Stability Of Variety Research Articles

Effect of Spinning Systems on Properties of Dyed Egyptian Cotton Yarns after Mercerization Treatment

The effects that spinning technology and spinning parameters have on the color strength (K/S), strength, and breaking elongation of post dyed and mercerized yarns are investigated in this study. The emphasis of the study is on the selection of long stable Egyptian cotton varieties, namely Giza 80, Giza 86, and extra long stable Giza 92. The cotton samples are spun by using compact, ring, and open end spinning technologies. For the purpose of this study, different yarn counts and twist multipliers are used. The mechanical properties, such as the tensile strength and breaking elongation of the produced yarn are investigated and compared before and after the mercerization treatment (slack and tension), followed by a reactive dyeing process. All of the samples are prepared for dyeing after mercerization. The dyeing performance in terms of the K/S is studied. When the results are examined, it is found that the samples that have undergone (bleaching + slack mercerization + reactive dyeing) generally have higher K/S values than samples that have undergone (bleaching + tension mercerization + reactive dyeing) and (bleaching + non-mercerization + reactive dyeing) respectively. Open-end spun yarns have a higher K/S compared to the compact and ring spun yarns with the lowest count yarn and twist level. The strength percentages are higher for compact, then ring and finally open-end spun yarns respectively with tension mercerization. There is no noticeable difference in the elongation% for all of the treatment processes. The authors have used quality engineering reproducibility and repeatability (R&R) tools to guarantee the repeatability and reproducibility of the results in this research paper.

On the boundary behavior of Kähler–Einstein metrics on log canonical pairs

In this paper, we study the boundary behavior of the negatively curved Kahler–Einstein metric attached to a log canonical pair (X, D) such that $$K_X+D$$ is ample. In the case where X is smooth and D has simple normal crossings support (but possibly negative coefficients), we provide a very precise estimate on the potential of the KE metric near the boundary D. In the more general singular case (D being assumed effective though), we show that the KE metric has mixed cone and cusp singularities near D on the snc locus of the pair. As a corollary, we derive the behavior in codimension one of the KE metric of a stable variety.

Assessment of adaptability of recently released salt tolerant rice varieties in coastal regions of South Bangladesh

Productivity of rice is adversely affected by salinity and water logging stresses in coastal zones, and affected areas are progressively expanding as consequences of climate change and overexploitation of natural resources to meet the needs of increasing populations. Several varieties were developed and commercialized in this region in recent years, including some salt and stagnant flood (SF, medium deep, 25–50cm water depth) tolerant varieties. However, suitability of these varieties based on adaptation to local conditions across the region and farmers’ preferences have not been sufficiently evaluated. Genotype by environment analysis leads to identification of varieties with stable performance, or suitability to specific regions. Two frequently used statistical analyses are additive main effects and multiplicative interaction (AMMI); and the genotype main effects and genotype×environment interaction effects (GGE). These models were used in this study to identify stable rice varieties for the wet and dry seasons in South Bangladesh. Experiments were conducted at six sites over four years (2010–2013) in coastal Bangladesh, using eight and five varieties for wet and dry season, respectively. The trials were laid in a randomized complete block design (RCBD) with three replications. Genotypic contribution was much higher than the environmental effect on grain yield in the wet season, while the environmental contribution was much higher than genotypic effect during the dry season. SF stress affected yield of wet season rice; but in the dry season, salinity stress had major effect on grain yield. The variety BRRI dhan54 was identified as the most suitable genotype with wider adaptability in the region during the wet season, followed by BRRI dhan40 and BRRI dhan53, while BRRI dhan47 was the most stable variety followed by BRRI dhan61 and BINA dhan8 for the dry season across all sites. However, when these varieties were evaluated based on farmers’ preferences in participatory varietal selection, BRRI dhan53; a short duration variety with medium slender grains was the most preferred, followed by BRRI dhan54 and BRRI dhan40 for wet season, and in the dry season BRRI dhan47 was the most popular variety followed by BRRI dhan61, which agreed with ranking based on yield. Modern varieties were far superior over traditional varieties based on grain yield and farmers’ preferences, and should be targeted for large-scale seed production and dissemination.

