Bloom Stage Research Articles

Study of the Relationship between Biomass and Fractional Green Canopy Cover of Two Forage Crops Using Canopeo®

Rapid and accurate estimation of biomass is crucial for the assessment of the crop nutrition status and the improvement of crop management strategies. The study was conducted in Setif province (Northeast of Algeria). Canopy cover was calculated using Canopeo® application, at stem elongation, booting, and heading stages for triticale, and V5, R1, and R3 for lentil. The results indicate a high correlation between canopy cover and triticale biomass, at the stem elongation stage with R2 = 0.98 and 0.89 under no till and conventional till, respectively. The RMSE was 0.1 and 0.06t/ha, under the two modes. The lowest correlation is seen at heading stage with a value of 0.21 and RMSE of 0.65t/ha, under no till mode. For lentil, the high correlations between are observed at R3 (early pod), and R1 (early bloom) stages, with a coefficients of 0.85 and 0.98, under zero till and conventional respectively. The RMSE was 0.17t/ha. This smartphone application is suitable for assessing triticale and lentil biomass; it is rapid, easy, and could replace the destructive sampling method.

Plow layer management during the fallow season can enhance the wheat productivity and resource utilization in a semi-arid region

The soil quality is poor in the arid areas of Northwest China and planting green manure can improve the soil quality but it also increases the soil water consumption. Straw mulching in the wheat (Triticum aestivum L.) fallow season can improve the soil water content. It is unclear whether green manure can be planted in addition to straw mulching to improve the soil water content and quality. Therefore, a field experiment was conducted in the semi-arid area of the Loess Plateau in China from 2009 to 2017 with the following treatments; (1) traditional bare land in fallow season after plowing (CK), (2) no-tillage with straw mulching (NTSM), (3) and no-tillage with straw mulching and planting soybean as green manure (NTSGM). We determined the effects of these three treatments on the soil water, nutrients, and wheat productivity. Compared with CK, the average soil water contents in 0–100 cm soil depth increased by 11.1% and 3.6% under NTSM and NTSGM, respectively, during the soybean full bloom stage, and by 13.06% and 6.6% before wheat sowing. Compared with CK, the decomposition of green manure increased the NO3–-N contents in the 0–100 cm soil depth by 6.6% and 5.3% under NTSGM before wheat sowing and after harvesting, respectively, and NTSM and NTSGM significantly improved the soil nutrients, microbial biomass contents, and enzyme activities. The superior soil quality and water content under NTSM and NTSGM increased the fertilizer uptake and partial factor productivity. Compared with CK, the average precipitation storage efficiency, water use efficiency during the whole year, biomass, and wheat yield were 32.6%, 23.2%, 16.2%, and 21.6% higher under NTSGM, respectively. Therefore, NTSGM is an effective method for improving the soil water storage and NO3–-N contents before sowing wheat, as well as the water use efficiency, soil quality, utilization of nutrients, and wheat productivity in semi-arid areas of the Loess Plateau.

PRIMARY PRODUCERS SIZE STRUCTURE IN THE MARGINAL ICE ZONE OF EUROPEAN ARCTIC IN SUMMER

Primary production (PP) and chlorophyll “a” concentration (chl “a”) estimates in the Eurasian Arctic are discussed, where the continued climatic warming with increased “Atlantification” advance the sea ice losses. The maximum integrated PP and the total chl “a” content observed in the marginal ice zone (MIZ) of the Barents Sea with weakened stratification of the water column and reached 1109 mgC m–2 day–1 and 118 mg m–2. Nearby the ice edge in the Nansen Basin, the main part of PP formed in the upper mixed layer and did not exceed 469 mgC m–2 day–1, the chl “a” content of 56 mg m–2. In the early and late phytoplankton bloom in MIZ, the typical leading role of picophytoplankton in carbon fixation revealed. Large centric diatoms, microphytoplankton, dominated at the peak bloom stage in 2020 with the dense marine ice cover of the Nansen Basin. A similar phenomenon was previously observed only in the Arctic shelf seas and was not recorded in the high-latitude basins of the Arctic Ocean. With the sparse ice cover of the Nansen Basin in 2021, the main primary producers at the peak bloom were pico- and nanophytoplankton. The low variability of assimilation numbers at all bloom stages (1.7 ± 0.3 mgC mg chl “a”–1 h–1) indicates the acclimatization of phytoplankton to changing environment. The ecological flexibility of the primary production are link of the MLZ ecosystems in the studied seas of the European Arctic during the period of climate change is confirmed.

