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Open access

Manfred Jakop, Silva Grobelnik Mlakar, Martina Bavec, Martina Robačer, Tjaša Vukmanič, Urška Lisec and Franci Bavec

Abstract

In 2013 and 2014, a long-term trial (which was established in 2007) was conducted at the University Agricultural Centre in Pivola near Hoče. It included different production systems (conventional, integrated, organic, biodynamic), carried out in a field trial with oil pumpkins. The aim of the research was to analyse the effects of different production systems, varieties (hybrid and population variety) and years of production, on formation of oil pumpkin yields. The agricultural practice has been carried out in accordance with the applicable legislations and standards for the individual production system. When sowing, before fertilizing with nitrogen in early June and after the harvest, the amount of soil mineral nitrogen was monitored. We evaluated the number and weight of harvestable, unripe and decayed fruits, and yield of oil seed pumpkins and calculated the agronomic efficiency of the applied nutrients. The results showed that the year of production, the production system and the variety have a significant effect on some fruit characteristics and the yield of oil pumpkin seeds. The content of soil mineral nitrogen in May and September was significantly influenced by the production system and the year. In June, only the production system had a significant effect. The hybrid significantly increased the yields of oil pumpkin seeds in all production systems, even in the year that was less suitable for production. The agronomic efficiency of the applied nutrients in the biodynamic and organic production system is higher or equal than in the conventional production system, similarly, agronomic efficiency is higher in the hybrid compared to the oldest population variety efficiently. A comparable oil pumpkin yield can be expected in biodynamic and organic production, when proper nutrition and well carried out cultivation practices are combined with a new variety, when compared to less sustainable production systems, which often cause damage to the environment.

Open access

Peter-Damian Chukwunomso Jiwuba, Lydia Chidimma Jiwuba and Moses Udoha Onyekwere

Abstract

The growth performance, haematological and serum biochemical characteristics of thirty-six West African Dwarf (WAD) sheep of about 10 - 12 months of age and averaged 8.53kg in weight were sourced from the College flock. Four dietary treatments designated as T1, T2, T3 and T4 were formulated to contain 0%, 10%, 20% and 30% oil palm leaf meal (OPLM) respectively were randomly assigned to the animals. The experimental animals were divided into four groups of nine animals each, with each group replicated thrice with three animals per replicate. Each group was allotted to one of the diets in a completely randomized design. The animals were weighed at the beginning of the trial and weekly subsequently and data for growth performance were generated. Blood samples were obtained from one animal in each replicate, and data generated were analyzed statistically. Average daily feed intake, total dry matter intake and average daily weight gain were significantly (P<0.05) influenced by the dietary treatment, with animals on T4 group having higher and better values. Feed conversion ratio (FCR) also differed significantly (P<0.05) with sheep on T3 and T4 (11.82 and 11.49 respectively) having the best FCR. The haematology showed that the packed cell volume (PCV), red blood cell (RBC), and mean cell haemoglobin concentration (MCV) were significantly (P < 0.05) improved at 10%, 20% and 30% inclusion levels of OPLM, respectively. Sheep in treatment groups had improved (P < 0.05) white blood cell (WBC) count than those on the control group. Serum biochemistry results showed that total protein, albumin and globulin were significantly influenced (P < 0.05) and tended to increase with increasing levels of test ingredient. Sheep in treatment groups had higher (P < 0.05) urea values than those on control. Creatinine values at 20% and 30% inclusion differed significantly (P < 0.05) with the control value. Cholesterol was significantly influenced (P < 0.05) and followed an irregular trend across the treatment groups. The results showed that inclusion of OPLM had a beneficial effect on the general performance of the WAD sheep. Therefore, 30% OPLM supplementation was recommended for optimum performance in WAD sheep.