Selection for High Yield and Stability among Early Maturing Greengram Genotypes

Greengram, Vigna radiata (L.) Wilczek is an important source of proteins and micronutrients to small holder farmers in eastern and northern regions of Uganda. Most of the landraces currently grown by small scale farmers are characterized by low yields and late maturity. In order to identify high yielding and stable varieties, an experiment was conducted to evaluate the yield performance of introduced early maturing genotypes from the World Vegetable Centre (AVDRC) in seven locations of Uganda. Yield performance data for the genotypes was subjected to analysis of variance (ANOVA) to test the significance of genotype × environmental interactions as well as stability analysis using the yield – stability statistic (YSi) as an aid for simultaneous selection for high yield and stability. Analyses of variance showed that genotype × environmental interactions (G×E) were significant and therefore could not be ignored. Following the detection of significant genotype × environmental interactions, yield – stability statistics (YSi) were generated and used for simultaneous selection for high yield and stability among the introduced genotypes. Yield-stability statistics (YSi), indicated that three introduced genotypes (Filsan, Sunshine, and Blackgram) in addition to the local check were stable and high yielding. These genotypes need to be assessed for farmer preferences/tastes and other quality traits in on-farm participatory trials before they can be recommended for release.

Fibered stable varieties

We show that if a stable variety (in the sense of Kollár and Shepherd-Barron) admits a fibration with stable fibers and base, then this fibration structure deforms (uniquely) for all small deformations. During our proof we obtain a Bogomolov-Sommese type vanishing for vector bundles and reflexive differential n − 1 n-1 -forms as well.

Abstract P243: Greater Healthful Dietary Variety and Changes in Adiposity Indicators During a Weight-Loss Intervention: The POUNDS Lost Trial

Background: Adhering to a healthy lower energy diet is essential for sustained weight loss. Greater variety within energy-poor, nutrient-dense foods may improve adherence by making the diet less monotonous, and therefore more enjoyable. Greater healthful dietary variety has been inversely associated with adiposity in cross-sectional studies, but it is unclear if it predicts longitudinal changes in body weight. Objective: To examine the longitudinal associations between initial changes in healthful dietary variety (0-6 months) and long-term changes in adiposity over 24-months in a weight-loss trial. Methods: Participants in the POUNDS Lost trial were advised to follow energy-restricted diets. Data for participants with complete dietary assessments at baseline and 6-months were analyzed (n=367). Healthful dietary variety was quantified using the validated US Healthy Food Diversity (US HFD) index, which measures the number of foods consumed and consistency of dietary selections and amounts with recommendations from the 2010 Dietary Guidelines for Americans. Changes in the US HFD index between baseline and 6-months were divided into tertiles (T); adults in T1 had reductions in the US HFD index, T2 maintained stable index values, and T3 had increased index values. Body weight and waist circumference (WC) were measured at 6, 12, 18, and 24-months and percent body fat and trunk fat were measured at 6 and 24-months using DEXA. Repeated measures ANOVA was used to test whether US HFD index change tertiles were significantly associated with adiposity over 24-months. Models were adjusted for age, sex, race, smoking, education, income, diet arm, changes in physical activity and energy intake, baseline adiposity indicator, and the interaction between the US HFD index change tertile and time. Results: Reductions in energy intake were equivalent across US HFD index change tertiles in multivariable models (-425 vs.-265 kcal in T1 vs.T3, p=0.08). An improved variety (T3) as compared to stable variety (T2) was associated with greater weight loss at 24-months (-4.75 vs. -2.63kg, p=0.03; linear p-trend=0.04) and greater decrease in total body fat in T3 vs. T2 (-1.10% vs. -0.006%, p=0.03; p-trend=0.04) and trunk fat (-1.29% vs. 0.08%, p=0.03; p-trend=0.04). An improved variety (T3) as compared to stable variety (T2) or reduced variety (T1) was associated with greater reduction in WC (-6.48cm (T3) vs. -3.98cm (T2), p=0.01; and -4.14cm (T1), p=0.04; linear p-trend=0.01). Reducing variety (T1) did not reduce or increase other adiposity indicators compared to stable or increased variety. Conclusions: Increasing healthful dietary variety while restricting energy intake may improve sustained reductions in adiposity among adults trying to lose weight.

