New Sources Of Variability Research Articles

The hidden world within plants: metatranscriptomics unveils the complexity of wood microbiomes.

The importance of plants as complex entities influenced by genomes of the associated microorganisms is now seen as a new source of variability for a more sustainable agriculture, also in the light of ongoing climate change. For this reason, we investigated through metatranscriptomics whether the taxa profile and behaviour of microbial communities associated with the wood of 20-year-old grapevine plants are influenced by the health status of the host. We report for the first time a metatranscriptome from a complex tissue in a real environment, highlighting that this approach is able to define the microbial community better than referenced transcriptomic approaches. In parallel, the use of total RNA enabled the identification of bacterial taxa in healthy samples that, once isolated from the original wood tissue, displayed potential biocontrol activities against a wood-degrading fungal taxon. Furthermore, we revealed an unprecedented high number of new viral entities (~120 new viral species among 180 identified) associated with a single and limited environment and with potential impact on the whole holobiont. Taken together, our results suggest a complex multitrophic interaction in which the viral community also plays a crucial role in raising new ecological questions for the exploitation of microbial-assisted sustainable agriculture.

Cognitive test scores vary with choice of personal digital device.

Mobile- and web-based psychological research are a valuable addition to the set of tools available for scientific study, reducing logistical barriers for research participation and allowing the recruitment of larger and more diverse participant groups. However, this comes at the cost of reduced control over the technology used by participants, which can introduce new sources of variability into study results. In this study, we examined differences in measured performance on timed and untimed cognitive tests between users of common digital devices in 59,587 (Study 1) and 3818 (Study 2) visitors to TestMyBrain.org , a web-based cognitive testing platform. Controlling for age, gender, educational background, and cognitive performance on an untimed vocabulary test, users of mobile devices, particularly Android smartphones, showed significantly slower performance on tests of reaction time than users of laptop and desktop computers, suggesting that differences in device latency affect measured reaction times. Users of devices that differ in user interface (e.g. screen size, mouse vs. touchscreen) also show significant differences (p < 0.001) in measured performance on tests requiring fast reactions or fine motor movements. By quantifying the contribution of device differences to measured cognitive performance in an online setting, we hope to improve the accuracy of mobile- and web-based cognitive assessments, allowing these methods to be used more effectively.

Baseline immunoreactivity before pregnancy and poly(I:C) dose combine to dictate susceptibility and resilience of offspring to maternal immune activation

Despite the potential of rodent models of maternal immune activation (MIA) to identify new biomarkers and therapeutic interventions for a range of psychiatric disorders, current approaches using these models ignore two of the most important aspects of this risk factor for human disease: (i) most pregnancies are resilient to maternal viral infection and (ii) susceptible pregnancies can lead to different combinations of phenotypes in offspring. Here, we report two new sources of variability—the baseline immunoreactivity (BIR) of isogenic females prior to pregnancy and differences in immune responses in C57BL/6 dams across vendors—that contribute to resilience and susceptibility to distinct combinations of behavioral and biological outcomes in offspring. Similar to the variable effects of human maternal infection, MIA in mice does not cause disease-related phenotypes in all pregnancies and a combination of poly(I:C) dose and BIR predicts susceptibility and resilience of pregnancies to aberrant repetitive behaviors and alterations in striatal protein levels in offspring. Even more surprising is that the intermediate levels of BIR and poly(I:C) dose are most detrimental to offspring, with higher BIR and poly(I:C) doses conferring resilience to measured phenotypes in offspring. Importantly, we identify the BIR of female mice as a biomarker before pregnancy that predicts which dams will be most at risk as well as biomarkers in the brains of newborn offspring that correlate with changes in repetitive behaviors. Together, our results highlight considerations for optimizing MIA protocols to enhance rigor and reproducibility and reveal new factors that drive susceptibility of some pregnancies and resilience of others to MIA-induced abnormalities in offspring.

