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Male Idesia polycarpa, which display distinct morphological and physiological traits, exhibit greater adaptability to stressful environments than females. However, the connection between this adaptability and rhizosphere processes remains unclear. Here, we investigate the differences in root bacterial community structures between male and female plants at different developmental stages, identifying bacterial strains associated with plant sex through functional predictions. This study aims to inform the optimal allocation of male and female plants during cultivation and provide a theoretical basis for sex identification and breeding. Samples from seven-year-old male and female plants were collected during the flowering (May) and fruit ripening (October) stages. Rhizosphere nutrient content and bacterial diversity were analyzed using Illumina high-throughput sequencing technology. The results demonstrate that total nitrogen (TN), total carbon (TC), and available potassium (AK) varied between sexes at different times. No significant differences between male and female plants were observed in the Shannon, Simpson, and Chao1 indexes during the flowering period. However, the Chao1 and Shannon indexes were significantly higher at fruit maturity in male rather than female plants. The predominant phyla of rhizosphere bacteria were Pseudomonadota, Acidobacteriota, and Actinomycetes. Interestingly, from flowering to fruit ripening, the dominant phyla in both male and female plants shifted from Actinomycetes to Pseudomonadota. A significant correlation was observed between pH and AK and rhizosphere bacteria (p < 0.05), with metabolism being the main functional difference. This study provides preliminary insights into the functional predictions and analyses of bacteria associated with Idesia polycarpa. The above findings lay the groundwork for further investigation into the sex-specific differences in microbial flora across different developmental stages, elucidating the mechanisms underlying flora changes and offering theoretical support for the high-quality management of Idesia polycarpa. [ABSTRACT FROM AUTHOR]

The escalation in the intensity, frequency, and duration of high-temperature (HT) stress is currently unparalleled, which aggravates the challenges for crop production. Yet, the stage-dependent responses of reproductive organs to HT stress at the morphological, physiological, and molecular levels remain inadequately explored in pivotal staple crops. This review synthesized current knowledge regarding the mechanisms by which HT stress induces abnormalities and aberrations in reproductive growth and development, as well as by which it alters the morphology and function of florets, flowering patterns, and the processes of pollination and fertilization in maize (Zea mays L.). We identified the stage-specific sensitivities to HT stress and accurately defined the sensitive period from a time scale of days to hours. The microspore tetrad phase of pollen development and anthesis (especially shortly after pollination) are most sensitive to HT stress, and even brief temperature spikes during these stages can lead to significant kernel loss. The impetuses behind the heat-induced impairments in seed set are closely related to carbon, reactive oxygen species, phytohormone signals, ion (e.g. Ca2+) homeostasis, plasma membrane structure and function, and others. Recent advances in understanding the genetic mechanisms underlying HT stress responses during maize sexual reproduction have been systematically summarized. [ABSTRACT FROM AUTHOR]

Drought stress is one of the most important limiting factors for plant growth and soil fertility, which causes crop yield reduction. In order to investigate the relative expression of genes related to drought stress tolerance, four genotypes (including two sensitive and two resistant genotypes to moisture stress) of bread wheat as factor A were subjected to a factorial experiment on basis randomized complete block design with three replications under normal and drought stress at the beginning of flowering stage as factor B in the research farm of Azerbaijan Shahid Madani University. The results of analysis of variance showed a significant difference at least at 1% probability level between drought stress levels according to most studied traits. Based on the results from the comparison of means of traits, the high tolerance of Eroum cultivar to drought stress was due to the higher increase in MDA and H2O2 and lower decrease in traits of chlorophyll a, total chlorophyll content, carotenoid content. In addition, the Mihan cultivar was more tolerant to drought stress because of the higher increase of proline, carotenoid, POX, and CAT, due to drought stress. The expression of genes in the examined samples was performed by semi-quantitative polymerase chain reaction in three replicates. Glutathione peroxidase gene (GAPDH) was used as housekeeping gene. Examining the relative expression level of antioxidant genes showed that the high tolerance of Mihan cultivar to drought stress can probably be attributed to the high activity of catalase and ascorbate peroxidase enzymes and the high tolerance of Arum cultivar to the higher activity of antioxidant enzymes proline synthetase, peroxidase and attributed to superoxide dismutase. Considering that the antioxidant genes catalase, ascorbate peroxidase, proline synthetase, peroxidase, and superoxide dismutase in tolerant cultivars showed a significant increase in expression under stress and normal conditions compared to sensitive cultivars under the same stress and normal conditions; so, this genes may induce tolerance to drought stress in plants under stress conditions. [ABSTRACT FROM AUTHOR]

The impact of water deficit severity and the specific growth stages at which water stress is applied have been found to have significant implications for both tomato yield and fruit quality. Recent findings have highlighted the influence of water deficits during the reproductive phase on tomato fruit quality. This study aimed to assess the effects of deficit irrigation on tomato fruit quality and overall plant productivity. Cherry tomatoes (Solanum lycopersicum var. cerasiforme) were grown in a greenhouse from August to November 2022. Three distinct watering regimes were implemented: Daily watering (T1), watering every 3 days (T2) and watering every 7 days (T3), starting from the flowering stage and continuing through subsequent plant development stages. The mean soil metric potentials (SMP) were -4.9, -29.7 and -52.8 kPa for T1, T2 and T3, respectively. Various traits of fruit size, fruit biomass, total soluble solids (TSS), water content, glucose content and lycopene content were measured. Additionally, the overall plant biomass and root-to-shoot ratio were evaluated. The results revealed that traits of the fruit size, such as diameter, length, volume and fresh weight, were most favorable when plants were subjected to the T2 watering regime, while higher and lower watering frequencies led to smaller fruit sizes. Interestingly, the TSS concentration had the most pronounced response to drought stress, indicating increased fruit sweetness. However, the fruit water content, glucose content and lycopene content remained unaffected by the different watering regimes. Furthermore, plants subjected to the T3 with the minimum SMP at -196.4 kPa exhibited enhanced development of the root system, prioritizing resource acquisition such as water and mineral nutrients over shoot components. In conclusion, this study provided valuable insights for agricultural practitioners, offering a range of alternatives that can inform optimal irrigation strategies that effectively enhance the quality of cherry tomato yields. [ABSTRACT FROM AUTHOR]

A comparative study was conducted on avian feeding guilds in winter and rainy crop seasons of guava at Punjab Agricultural University campus, Ludhiana, Punjab, during 2021-22. A total of 53 bird species belonging to 46 genera, 31 families and 13 orders were noted during the study period. The recorded bird species were classified into six feeding guilds. Except for insectivore, carnivore and omnivore birds, 13 species were recorded to play no beneficial role in the combined data of winter and rainy crop seasons. Relative abundance of insectivore bird species was found to be 40.34% at flowering stage, 25.44% at fruit set stage and 13.92% at fruit ripening stage in winter crop season; 35.43% at flowering stage, 26.35% at fruit set stage and 14.21% at fruit ripening stage in rainy crop season. Major feeding groups of omnivore and frugivore species were noted during the fruit ripening stage of both seasons. During rainy crop season, nine bird species were observed feeding on insects. A statistical analysis of avian feeding guilds using the T-test revealed a significant difference in flowering and fruit ripening stages of guava crop seasons in the winter and rainy seasons. [ABSTRACT FROM AUTHOR]

Flowering regulation is a reflection of plant self-adaptation to the environment and is the main determinant of plant yield. The quantitative trait loci (QTL) mapping of agronomic traits associated with the flowering stage of Agropyron Gaertn. was conducted using a cross-pollinated (CP) hybrid population with a total of 113 plant lines between A. mongolicum Keng Z2098 and A. cristatum (L.) Gaertn. Z1842 under four different environmental conditions and the genetic map constructed of 1,023 single-nucleotide polymorphism (SNP) markers. The results showed that 28 QTLs were detected on seven linkage groups. Each QTL explained 0.39–18.46% of the phenotypic variation, with a logarithm of odds (LOD) value ranging from 2.52 to 30.51. Specifically, QTLs were identified for various characteristics: one QTL identified for tiller number (TN), two for plant height (PH), three for days-to-flowering (DTF), five for flag leaf length (FLL), three for flag leaf width (FLW), three for spike length (SL), eight for spike width (SW), one for spikelet number per spike (SNS), and two for flower number per spike (FNS). One stable QTL controlling the SW was detected in two environments at the same loci and was located at 26 cM (Marker29867–Marker26864) on chromosome 5, showing a positive genetic effect. The two QTL enrichment regions suggested that the QTLs might contribute to trait correlation or pleiotropic genes. The identified QTLs potentially offer utility for marker-assisted breeding selection. [ABSTRACT FROM AUTHOR]