Functional materials based on multinary salt systems

We describe the steps of studies into multinary salt systems necessary for functional materials design. The potential of phase trees is demonstrated for predicting crystallizing phases and searching for phase-separation simplexes and simplexes with maximal or minimal melting temperatures. An algorithm is proposed for predicting properties of eutectic compositions in four-, five-, and six-component systems involving the description of the lower and upper bounds of the properties proceeding from relevant data on one-, two-, and three-component systems. In addition, two new physicochemical concepts are proposed for use in materials design in salt systems, namely, the equalization concept and the stable variety concept.

MODEL OF HIGH SEED PRODUCTIVENESS IN FORAGE PEA VARIETIES

A linear equation of regression was used for establishment of the influence of quantitative characteristics on the grain productivity in forage pea and for development of a model for breeding work. The model for pea plant with high productivity was characterized by average height of 60–70 cm, 8–10 formed pods, 30–40 seeds per plant and 160–260 g in regard to 1000-seed weight.The obtained results showed that the greatest effect on grain productivity had the seed number per plant, first pod height and 1000-seed weight. Kristal variety had high ecological plasticity and could be considered as close to an ideal type, suitable for growing under wide range of environments. Pleven 4 and Rezonator were determined as high-productive varieties and with low stability, Kerpo and Pikardi - as low-productive but stable varieties. Druzba was identified as unstable and low-productive variety.

The effect of ensiling on variety rank of maize silage

O variety trials with maize silage determine quality parameters in fresh (i.e., unconserved) samples. However, farmers use silage as daily component of cattle diet. Quality changes (crude protein and starch content, NDF, organic matter (OMD) and cell wall digestibility (DNDF)) during ensiling have been studied extensively. It is as yet unclear if the variety rank based on the quality of fresh maize samples is similar with the variety rank based on the quality of ensiled maize samples. In our research, eight maize silage varieties were monitored at six harvest dates (from 250 to 400 g/kg dry matter content) in Merelbeke (Belgium). At each harvest date, fresh samples were taken and half of the sampled material was ensiled in laboratory silos for three months. We analyzed the data with Analyses of Variance and concluded that the variety rank was stable at any harvest date if the interaction between variety and ensiling was not significant. Quality changes during ensiling resulted in a change of variety rank depending on the dry matter content at harvest. Reporting variety ranks based on fresh material continues to be a good practice for crude protein and starch content. However, changes in variety ranks based on OMD, NDF and DNDF occurred at a higher frequency. For each quality parameter, a stable variety rank was only guaranteed at the first harvest date corresponding with a dry matter content of 250g/kg.

Stability for grain yield and its contributing traits in bread wheat (Triticum aestivum)

In a study set of forty seven genotypes of common bread wheat (Triticum aestivum L. emend Fiori & Paol) were evaluated over four years during 2007-08 to 2010-11 to assess the stability of these genotypes for yield and its contributing traits over years and environments. Analysis of variance of stability with respect to 12 traits revealed highly significant variance due to environment for all traits which indicated differential effect of different seasons. The variance for genotypic effect was highly significant for all traits indicating thereby differential response of all the genotypes. Genotype×environment (linear) interaction was also significant for flag leaf length, flag leaf width, peduncle length, grains per spike and 1000-grain weight indicating substantial amount of predictable G×E interaction. Environmental indices indicated that performance of genotypes over four environments varied apparently and environment E2 showed highest favourable impact on grain yield. Varieties K 9107, UP 2382 and PBW 443 were found to be stable across the environments for grain yield and NW 1076 was the highest yielding stable variety in which superior yield was resulted from high mean values of six contributing traits, while variety LOK 1 was the only variety showed stable performance for all 12 traits. The stability of different yield contributing traits varied in compensating manner in different genotypes imparted grain yield stability. The varieties HD 2824, UP 2382, NW 1076, DBW 16, DBW 39, GW 173, HUW 234, NIAW 917, LOK 1, HD 2851 and PBW 154 have shown higher mean values, desirable regression coefficient and non-significant deviation from the regression coefficient for yield and its contributing traits. Based on stability parameters these varieties can be considered as stable performers and may be utilized for hybridization programmes to improve wheat yields.

