scholarly journals The performance of true seed shallot lines under different environments of Ethiopia

2014 ◽  
Vol 59 (2) ◽  
pp. 129-139 ◽  
Author(s):  
Aklilu Shimeles
Keyword(s):  
Regression Coefficient ◽  
Small Deviation ◽  
Environmental Index ◽  
Combined Analysis ◽  
Genotype By Environment ◽  
Environment Effects ◽  
True Seed ◽  
The Mean ◽  
Growing Conditions ◽  
Bulb Yield

Seven true seed shallot lines were evaluated for 3 years at 3 locations to determine their performance and stability. Stability differences were assessed on the basis of linear regression of the lines on environmental index and on deviation from linear function along with the mean yield. The combined analysis showed that bulb yield over 9 environments ranged from 15.1 to 17.5 t ha-1 with overall mean yield of 16.5 t ha-1, and lines Vethalam, Tropix, Dz-94 and Athlas gave the highest mean yield. The combined analysis of variance showed significant (p<0.05) genotype and genotype by environment effects on bulb yield. The regression coefficient for bulb yield ranged from 0.72 to 1.36. The regression coefficient of two high yielding lines (Vethalam and Athlas) was above 1, and was higher in environments where growing conditions were favorable. High and significant deviations were obtained for lines Tropix and Athlas and these lines were found unstable to change in environment. However, line Tropix showed specific adaptation to low yielding environments of Kulumsa and Melkassa. The best line Vethalam with a small deviation from regression was found widely adaptable to different environments and it was released with local name ?Yeras? to be grown in Rift Valley and similar areas in Ethiopia.

scholarly journals Simulation of Heavy Metals Migration in Soil-Wheat System of Mining Area

2019 ◽  
Vol 16 (14) ◽  
pp. 2550 ◽  
Author(s):  
Aman Fang ◽  
Jihong Dong ◽  
Ru Zhang
Keyword(s):  
Heavy Metals ◽  
Regression Coefficient ◽  
Quality Standards ◽  
Mining Area ◽  
Control Site ◽  
National Guidelines ◽  
The Mean ◽  
Cr Concentration ◽  
Relationship Of ◽  
Soil Wheat

Heavy metals in the soil of mining areas have become a primary source of pollution, which could cause deleterious health effects in people exposed through soil-plant systems via multi-pathways. A long-term field experiment under natural conditions was carried out to explore the distribution characteristic and migration law of heavy metals in a soil-wheat system of a mining area in Xuzhou. According to the second level standard of environmental quality standards for soils of China (GB 15618-1995), 30.8 g of CrCl3·6H2O, 8.3 g of Pb(CH3COO)2·3H2O, and 16.5 g of ZnSO4·7H2O were added into the soil of three experimental sites, respectively. The other experimental site with no additional compounds was used as the control site. The Cr, Pb, and Zn concentrations in the soil-wheat system were counted and their corresponding migration models were constructed. From 2014 to 2017, the mean concentrations of Cr (49.09 mg·kg−1), Pb (20.08 mg·kg−1), and Zn (39.11 mg·kg−1) in the soil of the addition sites were higher than that of the control site. The mean concentrations of Cr, Pb, and Zn in wheat of the addition sites were greater than that of the control site with the values of 3.29, 0.06, and 29 mg·kg−1. In comparison, the Cr, Pb, and Zn concentrations in the soil of all experimental sites were lower than the second level standard of environmental quality standards for soils of China (GB 15618-1995), whereas the Cr concentration exceeded its corresponding soil background value of Xuzhou in 2017. The Pb concentration in soil of the addition site was greater than its corresponding background value from 2014 to 2016. The Pb and Zn concentrations in wheat of all experimental sites were lower than the national hygienic standard for grains of China (GB2715-2005) and the national guidelines for cereals of China (NY 861-2004), but the Cr concentration significantly exceeded the national guidelines for cereals of China (NY 861-2004). By constructing the Identical-Discrepant-Contrary (IDC) gray connection models, the result showed that there was a non-linear relationship of Cr, Pb, and Zn concentrations in the soil-wheat system, and the absolute values of most correlation coefficients r were lower than 0.5 and the values of greyness f G ( r ) were more than 0.5. The curvilinear regression models could not reflect the relationship of Cr, Pb, and Zn concentrations in the soil-wheat system with the regression coefficient r 2 values far less than 1. Due to the values of regression coefficient r 2 being close to 1, this study suggested that the allocation estimation models could be used for simulating the Cr, Pb, and Zn migration in the soil-wheat system of a mining area in Xuzhou.

