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1.
Sci Total Environ ; 918: 170387, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38280604

RESUMO

Glyphosate hormesis, identified as a potential means to enhance crop yields, encounters practical constraints because it is typically assessed through foliar applications. The expression and extend of hormesis in this approach are influenced by unpredictable environmental conditions, highlighting the need to explore alternative glyphosate application methods, such as seed treatment. This study aimed to assess glyphosate hormesis on growth rates and biomass accumulation in seedlings soybean cultivars. Two dose-response experiments [doses from 0 to 2880 g acid equivalent (ae) ha-1], one via foliar and one via seed, were conducted on three soybean cultivars [one non-glyphosate-resistant (NGR) and two glyphosate-resistant (GR, one RR and one RR2)]. In a subsequent experiment, three safe glyphosate doses (0, 90 and 180 g ae ha-1) applied via seed were evaluated on four soybean cultivars (two RR and two RR2). For foliar applications, the range of glyphosate doses increasing growth rates and dry biomass by 12-28 % were 5.6-45 g ae ha-1 for the NGR cultivar, of 45-720 g ae ha-1 for RR and of 11.25-180 g ae ha-1 for RR2. In the seed treatment, biomass increases of 16-60 % occurred at 45-180 g ae ha-1 for the NGR and RR cultivars, and 90-360 g ae ha-1 for RR2. Glyphosate doses of 90 and 180 g ae ha-1, applied via seeds, provided greater growth and biomass accumulation for the RR and RR2 soybean cultivars. Both foliar and seed applications of glyphosate increased growth and biomass accumulation in soybean cultivars, with seed treatments showing greater and more consistent enhancements. These findings propose practical and viable alternative for harnessing glyphosate hormesis to facilitate the early development of soybeans and potentially enhance crop yield.


Assuntos
Glifosato , Herbicidas , Glycine max , Plântula , Glicina/toxicidade , Hormese , Herbicidas/toxicidade , Biomassa , Sementes
2.
Anim Biosci ; 37(1): 16-27, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37641833

RESUMO

OBJECTIVE: The objective of this study was to investigate the effect of heat stress on the growth traits and genetic parameters of Thai native chickens. METHODS: A total of 16,487 records for growth traits of Thai native chickens between 2017 and 2022 were used in this study. Data included the body weight at birth, body weight at 4, 8, and 12 weeks of age (BW0, BW4, BW8, BW12), average daily gain during 0 to 4, 4 to 8, and 8 to 12 weeks of age (ADG0-4, ADG4-8, ADG8-12), absolute growth rate at birth, at 4, 8, and 12 weeks of age (AGR0, AGR4, AGR8, AGR12). The repeatability test day model used the reaction-norm procedure to analyze the threshold point of heat stress, rate of decline of growth traits, and genetic parameters. RESULTS: At temperature and humidity index (THI) of 76, Thai native chickens began to lose their growth traits, which was the onset of heat stress in this study. The estimated heritability, genetic correlation between animal and heat stress effect, and correlations between the intercept and slope of the permanent environmental effects were 0.27, -0.85, and -0.83 for BW, 0.17, -0.81, and -0.95 for ADG, 0.25, -0.61, and -0.83 for AGR, respectively. Male chickens are more affected by heat stress than female chickens with a greater reduction of BW, ADG, and AGR, values equal to -9.30, -0.23, -15.21 (in males) and -6.04, -0.21, -10.10 (in females) gram per 1 level increase of THI from the THI of 76. CONCLUSION: The influence of thermal stress had a strong effect on the decline in growth traits and genetic parameters in Thai native chickens. This study indicated that genetic models used in conjunction with THI data are an effective method for the analysis and assessment of the effects of heat stress on the growth traits and genetics of native chickens.