Nymphaea 'Eldorado', a valuable water lily, is a well-known fragrant plant in China. Studying the temporal and spatial characteristics of the floral components of this plant can provide a reference for the further development and utilization of water lily germplasm resources. In this study, headspace solid-phase microextraction (HS-SPME) combined with gas chromatography–mass spectrometry (GC-MS) was used to explore the types and relative contents of floral components at different flowering stages (S1: bud stage; S2: initial-flowering stage; S3: full-flowering stage; S4: end-flowering stage) and in different floral organs of N. 'Elidorado', combined with the observation of the microscopic structure of petals. A total of 60 volatile organic compounds (VOCs) were detected at different flowering stages, and there were significant differences in floral VOCs at different flowering stages and in different flower organs. The volatile compounds of N. 'Eldorado' can be divided into seven chemical classes,, namely, alkenes, alcohols, esters, aldehydes, ketones, alkanes, and others; the most common were alkenes and alkanes. A total of 39, 44, 47, and 42 volatile compounds were detected at S1, S2, S3, and S4. The VOCs present in high concentrations include benzaldehyde, benzyl alcohol, benzyl acetate, trans-α-bergamotene, α-curcumene, cis-α-farnesene, and so on. The types and total contents of volatiles at the full-flowering stage were higher than at other flowering stages. Comparing the VOCs in different parts of flower organs, it was found that the contents of alcohols, esters, and aldehydes were greatest in the petals, the alkenes in stamens were abundant with a relative content of up to 54.93%, and alkanes in the pistil were higher than in other parts. The types and total contents of volatiles in the stamens of N. 'Eldorado' were higher than those in other flower organs; they were the main part releasing fragrance. The observation of petal microstructure revealed that the size and quantity of the papillae on the epidermises of petals, the number of intracellular plastids, and the aggregates of floral components (osmophilic matrix granules) were significantly higher at the full-flowering stage than at the other flowering stages. This study suggested the main flowering stage and location at which the floral VOCs are released by N. 'Eldorado' and provided a reference for guiding the breeding of this water lily, exploring genetic patterns and developing related products. [ABSTRACT FROM AUTHOR]

Introduction: Lentil is a rich source of protein, fiber, minerals, antioxidants, folate, zinc, selenium, iron, and low amounts of fat and carbohydrates. Increasing water shortage and drought stress will be a major threat to global lentil production. The present study was conducted to determine the morphophysiological traits and grain of yield under normal and drought stress conditions, investigate tolerance indices and identify drought tolerance in some lentil genotypes. Materials and methods: In this experiment, twenty - four lentil genotypes were evaluated in the research farm of Shahrekord Faculty of Agriculture in two drought-stress environments and the normal conditions of the region in two separate randomized complete block designs with three replications experiments. In the 50% flowering stage, drought stress was done by completely stopping irrigation for the genotypes. Sampling was done at the end of the growing season. In this experiment, morphophysiological and yield traits were measured. Results and discussion: The results of composite data analysis showed that the effect of environment, genotype and the interaction effect of genotype × environment were significant on most traits. The share of these sources of variation in diversity of triats was different and environment placed on the most role in the diversity of seed yield (55.27%), genotype in the diversity of 100 seed weight (64.6%) and the number of single seed pods (53.9%). Seed yield in normal agricultural conditions has a positive correlation with most of the traits. In addition, under stress conditions, more traits had a significant correlation with grain yield. STI and GMP indices were highly correlated with yield in both environments and these indices can be used to select the superior genotype. Examining the main components of the indicators showed that the first component and two components justify 97.66% of the changes, the first component was introduced as a semi-tolerant component and the second component as a tolerant component. The results of the cluster analysis put the genotypes in three general groups. The results of cluster analysis based on STI and GMP indices put the genotypes in three separate groups. Conclusion: One of the main goals of production programs in arid and semi-arid regions is the screening of germplasm in different stages of plant growth. The results of the present research showed that drought stress in the reproductive stage reduces the morphophysiological traits and yield of lentil genotypes. Based on the results of seed yield, Kimia genotype with the lowest yield loss is known as the tolerant variety and C113 variety with the highest yield loss is known as the sensitive variety. Based on the results of seed yield, Kimia genotype with the lowest yield loss is known as the tolerant variety and C113 variety with the highest yield loss is known as the sensitive variety. [ABSTRACT FROM AUTHOR]

Alfalfa (Medicago sativa L.), a forage legume known for its moderate salt–alkali tolerance, offers notable economic and ecological benefits and aids in soil amelioration when cultivated in saline–alkaline soils. Nonetheless, the limited stress resistance of alfalfa could curtail its productivity. This study investigated the salt tolerance and growth-promoting characteristics (in vitro) of four strains of plant growth-promoting rhizobacteria (PGPR) that were pre-selected, as well as their effects on alfalfa at different growth stages (a pot experiment). The results showed that the selected strains belonged to the genera Priestia (HL3), Bacillus (HL6 and HG12), and Paenibacillus (HG24). All four strains exhibited the ability to solubilize phosphate and produce indole-3-acetic acid (IAA) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase. Among them, except for strain HG24, the other strains could tolerate 9% NaCl stress. Treatment with 100 mM NaCl consistently decreased the IAA production levels of the selected strains, but inconsistent changes (either enhanced or reduced) in terms of phosphate solubilization, ACC deaminase, and exopolysaccharides (EPS) production were observed among the strains. During the various growth stages of alfalfa, PGPR exhibited different growth-promoting effects: at the seedling stage, they enhanced salt tolerance through the induction of physiological changes; at the flowering stage, they promoted growth through nutrient acquisition. The current findings suggest that strains HL3, HL6, and HG12 are effective microbial inoculants for alleviating salt stress in alfalfa plants in arid and semi-arid regions. This study not only reveals the potential of indigenous salt-tolerant PGPR in enhancing the salt tolerance of alfalfa but also provides new insights into the mechanisms of action of PGPR. [ABSTRACT FROM AUTHOR]

Background: Salinity is a major limitation for rice farming due to climate change. Since salt stress adversely impact rice plants at germination, seedling, and reproductive stages resulting in poor crop establishment and reduced grain yield, enhancing salt tolerance at these vulnerable growth stages will enhance rice productivity in salinity prone areas. Methods and results: An introgression line (ILs) population from a cross between a high yielding cultivar 'Cheniere' and a salt tolerant donor 'TCCP' was evaluated to map quantitative trait loci (QTLs) for traits associated with salt tolerance at germination, seedling, and reproductive stages. Using a genotyping-by-sequencing based high density SNP linkage map, a total of 7, 16, and 30 QTLs were identified for five germination traits, seven seedling traits, and ten reproductive traits, respectively. There was overlapping of QTLs for some traits at different stages indicating the pleiotropic effects of these QTLs or clustering of linked genes. Candidate genes identified for salt tolerance were OsSDIR1 and SERF for the seedling stage, WRKY55 and OsUBC for the reproductive stage, and MYB family transcription factors for all three stages. Gene ontology analysis revealed significant GO terms related to nucleotide binding, protein binding, protein kinase activity, antiporter activity, active transmembrane transporter activity, calcium-binding protein, and F- box protein interaction domain containing protein. Conclusions: The colocalized QTLs for traits at different growth stages would be helpful to improve multiple traits simultaneously using marker-assisted selection. The salt tolerant ILs have the potential to be released as varieties or as pre-breeding lines for developing salt tolerant rice varieties. [ABSTRACT FROM AUTHOR]