Minimum Effective Rate of Chlorimuron and Imazaquin Applied to Common Cocklebur (Xanthium strumarium)

1989 ◽  
Vol 3 (1) ◽  
pp. 126-130 ◽  
Author(s):  
William L. Barrentine
Keyword(s):  
Field Experiment ◽  
Moisture Stress ◽  
Effective Rate ◽  
Xanthium Strumarium ◽  
Regression Analyses ◽  
Probit Regression ◽  
The Mean ◽  
Growing Conditions

A field experiment was conducted in 1986 and 1987 to determine the minimum effective rate (MER)3of imazaquin and chlorimuron applied postemergence to common cocklebur. MER is defined as the quantity required to provide at least 90% control. Based on probit regression analyses, the mean calculated MERs of imazaquin and chlorimuron for 2-leaf common cocklebur were 27.5 and 4.5 g ai/ha, respectively. Under optimum growing conditions, the calculated MERs of imazaquin and chlorimuron for 6-leaf common cocklebur were 34 and 4.6 g/ha, respectively. When applied to 6-leaf plants under slight moisture stress, the calculated MERs for imazaquin and chlorimuron were 54 and 17.4 g/ha, respectively.

Stability of fenugreek (Trigonella foenum-graecum L.) genotypes for terminal heat and water stress

2015 ◽  
Vol 38 (5) ◽  
Author(s):  
Suresh Kumar Meena ◽  
E. V. Divakara Sastry ◽  
S. S. Rajput ◽  
Yogesh Pandey
Keyword(s):  
Seed Yield ◽  
Regression Coefficient ◽  
Block Design ◽  
Stability Parameters ◽  
Trigonella Foenum Graecum ◽  
Randomized Block Design ◽  
Ammi Analysis ◽  
Component Traits ◽  
The Mean ◽  
Irrigation Levels

Thirty genotypes of fenugreek (<italic>Trigonella foenum-graecum</italic> L.) were evaluated over four environments in randomized block design with 3 replications to estimate stability parameters of seed yield and its important component traits. The environments were created by changing the dates of sowing and irrigation levels. The genotypes interacted with the environments significantly indicating non linear response of genotypes to environments. Simple correlations between seed yield and other traits indicated that pods per plant and the test weight are the two important component traits. Stability analysis indicated difference in stability among the genotype for seed yield and the component traits. A positive correlation was noted between the regression coefficient and the mean seed yield of the genotypes, thus hypothesizing that higher yielding genotypes were better suited to better environments. The results of AMMI analysis corroborated with the results obtained from stability anlaysis, although AMMI analysis provided a better chance to delineate the genotypes and environments. Genotypes UM-137, UM-128, UM-322 and RMt-1 are found relatively stable for seed yield.

FLAXSIBILITY OF POTATO VARIETIES IN THE URALS STEPPE ZONE

2016 ◽  
Vol 1 (3) ◽  
pp. 20-22 ◽  
Author(s):  
Аминова ◽  
Evgeniya Aminova ◽  
Мушинский ◽  
Aleksandr Mushinskiy ◽  
Герасимова ◽  
...  
Keyword(s):  
Stability Analysis ◽  
Regression Coefficient ◽  
Factor Model ◽  
Steppe Zone ◽  
Progressive Increase ◽  
The Urals ◽  
Potato Varieties ◽  
Ecological Flexibility ◽  
Growing Conditions ◽  
The Stability

The purpose of research is to identify potato varieties with high ecological flexibility and stability in the conditions of steppe zone of the Urals. The experience was laid by one-factor circuit in 3-fold repetition. The studies were conducted for middle and middle-early varieties of potatoes domestic and foreign selection. We define the parameters of their ecological plasticity and stability analysis using two-factor model (conditions and years). In 3-year data were allocated potato varieties – Artemis (58.9 t/ha), Aerrow (51.6 t/ha), Riviera (51.1 t/ha), Romano (55.2 t/ha). The regression coefficient ranged from 0.54 to 2.59, the stability coefficients vary from 0.20 to 49.04. It was found that the regression coefficient is significantly greater than one, indicating that the progressive increase in yield under the influence of improved growing conditions in such varieties as: Rainbow (Ri 2.19), Sail (Ri 2.59), Memory Kovalenko (Ri 2.41) Tarasov (Ri 2.05), Karatop (Ri 2.19) – varieties of intensive type. Revealed grade plastic – Nevsky, Spiridon, Romano, Aerrow, Scarlett Red, Riviera, Curator (Ri=0.70-1.08).