Kähler–Einstein Metrics on Stable Varieties and log Canonical Pairs

Let X be a canonically polarized variety, i.e. a complex projective variety such that its canonical class K (X) defines an ample -line bundle, and satisfying the conditions G (1) and S (2). Our main result says that X admits a Kahler-Einstein metric iff X has semi-log canonical singularities i.e. iff X is a stable variety in the sense of Kollar-Shepherd-Barron and Alexeev (whose moduli spaces are known to be compact). By definition a Kahler-Einstein metric in this singular context simply means a Kahler-Einstein on the regular locus of X with volume equal to the algebraic volume of K (X) , i.e. the top intersection number of K (X) . We also show that such a metric is uniquely determined and extends to define a canonical positive current in c (1)(K (X) ). Combined with recent results of Odaka our main result shows that X admits a Kahler-Einstein metric iff X is K-stable, which thus confirms the Yau-Tian-Donaldson conjecture in this general setting of (possibly singular) canonically polarized varieties. More generally, our results are shown to hold in the setting of log minimal varieties and they also generalize some prior results concerning Kahler-Einstein metrics on quasi-projective varieties.

Genotype by Environment Interaction (G x E) and Grain Yield Stability Analysis of Ethiopian Linseed and Niger Seed Varieties

General Background : Niger seed [( Guizotia abyssinica (L.F.) Cass.), 2n = 30] and Linseed [( Linum usitatissimum L.), n=15] are indigenous oil crops of Ethiopia. Over many years, there are a few Linseed and Niger seed varieties developed and released through intensive breeding and genetics research program in Ethiopia. However, whether these varieties are stable, adaptable to the environments of Western Ethiopia and similar agro-ecologies are not clear. Objectives: The objectives of the study were to (i) assess genotype by environment interaction (G x E) and (ii) identify stable and adaptable Linseed and Niger seed varieties for specific and wide adaptions. Materials and methods : All Niger seed and Linseed released varieties of Ethiopia between the years 1984 and 2008 were tested for multi-locations and years. Independent experiments of linseed and Niger seed varieties were evaluated in Randomized Complete Block Design replicated three times. Eight varieties of Linseed with one local variety were evaluated at Arjo, Gute and Shambu locations. In addition, five Niger seed varieties including one local variety were tested at Bako, Gute and Shambu locations. Summary of the result and application of the findings: The seed yields ranged between 0.898 tons ha-1 and 1.575 tons/ha for Linseed and between 0.600 tons ha-1 and 0.690 tons ha-1 for Niger seed. Analysis of variance using additive main effects and multiplicative interactions (AMMI) model revealed significant differences (pG0.01) for genotype, environment, genotype x environment interaction and interaction principal component (IPCA1) for Linseed, while only environment was found to be significantly different for Niger seed. Based on AMMI analysis, Kulumsa-1 was the best yielding, stable and widely adapted, while CI-1525 and Berene were high yielding but unstable and specifically adapted Linseed varieties to high yielding environments. Belay 96, Chilalo, Tole and CI-1652 were moderately stable and adapted to high yielding environments. Among Niger seed varieties, Shambu-1 and Esete-1 had comparable seed yield with moderately stable for the tested environments whereas Kuyu and local variety were unstable and not adopted to the testing environments. Key words/phrases: Adapted variety, Additive main effect and multiplicative interaction (AMMI), Genotype x environment (G x E) interaction, Stable variety

Exploitation of yield stability in barley.

Analyses of registration trials of winter barley suggested that yield and yield stability can be enhanced by developing hybrid instead of line varieties. Yield stability is central to cope with the expected increased frequency of extreme weather conditions. The objectives of our study were to (1) examine the dimensioning of field trials needed to precisely portray yield stability of individual winter barley (Hordeum vulgare L.) genotypes, (2) compare grain yield performance and yield stability of two-rowed lines with those of six-rowed lines and hybrids, and (3) investigate the association of various agronomic traits with yield stability. Static and dynamic yield stability as well as grain yield performance was determined in five series of 3-year registration trials of winter barley in Germany. Each series included 4 or 5 six-rowed hybrids, 40-46 six-rowed inbred lines, as well as 42-49 two-rowed inbred lines. The genotypes were evaluated in 10-45 environments, i.e. year-by-location combinations. We found that precise assessment of yield stability of individual genotypes requires phenotyping in at least 40 test environments. Therefore, selection for yield stability is not usually feasible since the required number of test environments exceeds the common capacity of barley breeding programs. Also, indirect improvement of yield stability by means of agronomic traits seemed not possible since there was no constant association of any agronomic trait with yield stability. We found that compared with line varieties, hybrids showed on average higher grain yield performance combined with high dynamic yield stability. In conclusion, breeding hybrid instead of line varieties may be a promising way to develop high yielding and yield stable varieties.