Open access

Barbara Videc and Jurij Rakun

Abstract

This paper presents a method of estimating the size of plants by using two parallel views of the scene, taken by a common digital camera. The approach relays on the principle of similar triangles with the following constraints: the resolution of the camera is known; the object is always in parallel to the camera sensor and the intermediate distance between the two concessive images is available. The approach was first calibrated and tested using one artificial object in a controlled environment. After that real examples were taken from agriculture, where we measured the distance and the size of a vine plant, apple and pear tree. By comparing the calculated values to measured values, we concluded that the average absolute error in distance was 0.11 m or around 3.7 %, and the absolute error in high was 0.09 m or 4.6 %.

Open access

Valiollah Rameeh

Abstract

Information on estimates of combining ability of the promising lines of breeding material is important for evolving higher yielding varieties of oilseed rape (Brassica napus L.). An experiment was conducted to quantitatively examine the genetic parameters of phenological traits, plant height, pods on main raceme, pods per plant and seed yield for eight oilseed rape genotypes using a half-diallel crosses. The result of the diallel analysis revealed significant mean squares of general and specific combining abilities (GCA and SCA) for all studied traits, indicating the importance of additive and non-additive genetic effects for these traits. On the other hand estimation of high narrow-sense heritability estimates for days to flowering, duration of flowering and pods on main raceme, indicated the prime importance of additive genetic effects for these traits. L420 and L401 with significant negative GCA effects for days to flowering and days to maturity were suitable for yielding early maturity combinations. L41, Zafar and L22 with significant positive GCA effects for seed yield were superior parents for increasing seed yield. The crosses with significant positive SCA effects for seed yield had at least one parent with significant positive GCA effects for this trait. The crosses including L41×L22, L41×LF2, Zafar×L22 and Zafar×L420 with seed yield of 3421.7, 3400, 3348.1 and 3311.3 kg ha-1 could be promising for determination of superior recombinants for high seed yield coupled with other growth characters in advanced generations of segregation.

Open access

Peter-Damian Chukwunomso Jiwuba, Ifeanyi Princewill Ogbuewu, Elisha Dauda and Caritas Chibuike Azubuike

Abstract

The responses of 96 day old broilers fed Chromolaena odorata leaf meal (COLM) on blood profile and gut microbial load were studied for 49 days. The birds were randomly assigned to four treatment groups and replicated three times in a completely randomized design. The birds were fed four experimental diets formulated at 0%, 2%, 4% and 6% for the starter phase and 0%, 4%, 8% and 12% of COLM at the finisher phase for T1, T2, T3 and T4 respectively. All the haematological parameters were similar (P>0.05) across the treatment groups except MCH and WBC which were significantly (P< 0.05) higher and better in the treatment groups than the control group. The results on serum chemistry showed significant (P<0.05) difference for total protein, albumin, creatinine and cholesterol across the treatment groups. Cholesterol was significantly (P<0.05) reduced with increasing levels of COLM. Results showed that coliforms and E.coli were consistently higher (P<0.05) among the T1 birds than those fed T2, T3 and T4. It was concluded that, COLM enhanced adequate haematocrit and immune status, hypoglycaemic ability, suppresses the growth of gut pathogenic microorganisms and enhanced the growth of beneficial microorganism in broilers.

Open access

Tadeja Jere Jakulin

Abstract

Agritourism as a type of niche tourism is a complex and softly defined phaenomenon. The demands for fast and integrated decision regarding agritourism and its interconnections with environment, economy (investments, traffic) and social factors (tourists) is urgent. Many different methodologies and methods master softly structured questions and dilemmas with global and local properties. Here we present methods of systems thinking and system dynamics, which were first brought into force in the educational and training area in the form of different computer simulations and later as tools for decision-making and organisational re-engineering. We develop system dynamics models in order to present accuracy of methodology. These models are essentially simple and can serve only as describers of the activity of basic mutual influences among variables. We will pay the attention to the methodology for parameter model values determination and the so-called mental model. This one is the basis of causal connections among model variables. At the end, we restore a connection between qualitative and quantitative models in frame of system dynamics.

