/pod (Adasoy) and 2.21 units/pod (Blaze); first pod height – between 13.10cm (Blaze) and 22.53 cm (Umut-2002); number of branches per plant – between 1.07 units/plant (HA.16-21) and 3.00 units/plant (Nova); number of pods per node – between 2.43 units/node (Umut-2002) and 4.81 units/node (Adasoy); number of pods per plant – between 27.40 units/plant (Umut-2002) and 47.73 units/plant (Adasoy); Harvest Index values – between 43.99% (HA.16-21) and 54.72% (Ataem) – 55.42% (Blaze); protein content – between 36.09% (Nova) and 39.17% (Çetinbey); oil content – between 15.71% (Blaze) and 19.73% (Türksoy) – 19.82% (Arısoy); 100 seed weight – between 12.54g (Arısoy) and 19.18g (Çetinbey); seed yield – between 2470.41 kg/ha (Arısoy) and 3280.03 kg/ha (Adasoy); acid composition values: palmitic acid – from 9.97% (Türksoy) to 11.47% (Çetinbey); stearic acid – from 3.82% (Ataem-7) to 4.38% (Türksoy); oleic acid – from 22.39% (Bravo) to 28.14% (Çetinbey); linoleic acid – from 47.30% (Çetinbey) to 53.26%  (Ataem-7) and linolenic acid – from 5.49% (Türksoy) to 6.88% (Bravo). The soybean varieties tested showed different advantages over the individual parameters: in terms of seed yield – Adasoy (3280.03 kg/ha) and Atakişi (3260.60 kg/ha) varieties; in terms of protein content – Çetinbey (39.17%) followed by SA-88 (38.55%) genotype; in terms of oil content – Türksoy variety (19.82%) followed by Arisoy (19.73%) variety; in terms of fatty acid composition the results are very diverse.


Profitability analysis of small-scale fish farming in Mubi metropolis of Adamawa State, Nigeria: Alternative to poverty alleviation

J.D. Daniel1, Z.H. Yerima2, A.B. Shelleng1

1Department of Agricultural Economics and Extension, Adamawa State University, Mubi, Nigeria
2Adamawa State Post Primary Schools Management Board, Yola, Nigeria

(Manuscript received 18 March 2018; accepted for publication 28 May 2018)

Abstract. The study examined the profit potentials of fish farming in Mubi, Adamawa State, Nigeria. Data for the study were obtained from 70 respondents through snow-ball sampling technique between April and May 2015. The results revealed 81.43% of the respondents were youth within the age range of 20-40 years, with majority (74.29%) of them being males. About 74.3% had household members, which range from 1-5, more so, 54.3% had one form of formal education or the other. Most of the respondents also (54.30) were civil servants. Analysis of cost and returns from the fish farms unveiled a net farm profit of $407.37 (₦150 879.22) per cycle, with a benefit cost ratio of 2.03, which implies that a dollar is gained as a profit for every one dollar invested in the farming business in the study area. High cost of fingerlings (25.35%) and inadequate information on fish farming practices (15.02%) were among the major problems militating against fish farming in the area. The study recommended the supply of credit facilities to the respondents as well as extension services delivery through government and non-government organisations to improve on the farmers’ output.

Determination of Stone marten (Martes foina) and Pine marten (Martes martes) in natural habitats using camera traps

Department of Animal Production – Non-ruminants and Other Animals, Faculty of Agriculture, Trakia University, Stara Zagora 6000, Bulgaria

(Manuscript received 15 May 2018; accepted for publication 4 June 2018)

Abstract. In the nature, difficulties with distinguishing of closely related species like Stone marten (Martes foina) and Pine marten (Martes martes) appear. Based on 280 photos a non-invasive method for determining the Stone marten and the Pine marten by camera trapping was performed. Sloping trees (similar to Leaning-Pole or Running-Pole) were used as a route for animals to pass with a purpose to be photographed. Honey and distal parts of bird wings were used as a lure. The camera was set to capture the climbing animal from the side. The coat coloration and scent marking patterns – proper species indicators – were clearly visible on daily photos. The night photos showed the differences in body proportion but not these in throat patch coloration. Profile photographing also allowed an individual determination based on throat patch shape and area.

Wastewater characteristics by physico-chemical parameters from different type treatment plants

D. Dermendzhieva

Department of Applied Ecology and Animal Hygiene, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 21 January 2018; accepted for publication 2 April 2018)