High temperature around flowering has a serious impact on the growth and development of maize. However, few maize genes related to flowering under heat stress have been confirmed, and the regulatory mechanism is unclear. To reveal the molecular mechanism of heat tolerance in maize, two maize hybrids, ZD309 and XY335, with different heat resistance, were selected to perform transcriptome and metabolomics analysis at the flowering stage under heat stress. In ZD309, 314 up-regulated and 463 down-regulated differentially expressed genes (DEGs) were detected, while 168 up-regulated and 119 down-regulated DEGs were identified in XY335. By comparing the differential gene expression patterns of ZD309 and XY335, we found the "frontloaded" genes which were less up-regulated in heat-tolerant maize during high temperature stress. They included heat tolerance genes, which may react faster at the protein level to provide resilience to instantaneous heat stress. A total of 1062 metabolites were identified via metabolomics analysis. Lipids, saccharides, and flavonoids were found to be differentially expressed under heat stress, indicating these metabolites' response to high temperature. Our study will contribute to the identification of heat tolerance genes in maize, therefore contributing to the breeding of heat-tolerant maize varieties. [ABSTRACT FROM AUTHOR]

Background: Salinity is a major limitation for rice farming due to climate change. Since salt stress adversely impact rice plants at germination, seedling, and reproductive stages resulting in poor crop establishment and reduced grain yield, enhancing salt tolerance at these vulnerable growth stages will enhance rice productivity in salinity prone areas. Methods and results: An introgression line (ILs) population from a cross between a high yielding cultivar ‘Cheniere’ and a salt tolerant donor ‘TCCP’ was evaluated to map quantitative trait loci (QTLs) for traits associated with salt tolerance at germination, seedling, and reproductive stages. Using a genotyping-by-sequencing based high density SNP linkage map, a total of 7, 16, and 30 QTLs were identified for five germination traits, seven seedling traits, and ten reproductive traits, respectively. There was overlapping of QTLs for some traits at different stages indicating the pleiotropic effects of these QTLs or clustering of linked genes. Candidate genes identified for salt tolerance were OsSDIR1 and SERF for the seedling stage, WRKY55 and OsUBC for the reproductive stage, and MYB family transcription factors for all three stages. Gene ontology analysis revealed significant GO terms related to nucleotide binding, protein binding, protein kinase activity, antiporter activity, active transmembrane transporter activity, calcium-binding protein, and F- box protein interaction domain containing protein. Conclusions: The colocalized QTLs for traits at different growth stages would be helpful to improve multiple traits simultaneously using marker-assisted selection. The salt tolerant ILs have the potential to be released as varieties or as pre-breeding lines for developing salt tolerant rice varieties. [ABSTRACT FROM AUTHOR]

Context. As global temperatures increase, heat waves of >30°C for at least 3 days are projected to become more frequent during reproductive development of wheat, causing reductions in grain yield. Breeding for tolerance is difficult under field conditions owing to the unpredictable timing and intensity of natural heat events and the narrow developmental windows of sensitivity. Aims. We report on a series of experiments designed to explore genetic variability for floret sterility induced by natural heat waves in the field by targeting a sensitive development stage. Methods. Our method involved sowing late, and the use of auricle distance to identify main tillers exposed to heat events at a sensitive developmental stage (booting). Key results. Substantial genetic variation was found for tolerance of grain set to natural heat waves, with a broad-sense heritability estimate of 0.94 for heat-exposed stems compared with 0.72 for non-stressed controls. An auricle distance of 1-3 cm was established as a phenotypic marker for tagging stems at the sensitive stage of development, and the optimal number of spikes to assess was determined as 10-15 per plot. A validation study with durum lines previously classified as tolerant/intolerant under glasshouse conditions showed agreement in ranking of genotypes at the extremes of tolerance. Conclusions. We demonstrate that it is possible to screen wheat genotypes for stage-specific tolerance to natural heat waves in the field. Implications. The protocol described could provide a low-cost method for evaluating heat tolerance in wheat, with relevance to commercial field production conditions. The approach allows tolerance to be assessed at a single stage of reproductive development, which should allow greater heritability in field assessments. [ABSTRACT FROM AUTHOR]

Introduction: Legumes are the second most important food source in the world after cereals. Beans are very effective in stabilizing nitrogen and fertility of agricultural soil due to their coexistence with bacteria, and large amounts of nitrogen are added to the soil every year after harvesting this plant. Environmental factors, especially drought stress conditions, play a major role in the quantitative and qualitative characteristics of crops. Reduction of available water, especially at the beginning of the flowering stage and the occurrence of drought stress in legumes, while reducing the rate of vegetative growth and shortening the stage of reproductive growth has a negative effect on grain quality. Nutritional deficiencies in plants cause them to be sensitive to environmental stresses. Excessive use of chemical fertilizers in agriculture to provide the phosphate needed by plants has always caused adverse environmental effects and has led to a decline in the quality of agricultural products. However, the use of biofertilizers has many benefits over chemical fertilizers. Therefore, considering the importance of the above, the purpose of this study is to investigate the role of biofertilizer and phosphorus fertilizer on bean plant elements in drought stress conditions. Materials and Methods: An experimental split-split plot with three replications was performed to investigate the effect of bio-fertilizer and phosphate fertilizer application on nutrient uptake in roots, stems, and seeds of beans under drought stress in season 2016-2017 in Ilam city. Treatments included three levels of irrigation interruption (non-stress conditions, cut off in flowering stage, and cut off in pod formation stage) in the main plot and three levels of phosphate fertilizer (25, 50, and 100 kg. ha1) and application and non-application of biofertilizer. Drought stress treatment in this experiment was performed by stopping irrigation in two stages of full flowering and podding. All phosphorus fertilizer related to each treatment was applied to the ground at once during cultivation. After germination and establishment of the plants in the 2-4 leaf stage, the plants were thinned and one plant was kept in each pile. Weed control was done manually in two stages before flowering. Results and Discussion: The results showed that the highest nitrogen concentrations in roots, stems, and seeds under non-stress conditions (full irrigation) were 1.12, 1.77, and 3.19%, respectively. Also, the lowest nitrogen concentrations of roots, stems, and seeds in the cut-off flowering stage were 0.92, 1.46, and 2.63%, respectively. The mean comparison results showed that the highest grain nitrogen concentration in non-stress conditions (full irrigation) was 3.19%, which increased by 21.29% compared to the cut-off irrigation treatment at the flowering stage. The results showed that the highest concentration of root potassium in the conditions of irrigation interruption in the flowering stage and biofertilizer application was 2.63% and the lowest was obtained in the treatment without stress and non-application of biofertilizer (2%). The average comparison results showed that the highest concentration of potassium in the stem was obtained in the condition of cut off irrigation in the flowering stage at the rate of 4.35% and the lowest amount was obtained in the full irrigation at the rate of 3.60%. The results showed that in the treatment of biofertilizer application, the highest concentration of phosphorus in the grain was 0.265 percent, while the lowest in the treatment of nonapplication of biofertilizer was 0.226 percent. Conclusion:The application of phosphate fertilizer significantly increased the absorption of elements. The application of biofertilizer also significantly increased the concentration of nitrogen, potassium, and phosphorus in bean plants. In general, the results of this study showed that the use of biofertilizer and phosphate fertilizer could reduce the adverse effects of drought stress on bean plants and increase the absorption of elements in bean organs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Yield loss and toxin contamination caused by wheat Fusarium head blight (FHB) have always been a worldwide concern. Cultivating disease‐resistant varieties and fungicide application are effective measures to control FHB. The comprehensive control technology system for FHB and toxin contamination of wheat in Anhui Province needs further improvement. This study compared the control efficacy of different wheat varieties, fungicides and application times on wheat FHB and deoxynivalenol (DON) contamination, and the dynamic change of DON accumulation after application. RESULTS: Among the 93 main wheat varieties in Anhui Province, the disease‐resistant and low‐toxic wheat variety "Ningmai 26" was more suitable for planting in the central part of Anhui Province. At the same time, "Yangmai 22" was used for subsequent experiments. The field efficacy trials of different fungicides showed that 30% prothioconazole oil dispersion (OD) had the highest control efficacy on FHB and DON contamination, reaching 94.33 and 77.49%, respectively. The study on the optimum application time of prothioconazole showed that the 0–20% flowering stage was the key point of DON control. The survey of the dynamic changes of DON accumulation showed that prothioconazole could significantly reduce the level of DON accumulation while inhibiting the accumulation rate of DON. At the same time, the control fungicide carbendazim increased the level of DON contamination. CONCLUSION: This study will provide excellent germplasm resources for cultivating disease‐resistant and low‐toxic wheat varieties, and provide a theoretical reference for establishing a collaborative prevention and control system of disease control and toxin reduction. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