Open access

Andrej Šušek

Abstract

The Christmas rose is becoming a very important ornamental plant on the market. It is relatively new to intensive production technologies. The number of genetically-improved varieties on the market is limited, and many of the old cultivars are no longer available because of slow and economically unfeasible vegetative propagation. In the future, its genetic improvement will probably become inevitable. New cultivars will have to satisfy the specific requirements of the market and producers as well as strict environmental policy. In order to obtain new cultivars it will be necessary to evaluate the existing germplasm and apply an adequate genetic breeding approach. There are seven main possibilities of creating new varieties: the use of natural variation associated with seed germination, population approach based on recurrent selection, individual selection based on specific genetic combinations, the creation of inbred lines and the formation of hybrids, interspecific hybridisation, mutagenesis and genetic engineering. Molecular markers can be very helpful during the breeding process. They can be used in order to study genetic relationships amongst populations, ecotypes, varieties, and hybrids.

Open access

Maša Primec

Abstract

A rapid microbial detection in different biological and environmental material is a key of preventing several foodborne diseases. By implementing nanotechnology into food safety sector, a great step towards successful, reliable and sensible detection methods of foodborne pathogens has been achieved. Therefore, the aim of this review was to illustrate some of the principal functions of nanotechnology-based techniques, used for microbial detection in the last few years. Regarding consumer’s health, the review also discusses the question of safety, concerning human exposure to nanomaterials (NMs). Due to their different composition-unique properties, such as greater penetrability, reactivity and high surface to volume ratio, NMs have been coupled to several biomolecules and integrated in special system devices, resulting in improvement of sensitivity in transmitting biological signal informations in a shorter time. Among all the NMs, gold, magnetic and fluorescent nanoparticles (NPs) have been widely used, also in microbial diagnosis. Despite the success of linking nanotechnology to detection of foodborne pathogens, the exposure to various NMs could also be a matter of potential risk to human health, although conclusions still need to be definitely proven.

Open access

Metka Šiško

Abstract

The effect of sterilisation treatments on the initiation of the culture of three Hydrangea macrophylla genotypes in vitro was studied. The results indicated difference among different disinfection treatment; the consequence of treatments with dichloroisocyanuric acid, in combination with silver nitrate, was a significantly higher survival rate comparing to treatments based on NaOCl. Success of sterilisation was significantly influenced by studied genotypes. Two potted hydrangea genotypes (G2 and G3) showed higher survival rate (45.00 %, 55.00 %, respectively) comparing to the genotype 1 (originated from a local garden), which exhibited the highest percentage of contamination rate (58.75 %). Culturing the explants on a McCown woody plant medium supplemented with BAP at 2 mg/L and NAA at 0.005 mg/L produced the highest number of shoots with multiplication rate of 1.31 in 5 weeks. The highest rooting percentage (100.00 %) was obtained with the genotype 2 on a McCown woody plant medium supplemented with 0.5 mg/L IBA.

Open access

Livija Tušar, Irena Leonida Kropf and Avrelija Cencič

Abstract

Salt is an important ingredient in the production of meat product. Any reduction of salt requires a special treatment. This study was conducted to evaluate the effect of salt reduction on the growth of microorganisms in Kranjska sausages during their shell-life and to carry out a sensory assessment. The 18 lots of sausages were prepared under salt-reduced (1.6%) and control (2.3%) salt concentrations, directly on the production line. A total of 85 sausages were analysed and the data were used for the comparisons of groups (ANOVA) and to detect the significant variables (polynomial models) influenced on the total number of microorganisms (TNMs). The significant differences were determined between the lots (representing the microbiological status of the stuffing), between the salt-reduced samples and control samples, and between the different humidity levels. The correlations and significant relationships were determined between the TNMs and the lots, the salt concentrations, and the relative humidity. The polynomial models were to general to be used for the prediction. For sensory analysis implemented on 40th day 18 sausages were assessed. The reduction of salt resulted in lower scores in the sensory evaluation. The less-salted sausages contained more microorganisms.