Epigenetika u oplemenjivanju bilja

Current farming technology and advanced techniques of plant breeding are tending to enable high yields and cropping intensity, trying to alleviate the limitations of available arable land. However, rise in global population and climate changes could strain the ability to provide a stable food supply. Genetic diversity, which might be used for development of new, more resilient cultivars, could be a key for achieving better performance in agricultural production. New findings about how genes work and express, including the principles of epigenetics, could allow the advancements in breeding methods, and provide a new source of variability originating from epialleles. This paper provides a synopsis of the most significant epigenetic modifications, and particularities of plant species that impact epigenetic mechanisms, although it is mainly focused on application of epigenetics on plant breeding. Epigenetic aspects of breeding are described for increased yield in Brassica napus due to recursive selection for an epigenetic compound. Future application might be based on epigenetic recombinant inbred lines, similar to those in Arabidopsis thaliana, inhibition of DNA methylation in Oryza sativa, discovery of MSH1 system in Glycine max and Solanum lycopersicon. It also outlines the current issues and limitations of epigenetic breeding such as a lack of understanding of epigenetic mechanisms, interaction of epigenetic and stress responsive mechanisms, and the development of statistical models able to predict the impact and outcome of epigenetic modifications.

Selection of Canadian potato clones for agronomic and frying quality traits

ABSTRACT The demand for cultivars suitable for processing, especially as frozen French fries, is increasing in Brazil. The Canadian expertise is high regarding the development of cultivars with processing characteristics; however, the growing conditions in Canada are quite different from those observed in Brazil. Thus, the aim of this work was to evaluate the performance of Canadian potato clones for their tuber yield, frying quality, plant vigor, and plant cycle, as potential new cultivars or to be used as a new source of variability for crosses. The experiments were conducted in Pelotas-RS and Canoinhas-SC, Brazil, in spring 2017. A set of 12 advanced Canadian potato clones from the Centre de Recherche Les Buissons, QB, Canada, were compared to three control cultivars used for processing. A randomized complete block design with three replicates, with two rows of 20 plants each per plot was used. Tuber yield, frying quality, plant vigor, and plant cycle traits were evaluated. Data were submitted to analysis of variance, grouping of means, and selection gains. It is possible to select genotypes with higher tuber yield and better frying quality, but it is difficult to add also a short cycle. In an attempt to select productive genotypes, with good frying quality, a not so long cycle, and vigor at least equivalent to the control cultivars, clones 15 and 16 were the best at both sites.

The oat gene pools – review about the use of wild species in improving cultivated oat

The search for agronomic traits and the use of new sources of variability in oat farming is very important in terms of breeding. Wild species of Avena are grouped into three gene pools depending on their interfertility with cultivated hexaploid oat. The primary and tertiary gene pools are extensive and diverse, the secondary gene pool is relatively small and poorly represented in ex situ gene banks. Appropriate wild species are a valuable source of many appropriate traits such as: high protein, oil, ß-glucan and balanced amino acids composition contents in grain; short culm; cold and drought tolerance. Moreover they are a source of resistance genes for oat diseases, such as powdery mildew, crown and stem rust, smuts or BYDV. Note, however transfer of genes from wild to cultivated species is a long and laborious process. These types of methods are used in the species Avena with various end effects. The purpose of this article was to collect information on attempts of transferring different genes from wild oat species to cultivated oats.

Analyzing the Variability of the Flexural Rigidity in Pre-stressed Laminated Wood Plates

Although geometrical data describing structures are generally represented by their nominal values, practice has revealed that this is not the more appropriate for prestressed laminated wood plates, once the lamellae present significant size variability. The importance of this variability increases when it affects the height of plate cross sections, they also affect their moments of inertia which depends on the value of the height raised to the third power. Preliminary studies showed standard deviations of almost 10%. As far as stress-laminated plates are regarded, the variability of dimensions along the length of the length of the pieces introduces a new source of variability for the cross section moment of inertia. The obtained surfaces aren’t completely flat, presenting variability due the size variability along the length of the pieces. Consequently, the moment of inertia of the cross section of a stress-laminated plate is not obtained by summing up the individual moment of inertia of each piece. On the other hand, modulus of elasticity also presents a strong variability not only among the height of pieces, but also along their length. Preliminary experiments reveal a standard deviation of 23% for plates from <i>Pinus</i> <i>taeda</i>. The variability of moment of inertia of pieces and of the plate itself was determined, as well as the variability of the modulus of elasticity. The results show that rigidity just can be estimated probabilistically; that softwoods are suited for system of high redundancy; that the calculation of deformations and stress distribution along the structures are dependent on this variability and thus the referred calculations are nothing more than estimations with a certain level of confidence to be established according to the control procedures adopted; and finally that further research must be developed on probabilistic numerical factors to be incorporated to the calculation expressions of rigidity of the cross section of stress-laminated plates.