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The purpose of this study was to investigate the effects of nitrogen (N) application on the grain yield and antioxidant response in fragrant rice under high soil temperature during the flowering stage. A pot experiment was conducted with two conventional fragrant rice varieties, i.e., super rice variety (Yuxiangyouzhan) and non-super rice variety (Xiangyaxiangzhan) grown under two nitrogen application levels (ZN, 0 g N per 12 kg soil and AN, 1.75 g N per 12 kg soil) as well as two temperature levels (Ambient soil temperature, AT and high soil temperature, HT). The grain yield and antioxidant defense of super and non-super fragrant rice were evaluated. The results showed that significant differences in grain yield and antioxidant defense parameters with regard to the variety, temperature treatment, nitrogen treatment, and their interactions were detected. Compared with ZN, the AN treatment significantly increased the grain yield of Yuxiangyouzhan and Xiangyaxiangzhan by 55.06% and 13.32%, respectively, under AT conditions and by 32.62% and 29.19%, respectively, under HT condition. Besides, the antioxidant parameters varied by variety and temperature treatment at AN treatment. Nitrogen application had a significant effect on Superoxide dismutase (SOD) activity and Catalase (CAT) activity in the leaves. The results of this study confirmed that the N application could regulate grain yield and antioxidant capacity of fragrant rice at flowering stage under HT condition. [ABSTRACT FROM AUTHOR]

Sesame (Sesamum indicum L.) is a tropical oilseed crop that is also cultivated in arid and semi-arid environments, where drought occurs frequently. The objective of this study was to assess the performance of some sesame mutants, developed by our team through EMS-mutagenesis in 2020, under well-watered conditions and restricted irrigation by analyzing certain morphological, physiological, and agronomic attributes. The experiment was conducted in pots under field conditions according to a completely randomized design with three replications. The stress was simulated by suspending and reducing irrigation to 50% of the control, from the beginning of flowering until the appearance of the first capsule. The results showed variation attributable to genotypes, water regimes and their interaction was significant for all parameters studied, except the number of seeds per capsule. The mutants "ML2-5", "ML2-72" and "ML2-37" were found to be the most tolerant to drought, exhibiting lowest stress sensitivity index and highest seed yield were associated with higher proline content in the leaves, more developed root system, higher chlorophyll content, and higher stomatal conductance than the rest of the mutants studied. This is the first report of sesame mutant lines with such high tolerance to drought during flowering. They could be used for developing high-performing cultivars with tolerance to drought during the flowering stage. The number of capsules per plant and stomatal conductance can be considered selection criteria to improve water-stress tolerance in sesame. [ABSTRACT FROM AUTHOR]

Drought is a major crop production constraint worldwide. Some legume crops are known for their ability to resist water deficit stress. This study evaluated the responses of bambara groundnut (Vigna subterranea (L.) Verdc) and groundnut (Arachis hypogaea (L.) to soil water deficit stress. The experiment was set as a split-plot randomized complete block design. Three bambara groundnut landraces: viz DodR, NALBAM 4 and S19-3, and one groundnut variety, MNANJE, were assigned to subplots with three water regimes assigned to main plots (regime one: irrigated throughout the growing period, regime two: water deficit stress was imposed at the start of flowering to the end of first flush flowering, regime three: water was withheld during the pod development). Water deficit stress increased proline content by 123% in stressed plots. The highest (174%) and lowest (89%) proline increases were evident in the genotypes MNANJE and NALBAM 4, respectively. Water deficit decreased stomatal conductance, transpiration rate and photosynthetic rate, with MNANJE and S19-3 showing the smallest percentage decrease in most of the traits. This suggests that the two genotypes are drought resistant. The variations observed among landraces could be exploited to breed resilient varieties for cultivation in drought-prone areas, ultimately improving food security. [ABSTRACT FROM AUTHOR]

Populations of the same plant species living in different locations but flowering at different times may vary in pollinator availability and floral traits. However, the spatial and temporal links between floral traits and pollination are rarely included in single studies. In this study, three populations of an alpine lousewort, Pedicularis rhinanthoides Schrenk subsp. tibetica (Bonati) Tsoong, were surveyed to detect the variations in floral traits and pollinator activity. We hypothesized that floral divergence was spatio-temporally correlated with pollen limitation (PL) in relation to pollinators. Sampled plants from each population were divided into three groups, according to flowering stage: early, peak, and late. Pollen-supplementation experiments and investigations into pollinators, reproductive success, and floral traits were conducted on the plants from the different flowering stages and across the populations. Our results showed that the extent of PL varies across populations and among flowering stages. Populations in which more pollinators were recorded displayed a lower extent of PL. Furthermore, the temporal differences in PL showed a similar pattern for the three populations; the plants from the peak flowering stage suffered slighter PL than those from the other two stages. Nevertheless, some of the floral traits displayed similar spatial and temporal patterns to the PL, while the others only varied among the populations spatially. The results indicated that the performance of floral traits in a particular spatial–temporal situation shows they are well adapted to the corresponding pollination environment, which might help plants to optimize their reproductive fitness under different abiotic factors. [ABSTRACT FROM AUTHOR]

Current agricultural methodologies are vulnerable to erratic climate and are dependent on cost-intensive fertilization to ensure high yields. Sustainable practices should be pursued to ensure food security. Phaseolus vulgaris L. is one of the most produced legumes worldwide and may be an alternative to reduce the environmental impact of meat production as a reliable source of high-quality protein. Plant growth-promoting rhizobacteria (PGPR) are emerging as a sustainable option to increase agricultural production. To understand the dynamics between plants and microorganisms, the culturable microbiota of bean roots was isolated and identified at distinct stages of plant development (early and late vegetative growth, flowering, and pod) and root compartments (rhizoplane, endosphere, and nodules). Diversity and abundance of bacteria associated with root compartments differed throughout the plant life cycle. Bacterial plant growth promotion (PGP) and protection abilities (indole-3-acetic acid production, siderophore synthesis, and antifungal activity) were assessed and associated with plant phenology, demonstrating that among the bacteria associated with plant roots, several strains had an active role in the response to plant biological needs at each stage. Several strains stood out for their ability to display one or more PGP traits, being excellent candidates for efficient stage-specific biostimulants for application in precision agriculture. [ABSTRACT FROM AUTHOR]

Aphid is one of the main insect pests of wheat in the flowering stage, so timely and effective control of wheat aphids plays an important role in ensuring wheat yield. The crop protection Unmanned Aerial Vehicle (UAV) is widely used in the control of wheat pests and diseases nowadays. In order to screen out the suitable operation parameters of the crop protection UAV to control the wheat aphids, this study conducted wheat aphid distribution investigation tests and droplet distribution tests. With the P20 electric four-rotor crop protection UAV (Guangzhou Jifei Technology Co., Ltd., Guangzhou, China) as the test equipment, four levels of flight speed (FS: 3, 4, 5, 6 m/s) and three levels of flight height (FH: 1.5, 2, 2.5 m) were combined as operation parameters, tests were carried out to compare the density and uniformity of droplet coverage, and the wheat aphid control tests were carried out by using the optimized operation parameters. The results of the wheat aphid distribution investigation test showed that aphids mainly distributed in the lower layer of the wheat plant canopy, accounting for more than 90.61%. The results of the droplet distribution test showed that with the increase in FS and FH, the coverage density and the droplet distribution uniformity in the upper and lower layers of wheat showed a downward trend under the condition of considering the boundary overlap of spraying width (SW) in multi-routes. Through the comparison of operation efficiency and droplet distribution quality, two combinations of parameters A1 (FS: 3 m/s, FH: 1.5 m) and B1 (FS: 4 m/s, FH: 1.5 m) were selected for the aphid control effect test. The results of the control test showed that the average control effect of A1 (92.05%) on aphids was 10.3% higher than that of B1 (81.75%) 7 days after pesticide application, which indicated that improving the droplet distribution uniformity in the lower layer of wheat could significantly improve the control effect of aphids. This study result could provide reference for the same type of crop protection UAV to control the same type of wheat diseases and insect pests in the same growing stage. [ABSTRACT FROM AUTHOR]

