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Prediction of Hevea progeny performance in the presence of genotype-environment interaction
Gon?alves, Paulo de Souza;Moraes, Mário Luiz Teixeira de;Silva, Marcelo de Almeida;Gouvêa, Lígia Regina Lima;Aguiar, Adriano Tosoni da Eira;Costa, Reginaldo Brito da;
Brazilian Archives of Biology and Technology , 2009, DOI: 10.1590/S1516-89132009000100004
Abstract: twenty two open-pollinated hevea progenies from different parental clones of the asian origin were tested at five sites in the northwestern s?o paulo state brazil to investigate the progeny girth growth, rubber yield, bark thickness and plant height. except for the rubber yield, the analysis of variance indicated highly significant (p<0.01) genotype x environment interaction and heterogeneity of regressions among the progenies. however, the regression stability analysis identified only a few interacting progenies which had regression coefficients significantly different from the expected value of one. the linear regressions of the progeny mean performance at each test on an environmental index (mean of all the progenies in each test) showed the general stability and adaptability of most selected hevea progenies over the test environments. the few progenies which were responsive and high yielding on different test sites could be used to maximize the rubber cultivars productivity and to obtain the best use of the genetically improved stock under different environmental conditions.
Variability of some traits of flax seed in respect to genotype and climatic conditions  [PDF]
Maleti? Radojka,Jev?ovi? Radosav
Journal of Agricultural Sciences , 2006, DOI: 10.2298/jas0601007m
Abstract: Beside its multiple use in oil producing and feed industry, flax seed is used also in pharmaceutical industry as additional medicinal component, whether as mono component or in tea mixtures. Results of a two-year cultivation of several flax genotypes are analyzed. The highest yield of seed in both study years was achieved in genotype "Z" and the lowest in standard cultivar "Mira". In regard to germination energy and total germination, the best value was determined for genotype "B" and the lowest for standard cultivar "Mira". The greatest swelling of flax seeds was established for genotype "B", and the least in the case of genotype "Z". Climatic conditions in the year of cultivation had effects on yield and quality of flax seed. During 2001. the year with high rainfall, higher yields were produced in all tested genotypes, and better germination energy, total germination and mass of 100 seeds established. In seed obtained in 2002, when average temperatures were higher, number of swollen seeds was higher. .
Variability of major traits of marigold seed in respect of genotype and climatic conditions  [PDF]
Jev?ovi? Radosav,Maleti? Radojka O.
Journal of Agricultural Sciences , 2004, DOI: 10.2298/jas0401033j
Abstract: The results of the two-year comparative research of qualitative and quantitative traits of marigold seed of different genotypes in regard to the standard cultivar were analyzed. The highest yield of seed in both study years was registered in genotype "King orange", and the lowest in genotype "R". Concerning the quality of seed, that is, germination energy and total germination, the best results were established for genotype "King orange" and the poorest for genotype "R" in both study years. The highest absolute mass was registered in domestic cultivar "Domestic orange". Climatic conditions had great influence on yield and quality of marigold seed. In the first study year, with 2.5 times higher water sediment during the vegetation period, seed yield in all genotypes was higher compared to the second study year. Also, absolute mass of seed of all genotypes was higher in the first study year. However, germination energy and total germination for all genotypes was better in the second year, when the sum of temperatures during the vegetation period was 37580C compared to the first year when the sum of temperatures recorded was 35230C.
Genotype-environment interaction and phenotypic stability for girth growth and rubber yield of Hevea clones in S?o Paulo State, Brazil
Gon?alves, Paulo de Souza;Bortoletto, Nelson;Martins, Antonio Lúcio Mello;Costa, Reginaldo Brito da;Gallo, Paulo Boller;
Genetics and Molecular Biology , 2003, DOI: 10.1590/S1415-47572003000400007
Abstract: the best-yielding, best vigour and most stable hevea clones are identified by growing clones in different environments. however, research on the stability in hevea brasiliensis (willd. adr. ex juss.) muell.-arg. is scarce. the objectives of this work were to assess genotype-environment interaction and determine stable genotypes. stability analysis were performed on results for girth growth and rubber yield of seven clones from five comparative trials conducted over 10 years (girth growth) and four years (rubber yield) in s?o paulo state, brazil. stability was estimated using the eberhart and russell (1966) method. year by location and location variability were the dominant sources of interactions. the stability analysis identified gt 1 and ian 873 as the most stable clones for girth growth and rubber yield respectively since their regression coefficients were almost the unity (b = 1) and they had one of the lowest deviations from regressions (s2di). their coefficient of determination (r2) was as high as 89.5% and 89.8% confirming their stability. in contrast, clones such as pb 235, pr 261, and rrim 701 for girth growth and clones such as gt 1 for rubber yield with regression coefficients greater than one were regarded as sensitive to environment changes.