Voluntary food intake in relation to body weight among British breeds of cattle

1986 ◽  
Vol 42 (1) ◽  
pp. 11-18 ◽  
Author(s):  
St C. S. Taylor ◽  
A. J. Moore ◽  
R. B. Thiessen
Keyword(s):  
Body Weight ◽  
Food Intake ◽  
Linear Regression ◽  
Regression Coefficient ◽  
Natural Logarithm ◽  
The Mean ◽  
Voluntary Intake ◽  
Relationship Of ◽  
The Relationship ◽  
Voluntary Food Intake

ABSTRACTVoluntary food intake and body weight were examined over 4-week intervals between 14 and 70 weeks of age in 306 females from 25 British breeds of cattle. At each age, the relationship of the natural logarithm of voluntary food intake to that of body weight was examined by linear regression both within and between breeds.Of the total variation in voluntary food intake, the proportion accounted for by body weight was extremely high between breeds (phenotypically, 0·80 or more; genetically 0·88 or more, at most ages) but phenotypically low within breeds (0·33 or less). The mean voluntary intake of a breed at any age could be predicted from its mean body weight at the same age with a coefficient of variation (CV) among breeds that declined with age from 0·08 to 0·04. Within breeds, the corresponding CV for individual intake was between 0·12 and 0·15 beyond 9 months of age, and even higher at early ages.Within breeds, the regression coefficient of log intake on log body weight was close to the value of 0·7 at all ages. Between breeds, it was over 0·8 at early ages, declining to about 0·7 beyond 1 year of age. Thus, genetically larger breeds voluntarily consumed relatively more food at early ages compared with later ages. Breed size should therefore be taken into account when recommending food intake requirements. Breed deviations for high and low appetite are discussed.

Temperature, CO2 and the growth and development of wheat: Changes in the mean and variability of growing conditions

1996 ◽  
Vol 33 (3) ◽  
pp. 351-368 ◽  
Author(s):  
D. J. Moot ◽  
A. L. Henderson ◽  
J. R. Porter ◽  
M. A. Semenov
Keyword(s):  
Growth And Development ◽  
The Mean ◽  
Growing Conditions

The use of an AMMI model and its parameters to analyse yield stability in multi-environment trials

2008 ◽  
Vol 146 (5) ◽  
pp. 571-581 ◽  
Author(s):  
N. SABAGHNIA ◽  
S. H. SABAGHPOUR ◽  
H. DEHGHANI
Keyword(s):  
Stability Analysis ◽  
Crop Improvement ◽  
Principal Component ◽  
Environmental Variance ◽  
Combined Analysis ◽  
Genotype By Environment ◽  
Breeding Programmes ◽  
Ammi Model ◽  
Index Measure ◽  
Stability Statistics

SUMMARYGenotype by environment (G×E) interaction effects are of special interest for breeding programmes to identify adaptation targets and test locations. Their assessment by additive main effect and multiplicative interaction (AMMI) model analysis is currently defined for this situation. A combined analysis of two former parametric measures and seven AMMI stability statistics was undertaken to assess G×E interactions and stability analysis to identify stable genotypes of 11 lentil genotypes across 20 environments. G×E interaction introduces inconsistency in the relative rating of genotypes across environments and plays a key role in formulating strategies for crop improvement. The combined analysis of variance for environments (E), genotypes (G) and G×E interaction was highly significant (P<0·01), suggesting differential responses of the genotypes and the need for stability analysis. The parametric stability measures of environmental variance showed that genotype ILL 6037 was the most stable genotype, whereas the priority index measure indicated genotype FLIP 82-1L to be the most stable genotype. The first seven principal component (PC) axes (PC1–PC7) were significant (P<0·01), but the first two PC axes cumulatively accounted for 71% of the total G×E interaction. In contrast, the AMMI stability statistics suggested different genotypes to be the most stable. Most of the AMMI stability statistics showed biological stability, but the SIPCF statistics of AMMI model had agronomical concept stability. The AMMI stability value (ASV) identified genotype FLIP 92-12L as a more stable genotype, which also had high mean performance. Such an outcome could be regularly employed in the future to delineate predictive, more rigorous recommendation strategies as well as to help define stability concepts for recommendations for lentil and other crops in the Middle East and other areas of the world.

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