7 research outputs found
Assessment of Nitrogen Use Efficiency in Algerian Saharan Maize Populations for Tolerance under Drought and No-Nitrogen Stresses
No full textIncreasing drought incidence and infertile soils require the improvement of maize for nitrogen use efficiency (NUE) under drought conditions. The objectives were to assess tolerance and genetic effects of Algerian populations under no-nitrogen and water stress. We evaluated a diallel among six Algerian maize populations under no-nitrogen vs. 120 kg/ha N fertilization and drought vs. control. Variability was significant among populations and their crosses for NUE under drought. Additive genetic effects could be capitalized using the populations BAH and MST, with high grain nitrogen utilization efficiency (NUtE). The most promising crosses were SHH × AOR with no-nitrogen supply under both water regimes for NUtE, AOR × IGS, under water stress for partial factor productivity (PFP), and well-watered conditions with nitrogen supply for protein content; AOR × IZM for agronomic nitrogen use efficiency (AE) under water stress; and AOR × BAH for grain nutrient utilization efficiency (NUtE) under well-watered conditions with nitrogen. These parents could be promising for developing drought-tolerant or/and low nitrogen hybrids to improve these traits. Maximum heterosis could be exploited using those populations and crosses. Reciprocal recurrent selection could be used to take advantage of additive and non-additive gene effects found based on estimations of genetic parameters
Combining Ability and Heterosis of Algerian Saharan Maize Populations (<i>Zea mays</i> L.) for Tolerance to No-Nitrogen Fertilization and Drought
No full textDrought and low nitrogen are major stresses for maize (Zea mays L.), and maize populations from the Sahara Desert are potential sources of stress tolerance. The objectives were to assess the tolerance and varietal and heterosis effects of Algerian populations under no-nitrogen fertilization and water stress. A diallel among six Algerian maize population was evaluated under drought (300 mm irrigation) vs. control (600 mm) and no-nitrogen fertilization vs. 120 kh ha−1 N fertilization. Genotypes showed significant differences and genetic effects for water- and nitrogen-stress tolerance. We propose a reciprocal recurrent selection to take advantage of additive and non-additive effects, using AOR and IGS, since they showed good performance in optimum and stress conditions, for improving yield heterosis for AOR × IGS. Negative effects are not expected on plant height, anthesis–silking interval or early vigor. These populations and BAH could be sources of inbred lines tolerant to drought and no-nitrogen fertilization. There was no relationship between origin and genetic group and stress tolerance per se or as parents of tolerant crosses. These populations and crosses could be used as base material among Algerian populations, for breeding programs focusing on tolerance to water or nitrogen stress
Combining ability and heterosis of maize (Zea mays L.) populations from the Algerian Sahara Desert under Mediterranean drought conditions
No full textDrought causes significant yield reduction in maize (Zea mays L.), and germplasm from the Saharan Desert offers potential sources of drought tolerance. Our objectives were to estimate heterosis and combining abilityamong Algerian maize populations under drought conditions and to identify populations and crosses as sources of drought tolerance for breeding programs in temperate environments. A diallel design without reciprocal ofsix populations was used. The populations per se, their respective crosses, and checks were evaluated in Algiers (Algeria) in 2016, 2017 and 2018. Algerian maize populations exhibited high phenotypic variability and genetic divergence under water stress. The populations IGS and AOR per se could provide favorable alleles for higher early vigor under drought, MST for reducing anthesis-silking interval (ASI), and both AOR and SHH for increasing yield under water stress. Among all crosses, IGS × MST was the most outstanding cross for reducing ASI, and IGS × SHH and BAH × SHH for increasing yield under water stress. Our results confirm the existence of heterotic relationships among Algerian maize populations from diverse origins under water stres
Genetic analyses of stay green for tolerance to water stress and nitrogen deficiency in Algerian Saharan maize populations