Rice is highly vulnerable to salt stress at both seedling and flowering stage. While research efforts largely focused on seedling stage salinity tolerance, flowering stage salt tolerance studies are limited. Development of rice cultivars with salt tolerance at both stages will enhance rice productivity in salt affected farmlands. In the present study, two introgression line (IL) populations of a salt-tolerant landrace 'Nona Bokra (N)' were developed in the genetic backgrounds of two U.S. cultivars 'Cheniere (C)' and 'Jupiter (J)' and were evaluated for elucidation of the genetic basis of agronomically important traits at flowering stage and development of salt tolerant pre-breeding lines. Evaluation of both sets of ILs (JN-ILs and CN-ILs) under saline (EC = 8 dSm−1) environment led to identification of a total of 33 QTLs for seven different yield and yield component traits impacted by salt stress. Majority of large-effect QTLs for traits such as panicle length (qPL1.1JN), spikelet sterility (qSS1.1JN), thousand-grain weight (qTGW1.1JN), days to flowering (qDFF1.1CN), and plant height (qPH1.1CN) were located on chromosome 1. Some candidate genes present within the major effect QTL regions include potassium channel OsKAT1, NAC domain-containing protein, potassium transporters, and photosensitive leaf rolling 1. Comparison of the results with earlier reports on seedling stage suggested a different set of genes controlling salt tolerance at both stages. In addition, pre-breeding lines with improved flowering stage salinity tolerance were identified. These pre-breeding rice lines will accelerate fine mapping, map-based cloning, and pyramiding of desirable alleles for both flowering and seedling stage salt tolerance through marker assisted selection. [ABSTRACT FROM AUTHOR]

Plants developing into the flowering stage undergo major physiological changes. Because flowers are reproductive tissues and resource sinks, strategies to defend them may differ from those for leaves. Thus, this study investigates the defences of flowering plants by assessing processes that sustain resistance (constitutive and induced) and tolerance to attack. We exposed the annual plant Brassica nigra to three distinct floral attackers (caterpillar, aphid and bacterial pathogen) and measured whole‐plant responses at 4, 8 and 12 days after the attack. We simultaneously analysed profiles of primary and secondary metabolites in leaves and inflorescences and measured dry biomass of roots, leaves and inflorescences as proxies of resource allocation and regrowth. Regardless of treatments, inflorescences contained 1.2 to 4 times higher concentrations of primary metabolites than leaves, and up to 7 times higher concentrations of glucosinolates, which highlights the plant's high investment of resources into inflorescences. No induction of glucosinolates was detected in inflorescences, but the attack transiently affected the total concentration of soluble sugars in both leaves and inflorescences. We conclude that B. nigra evolved high constitutive rather than inducible resistance to protect their flowers; plants additionally compensated for damage by attackers via the regrowth of reproductive parts. This strategy may be typical of annual plants. Results show that flowering Brassica nigra protect their inflorescences with constitutive resistance rather than with inducible resistance, and compensate for floral dammage with early changes in primary metabolism and regrowth. Metabolic profiles reflected high resource investment into reproduction. [ABSTRACT FROM AUTHOR]

Global climate change has increased the frequency of extreme climate events, and their effects on the nutritional quality, especially on amino acids in rice, have not been quantified. The data from a 3-year low temperature stress (LTS) experiment including two rice varieties (Huaidao 5 and Nanjing 46), seven minimum/maximum temperature levels (one optimal 21/27°C and six LTS levels from 17/23 to 6/12°C), and three LTS durations (3, 6, and 9 days) after flowering, revealed significant interactive effects of LTS at different stages, durations, and temperature levels on the content and accumulation of amino acids. LTS increased rice total amino acid content, while decreasing its accumulation, with higher sensitivities to LTS at the flowering stage than at the grain filling stage. In most treatments, the lysine (the first limiting amino acid) and phenylalanine content were increased under LTS at early and peak flowering stages but decreased at the grain filling stage in both varieties, and only leucine content was increased at all three stages after flowering, while the content of other essential amino acids differed among the two varieties. With an increase of 1°C·d per day in the accumulated cold degree days, the relative content of the essential amino acids was increased by 0.01–0.41%, depending on the rice variety and growth stage. Our results suggest that LTS can improve nutritional quality of amino acids of rice grains in terms of amino acids content, especially at flowering stage. These results provide critical insights for assessing the potential impact of extreme climates on the nutrient quality of rice under future climate change. [ABSTRACT FROM AUTHOR]

Salvia eremophila Boiss. is an endemic plant from Iran. Plant metabolites are directly affected by some environmental factors. In following, secondary metabolites and chemical compounds might be varied that this variation can lead to changes the pharmacological efficacies. To investigate chemical variation of the species in different natural habitats, the essential oils were extracted by hydro-distillation method using Clevenger apparatus. Comparative outcomes revealed considerable variations in the obtained oils and constitutions. The essential oil yield varied between 0.69-0.81% during full flowering stages. The essential oil analyses identified 14 compounds (86.7-94.1% of the total oil) among which α-pinene (48.7-52.7%) was the highest component in all studied populations. The other main compositions were borneol (11.5-14.7%), isobornyl acetate (9.1-10.8%), and trans-Caryophyllene (6.9-8.2%). Based on the present research it could be found that chemical variation of S. eremophila in the studied areas is considerable. Ghavam Abad was the best one in quality and quantity of the chemical compounds. [ABSTRACT FROM AUTHOR]

Climate change has resulted in a continuous increase in the frequency and intensity of chilling events in cold regions. In Northeast China, chilling at the booting and flowering stages negatively affects japonica rice grain yield. In this field experiment study, we conducted a 2‐year temperature‐controlled experiment to investigate the effects of chilling temperature and duration applied at the booting and flowering stages on japonica rice. The results showed that chilling at the two study stages delayed the rice phenology and decreased the grain yield. In particular, japonica rice was more sensitive to chilling at the booting stage than at the flowering stage. The rice grain yield was reduced by more as the chilling temperature decreased and the chilling duration increased. As for the yield components, the spikelet fertility and grain number per spike were more sensitive to chilling at the booting stage than at the flowering stage. Variations in the grain yield per plant were primarily contributed by the differences in spikelet fertility and grain number per spike, especially the spikelet fertility. In addition, cooling degree days showed statistically significant negative correlations with grain yield per plant, grain number per spike and spikelet fertility. For every 10°C·day increase in CDD at the booting (flowering) stage, the grain yield per plant, spikelet fertility and grain number per spike decreased by 7.1%, 6.2% and 3.4% (3.9%, 5.0% and 1.2%) respectively. As the spikelet fertility and grain number per spike decreased, the sink capacity decreased as well with the increasing of allocated assimilation to the stem and leaf while decreasing the assimilation allocated to the panicle. Increasing cooling degree days at the booting and flowering stages increased the allocations of assimilation to the stem and leaf. As a result, less assimilation was allocated to the panicle. This study suggests that breeding cultivars to improve the spikelet fertility and grain number per spike could help to minimize the potential rice grain yield loss due to the increase in chilling events occurring at the booting and flowering stages. [ABSTRACT FROM AUTHOR]

Drought is one of the most critical environmental factors constraining maize production. When it occurs at the flowering stage, serious yield losses are caused, and often, the damage is irretrievable. In this study, anthesis to silk interval (ASI), plant height (PH), and ear biomass at the silking date (EBM) of 279 inbred lines were studied under both water-stress (WS) and well-water (WW) field conditions, for three consecutive years. Averagely, ASI was extended by 25.96%, EBM was decreased by 17.54%, and the PH was reduced by 12.47% under drought stress. Genome-wide association studies were carried out using phenotypic values under WS, WW, and drought-tolerance index (WS-WW or WS/WW) and applying a mixed linear model that controls both population structure and relative kinship. In total, 71, 159, and 21 SNPs, located in 32, 59, and 12 genes, were significantly (P < 10−5) associated with ASI, EBM, and PH, respectively. Only a few overlapped candidate genes were found to be associated with the same drought-related traits under different environments, for example, ARABIDILLO 1, glycoprotein, Tic22-like, and zinc-finger family protein for ASI; 26S proteasome non-ATPase and pyridoxal phosphate transferase for EBM; 11-ß-hydroxysteroid dehydrogenase, uncharacterised, Leu-rich repeat protein kinase, and SF16 protein for PH. Furthermore, most candidate genes were revealed to be drought-responsive in an association panel. Meanwhile, the favourable alleles/key variations were identified with a haplotype analysis. These candidate genes and their key variations provide insight into the genetic basis of drought tolerance, especially for the female inflorescence, and will facilitate drought-tolerant maize breeding. [ABSTRACT FROM AUTHOR]