Marigold Flower Blooming Stage Detection in Complex Scene Environment using Faster RCNN with Data Augmentation

In recent years, flower growing has developed into a lucrative agricultural sector that provides employment and business opportunities for small and marginal growers in both urban and rural locations in India. One of the most often cultivated flowers for landscaping design is the Marigold flower. It is also widely used to create garlands for ceremonial and social occasions using loose flowers. Understanding the appropriate stage of harvesting for each plant species is essential to ensuring the quality of the flowers after they have been picked. It has been demonstrated that human assessors consistently used a category scoring system to evaluate various flowering stages. Deep learning and convolutional neural networks have the potential to revolutionize agriculture by enabling efficient analysis of large-scale data. In order to address the problem of Marigold flower stages detection and classification in complex real-time field scenarios, this study proposes a fine-tuned Faster RCNN with ResNet50 network coupled with data augmentation. Faster RCNN is a popular deep learning framework for object detection that uses a region proposal network to efficiently identify object locations and features in an image. The Marigold flower dataset was collected from three different Marigold fields in the Anand District of Gujarat State, India. The collection includes of photos that were taken outdoors in natural light at various heights, angles, and distances. We have developed and fine-tuned a Faster RCNN detection and classification model to be particularly sensitive to Marigold flowers, and we have compared the generated method's performance to that of other cutting-edge models to determine its accuracy and effectiveness.

Accumulation patterns of major bioactive components in two chemotypes of Agastache rugosa during flower development evaluated by GC-QQQ-MS/MS and UPLC-QTOF-MS/MS analyses

Agastache rugosa (AR) is a wildly cultivated medicinal and aromatic crop, which usually recommended to be harvested when the plant is exuberant with not flowering or in full flower stage. But there is no scientific basis for the support of the cognition. Therefore, the accumulation patterns of major active components during flower development (inflorescences with buds, full bloom and after full bloom stages) in two chemotypes (menthone type and estragole type) of AR were investigated by newly developed GC–QQQ–MS/MS and UPLC–QTOF–MS/MS methods. Five volatile (pulegone, menthone, estragole, methyleugenol and β -caryophyllene) and nine non-volatile components (rosmarinic acid, tilianin, acacetin 7- O -(6"- O -malonyl)- β - D -glucopyranoside, apigenin, agastachoside, isoagastachoside, acacetin 7- O -(2"- O -acetyl-6"- O -malonyl)- β - D -glucopyranoside, cirsimaritin and acacetin) in two chemotypes of AR samples at three stages were simultaneously quantified. It was found that the relatively higher contents of main volatile components were present in menthone type of AR collected at the full flower stage and in estragole type of AR at the after full bloom stage, whereas the relatively higher contents of main non-volatile components were present in menthone type of AR collected at the inflorescences with buds stage and in estragole type of AR at the after full bloom stage. Considering major active volatile and non-volatile components with higher levels, full bloom stage and after full bloom stage should be optimal harvesting time for menthone type and estragole type of AR, respectively. • GC–QQQ–MS/MS and UPLC–QTOF–MS/MS methods developed to quantify components of AR. • Both menthone and estragole chemotype AR at flowering stages were investigated. • Accumulation patterns of both volatile and non-volatile components of AR were revealed. • Full bloom and after full bloom stage are optimal harvesting time for menthone and estragole type of AR.