No full text18 páginas, 6 tablas, 1 figuraDelayed senescence could contribute to maintain yield under water stress and low nitrogen stress. Landraces from arid areas can provide favorable alleles for stay green under stress. The objectives of this study were to estimate varietal and heterosis effects of Algerian Saharan populations and their crosses for stay-green under water stress and no-nitrogen fertilization and to identify the most promising populations as sources of stay-green under stress. Six Algerian maize populations were evaluated in a diallel under water stress (300 mm irrigation) versus control (600 mm) and no-nitrogen fertilization versus 120 kg/ha N fertilization. Both varietal and specific heterosis were involved in delayed senescence under stress. Breeding programs could capitalize additive components by using the populations IZM or IGS with favorable varietal effects for delayed senescence under nitrogen stress, or dominance effects by using the population AOR with favorable heterotic effects for plant color under water and nitrogen stresses. Based on specific heterosis, under water stress conditions with no-nitrogen supply, the most promising cross was AOR × IZM for delayed senescence, while IZM × BAH (with no-nitrogen supply), and SHH × BAH (with nitrogen fertilizer), will allow a longer maintenance of the plant coloration. We suggest reciprocal recurrent selection with these populations for developing drought-tolerant and low nitrogen hybrids to improve stay-green.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was funded by the École Nationale Supérieure Agronomique; Spanish Ministerio de Innovación y Universidades (MCIU), the Agencia Estatal de Investigación (AEI) and the European Fund for Regional Development (FEDER), UE (project code PID2019-108127RB-I00) and by PRIMA, a program supported by the European Union under H2020 framework programme (Proj. 1586, Ref PCI2021-121912).Peer reviewe
Combining ability and heterosis of algerian saharan maize populations (Zea mays l.) for tolerance to no-nitrogen fertilization and drought
No full textDrought and low nitrogen are major stresses for maize (Zea mays L.), and maize populations from the Sahara Desert are potential sources of stress tolerance. The objectives were to assess the tolerance and varietal and heterosis effects of Algerian populations under no-nitrogen fertilization and water stress. A diallel among six Algerian maize population was evaluated under drought (300 mm irrigation) vs. control (600 mm) and no-nitrogen fertilization vs. 120 kh ha N fertilization. Genotypes showed significant differences and genetic effects for water-and nitrogen-stress tolerance. We propose a reciprocal recurrent selection to take advantage of additive and non-additive effects, using AOR and IGS, since they showed good performance in optimum and stress conditions, for improving yield heterosis for AOR × IGS. Negative effects are not expected on plant height, anthesis– silking interval or early vigor. These populations and BAH could be sources of inbred lines tolerant to drought and no-nitrogen fertilization. There was no relationship between origin and genetic group and stress tolerance per se or as parents of tolerant crosses. These populations and crosses could be used as base material among Algerian populations, for breeding programs focusing on tolerance to water or nitrogen stress.This research was funded by École Nationale Supérieure Agronomique d’Alger, and the
Spanish Ministerio de Innovación y Universidades (MCIU), the Agencia Estatal de Investigación (AEI)
and the European Fund for Regional Development (FEDER), UE (project code PID2019-108127RB-I00
Genetics of Germination and Seedling Traits under Drought Stress in a MAGIC Population of Maize
No full textDrought is one of the most detrimental abiotic stresses hampering seed germination, development, and productivity. Maize is more sensitive to drought than other cereals, especially at seedling stage. Our objective was to study genetic regulation of drought tolerance at germination and during seedling growth in maize. We evaluated 420 RIL with their parents from a multi-parent advanced generation inter-cross (MAGIC) population with PEG-induced drought at germination and seedling establishment. A genome-wide association study (GWAS) was carried out to identify genomic regions associated with drought tolerance. GWAS identified 28 and 16 SNPs significantly associated with germination and seedling traits under stress and well-watered conditions, respectively. Among the SNPs detected, two SNPs had significant associations with several traits with high positive correlations, suggesting a pleiotropic genetic control. Other SNPs were located in regions that harbored major QTLs in previous studies, and co-located with QTLs for cold tolerance previously published for this MAGIC population. The genomic regions comprised several candidate genes related to stresses and plant development. These included numerous drought-responsive genes and transcription factors implicated in germination, seedling traits, and drought tolerance. The current analyses provide information and tools for subsequent studies and breeding programs for improving drought tolerance.This research was funded by the École Nationale Supérieure Agronomique; PRIMA, a program supported by the European Union under H2020 framework programme; and Spanish Ministerio de Innovación y Universidades (MCIU), the Agencia Estatal de Investigación (AEI) and the European Fund for Regional Development (FEDER), UE (project code PID2019-108127RB-I00). Financial support has been also provided by PRIMA, a program supported by the European Union under the H2020 framework programme and by the project IN607A2021/07 from Xunta de Galicia.Peer reviewe
Control of Fusarium oxysporum f.sp. lycopersici by supernatants with siderophores of Acinetobacter sp.