Plants phenology is extremely important tool for crop management, crop manipulation, and marketing. The objective of this research was to investigate the phenology and fruit quality of the several Annonaceae species under subtropical conditions of Homestead, Florida, USA. The study was carried out in an experimental sugar apple (Annona squamosa L.), orchard with cultivars: 'LeahReese', 'Lessard Thai' and 'Red' and the atemoya 'Gefner' (A. cherimola x A. squamosa L). Ten uniformly vigorous and healthy plants of each cultivar were selected. The fruit harvest period was similar for all the cultivars, except for sugar-apple 'LeahReese', which had the shortest harvest period of only 41 days. Multivariate analysis showed that 'Lessard Thai' and 'Red' sugar apple cultivars had smaller sizes and lower chemical quality. Cultivar "LeahResse" had the highest fruits, in addition, a strong correlation with the atemoya hybrid "Gefner". The sugar apples 'Lessard Thai' and 'Red' had similar phenology and had a 166-day pruning to harvest cycle. In contrast, 'LeahReese' sugar apple and 'Gefner' atemoya had significantly longer cycles of 182 and 196 days, respectively. The sugar apple 'LeahReese' had the best physical characteristics of the cultivars investigated, while the atemoya 'Gefner' had the best physiochemical characteristics and the longest shelf life. [ABSTRACT FROM AUTHOR]

Background and Aims Cold stress in rice (Oryza sativa) plants at the reproductive stage prevents normal anther development and causes pollen sterility. Tapetum hypertrophy in anthers has been associated with pollen sterility in response to cold at the booting stage. Here, we re-examined whether the relationships between anther abnormality and pollen sterility caused by cold stress at the booting stage in rice can be explained by a monovalent factor such as tapetum hypertrophy. Methods After exposing plants to a 4-d cold treatment at the booting stage, we collected and processed anthers for transverse sectioning immediately and at the flowering stage. We anatomically evaluated the effect of cold treatment on anther internal morphologies, pollen fertilities and pollen numbers in the 13 cultivars with various cold sensitivities. Key Results We observed four types of morphological anther abnormalities at each stage. Pollen sterility was positively correlated with the frequency of undeveloped locules, but not with tapetum hypertrophy as commonly believed. In cold-sensitive cultivars grown at low temperatures, pollen sterility was more frequent than anther morphological abnormalities, and some lines showed remarkably high pollen sterility without any anther morphological alterations. Most morphological anomalies occurred only in specific areas within large and small locules. Anther length tended to shorten in response to cold treatment and was positively correlated with pollen number. One cultivar showed a considerably reduced pollen number, but fertile pollen grains under cold stress. We propose three possible relationships to explain anther structure and pollen sterility and reduction due to cold stress. Conclusions The pollen sterility caused by cold stress at the booting stage was correlated with the frequency of entire locule-related abnormalities, which might represent a phenotypic consequence, but not a direct cause of pollen abortion. Multivalent factors might underlie the complicated relationships between anther abnormality and pollen sterility in rice. [ABSTRACT FROM AUTHOR]

Preliminary studies observed a lower growth activity during the vegetative stage with higher growth attributes at the pod-filling stage among the high nitrogen (N) utilisation efficiency (NUtE) oilseed rape (Brassica napus L.) genotypes, compared with the low NUtE genotypes. Therefore, we hypothesised that there would exist a critical growth stage when distinctive phenotypic traits are exhibited to regulate yield formation and NUE. A field experiment and a hydroponic culture were conducted to characterise the differences in shoot and root physiological indicators of the high and low NUtE oilseed rape genotypes at seedling, bud, bolting, flowering and pod-filling stages. We found that flowering was the critical period when the reverse growth habit occurred between high and low NUtE genotypes. The high NUtE genotypes displayed larger values of root traits, stronger N uptake kinetics parameters, higher activity of leaf glutamine synthetase (GS) and glutamate synthetase (GOGAT), larger SPAD values and net photosynthetic rate, ultimately leading to higher seed yield and NUE. Our results indicate that flowering is the critical growth stage to distinguish the high from low NUtE oilseed rape genotypes, and plant breeders may focus on selecting root and shoot phenotypic traits from flowering stage onwards to achieve both high yields and NUE for oilseed rape genotypes. [ABSTRACT FROM AUTHOR]

Copyright of Lucrari Stiintifice, Universitatea de Stiinte Agricole Si Medicina Veterinara Ion Ionescu de la Brad Iasi, Seria Horticultura is the property of University of Agricultural Sciences and Veterinary Medicine (Editura Ion Ionescu de la Brad) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rice is highly sensitive to salt stress at flowering stage. With the objective of detection of quantitative trait loci (QTLs) in multi-environment for this stage, 180 backcross-derived lines (BC3F5) from salt tolerant donor Pokkali (AC41585) and recurrent parent IR 64 were subjected to evaluation in saline (EC = 8 dSm−1) and non-saline environments in wet season of 2014 and 2015 employing a novel phenotyping protocol. Nine multi-environmental consistent QTLs for spikelet degeneration, K+ concentration in flag leaf, stress susceptibility index for grain (SSI-Grain) and spikelet sterility (SSI-STE) on chromosomes1, 2, 3, 4 and 11 with 17–42% phenotypic variances were detected. Among several digenic epistatic interactions, one was associated with the main effect QTL (qSSI-STE-11-1) over the years. Similarly genotype × environment interaction associated with two additive QTLs, qDEG-S-2-2 and qSSI-STE-2-1 had positive effect on the resultant phenotype. Functional genes encoding calmodulin-binding protein and potassium transporter were predicted inside the consistent QTLs. Detected stable QTLs, associated markers, predicted genes and derived introgression lines with these QTLs could be utilized in future breeding programme. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the changes in the chemical composition of essential oils (EO) and the correlation between some secondary metabolites and antioxidant activity of different plant parts of Perovskia abrotanoides Kar. at the vegetative and flowering stages in Vamnan (Iran) in 2018. The EO of this plant was analyzed using the GC-Mass Spectrometry method. As the findings showed, P. abrotanoides leaf, during the flowering stage, had a greater amount of phenolic compounds, flavonoids, and anthocyanins than other parts and even the vegetative stage. At the flowering stage, the maximum antioxidant activity was obtained in the leaf (69.10%), based on the DPPH method. During the vegetative stage, the root was also in the next rank (62.10%). In this research, aerial parts of P. abrotanoides were different in terms of EO composition percentage and retention time. Likewise, 21 and 26 constitutes were identified during the vegetative and flowering stages, respectively. The major constitute was Carotol (31.105%) at the flowering stage, where IR-alpha-pinene (0.268%) had the lowest value. Overall, the results showed that P. abrotanoides can be introduced as an important source of natural antioxidant for pharmaceutical and natural food supplements due to its acceptable amount of bioactive compounds such as phenolic, flavonoids, anthocyanins, and EO. [ABSTRACT FROM AUTHOR]

Based on the daily average temperature from March 19 to April 2, 2021 at three surface meteorological stations in western Guizhou and the daily average temperature, maximum temperature and minimum temperature from March 19 to April 2, 2021 at 12 main automatic meteorological stations of red cartridge kiwifruit base, the effects of low temperature and high temperature on flowering and pollination of red cartridge kiwifruit in early spring of 2021 were analyzed. The results showed that slight cold spell in later spring in western Guizhou occurred from March 21 to 23. The lower limit of the daily average temperature required for flowering period (12 °C or below) appeared in each base of red cartridge kiwifruit during March 21 -23, which affected the red cartridge kiwifruit trees in Faer, Houchang, Miluo, Shunchang, Panlong and Jichang bases flowering and pollinating before March 20. From March 29 to April 2, the daily maximum temperature of Faer and other eleven bases was 30 °C or above, which caused the wilting and abscission of flowers and young fruits of of red cartridge kiwifruit trees in Faer, Houchang, Miluo, Shunchang, Panlong, shaomi, Jichang and Aga bases blooming and pollinating before March 24, but the flowers of red cartridge kiwifruit trees in Langdai, Longhe, Pugu and Shuangfeng bases blooming and pollinating after March 28 were not damaged. [ABSTRACT FROM AUTHOR]