Analysis of S‐allele genetic diversity in Sicilian almond germplasm comparing different molecular methods

AbstractItalian almond germplasm is characterized by a wide diversity in several growing areas among which Sicily is one of the most important. Analysis with consensus and specific primers and DNA sequencing was performed to investigate S‐RNase genetic diversity and to elucidate the homology rate within a genetic pool of 27 Italian accessions. Interestingly, some of the self‐compatible cultivars did not show the presence of Sf allele. Amplicons from consensus and allele‐specific PCR primers revealed a high level of variability. Sequencing of all the S‐RNase amplicons derived from consensus primers allowed the identification of two new S‐RNase alleles (S51 and S52). Surprisingly, despite the AA replacement mutation, S51 did not exhibit any change of its S‐RNase function. Additionally, several mutations, with no effect on amino acid composition, were detected in the intron and/or in the ORF of four known alleles (Sg, S10, S31 and S35). Genetic variation, regarding point mutations and only detected by sequencing, was revealed among 11 of 27 tested cultivars. The new sources of variability might have an interest for product traceability.

Impact of non uniform strain configuration on transport properties for FD14+ devices

As device dimensions are scaled down, the use of non-geometrical performance boosters becomes of special relevance. In this sense, strained channels are proposed for the 14nm FDSOI node. However this option may introduce a new source of variability since strain distribution inside the channel is not uniform at such scales. In this work, a MS-EMC study of different strain configurations including non-uniformities is presented showing drain current degradation because of the increase of intervalley phonon scattering and the subsequent variations of transport effective mass and drift velocity. This effect, which has an intrinsic statistical origin, will make necessary further optimizations to keep the expected boosting capabilities of strained channels.

Epi-fingerprinting and epi-interventions for improved crop production and food quality.

Increasing crop production at a time of rapid climate change represents the greatest challenge facing contemporary agricultural research. Our understanding of the genetic control of yield derives from controlled field experiments designed to minimize environmental variance. In spite of these efforts there is substantial residual variability among plants attributable to Genotype × Environment interactions. Recent advances in the field of epigenetics have revealed a plethora of gene control mechanisms that could account for much of this unassigned variation. These systems act as a regulatory interface between the perception of the environment and associated alterations in gene expression. Direct intervention of epigenetic control systems hold the enticing promise of creating new sources of variability that could enhance crop performance. Equally, understanding the relationship between various epigenetic states and responses of the crop to specific aspects of the growing environment (epigenetic fingerprinting) could allow for a more tailored approach to plant agronomy. In this review, we explore the many ways in which epigenetic interventions and epigenetic fingerprinting can be deployed for the improvement of crop production and quality.

The variability in likelihood ratios due to different mechanisms.

Recently there has been a drive towards standardisation of forensic DNA interpretation methods resulting in the uptake of probabilistic interpretation software. Some of these software solutions utilise Markov chain Monte Carlo techniques (MCMC). They will not produce an identical answer after repeat interpretations of the same evidence profile because of the Monte Carlo aspect. This is a new source of variability within the forensic DNA analysis process. In this paper we explore the size of the MCMC variability within the interpretation software STRmix™ compared to other sources of variability in forensic DNA profiling including PCR, capillary electrophoresis load and injection, and the makeup of allele frequency databases. The MCMC variability within STRmix™ was shown to be the smallest source of variability in this process.

Broadening the genetic base of Abyssinian mustard (Brassica carinata A. Braun) through introgression of genes from related allotetraploid species

Brassica carinata (BBCC, 2n=34) has still to emerge as a major oilseed crop owing to poor agronomic attributes like long stature, long maturity duration and low seed yield. The restricted amount of genetic variability available in natural B. carinata necessitates utilization of new sources of variability for broadening its genetic base. Interspecific hybridization followed by selection in selfed and back cross progenies was employed to generate useful variability into B. carinata cv ˈPC5ˈ from elite lines of Brassica napus (AACC, 2n=38) and Brassica juncea (AABB, 2n=36). The morphological evaluation of 24 stable introgressed progenies revealed wide range of variability for key economic traits. The progenies with mean maturity duration of 161 ± 2.1 days, short stature of 139.5 ± 6.5 cm and seed yield per plant of 18.6 ± 2.0 g in comparison to the corresponding figures of 168 ± 4.6 days, 230.6 ± 12.7 cm and 12.0 ± 2.4 g in ˈPC5ˈ (recurrent parent) were recovered. Diversity analysis at morphological level revealed that 22 out of 24 stable introgressed progenies were grouped with B. carinata ˈPC5ˈ at average taxonomic distance of 1.19. The diversity at molecular level using 25 polymorphic and reproducible RAPD primers revealed that 19 out of 21 introgressed progenies grouped with B. carinata ˈPC5ˈ at a similarity coefficient of 0.68. The clusters in general represent a wide range of genetic diversity in the back cross lines of B. carinata as a result of introgression of genes from elite lines of B. napus and B. juncea parents.

