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Oct 2023 DOI 10.14302/issn.2639-3166.jar-23-4463
Haroun M. Adam AbubakerCorresponding author
Genotype by environment (GE) interaction is considered to be among the major factors limiting the efficiency of breeding programs.Five chickpea genotypes were evaluated to study their adaptability and stability in eight environments of Sudan. The experiments were carried out in randomized complete block design (RCBD) with four replications in four locations in over two years (2017/2018 and 2018/2019).Stability was estimated using additive main effects and multiplicative interaction (AMMI) model.A Combined analysis of variance showed significant effects of genotypes, locations, years and their interactions on seed yield. Mean seed yield ranged between 1.88 and 1.45 t ha-1 for the genotypes FLIP 08-59 C and FLIP 09-187 C, respectively. The genotype FLIP 08-59 C gave the highest average seed yield and out-yielded the two checks, Shiekh Mohamed and Burgeig by 9.5% and 10.1%, respectively. The newly introduced (FLIP 08-59 C) showed non- significant differences in earliness as compared to the other two standard checks resistant to fusarium wilt disease and with good seed weight. The statistical analysis showed that genotype (G), environment (E) and their interaction (GEI) had highly significant (P ≤ 0.001) effect on seed yield. It also revealed that environmental differences accounted for 90.2% of the total variation. The results of data analysis displayed that the percentages of seed yield by environment, genotype and genotype environment interaction were 90.2%, 3.6% and 6.3%, respectively. The IPCA 1 and IPCA 2 axes (Principal Components) were highly significant P ≤ 0.001). The model for seed chickpea yield stability (the Additive Main Effect and Multiplicative Interaction (AMMI) model) showed that the G1 (FLIP 08-59 C) was adapted, high yielding and considered as stable genotype for Gezira, River Nile and Northern States of Sudan. In addition, this genotype is early flowering with non-significant differences in earliness as compared to the two checks and with good seed weight. Therefore, the above mentioned genotype FLIP 08-59 C could be recommended as commercially stable and high yielding cultivar and/or incorporated as breeding stocks in any future breeding programs aiming to produce high yielding genotypes of chickpea.
Sep 2018
Giammarino MauroCorresponding author
Department of Prevention, Asl CN 1, Veterinary Service, Area Animal Sanity, Piazza Luigi Gallo 1, 12035 Racconigi (CN), Italy.
Groups of wild juvenile and adult mallard ducks were captured, ringed, measured, while, juvenile ones already ringed, were remeasured on a subsequent recapture between March and September over a period of 7 years, at a site in Piedmont (Italy). Measurements cover both the rates and the pattern of development of 4 morphological features (head-and-bill-length, bill-length, tarsus-length, and weight). Juveniles were examined and their measurements were compared with the asymptotic value obtained from adults’ measures. A functional data analysis growth model was fitted to data and it yielded plausible quantitative estimates. Tarsus appears to reach the asymptote faster than the other morphological features in this population. Finally, a functional principal components analysis was performed to discriminate sex in growing Mallard ducks.
Jul 2018 DOI 10.14302/issn.2639-3166.jar-18-2083
A. Okasha SalahCorresponding author
Agronomy Dept, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt
This study was conducted to determine drought tolerant indices of some sugar beet genotypes under water stress and non-stress conditions. Nine sugar beet (Beta Vulgaris L.) genotypes were tested in a Split-plot experiment based on a randomized complete block design in three replications under three levels of water stress 100%, 75% and 50% from plant requirements at the experimental farm Faculty of Agriculture, Suez Canal University, Ismailia, Egypt during 2015/ 2016 and 2016 / 2017 seasons. Twelve drought tolerance indices were used in this study, stress sensitivity index (SSI), stress tolerance (TOL), mean productivity (MP), geometric mean (GMP), harmonic mean (HM),yield stability index (YSI), yield index (YI), stress tolerance index (STI), sensitivity drought index (SDI), relative drought index (RDI), drought response index (DI) and stress susceptibility percentage index (SSPI). GMP, MP and STI were more informative towards classification of better or superior genotypes with respect to tolerant and sensitive groups. The results showed that the genotypes with high STI, GMP and MP values were suitable for cultivation under drought stress and non-stress environments. Both Yp and Ys of root yield in the control-50% analysis had significantly positive correlated (P value<0.05) with MP, GMP, YI, HM and DI, This indicates that these indices were more effective in identifying high yielding genotypes under drought stress as well as non-stress conditions.Principal components analysis showed that the first two components in the control-50% analysis, genotype Bts 1237 and Temar were identified as the most stable high yielding genotypes in both environments