Abstract. The purpose of the present study was to make wastewater characterization by physico-chemical parameters from two wastewater treatment plants (WWTPs) – Municipal WWTP (MWWTP) and Poultry meat processing enterprise WWTP (PMPEWWTP). The investigation was carried out during 2016 and 11 wastewater parameters (ToC, pH, EC, SS, COD, BOD and total forms of N, P, K, Na and chlorides content) were controlled in 4 monitoring points (MPs) at both WWTPs: MP-1 – inlet of WWTP, MP-2 – after section of biological treatment, MP-3 – outlet of vertical precipitators and MP-4 – outlet of WWTP. Wastewater samples were collected every two months from each MP and were analyzed by validated Bulgarian State and ISO standards. The following were recorded: a) the value limit variation at the surveyed parameters and their characteristics by monitoring points in both treatment plants; b) that both TPs demonstrated high removal efficiency (81.6-98.6%) in regard to SS, COD, BOD5, Total N and Total P, and very low removal efficiency in regard to Total K (2.2-12.5%); c) that the final effluents from both TPs meet the ecological requirements for discharge in the receiving water bodies (Bedecka River and Azmaka River, respectively) for the parameters SS, COD, BOD5 and TN and deviate from them by phosphorus content that exceeds the permitted limit; d) that in MWWTP there are 25 correlations (15 positive and 10 negative) between monitored WW parameters and in PMPEWWTP – 28 correlations (19 positive and 9 negative), respectively; e) that there are different trends in the changes of the controlled physicochemical parameters by monitoring points and by months in both WWTPs determined on the basis of a regression model – a polynomial of degree II; f) that Na, Cl, COD and BOD5 WW content correlates very well with some other parameters, which allowed the development of linear regression models to determine their concentrations.

Effect of bioorganic fertilizers and growth regulators on productivity and immune response of field tomatoes

O. Georgieva¹, N. Valchev²

¹Maritsa Vegetable Crops Research Institute, 32 Brezovsko shosse, 4003 Plovdiv, Bulgaria
²Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 16 February 2018; accepted for publication 21 May 2018)

Abstract. In conditions of growing tomatoes in the open field the effect of bioorganic fertilizers and growth regulators have been studied based on humic acids Nagro and Stimix on the main growth indicators, yield and immune response of plant in tomatoes for medium early production of the variety Milyana. It has been found that seed treatment and seedlings with the bioorganic products Nagro and Stimix improve the biometric indicators of seedlings and plants during vegetation and accelerate the process of flowering of tomato phenophases. Fertilization with those bioorganic fertilizers at phase flowering increases the earliest and total yield. The application of the technological complex of activities including fertilization with mineral fertilizers Nı6P20K22, treatment of seeds with organic fertilizers Nagro and Stimix, and spraying of plants with conventional plant protection products leads to reduction of attack from Phytophthora infestans and Alternaria solani in tomatoes.

Assessment of the yields of essential oil crops in Bulgaria through mathematical approaches

  1. Keranova

Department of Mathematics, Informatics and Physics, Faculty of Economics, Agricultural University, 4000 Plovdiv, Bulgaria

(Manuscript received 9 April 2018; accepted for publication 23 May 2018)


Аbstract. The present study examines the yields of the following essential-oil crops: oil-yielding rose (Rosa Damascena), peppermint (Mentha piperita), lavender (Lavendula angustifolia Mill.), coriander (Coriandrum sativum L.) and lemon balm (Melissa officinalis) in Bulgaria from 2003 to 2013 based on mathematical approaches. Correlation and regression analyses have been applied using the capabilities of the IBM Statistics SPSS 24 and the MS Excel 2010 software. The study proves the existence of positive correlations between ‘year’ and ‘yield’ of the lemon balm (r=0.609*), between oil-yielding rose and lavender (r=0.620*) and between lavender and coriander (r=0.766**) and negative association between ‘year’ and the peppermint yield (r=-0.700*). Between yields of other crops – oil-yielding rose, coriander and lavender, and between year and the yields from these crops there are no statistically proven relations. Linear regression equations are presented, showing the relation between the year and the quantity of lemon balm and peppermint production.

An assessment of farmers’ knowledge of yam entrepreneurial skills in Ekiti State, Nigeria

S.E. Komolafe, G.B. Adesiji


Department of Agricultural Extension and Rural Development, University of Ilorin, P.M.B. 1515, Ilorin, Kwara State, Nigeria


(Manuscript received 29 January 2018; accepted for publication 24 April 2018)


Abstract. This study assessed the farmers’ knowledge of yam entrepreneurial skills in Ekiti State, Nigeria. Two-stage random sampling procedure was used to select 580 respondents. Questionnaire was used to collect data. Both descriptive and inferential statistics were used to analyse the data collected. Findings show that the majority of the respondents had access to yam entrepreneurial business training/seminar (75.5%), sources of information through agricultural extension agents (86.2%), radio (83.3%) and fellow farmers (79.5%), non-member of any crop related enterprise group (66.2%). The overall farmers’ knowledge of yam entrepreneurial skills was low among the majority (62.6%). Specifically, the knowledge level of respondents on cultivation skills (=67.0) was high while management skills (=39.5), co-operation/networking (=29.3), customer/marketing skills (=27.1) and opportunity skills (=21.3) of respondents were considered low. It was, therefore, concluded that farmers’ knowledge of yam entrepreneurial skills was low. Agri-entrepreneurship training in management skills, opportunity skills, customer and marketing skills, co-operation and networking skills is recommended and encouraging the less educated yam-based entrepreneurs to participate in the agri-entrepreneurship capacity building training.