The effect of Congo River freshwater discharge on Eastern Equatorial Atlantic climate variability

The surface ocean explains a considerable part of the inter-annual Tropical Atlantic variability. The present work makes use of observational datasets to investigate the effect of freshwater flow on sea surface salinity (SSS) and temperature (SST) in the Gulf of Guinea. In particular, the Congo River discharges a huge amount of freshwater into the ocean, affecting SSS in the Eastern Equatorial Atlantic (EEA) and stratifying the surface layers. The hypothesis is that an excess of river runoff emphasize stratification, influencing the ocean temperature. In fact, our findings show that SSTs in the Gulf of Guinea are warmer in summers following an anomalously high Congo spring discharge. Vice versa, when the river discharges low freshwater, a cold anomaly appears in the Gulf. The response of SST is not linear: temperature anomalies are considerable and long-lasting in the event of large freshwater flow, while in dry years they are less remarkable, although still significant. An excess of freshwater seems able to form a barrier layer, which inhibits vertical mixing and the entrainment of the cold thermocline water into the surface. Other processes may contribute to SST variability, among which the net input of atmospheric freshwater falling over EEA. Likewise the case of continental runoff from Congo River, warm anomalies occur after anomalously rainy seasons and low temperatures follow dry seasons, confirming the effect of freshwater on SST. However, the two sources of freshwater anomaly are not in phase, so that it is possible to split between atypical SST following continental freshwater anomalies and rainfall anomalies. Also, variations in air-sea fluxes can produce heating and cooling of the Gulf of Guinea. Nevertheless, atypical SSTs cannot be ascribed to fluxes, since the temperature variation induced by them is not sufficient to explain the SST anomalies appearing in the Gulf after anomalous peak discharges. The interaction processes between river runoff, sea surface salinity and temperature play an effective role in the interannual variability in the EEA region. Our results add a new source of variability in the area, which was often neglected by previous studies.

The effect of tetraploidization of wild Arachis on leaf morphology and other drought-related traits

Cultivated peanut is an allotetraploid (genome type AABB) with a very narrow genetic base, therefore wild species are an attractive source of new variability and traits. Because most wild species are diploid, the first step of introgression usually involves hybridization of wild species and polyploidization to produce a synthetic allotetraploid (AABB) that is sexually compatible with peanut. This study investigates drought-related traits such as leaf morphology, transpiration profile, chlorophyll meter readings (SCMR), specific leaf area (SLA) and transpiration rate per leaf area for two wild diploids (Arachis duranensis and Arachis ipaënsis) that could be of interest for improvement of the peanut crop. Furthermore, the inheritance of the traits from the diploid to the tetraploid state was investigated. Results showed that whilst some diploid traits such as SCMR, are maintained through hybridization and polyploidization, most characters, such as the leaf area, stomata size, trichome density and transpiration profile, are substantially modified. The study concludes that direct evaluations of drought-related traits in wild diploids may be useful for evaluation of wild species to be used in introgression. However, evaluations on wild-derived synthetic tetraploids are likely to be more informative.

Different manufacturers of syringes: A new source of variability in blood gas, acid–base balance and related laboratory test?