No full textIlustracionesEl marchitamiento vascular del tomate causado por Fusarium oxysporum f. sp. lycopersici (Fol) es una de las enfermedades más limitantes del cultivo. El uso de fungicidas sistémicos y variedades resistentes a ciertas razas del patógeno no ha sido suficiente para su manejo. En este estudio se aislaron microrganismos productores de sideróforos con potencial biocontrolador sobre la cepa Fol59. Los aislamientos fueron obtenidos de muestras provenientes de la rizósfera y filósfera de árboles de cacao silvestre de cinco zonas de la Amazonía Colombiana. Los quince aislamientos seleccionados por su eficiencia en la síntesis de sideróforos, fueron clasificados dentro de los géneros Acinetobacter sp. (9), Bacillus sp. (2), Delftia sp. (1), Serratia sp. (1), Pseudomonas sp. (1) y Herbaspirillum sp. (1). La aplicación previa a la infección con Fol59 de los sobrenadantes con alto contenido de sideróforos (SodSid), de cinco de los aislamientos de Acinetobacter sp., logró disminuir el AUDPC de la severidad de la enfermedad hasta en un 45 %, siendo el aislamiento CBIO117 el que mayor actividad biocontroladora generó. Finalmente, se observó que los SodSid de Acinetobacter CBIO117 indujeron la expresión de los genes PR1 y ERF1 marcadores de las vías hormonales del Ácido Salicílico y Etileno en la planta respectivamente, pero no del gen (MYC2), factor de transcripción de los genes de defensa dependientes del Ácido Jasmónico. Sin embargo, en las plantas estimuladas con los SodSid CBIO117 e infectadas con Fol59 se indujo la expresión de manera diferencial del gen MYC2, destacando la activación de la defensa dependiente del ácido Jasmónico. Estos resultados demuestran el potencial biocontrolador que tienen los sobrenadantes con sideróforos secretados por aislamientos del género Acinetobacter sp. en la disminución del marchitamiento vascular del tomate, actuando como posibles elicitores de la respuesta de defensa de la planta. (texto tomado de la fuente)The vascular wilt disease of tomato caused by Fusarium oxysporum f. sp. lycopersici (Fol) is one of the most limiting diseases of this crop. The use of systemic fungicides and varieties resistant to certain races of the pathogen have not provided an adequate control. In this study, siderophore-producing microorganisms with biocontrol potential against Fol were isolated from rhizosphere and phyllosphere samples taken from wild cocoa trees in five different locations of the Colombian Amazon. The fifteen isolates selected for being representative of the sampling zones and showing greater production of siderophores were classified within the genera Acinetobacter sp. (9), Bacillus sp. (2), Delftia sp. (1), Serratia sp. (1), Pseudomonas sp. (1) y Herbaspirillum sp. (1). The application before infection with Fol59 of supernatants with a high content of siderophores (SodSid) from five Acinetobacter sp. isolates caused a reduction in the AUDPC of the disease severity of up to 45%, being CBIO117 the isolate which showed greater biocontrol activity. Finally, it was confirmed that SodSid Acinetobacter CBIO117 generated an induction in the expression of PR1 and ERF1 genes, markers of the Salicylic Acid and Ethylene hormonal pathways in the plant, respectively. In contrast the gene (MYC2), a transcription factor of the Jasmonic Acid-dependent defense genes was not expressed. However, in plants stimulated with SodSid CBIO117 and infected with Fol59, MYC2 gene expression was differentially induced, highlighting the activation of the Jasmonic acid-dependent defense that possibly led to counteracting the infection process of the pathogen and reducing the severity of the disease. Our results demonstrate the biotechnological potential of siderophore-producing isolates of the genus Acinetobacter sp. for the control of plant pathogens, eliciting the defensive response in the plant.MaestríaMagíster en Ciencias AgrariasÁrea Curricular en Producción Agraria Sostenibl