Genotype X Environment Interaction and Stability Analysis in Kenaf (Hibiscus cannabinus L.) for Growth and Yield Performances in Southwest Nigeria

Genotype x environment interaction and stability analysis for growth and yield performances of kenaf (Hibiscus cannabinus L.) were carried out by growing ten varieties of kenaf (a newly developed kenaf variety; Ife Ken DI 400 alongside with other two improved varieties developed in Nigeria, two exotic improved varieties, four lines and one local). The trials were conducted in the three research stations of the Institute of Agricultural Research and Training, Obafemi Awolowo University, Moor Plantation Ibadan. The research stations are located at Ikenne (high rain forest agro-ecology), Ibadan (transitional rain forest agro-ecology) and Ilora (derive savanna agro-ecology) in 2007 and 2008. Combined analysis of variance showed that there were significant (P < 0.05) differences among the cultivars, locations, cultivar x year and year x location interactions for the traits investigated. Influence of year and cultivar x location and cultivar x location x year were not significant. There were significant differences in plant height, basal diameter, fiber yield and core yield among the cultivars, significant differences among locations in fiber yield and core yield and there were significant cultivar x year and year x location interactions for fiber yield and core yield. For stability analysis, the most stable cultivars in fiber yield and core yield were the improved varieties. For the fiber yield and core yield the most stable variety among the improved varieties was Ife Ken DI 400, followed by Ife Ken 400 and Ife Ken 100, while the fourth ranked stabled variety was Cuba 108. The most unstable improved variety was Tainung-1. Among the lines, AC 313-293 was most stable; it ranked seventh, while G 45-2 was regarded as most unstable cultivar followed by Local 35 and 2QQ 174 that ranked eighth, ninth and tenth respectively.

New spring malting barley varieties: NS Mile and NS Marko

Breeding program at the Institute of Field and Vegetable Crops is directed to the development of new barley cultivars with a high and stable yield, good malting quality and high resistance abiotic and biotic stress. As a result of this work, two new varieties of spring malting barley NS Mile and NS Marko were developed in the 2012. The two-year trial of Commission for the registration of varieties, Republic of Serbia, showed that the NS Marko and NS Mile are distinct, uniform and stable varieties, and that on average they had significantly higher yield and better quality than standard variety for all the test sites and all years. NS Marko and NS Mile are new early varieties of NS malting barley that are characterized by high genetic potential for yield, which is more than 9 t ha-1, as well as by high quality, especially high content of malt extract and lower protein content compared to standard cultivar.

Stability for Yield and its Component Traits in Durum Wheat (Triticum durumDesf.)

Fifty genotypes of durum wheat were evaluated over four diverse environments for grain yield and its component traits (tiller number, grains/spike and 100 grain weight). Genotype × environment interaction was found significant for all the traits except 100 grain weight. Further, linear component of G × E interaction was significant for 100 grain weight suggesting that the variation in performance of different genotypes could be predicted. The genotypes IDYT-CA-05-47, NI 146, PDW 215, IDYN 46 and IDYN 49 were found to desirable and stable across the environments for grain yield. Thus, these genotypes could be included in the hybridization programme to converge the stability characteristics of grain yield for the development of a stable variety adapted to wider range of environments.