Evaluate whether four different brands/types of heparin coated syringes can represent a source of variability in blood gas analysis (BGA). Blood was collected from one hundred volunteers into different syringes: Syringe I (lithium heparin and calcium balanced); Syringe II: in-house prepared (sodium heparin); Syringe III: (spray-dried calcium-balanced lithium heparin); Syringe IV (lyophilized electrolyte-balanced lithium heparin). Significant differences were as follows: a) Syringe I vs II: pO(2), sO(2), pCO(2)(t), cHCO(3)(-), ctCO(2), base excess (BE), total hemoglobin (tHb), sodium (Na(+)), potassium (K(+)), calcium (Ca(2+)), glucose (Glu), lactate (Lac), O(2) Hb and p 50; b) Syringe I vs III: pH, pO(2), cHCO(3)(-), ctCO(2), BE, Na(+), Glu, Lac and p 50; c) Syringe I vs IV: pH, pO(2), sO(2), pCO(2)(t), BE, Na(+), K(+), Ca(2+), Glu, Lac and O(2) Hb; d) Syringe II vs III: pH, pO(2), sO(2), pCO(2)(t), cHCO(3)(-), ctCO(2), ctO(2), tHb, Na(+), K(+), Ca(2+), Lac and p 50; e) Syringe II vs IV: pH, pO(2), sO(2), pCO(2)(t), cHCO(3)(-), ctCO(2), BE, tHb, Na(+), K(+), Ca(2+), Lac, O(2) Hb and p 50; f) Syringe III vs IV: pH, pO(2), sO(2), cHCO(3)(-), ctCO(2), ctO(2), BE, Na(+), K(+), Ca(2+), O(2) Hb and p 50. The different manufacturers of syringes can represent new source of variability on BGA.

Grain-Orientation Induced Work Function Variation in Nanoscale Metal-Gate Transistors—Part I: Modeling, Analysis, and Experimental Validation

This paper highlights and experimentally verifies a new source of random threshold-voltage (V_th) fluctuation in emerging metal-gate transistors and proposes a statistical framework to investigate its device and circuit-level implications. The new source of variability, christened work-function (WF) variation (WFV), is caused by the dependence of metal WF on the orientation of its grains. The experimentally measured data reported in this paper confirm the existence of such variations in both planar and nonplanar high-k metal-gate transistors. As a result of WFV, the WFs of metal gates are statistical distributions instead of deterministic values. In this paper, the key parameters of such WF distributions are analytically modeled by identifying the physical dimensions of the devices and properties of materials used in the fabrication. It is shown that WFV can be modeled by a multinomial distribution where the key parameters of its probability distribution function can be calculated in terms of the aforementioned parameters. The analysis reveals that WFV will contribute a key source of V_th variability in emerging generations of metal-gate devices. Using the proposed framework, one can investigate the implications of WFV for process, device, and circuit design, which are discussed in Part II.

In vitro propagation using adventitious buds technique as a source of new variability in chrysanthemum

Eleven cultivars of Chrysanthemum × grandiflorum (Ramat.) Kitam.: ‘Richmond’ and its 10 radiomutants, representing the Lady group, were propagated in vitro with shoot tips and leaves as explants. The aim of this study was to investigate if the explant type used for micropropagation affects the genotype and phenotype of chrysanthemums. Plants grown from shoot tips and adventitious buds formed on leaves were rooted in vitro, acclimatized and cultivated in glasshouse up to full-flowering. The colour and shape of inflorescences of plants obtained from two different explant types were compared within the cultivars. All plants derived from shoot-tip explants showed the inflorescence colour and shape typical for the cultivars. Inflorescence colour of plants derived from adventitious buds were true-to-type in four cultivars: ‘Richmond’, ‘Lady Amber’, ‘Lady White’ and ‘Lady Yellow’. All plants of ‘Lady Apricot’ (originally: golden beet) and ‘Lady Salmon’ (salmon) propagated from adventitious buds technique showed altered inflorescence colour (respectively: purple gold; pink and white). ‘Lady Bronze’ (originally: reddish brown), ‘Lady Orange’ (orange brown) and ‘Lady Rosy’ (purple gold) propagated with adventitious buds had both typical and changed inflorescence colours (respectively: yellow; yellow and red; reddish pink). ‘Lady Vitroflora’ showed altered number of ligulate florets grown into tubes in inflorescence when propagated with shoot tips and leaves as explants. Those changes might be an effect of either chimeral structure or somaclonal variation of the plants investigated. The variation appears only if non-meristematical explants were used. The adventitious buds technique might be useful in chrysanthemum breeding as a source of a new variability.