High-temperature stress can cause serious abiotic damage that limits the yield and quality of rice. Heat tolerance (HT) during the flowering stage of rice is a key trait that can guarantee a high and stable yield under heat stress. HT is a complex trait that is regulated by multiple quantitative trait loci (QTLs); however, few underlying genes have been fine mapped and cloned. In this study, the F2:3 population derived from a cross between Huanghuazhan (HHZ), a heat-tolerant cultivar, and 9311, a heat-sensitive variety, was used to map HT QTLs during the flowering stage in rice. A new major QTL, qHTT8 , controlling HT was identified on chromosome 8 using the bulked-segregant analysis (BSA)-seq method. The QTL qHTT8 was mapped into the 3,555,000–4,520,000 bp, which had a size of 0.965 Mb. The candidate region of qHTT8 on chromosome 8 contained 65 predicted genes, and 10 putative predicted genes were found to be associated with abiotic stress tolerance. Furthermore, qRT-PCR was performed to analyze the differential expression of these 10 genes between HHZ and 9311 under high temperature conditions. LOC_Os08g07010 and LOC_Os08g07440 were highly induced in HHZ compared with 9311 under heat stress. Orthologous genes of LOC_Os08g07010 and LOC_Os08g07440 in plants played a role in abiotic stress, suggesting that they may be the candidate genes of qHTT8. Generally, the results of this study will prove useful for future efforts to clone qHTT8 and breed heat-tolerant varieties of rice using marker-assisted selection. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Research & Applications in Agricultural Engineering is the property of Lukasiewicz Research Network - Industrial Institute for Agricultural Machinery and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heracleum persicum, commonly named Persian hogweed, is a principal native medicinal plant in Iran. Collecting H. persicum at the most appropriate growing stage is the key factor to achieve the high phytochemical quality to meet consumer's needs. In the present experiment, the aerial parts of this plant were harvested at up to six different developmental stages during the growing season to determine the phytochemical profiles. Our results indicated that the highest essential oil content was obtained in the mid‐mature seed stage (3.5%). The most elevated extract content was recorded in the floral budding stage (10.4%). In the vegetative stage, limonene (18.1%), in floral budding stage, caryophyllene (14.1%), anethole (14.6%), and β‐bisabolene (12.7%), in the full flowering stage, myristicin (15.0%), and hexyl butyrate (9.1%), in the early development of seeds stage, hexyl butyrate (32.1%), and octyl acetate (11.7%), in the mid‐mature seeds stage hexyl butyrate (38.8%), octyl acetate (14.5%), in the late‐mature/ripe seeds stage, hexyl butyrate (23.6%), and octyl acetate (10.5%) are recorded as the main components. The highest phenolic acids content was obtained in the floral budding stage (287.40 mg/g dried extract). The analysis of phenolic acids demonstrated cinnamic acid (8.0–225.3 mg/g extract), p‐coumaric acid (1.7–39.2 mg/g extract), p‐hydroxybenzoic acid (0.8–16.8 mg/g extract), and ferulic acid (2.4–15.8 mg/g extract) as the main phenolic acids. Cinnamic acid was found as the major phenolic compound in the vegetative stage following by floral budding, the full flowering stage, the early development of seeds, and late‐mature/ripe seeds stages. P‐coumaric acid was the most abundant phenolic compounds in the mid‐mature seeds stage. In this regard, the harvest time of H. persicum aerial parts can be selected to achieve the highest secondary metabolites of interest. The results of this study can be used as a guideline for grower to obtain the highest possible amount of desirable metabolites, beneficial in both food and pharmaceutical industries as well as their undeniable economical benefits. [ABSTRACT FROM AUTHOR]

A field study was conducted to quantify the effect of moisture stress on nutrient uptake and post-harvest available soil nutrient status of rice in Tamil Nadu Agricultural University, Coimbatore during Kuruvai (July-November) 2019 and Navarai (December-March) 2019-20 seasons. Nine treatments, viz., Moisture stress at panicle initiation stage for 10 days (T1), 15 days (T2), 20 days (T3) and 25 days (T4), moisture stress at flowering stage for 10 days (T5), 15 days (T6), 20 days (T7) and 25 days (T8) along with control - maintaining saturation (T9) were tested under randomized complete block design with three replications. Moisture stress was imposed by withdrawing water and not irrigating in the defined period. The result showed that significantly higher total drymatter production and N, P and K nutrient uptake (grain, straw and total) during both the seasons were observed in T9 treatment than all other moisture stress imposed treatments. The least uptake of N, P and K in grain, straw and total was recorded in T4 and was statistically at par with T3. There was reverse trend on post-harvest soil nutrient status (NPK). The study revealed that moisture stress was more sensitive during panicle initiation stage than flowering stage, which directly influenced the uptake of nutrients in rice and there was a reverse trend on post-harvest soil available nutrients (NPK). [ABSTRACT FROM AUTHOR]

Field investigation on the influence of soil moisture stress (MS) on leaf temperature of rice at 0600 hours was made in Tamil Nadu Agricultural University, Coimbatore during Kuruvai (July-November) 2019 and Navarai (December-March) 2019-20 seasons. The treatments are T1: MS for 10 days from PI, T2: MS for 15 days from PI, T3: MS for 20 days from PI, T4: MS for 25 days from PI, T5: MS for 10 days from flowering, T6: MS for 15 days from flowering, T7: MS for 20 days from flowering, T8: MS for 25 days from flowering and T9: Control (Maintaining 2cm of water throughout the crop period). The experiment was laid-out in Randomized Completely Block Design with three replications. Leaf temperature was measured using an infrared thermometer at 0600 hours. Moisture stress had a significant influence on the leaf temperature of rice in the early morning hours. In Kuruvai season, an increase in leaf temperature was to the tune of 0.13oC to 2.20oC during Panicle Initiation (PI) stage (T1, T2, T3 and T4) and 0.16oC to 2.27oC during flowering stage (T5, T6, T7 and T8) over control due to MS. Similarly, increased leaf temperature to the tune of (0.13oC to 2.97oC and 0.07oC to 2.96oC during PI stage and flowering stage, respectively) was observed due to MS treatments than MS relieved treatments and control during Navarai season. The results confirmed that the direct influence on leaf temperature of rice was due to MS irrespective of the stages and seasons. The correlation between grain yield and leaf temperature due to the MS was found to be negative. [ABSTRACT FROM AUTHOR]

The response of compensatory growth is an important adaptive strategy for plants to grazing. However, most previous studies on compensatory growth of plants focused on the compensation of the biomass or the number of sexual reproductive offspring and neglected the compensatory growth of vegetative reproduction (VR). This is important not only for plant compensatory growth studies, but also for theoretical and practical studies of grassland production. The clonal tussock grass Hordeum brevisubulatum was selected as the research object. Four different clipping severities (unclipping and clipping stubble at heights of 15, 10, and 5 cm) at the jointing stage and flowering stage were implemented to study the effect of simulated grazing. To explore the effect of recovery growth time on plant growth after simulated grazing, three sampling times were used at different recovery times after simulated grazing (1, 3, and 7 weeks). We found that light and moderate grazing severity significantly increased the number of vegetative reproduction modules, the promotion of simulated grazing on the number of vegetative reproduction modules was higher in the jointing stage than the flowering stage, and the increase in simulated grazing severity decreased with prolonged recovery growth time. The number of tillers significantly decreased with the increase in simulated grazing in both the jointing and flowering stages at 1 week after damage, and the decreasing effect weakened with the prolonged recovery growth time. The bud number mainly showed over-compensation, the juvenile tiller number showed complete compensation, and the tiller number showed under-compensation at 1 and 3 weeks after recovery growth. The number of tillers showed complete compensation under different grazing severities in the jointing stage, while it showed under-compensation in the flowering stage at 7 weeks after recovery growth. Our results indicated that different grazing severities in the jointing stage could promote the output of tillers with matter production capacity from vegetative reproduction modules, as well as improve the capability of compensatory growth. Therefore, in plant production, there will be a sustainable development effect on the renewal and productivity of the H. brevisubulatum population, resulting in different grazing severities in the jointing stage. [ABSTRACT FROM AUTHOR]