Combining Ability for Kernel Starch Content in Maize Synthetic Populations Obtained from Local Populations

Synthetic populations of maize (Zea mays L) are low-cost and stable varieties, obtained by cross pollination of a group of inbred lines, local population or hybrids. The main advantage of these populations is that the heterosis does not diminish significantly in F2. In order to complete the research on the combining ability of maize synthetic populations, the objective of this work was to study seven maize synthetic populations, determining their general combining ability (GCA) and specific combining ability (SCA) for kernel starch content, as well as their potential as source populations in breeding programmes.To achieve the proposed objectives, we studied top cross hybrids of the type “inbred line x synthetic population” resulted from the crossing between seven synthetic maize populations and four early inbred lines used as tester. For all experimental conditions, the differences between genotypes were statistically assured for kernel starch content. The experimental years and testing locations have provided conditions for differentiation of genotypes for starch content and interactions between the environment and genotypes were statistically significant, indicating dependence of starch content on environmental conditions. The additive effects for starch content provided by GCA were high for Tu SRR 5DR(6I)(5) and Tu SRR 5D (2I)(2). Non additive effects, corresponding to SCA were high for the following hybrid combinations: TC 233 x TuSyn 1 (3), CO 255 x Tu SRR 5D (2I)(2) and TC 209 x Tu SRR 5DR(6I)(5). In the case of synthetic maize populations, the determinism of starch is influenced equally by GCA and SCA.

Moduli of products of stable varieties

AbstractWe study the moduli space of a product of stable varieties over the field of complex numbers, as defined via the minimal model program. Our main results are: (a) taking products gives a well-defined morphism from the product of moduli spaces of stable varieties to the moduli space of a product of stable varieties; (b) this map is always finite étale; and (c) this map very often is an isomorphism. Our results generalize and complete the work of Van Opstall in dimension$1$. The local results rely on a study of the cotangent complex using some derived algebro-geometric methods, while the global ones use some differential-geometric input.

English

The aim of the present study is to develop phenotypically stable varieties for those soils that are contaminated with mercury or cobalt. This is a novel report about their ability to grow in the contaminated soil. The benefit of this technology is the potential for low cost remediation. Highly significant differences have been observed among the varieties of &nbsp;Linum usitatissimum for all the characters in all the treatment or environment. There has been considerable amount of variability for all the characters in all the treatments. The 10-5 M HgCl2 treatment shows the inhibitory effect in all the varieties and there is no further seedling establishment after seed germination. The highest toxic effect has been observed for the seedling vigour and seed vigour index. The 10-5 M HgCl2 concentration is the last limit of tolerance in plants while 10-4 M CoCl2 could be the last tolerance limit and there may be a specific gene in plants which monitor the toxicity level or tolerance capacity. The maximum magnitude of positive correlation coefficient has been found between seedling fresh and dry weight and negative for 1000 seed weight and germination rate index. The seedling length exerts maximum positive direct effect on seedling vigour followed by absolute seedling water content. &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Key words: &nbsp;Linum, seed germination, CoCl2, HgCl2, variability, correlation, path. &nbsp;

Stability in Performance of Normal and Nutritionally Enhanced Highland Maize Hybrid Genotypes in Eastern Africa

Maize (Zea mays L.) is a major crop in Eastern Africa in terms of production, consumption and income generation. Although highland ecologies in Eastern Africa have high potential for maize production, few varieties have been developed. Breeding efforts have been also concentrated on Quality Protein Maize (QPM) as a viable and cheaper method to alleviate malnutrition. Twenty conventional and 20 QPM three-way hybrid genotypes were developed and evaluated in a randomized block design across 11 and 8 environments in Ethiopia, Kenya, Rwanda and Uganda in 2010. The objective was to identify superior and stable varieties from genotypes. Data were recorded on major agronomic traits (grain yield t ha-1). Additive main effects and multiplicative interactions (AMMI) statistical model was used to assess stability in performance for grain yield. Combined analysis of variance across environments indicated highly significant differences among non-QPM and QPM genotypes. Variations due to environment and genotypexenvironment (GxE) were suggesting genotypes performed differently across environments. Environments of Gisozi, Holleta, Kongoni and Kapchorwa were favourable and stable while Kulumsa was favourable but unstable. Other environments were of medium to low potential. The AMMI analysis ranked 5 non-QPM genotypes were with above-average yield (6.34 t ha) and 8 for stability performance across environments. While for QPM 3 genotypes were yielded better than best check (6.941 ha) and 7 genotypes were stable. Genotype 9 (7.15 t ha) was the only non-QPM genotype with yield better than the best check across environments. The information obtained will help to streamline highland maize testing programs in the region.