3.
Genes (Basel) ; 14(4)2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37107660

RESUMO

Seed vigor is the key performance parameter of good quality seed. A panel was prepared by shortlisting genotypes from all the phenotypic groups representing seedling growth parameters from a total of 278 germplasm lines. A wide variation was observed for the traits in the population. The panel was classified into four genetic structure groups. Fixation indices indicated the existence of linkage disequilibrium in the population. A moderate to high level of diversity parameters was assessed using 143 SSR markers. Principal component, coordinate, neighbor-joining tree and cluster analyses showed subpopulations with a fair degree of correspondence with the growth parameters. Marker-trait association analysis detected eight novel QTLs, namely qAGR4.1, qAGR6.1, qAGR6.2 and qAGR8.1 for absolute growth rate (AGR); qRSG6.1, qRSG7.1 and qRSG8.1 for relative shoot growth (RSG); and qRGR11.1 for relative growth rate (RGR), as analyzed by GLM and MLM. The reported QTL for germination rate (GR), qGR4-1, was validated in this population. Additionally, QTLs present on chromosome 6 controlling RSG and AGR at 221 cM and RSG and AGR on chromosome 8 at 27 cM were detected as genetic hotspots for the parameters. The QTLs identified in the study will be useful for improvement of the seed vigor trait in rice.


Assuntos
Oryza , Plântula , Plântula/genética , Germinação/genética , Oryza/genética , Locos de Características Quantitativas/genética , Genômica
4.
J Appl Genet ; 64(2): 265-273, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36821070

RESUMO

There is a vast scope of area expansion of lentils after harvesting wet rice in South Asia. However, due to the photoperiod effect and terminal heat, the existing short-duration varieties failed to minimize yield loss under late-sown conditions. A mis-splicing causing A/G SNP present in the last nucleotide of exon 3 of early flowering 3 (ELF3) gene (elf3 allele) in a lentil line, L4710, is associated with the photoperiod insensitive flowering and the fast absolute growth rate (AGR). None of the Indian cultivars tested in this study, either early or late, possesses the non-functional elf3 allele. However, the A to G transition in ELF3-exon2 replaces glycine with aspartic acid at the 403rd amino acid in all the Indian varieties tested, compared to the reference sequence of Mediterranean accession, ILL5588. Therefore, targeting A/G SNP of exon 3, a PCR-based codominant marker is developed. The elf3 allele is correlated with the fast AGR and early flowering, but low yield and biomass, in an L4710 × LL56-derived RIL-population, compared to ELF3 carrying alleles when sown on 15th November. However, in a month of delayed sowing (20th December), the same elf3-RILs revealed a higher yield and biomass with slower AGR Moreover, three elf3-carrying lines, grown in delayed condition (20 December) for two consecutive years in three locations, outyielded three popular high-yielding cultivars that carry functional ELF3. Thus, elf3-carrying high-yielding lines could be the breeder's choice to expand and enhance lentil yield in short-season environments and in vast rice fallows of south Asia, where delayed rice harvest occurs frequently.


Assuntos
Fabaceae , Lens (Planta) , Alelos , Lens (Planta)/genética , Fotoperíodo , Fabaceae/genética , Ásia Meridional , Flores/genética
5.
Environ Pollut ; 316(Pt 1): 120523, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36326558

RESUMO

The generation of Fly Ash (FA) waste is continuously piling up with the increasing energy demand. Recent research is focused towards reutilizing this fly ash waste through bioremediation practices. But fly ash retards the growth of plants and holds back to support the bioremediation process due to a deficiency of essential main nutrients. The present research envisages overcoming this problem by providing a novel concept of inducing isolated microbes and treated wastewater which provides necessary nutrients and promotes better plant growth and metal extraction. A pot experimental study was executed with treatments T1 (FA amended soil), T2 (FA with isolated microbe), and T3 (FA with microbes and treated wastewater). As an outcome of the present research, T3 gained relatively higher morphological characteristics viz. Leaf area (29.8%), absolute growth rate (61.7%), plastochron index (18.6%), biomass yield (47.3%) and enhanced metal extraction for Fe (34.4%), Al (27.1%), Mn (72.0%), Zn (17.5%) in comparison to the control. Treatment T3 also gained higher Remediation Efficiency (RE) and Bio-Concentration Factor (BCF) values for Al, Fe, and Mn. The involvement of nutrients via treated wastewater energizes the process mechanism and increases the working zone for the microbes thereby, enhancing the bioremediation.