Genotype-environment interaction and phenotypic stability for girth growth and rubber yield of Hevea clones in S o Paulo State, Brazil
Gon?alves Paulo de Souza,Bortoletto Nelson,Martins Antonio Lúcio Mello,Costa Reginaldo Brito da
Genetics and Molecular Biology , 2003,
Abstract: The best-yielding, best vigour and most stable Hevea clones are identified by growing clones in different environments. However, research on the stability in Hevea brasiliensis (Willd. Adr. ex Juss.) Muell.-Arg. is scarce. The objectives of this work were to assess genotype-environment interaction and determine stable genotypes. Stability analysis were performed on results for girth growth and rubber yield of seven clones from five comparative trials conducted over 10 years (girth growth) and four years (rubber yield) in S o Paulo State, Brazil. Stability was estimated using the Eberhart and Russell (1966) method. Year by location and location variability were the dominant sources of interactions. The stability analysis identified GT 1 and IAN 873 as the most stable clones for girth growth and rubber yield respectively since their regression coefficients were almost the unity (b = 1) and they had one of the lowest deviations from regressions (S2di). Their coefficient of determination (R2) was as high as 89.5% and 89.8% confirming their stability. In contrast, clones such as PB 235, PR 261, and RRIM 701 for girth growth and clones such as GT 1 for rubber yield with regression coefficients greater than one were regarded as sensitive to environment changes.
Genotype-environment interaction and the number of test sites for the genetic improvement of rubber trees (Hevea) in S?o Paulo State, Brazil
Costa, Reginaldo Brito da;Resende, Marcos Deon Vilela de;Araujo, Antonio José de;Gon?alves, Paulo de Souza;Martins, Antonio Lúcio Mello;
Genetics and Molecular Biology , 2000, DOI: 10.1590/S1415-47572000000100033
Abstract: the present study quantifies the possible genotype-environment interactions and determines the ideal number of test sites for rubber trees [hevea brasiliensis (willd ex adr. de juss.) muell arg] in the plateau region of s?o paulo state. the study was based on the genetic correlation among progenies at three different sites and on estimates of genetic gains with indirect selection of rubber trees. twenty-two half-sib progenies were planted at the jaú, pindorama and votuporanga experimental stations using random blocks with five replications and 10 plants per plot. at three years of age, the plants were evaluated for their total number of latex ring vessels (nr), rubber production (rp), bark thickness (bt) and girth (sg). there was significant genetic variability in the characters rp, sg and bt, mainly among progenies from pindorama and votuporanga. the effects of genotype-site interactions were significant for rp and sg. the finding of significant interactions was not a complicating factor because of the large genetic correlation detected. these results indicate that the use of two sites is more profitable when the gains in efficiency of selection are greater than 10%. thus, pindorama and votuporanga will satisfactorily attend the studied region.
Genotype-environment interaction and the number of test sites for the genetic improvement of rubber trees (Hevea) in S o Paulo State, Brazil  [cached]
Costa Reginaldo Brito da,Resende Marcos Deon Vilela de,Araujo Antonio José de,Gon?alves Paulo de Souza
Genetics and Molecular Biology , 2000,
Abstract: The present study quantifies the possible genotype-environment interactions and determines the ideal number of test sites for rubber trees [Hevea brasiliensis (Willd ex Adr. de Juss.) Muell Arg] in the plateau region of S o Paulo State. The study was based on the genetic correlation among progenies at three different sites and on estimates of genetic gains with indirect selection of rubber trees. Twenty-two half-sib progenies were planted at the Jaú, Pindorama and Votuporanga experimental stations using random blocks with five replications and 10 plants per plot. At three years of age, the plants were evaluated for their total number of latex ring vessels (NR), rubber production (RP), bark thickness (BT) and girth (SG). There was significant genetic variability in the characters RP, SG and BT, mainly among progenies from Pindorama and Votuporanga. The effects of genotype-site interactions were significant for RP and SG. The finding of significant interactions was not a complicating factor because of the large genetic correlation detected. These results indicate that the use of two sites is more profitable when the gains in efficiency of selection are greater than 10%. Thus, Pindorama and Votuporanga will satisfactorily attend the studied region.