Variation in fiberoptic bead-based oligonucleotide microarrays: dispersion characteristics among hybridization and biological replicate samples

BackgroundGene expression microarray technology continues to evolve and its use has expanded into all areas of biology. However, the high dimensionality of the data makes analysis a difficult challenge. Evaluating measurements and estimating the significance of the observed differences among samples remain important issues that must be addressed for each technology platform. In this work we use a consecutive sampling method to characterize the dispersion patterns of data generated from Illumina fiberoptic bead-based oligonucleotide arrays.ResultsTo describe general properties of the dispersion we used a linear function SD = a + bYmean, approximating the standard deviation across arrays (Ymean is the mean expression of a given consecutive sample). First we examined three levels of variability: 1) same cell culture, same reverse transcription, duplicate hybridizations; 2) same cell culture, reverse transcription replicates; 3) parallel cultures. Each higher level is expected to introduce a new source of variability. We observed minor differences in the constant term: the mean values are 3.5, 3.1 and 3.5, respectively. However, the mean coefficient b increased from 0.045 to 0.147 and 0.133. We compared the coefficients derived from the consecutive sampling to those obtained from the standard deviation of individual gene expressions and found them in good agreement. In the second experiment samples we detected 11 genes with systematically different expressions between the experiment samples treated with glucose oxidase and controls and corroborated the selection using the Mann-Whitney and other tests. We also compared the consecutive sampling and coincidence method to t-test: the average percentage of consistency was above 80 for the former and below 50 for the latter.ConclusionOur results indicate that the consecutive sampling method and standard deviation function provide a convenient description of the overall dispersion of Illumina arrays. We observed that the constant term of the standard deviation function is at average approximately the same for duplicate hybridization as for the assays with additional sources of variability. Furthermore, among the genes affected by glucose oxidase treatment we identified 6 genes in oxidative stress pathways and 5 genes involved in DNA repair. Finally, we noted that the consecutive sampling and coincidence test provide, under given conditions, more consistent results than the t-test.ReviewersThis article was reviewed by Alexander Karpikov (nominated by MarkGerstein), Jordan King and Eugene V. Koonin.

Portlet syndication

A Portlet is a multistep, user-facing application delivered through a Web application (e.g., a portal). OASIS approved standard, WSRP, is an attempt to standardize the interface between the provider and the consumer of the Portlet. This initiative promotes Portlet interoperability, componentware practices, and the existence of a Portlet market. This work argues that the diversity of the settings where a Portlet might be syndicated recommends that Portlets be instrumented for variability, and this, in turn, demands a product-line approach. This work introduces a new source of variability, the “interaction lifecycle”, a description of the visible flow of a Portlet, and shows how this feature can be adapted to cater to the idiosyncrasies of the hosting application. Distinct variants are identified that permit the consumer to customize the presentation, content, and links of the Portlet markup in a controlled way. The use of product-line techniques allow the consumer to cope with this variability in a cost-effective manner. The article ends by illustrating how the extensible capabilities of WSRP are used to accomodate this process.

Characteristics of Maize Inbred Lines Originating from Local Populations

Maize is the leading field crop in Yugoslavia in terms of economic importance and area sown. Over the past 400 years, which is how long maize has been grown in the country, a rich breeding material with a unique combination of agronomic traits has been developed under the influence of agroecological factors and through constant selection of desirable fenotypes. When the spread of hybrid maize began in the mid-20th century, local breeding materials were collected and assembled in gene banks in order to prevent their deterioration and enable their utilization in breeding to develop hybrid varieties. The present study includes only those lines from the first cycle of selection originating from the local populations Vukovarski Zuti Zuban, Sidski Zuti Zuban, Novosadski Zlatni Zuban, Bankut Bajsa, Socice, and Novosadski Zuti Zuban that were used for the development of commercial hybrids, which is less than 1% of the total number of inbred lines developed at the Institute of Field and Vegetable Crops in Novi Sad. The contribution of domestic inbred lines to modern maize breeding consists in the following: 1) Domestic inbred lines possess great variability for most of the agronomically important traits. In nearly every group of lines (lines of the same origin comprise one group), lines with desirable traits have been found, lines that now represent new sources of variability in breeding programs on. grain yield, resistance to lodging, early maturity, ear bareness, grain quality, and other traits. 2) The domestic inbreds differ in their heterotic potential for grain yield when crossed with the inbred testers B73 (BSSS germplasm type) and Mol7 (Lancaster germplasm type). Lines originating from the populations Vukovarski Zuti Zuban, Sidski Zuti Zuban, Novosadski Zlatni Zuban, and Novosadski Zuti Zuban combine better with the inbred tester Mol7 than with B73, so they belong to the BSSS heterotic group. Lines originating from the populations Bankut Bajsa and Socice are neutral, i.e. they respond equally to both types of germplasm (BSSS and Lancaster), so they can be said to belong to a new heterotic group.