Assuntos
Jatropha , Metais Pesados , Poluentes do Solo , Solo , Cinza de Carvão/análise , Biodegradação Ambiental , Águas Residuárias , Poluentes do Solo/análise , Metais , Plantas , Metais Pesados/análise
6.
3 Biotech ; 12(10): 246, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36033911

RESUMO

Excess aluminum (Al) is a stressful condition that affects plant growth and yield quality. This study evaluates growth responses and changes in the contents of photosynthetic pigments and organic solute in maize (Zea mays L.) plants inoculated with Trichoderma asperelloides isolates (T01, T02, T74, T76, or T96) and treated with increasing doses of Al (0, 50, 100, 150, and 200 µM of Al). Uninoculated unstressed plants served as control. Absolute growth rate, root length, dry biomass (shoot, roots and total) and shoot:root ratio were significantly affected in Al-stressed maize plants inoculated with T. asperelloides. Also, chlorophylls (a, b and total) were significantly reduced, whereas carotenoids and anthocyanins increased in those plants. Except for carotenoids, all parameters increased in plants inoculated with T. asperelloides, especially T01 or T02 isolates. Anthocyanins increased by 50% in plants inoculated with T74 and treated with 100 or 150 µM Al as compared to control plants. Total soluble carbohydrates increased by 74% and 101% in plants inoculated with T74 and T76, respectively, and treated with 200 µM Al. Total free amino acids increased more than 50% in plants inoculated with T02 and treated with 150 and 200 µM Al. Free prolines increased by 90%, 145% and 165% in plants inoculated with T74 and treated 100, 150 and 200 µM Al, respectively, in comparison to the unstressed control plants. We concluded that T. asperelloides positively affected growth, photosynthetic pigments, and organic solutes of Al-stressed plants, especially those inoculated with T01, T02, or T74 isolates. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-022-03310-3.

7.
Anim Biosci ; 35(5): 648-658, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33561918

RESUMO

OBJECTIVE: The identification of nonlinear mixed models that describe the growth trajectory of New Zealand rabbits was performed based on weight records and carcass measures obtained using ultrasonography. METHODS: Phenotypic records of body weight (BW) and loin eye area (LEA) were collected from 66 animals raised in a didactic-productive module of cuniculture located in the southern Piauí state, Brazil. The following nonlinear models were tested considering fixed parameters: Brody, Gompertz, Logistic, Richards, Meloun 1, modified Michaelis-Menten, Santana, and von Bertalanffy. The coefficient of determination (R2), mean squared error, percentage of convergence of each model (%C), mean absolute deviation of residuals, Akaike information criterion (AIC), and Bayesian information criterion (BIC) were used to determine the best model. The model that best described the growth trajectory for each trait was also used under the context of mixed models, considering two parameters that admit biological interpretation (A and k) with random effects. RESULTS: The von Bertalanffy model was the best fitting model for BW according to the highest value of R2 (0.98) and lowest values of AIC (6,675.30) and BIC (6,691.90). For LEA, the Logistic model was the most appropriate due to the results of R2 (0.52), AIC (783.90), and BIC (798.40) obtained using this model. The absolute growth rates estimated using the von Bertalanffy and Logistic models for BW and LEA were 21.51g/d and 3.16 cm2, respectively. The relative growth rates at the inflection point were 0.028 for BW (von Bertalanffy) and 0.014 for LEA (Logistic). CONCLUSION: The von Bertalanffy and Logistic models with random effect at the asymptotic weight are recommended for analysis of ponderal and carcass growth trajectories in New Zealand rabbits. The inclusion of random effects in the asymptotic weight and maturity rate improves the quality of fit in comparison to fixed models.