A Recent Study on the Relationship between Global Radiative Forcing and Global Annual Climatic Variability  [PDF]
Yehia Yehia Hafez, Mansour Almazroui
Atmospheric and Climate Sciences (ACS) , 2015, DOI: 10.4236/acs.2015.51003
Abstract:

The present paper investigates the relationship between the global radiative forcing (GRF) and global annual climatic variability. The relation between the GRF and global annual changes in the operational weather and climatic parameters is uncovered. There are several datasets which have been used to challenge this goal. The NCEP/NCAR Reanalysis dataset of several meteorological elements, such as air temperature, wind, surface pressure, outgoing long wave radiation, precipitation rate and geopotential height at level 500 hPa, etc. for the globe for the period (1948-2012), has been used. Furthermore, the GRF data for greenhouse gases through the period (1979-2010) has been used. Also, datasets of climatic indices NAO, SOI, El Nino 3.4 and SST during the period (1948-2012) have been used through this study. Time series analysis, anomaly and correlation coefficient technique methods have been used to analyze the datasets. The results reveal that there is an outstanding positive correlation coefficient (more than +0.80) between GRF and the global annual weather elements of surface air temperature, temperature and geopotential height at level 500 hPa, precipitation rate and sea surface temperature. CO2 has a significant correlation coefficient (+0.89) with the outcomes longwave radiation and sea surface temperature. There is a significant relationship between the global annual variability of weather and climatic elements and GHGs, global warming and climatic indices, NAO, SOI, El Nino 3.4 and SST.

Effects of Climatic Factors and Ecosystem Responses on the Inter-Annual Variability of Evapotranspiration in a Coniferous Plantation in Subtropical China  [PDF]
Mingjie Xu, Xuefa Wen, Huimin Wang, Wenjiang Zhang, Xiaoqin Dai, Jie Song, Yidong Wang, Xiaoli Fu, Yunfen Liu, Xiaomin Sun, Guirui Yu
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0085593
Abstract: Because evapotranspiration (ET) is the second largest component of the water cycle and a critical process in terrestrial ecosystems, understanding the inter-annual variability of ET is important in the context of global climate change. Eight years of continuous eddy covariance measurements (2003–2010) in a subtropical coniferous plantation were used to investigate the impacts of climatic factors and ecosystem responses on the inter-annual variability of ET. The mean and standard deviation of annual ET for 2003–2010 were 786.9 and 103.4 mm (with a coefficient of variation of 13.1%), respectively. The inter-annual variability of ET was largely created in three periods: March, May–June, and October, which are the transition periods between seasons. A set of look-up table approaches were used to separate the sources of inter-annual variability of ET. The annual ETs were calculated by assuming that (a) both the climate and ecosystem responses among years are variable (Vcli-eco), (b) the climate is variable but the ecosystem responses are constant (Vcli), and (c) the climate is constant but ecosystem responses are variable (Veco). The ETs that were calculated under the above assumptions suggested that the inter-annual variability of ET was dominated by ecosystem responses and that there was a negative interaction between the effects of climate and ecosystem responses. These results suggested that for long-term predictions of water and energy balance in global climate change projections, the ecosystem responses must be taken into account to better constrain the uncertainties associated with estimation.
Adjustment of the annual cycle to climatic change in a long-lived migratory bird specie  [cached]
A. P. M?LLER,E. FLENSTED-JENSEN,W. MARDAL
Current Zoology , 2009,
Abstract: Climate change has advanced the phenology of many organisms. Migratory animals face particular problems because climate change in the breeding and the wintering range may be asynchronous, preventing rapid response to changing conditions. Advancement in timing of spring migration may have carry-over effects to other parts of the annual cycle, simply because advancement of one event in the annual cycle also advances subsequent events, gradually causing a general shift in the timing of the entire annual cycle. Such a phenotypic shift could generate accumulating effects over the years for individuals, but also across generations. Here we test this novel hypothesis of phenotypic response to climate change by using long-term data on the Arctic tern Sterna paradisaea. Mean breeding date advanced by almost three weeks during the last 70 years. Annual arrival date at the breeding grounds during a period of 47 years was predicted by environmental conditions in the winter quarters in the Southern Ocean near the Antarctic and by mean breeding date the previous year. Annual mean breeding date was only marginally determined by timing of arrival the current year, but to a larger extent by arrival date and breeding date the previous year. Learning affected arrival date as shown by a positive correlation between arrival date in year (i + 1) relative to breeding date in year (i) and the selective advantage of early breeding in year (i). This provides a mechanism for changes in arrival date being adjusted to changing environmental conditions. This study suggests that adaptation to changing climatic conditions can be achieved through learning from year to year
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