Tapping Carbon Sequestration Potential of Blooming Macroalgae to Mitigate Climate Change

Macroalgal mariculture is gaining global attention to achieve carbon neutrality due to its important contribution to ocean carbon sequestration. However, some wild macroalgal species (e.g., Sargassum and Ulva prolifera ) exhibit strong environmental adaptability and can cause large-scale, recurrent blooms in global oceans, fueled by rising atmospheric CO 2 levels and coastal eutrophication. Notably, massive Ulva prolifera green tides have occurred annually in the Yellow Sea for the past 17 consecutive years. At the late blooming stage, millions of tons of U. prolifera naturally sink to the shallow seafloor. The subsequent intense microbial aerobic degradation of sinking macroalgae results in coastal hypoxia and acidification, with most of the macroalgal carbon returning to the atmosphere. Preventing or reducing the intense degradation of massive sinking U. prolifera could enable more macroalgal carbon storage in the ocean in the long term and alleviate the harmful effects of green tide. Thus, ecological disasters from macroalgal blooms may be transformed into useful natural platforms to increase ocean carbon sequestration. We propose an integrated strategy using environmentally friendly minerals (e.g., montmorillonite and calcium carbonate) and coagulants (e.g., polyaluminum chloride), along with natural algicidal bacteria or substances, to induce rapid flocculation and sedimentation of blooming macroalgae, reduce the degradation of sinking macroalgae and its negative environmental impacts, and minimize the generation of macroalgal propagules or seeds and the potential risk for future green tide outbreaks. This integrated approach is potentially a promising approach to tap the carbon sequestration potential of macroalgal blooms to mitigate climate change.

Alternative Approaches to Chemical Thinning for Regulating Crop Load and Alternate Bearing in Apple

In the past, chemical thinning dominated in fruit orchards. This paper for the special issue outlines alternatives to chemical thinning for crop load management (CLM) and its effect on fruit size, firmness, sugar, starch, and weight, indicating ripeness and fruit quality, yield, and alternate bearing. A total of 450 apple trees (Malus domestica Borkh., cv. ‘Roter Boskoop’; six years old) on M9 rootstock were used at the Klein-Altendorf experimental station (50° N) of the University of Bonn, Germany. As the first alternatives, trees were mechanically blossom-thinned at the balloon stage (BBCH 59) with a rotor speed of 320 rpm or 380 rpm at 5 km/h tractor speed or were chemically thinned at the full bloom stage (BBCH 65) with ammonium thiosulfate (ATS), ethephon (ETH), and/or 6-benzyladenine (BA) at 10–12 mm fruit size (BBCH 71) after applying ATS/ETH. Flower clusters and/or cluster leaves (source) were manually removed to determine the optimum sink-source ratio to achieve different ratios of fruitlets (sink) relative to the leaves (source) at fruit set (BBCH 67–69). Un-thinned, adjacent trees served as the control. The majority of CLM methods improved fruit size and weight. Removing cluster leaves at fruit set increased fruit size and weight of the remaining fruit, which has not been observed before. The most effective treatment for fruit size and weight and return bloom was the 75% flower cluster and complete cluster leaf removal. Removal of more than 50% of flower clusters successfully improved return bloom, indicative of alternate bearing. The mechanical blossom thinning had a positive effect on fruit size and weight with a return bloom similar to that of removal of 50% flower clusters.

Predicting arbuscular mycorrhizal fungal colonization of soybean in farmers’ fields by using infection unit density

ABSTRACT Estimating arbuscular mycorrhizal (AM) fungal activity to colonize crop root before cultivation is prerequisite for effective utilization of their functions which enhance growth and yield of the plant especially under low fertilizer input. We have hypothesized that the infection unit (IU) density formed on test plant roots grown for short period (12 days) with soil sampled from soybean production fields would be an effective indicator to predict AM fungal colonization intensity to the plant. In order to test this hypothesis, three-year farmland survey was conducted, in which soil samples before sowing soybean and the plant root samples at third trifoliate (V3) and full bloom (R2) stage were collected from farmers’ fields in two regions in Hokkaido, Iwamizawa and Tokachi. For each sampling spot, IU density was determined by using test plants, and intensity of AM fungal colonization of soybean root was measured. Before pursuing field survey, laboratory experiments were conducted to find out proper soil storage condition that keeps IU density unchanged while handling many soil samples. Our results indicated that IU density was almost comparable to the original value after six-month storage if soil samples were kept in a refrigerator, although storing at ambient temperature significantly decreased the measurement. Air drying also had negative impact on IU density. According to the field survey, IU densities determined using field soil were positively and significantly correlated with AM fungal colonization of soybean roots at both V3 and R2 stages. Differences in climate, soil type, and style of agriculture between Iwamizawa and Tokachi seemed to have little effect on IU density-AM fungal colonization relationship. Other than IU density, soil pH and soil penetration resistance at 10 cm depth were selected as significant explanatory variables for predicting AM fungal colonization by multiple regression analysis. However, IU density was the most influential factor among three. Therefore, IU density is recognized as an effective measure to evaluate AM fungal colonizing activity in field soil.