8.
J Neurosurg ; 127(5): 971-980, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28084908

RESUMO

OBJECTIVE Advances in neuroimaging techniques have led to the increased detection of asymptomatic intracranial meningiomas (IMs). Despite several studies on the natural history of IMs, a comprehensive evaluation method for estimating the growth potential of these tumors, based on the relative weight of each risk factor, has not been developed. The aim of this study was to develop a weighted scoring system that estimates the risk of rapid tumor growth to aid treatment decision making. METHODS The authors performed a retrospective analysis of 232 patients with presumed IM who had been prospectively followed up in the absence of treatment from 1997 to 2013. Tumor volume was measured by imaging at each follow-up visit, and the growth rate was determined by regression analysis. Predictors of rapid tumor growth (defined as ≥ 2 cm3/year) were identified using a logistic regression model; each factor was awarded a score based on its own coefficient value. The probability (P) of rapid tumor growth was estimated using the following formula:[Formula: see text] RESULTS Fifty-nine tumors (25.4%) showed rapid growth. Tumor size (OR per cm3 1.07, p = 0.000), absence of calcification (OR 3.87, p = 0.004), peritumoral edema (OR 2.74, p = 0.025), and hyperintense or isointense signal on T2-weighted MRI (OR 3.76, p = 0.049) were predictors of tumor growth rate. In the Asan Intracranial Meningioma Scoring System (AIMSS), tumor size was categorized into 3 groups of < 2.5 cm, ≥ 2.5 to < 4.0 cm, and ≥ 4.0 cm in diameter and awarded a score of 0, 3, and 6, respectively; the parameters of calcification and peritumoral edema were categorized into 2 groups based on their presence or absence and given a score of 0 or 2 and 1 or 0, respectively; and the signal on T2-weighted MRI was categorized into 2 groups of hypointense and hyperintense/isointense and given a score of 0 or 2, respectively. The risk of rapid tumor growth was estimated to be < 10% when the total score was 0-2, 10%-50% when the total score was 3-6, and ≥ 50% when the total score was 7-11 (Hosmer-Lemeshow goodness-of-fit test, p = 0.9958). The area under the receiver operating characteristic curve was 0.86. CONCLUSIONS The authors suggest a weighted scoring system (AIMSS) that predicts the specific probability of rapid tumor growth for patients with untreated IM. This scoring system will aid treatment decision making in clinical settings by screening out patients at high risk for rapid tumor growth.


Assuntos
Neoplasias Meníngeas/patologia , Meningioma/patologia , Idoso , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Pessoa de Meia-Idade , Neuroimagem , Medição de Risco , Fatores de Risco , Tomografia Computadorizada por Raios X , Carga Tumoral
9.
Biosci. j. (Online) ; 32(5): 1221-1233, sept./oct 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-965694

RESUMO

Plant growth-promoting bacteria (PGPB) comprise of soil microorganisms that cause positive effects on plant growth. The hypothesis according to which the inoculation of lima bean with PGPB Bacillus stimulates vegetative growth, which may result in a higher plant productivity, was tested. Thus, this study aimed to evaluate the effects of inoculation of two varieties of lima bean (branca and boca de moça) with Bacillus sp., UFPEDA 472 strain, based on plant growth responses. The experiment was conducted in a greenhouse using a completely randomized design. Three treatments were applied separately to each lima bean variety: the first used inoculation with Bacillus, one was submitted to nitrogen supplementation, and one was the absolute control (non-inoculated plants). The following variables were evaluated: absolute and relative growth rate, root length, stem diameter, fresh and dry mass of shoots and roots, shoot:root ratio and total chlorophyll. The results showed that lima bean displayed better growth responses when inoculated with Bacillus sp. UFPEDA 472 in relation to the treatment with nitrogen and/or non-inoculated plants. When inoculated with PGPB Bacillus, the lima bean var. branca was superior to boca de moça in terms of root length and root dry mass. The lima bean var. boca de moça inoculated with Bacillus sp. UFPEDA 472 was superior to branca in terms of absolute growth rate, stem diameter, fresh and dry mass of shoot, shoot:root ratio and total chlorophyll. In general, the lima bean var. boca de moça inoculated with Bacillus shows a better growth performance. Our results suggest that growth responses of lima bean varieties branca and boca de moça are related with a positive interaction with the PGPB Bacillus.