Background: This study was aimed at investigating the possible anti-inflammatory and cytotoxic effects of extracts from the flowering stage of C. argentea. This growth stage was chosen because of its high polyphenolic content and high antioxidant capacity. Methods: Anti-inflammatory potential of the aqueous, acetone and methanol extracts of C. argentea was evaluated through the inhibition of nitric oxide production (LPS-induced) on stimulated macrophages (RAW 264.7), while MTT assay was used to assess cell viability with Silymarin as standard. Cytotoxicity of the plant extracts was evaluated on murine preadipocyte cell line (3 T3-L1) using the image-based method of two DNA-binding dyes; Hoechst 33342 and propidium iodide (PI) with melphalan as standard. Results: Acetone extract exhibited moderate, dose-dependent anti-inflammatory activity with no significant toxicity to activated macrophages, however the aqueous and methanol extracts were unable to inhibit nitric oxide production at both trials. MTT assay and the toxicity assay revealed that the flowering stage extracts of C. argentea were not toxic to the RAW 264.7 macrophages and 3 T3-L1 cells at all the tested concentrations (0, 2, 50, 100 and 200 µg/mL). Conclusions: These findings corroborate the traditional use of C. argentea for painful inflammatory conditions and encourage its possible use as lead for the development of novel, non-toxic, anti-inflammatory agents. [ABSTRACT FROM AUTHOR]

Main conclusion: The present study shows that salt tolerance in the reproductive stage of rice is primarily governed by the selective Na+ and K+ transport from the root to upper plant parts. Ionic discrimination at the flag leaf, governed by differential expression of Na+- and K+-specific transporters/ion pumps, is associated with reduced spikelet sterility and reproductive stage salt tolerance. Reproductive stage salt tolerance is crucial in rice to guarantee yield under saline condition. In the present study, differential ionic selectivity and the coordinated transport (from root to flag leaf) of Na+ and K+ were investigated to assess their impact on reproductive stage salt tolerance. Four rice genotypes having differential salt sensitivity were subjected to reproductive stage salinity stress in pots. The selective Na+ and K+ transport from the root to upper plant parts was observed in tolerant genotypes. We noticed that prolonged salt exposure did not alter flag leaf greenness even up to 6 weeks; however, it had a detrimental effect on panicle development especially in the salt-susceptible genotype Sabita. But more precise chlorophyll fluorescence imaging analysis revealed salinity-induced damages in Sabita. The salt-tolerant genotype Pokkali (AC41585), a potential Na+ excluder, managed to sequester higher Na+ load in the roots with little upward transport as evident from greater expression of HKT1 and HKT2 transporters. In contrast, the moderately salt-tolerant Lunidhan was less selective in Na+ transport, but possessed a higher capacity to Na+ sequestration in leaves. Higher K+ uptake and tissue-specific redistribution mediated by HAK and AKT transporters showed robust control in selective K+ movement from the root to flag leaf and developing panicles. On the contrary, expressions of Na+-specific transporters in developing panicles were either down-regulated or unaffected in tolerant and moderately tolerant genotypes. Yet, in the panicles of the susceptible genotype Sabita, some of the Na+-specific transporter genes (SOS1, HKT1;5, HKT2;4) were upregulated. Apart from the ionic regulation strategy, cellular energy balance mediated by different plasma-membrane and tonoplastic H+-pumps were also associated with the reproductive stage salt tolerance in rice. [ABSTRACT FROM AUTHOR]

Total 20 maize varieties were subjected to drought stress at flowering stage, and then the relative water content, soluble sugar content, chlorophyll content, malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in their leaves, as well as their yields were determined. The drought tolerance of the physiological and biochemical indexes was scored by five-level scoring method, and the drought tolerance index was calculated by the yield index to comprehensively evaluate the drought tolerance of maize during flowering stage. The results showed that the scores of drought tolerance of the maize varieties ranged from 1. 929 3 to 5.659 5. Among them, the scores of Zhengda 619, Guidan 162 and Guidan 0810 were greater than 5.0, followed by Dika 008, Xianyu 30T60, Xianzhengda 901, Qingnong 68, South America No. 1 and Wanchuan 1306 of which the scores were in the range of 4.0 -5.0. The drought tolerance indexes were in the range of 0.410 4 - 1.096 3. Among the test maize varieties, the drought tolerance indexes of Guidan 0810, Pacific 99 and Zhengda 619 were greater than 1.0, and those of Xianyu 30T60, Dika 008 and South America No. 1 were in the range of 0. 9 -1.0. The correlation between the two kinds of evaluation results was 0. 588 7 and was extremely significant. The five-level scoring method and the drought tolerance index can be used simultaneously for the evaluation of drought tolerance of maize during flowering stage. The two aspects of evaluation results showed that Guidan 0810, Zhengda 619, Xianyu 30T60, Dika 008 and South America No. 1 were drought-tolerant varieties, among which Guidan 0810 and Zhengda 619 were extremely highly drought-tolerant varieties. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Salt stress, a major plant environmental stress, is a critical constraint for rice productivity. Dissecting the genetic loci controlling salt tolerance in rice for improving productivity, especially at the flowering stage, remains challenging. Here, we conducted a genome-wide association study (GWAS) of salt tolerance based on exome sequencing of the Thai rice accessions. Results: Photosynthetic parameters and cell membrane stability under salt stress at the flowering stage; and yield-related traits of 104 Thai rice (Oryza sativa L.) accessions belonging to the indica subspecies were evaluated. The rice accessions were subjected to exome sequencing, resulting in 112,565 single nucleotide polymorphisms (SNPs) called with a minor allele frequency of at least 5%. LD decay analysis of the panel indicates that the average LD for SNPs at 20 kb distance from each other was 0.34 (r2), which decayed to its half value (~ 0.17) at around 80 kb. By GWAS performed using mixed linear model, two hundred loci containing 448 SNPs on exons were identified based on the salt susceptibility index of the net photosynthetic rate at day 6 after salt stress; and the number of panicles, filled grains and unfilled grains per plant. One hundred and forty six genes, which accounted for 73% of the identified loci, co-localized with the previously reported salt quantitative trait loci (QTLs). The top four regions that contained a high number of significant SNPs were found on chromosome 8, 12, 1 and 2. While many are novel, their annotation is consistent with potential involvement in plant salt tolerance and in related agronomic traits. These significant SNPs greatly help narrow down the region within these QTLs where the likely underlying candidate genes can be identified. Conclusions: Insight into the contribution of potential genes controlling salt tolerance from this GWAS provides further understanding of salt tolerance mechanisms of rice at the flowering stage, which can help improve yield productivity under salinity via gene cloning and genomic selection. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To evaluate the effects of methanol concentration (0, 20, 40 and 60% v/v) and application time (before and after flowering) on yield and some morphological characteristics of sesame, a field experiment was performed at the research field of Jiroft University in 2016. Treatments were arranged in a factorial based on a randomized complete block design with four replications. Based on results, Methanol concentration had significant effects on all studied characteristics, so that the highest and lowest mean value was observed at 40% methanol concentration and control, respectively. Methanol spraying time significantly influenced the stem diameter, seed number, harvest index and 1000-seed weight, so that the highest and lowest means were obtained at before and after flowering stages, respectively. The interaction of methanol concentration and methanol spraying time were significant on leaf area index, leaf number, length branches, number of lateral branches, number of capsules, seed number, plant height, shoot dry weight and seed yield. The best treatment in this study was foliar application of 40% methanol concentration at pre-flowering stage. According to the results, it can be concluded that the use of methanol could greatly improve the yield, and morphological characteristics of sesame. [ABSTRACT FROM AUTHOR]

The present study reports an unequivocal and improved protocol for efficient screening of salt tolerance at flowering stage in rice, which can aid phenotyping of population for subsequent identification of QTLs associated with salinity stress, particularly at reproductive stage. To validate the new method, the selection criteria, level and time of imposition of stress; plant growth medium were standardized using three rice genotypes. The setup was established with a piezometer placed in a perforated pot for continuous monitoring of soil EC and pH throughout the period of study. Further, fertilizer enriched soil was partially substituted by gravels for stabilization and maintaining the uniformity of soil EC in pots without hindering its buffering capacity. The protocol including modified medium (Soil:Stone, 4:1) at 8 dS m−1 salinity level was validated using seven different genotypes possessing differential salt sensitivity. Based on the important selection traits such as high stability index for plant yield, harvest index and number of grains/panicle and also high K+ concentration and low Na+- K+ ratio in flag leaf at grain filling stage were validated and employed in the evaluation of a mapping population in the modified screening medium. The method was found significantly efficient for easy maintenance of desired level of soil salinity and identification of genotypes tolerant to salinity at reproductive stage. [ABSTRACT FROM AUTHOR]