Bactérias promotoras de crescimento em plantas (BPCP) compreendem microrganismos do solo que causam efeitos positivos no crescimento vegetal. A hipótese de que a inoculação de feijão-fava com BPCP Bacillus estimula o crescimento vegetativo, o qual pode resultar em uma maior produtividade vegetal, foi testado. Assim, este estudo objetivou avaliar o efeito da inoculação de duas variedades de feijão-fava (branca e boca de moça) com Bacillus sp., estirpe UFPEDA 472, baseado em respostas de crescimento vegetal. O experimento foi conduzido em casa de vegetação usando um delineamento completamente ao acaso. Três tratamentos foram aplicados separadamente à cada variedade de feijão-fava: o primeiro utilizou a inoculação com Bacillus sp. UFPEDA 472, um foi submetido à suplementação com nitrogênio e um foi o controle absoluto (plantas não inoculadas). As seguintes variáveis foram avaliadas: taxa de crescimento absoluto e relativo, comprimento das raízes, diâmetro do caule, massa fresca e seca da parte aérea e raízes, relação parte aérea:raiz e clorofila total. Os resultados mostram que o feijão-fava exibiu melhores respostas de crescimento quando inoculadas com Bacillus sp. UFPEDA 472 em relação ao tratamento com nitrogênio e/ou às plantas não inoculadas. Quando inoculado com Bacillus sp. UFPEDA 472, o feijão-fava var. branca foi superior à boca de moça em termos de comprimento e massa seca das raízes. O feijão-fava var. boca de moça inoculado com Bacillus sp. UFPEDA 472 foi superior à branca na taxa de crescimento absoluto, diâmetro do caule, massa fresca e seca da parte aérea, relação


Assuntos
Bacillus , Bactérias , Phaseolus/crescimento & desenvolvimento
10.
Ann Bot ; 115(1): 93-105, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25452250

RESUMO

BACKGROUND AND AIMS: Plant growth, the increase of organ dimensions over time, and development, the change in plant structure, are often studied as two separate processes. However, there is structural and functional evidence that these two processes are strongly related. The aim of this study was to investigate the co-ordination between growth and development using mango trees, which have well-defined developmental stages. METHODS: Developmental stages, determined in an expert way, and organ sizes, determined from objective measurements, were collected during the vegetative growth and flowering phases of two cultivars of mango, Mangifera indica. For a given cultivar and growth unit type (either vegetative or flowering), a multistage model based on absolute growth rate sequences deduced from the measurements was first built, and then growth stages deduced from the model were compared with developmental stages. KEY RESULTS: Strong matches were obtained between growth stages and developmental stages, leading to a consistent definition of integrative developmental growth stages. The growth stages highlighted growth asynchronisms between two topologically connected organs, namely the vegetative axis and its leaves. CONCLUSIONS: Integrative developmental growth stages emphasize that developmental stages are closely related to organ growth rates. The results are discussed in terms of the possible physiological processes underlying these stages, including plant hydraulics, biomechanics and carbohydrate partitioning.


Assuntos
Flores/crescimento & desenvolvimento , Mangifera/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Mangifera/genética , Modelos Biológicos
11.
Am J Bot ; 100(12): 2364-79, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24302692

RESUMO

PREMISE OF THE STUDY: Studies of domestication of cacti in the Tehuacán Valley have identified morphophysiological divergences between wild and cultivated populations. To determine whether such divergences are associated with differential survivorship in xeric and mesic environments characterizing wild and cultivated habitats, respectively, we hypothesized that seedlings from cultivated populations are less tolerant of xeric environments and that differences between wild and cultivated populations are greater in species with higher management intensity. METHODS: We compared size, survivorship, and absolute and relative growth rates (AGRs, RGRs) in shade and humidity gradients of seedlings from wild and cultivated populations of Stenocereus pruinosus, S. stellatus, Polaskia chichipe, and Escontria chiotilla. These species represent a range of management intensity, from highest to lowest, respectively. KEY RESULTS: Seedlings of cultivated populations were larger than those of wild populations in all species studied. The AGRs were significantly different in P. chichipe and E. chiotilla associated with management, whereas the RGRs and seedling survival were significantly different in S. pruinosus and P. chichipe throughout the shade gradient tested. We also found significant differences in seedling survival among humidity treatments in E. chiotilla and among shade treatments in P. chichipe. CONCLUSIONS: Artificial selection favoring larger fruits favors larger seeds and seedlings. Seedling survivorship and growth of managed plants are generally higher in mesic environments apparently because of natural selection associated with habitat conditions. Such differences may contribute to morphophysiological divergences between wild and cultivated populations. Interspecific differences might be associated with adaptations to the natural environments where each species occurs.


Assuntos
Adaptação Fisiológica/genética , Cruzamento , Cactaceae/genética , Ecossistema , Plântula/crescimento & desenvolvimento , Seleção Genética , Agricultura , Cactaceae/crescimento & desenvolvimento , Escuridão , Frutas/crescimento & desenvolvimento , Umidade , Sementes/crescimento & desenvolvimento , Especificidade da Espécie , Água
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