Early and Late Season Nutrient Stress Conditions: Impact on Cotton Productivity and Quality

Modern cotton (Gossypium spp. L) cultivars are efficient in nutrient uptake and utilization, and thus, may potentially tolerate nutrient stress. Early- and late-season nutrient stress (E-stress and L-stress, respectively) effects on cotton productivity and quality were assessed under different production conditions in Camilla and Midville, GA, USA. The E-stress received no nutrient application in the early season, but the full rates were split-applied equally at the initiation of squares and the second week of bloom stages. The L-stress received 30–40% of the full nutrient rates only at the initial stage of planting. The effects of nutrient stress on cotton productivity and fiber quality were not consistent across the different production conditions. Compared to the full nutrient rate, the E-stress did not adversely impact cotton yield, but rather it improved the lint and cottonseed yields under one production condition by 17.5% and 19.3%, respectively. Averaged across all production conditions, the L-stress decreased the lint and cottonseed yields by 34.4% and 36.2%, respectively. The minimal effects of E-stress on cotton suggest nutrient rates at the early season could be reduced and more tailored rates, informed by soil and plant tissue analyses, applied shortly before the reproductive phase.

Comparative Study of the Nutritional Value and Degradation Characteristics of Amaranth Hay in the Rumen of Goats at Different Growth Stages.

The objective of this study was to investigate the rumen degradation characteristics of grain amaranth hay (Amaranthus hypochondriacus) at four different growth stages. The aim of this study was to evaluate the nutritional value of grain amaranth hay at different growth stages by chemical composition, in vivo digestibility, and in situ degradability. Three Boer goats with permanent ruminal fistulas were selected in this study. Amaranthus hay at four different growth stages (squaring stage (SS), initial bloom stage (IS), full-bloom stage (FS) and mature stage (MS)) was crushed and placed into nylon bags. Each sample was set up with three replicates, and two parallel samples were set up in fistulas at each time point. The rumen degradation rates of dry matter (DM), crude protein (CP), neutral detergent fibre (NDF) and acid detergent fibre (ADF) were determined at 0, 6, 12, 24, 36, 48 and 72 h. The results were as follows: (1) The concentration of CP in SS was the highest and was significantly higher than that in other stages (p < 0.05), whereas the contents of NDF and ADF gradually increased with the extension of the growing period and reached a maximum in MS; (2)The degradation of CP in the rumen at 72 h of SS and IS was more than 80%. Compared with other stages, the effective degradability of CP was highest in SS (p < 0.05) and reached 87.05% at 72 h, and the degradation rate was the lowest in MS; and (3) The effective degradability of NDF in IS was the highest (p < 0.05) and reached 69.326% at 72 h. The effective degradability of ADF in MS was the highest (p < 0.05) and reached 65.728% at 72 h. The effective degradability of DM and CP in SS was the highest. In conclusion, among the four stages, IS was superior in chemical composition and rumen degradability characteristics.

Field evaluation of automated site-specific irrigation for cotton and perennial ryegrass using soil-water sensors and Model Predictive Control

Variable-rate irrigation technology can reduce water use in centre pivot and lateral move irrigation systems through application of irrigation according to spatially varied soil-water profiles. However, filling the profile may not maximise yield because of variations in crop response and water requirements with crop stage. For example, cotton crops produce optimal yield under slight water stress during early stages. An irrigation strategy ‘Model Predictive Control’ has been implemented that accounts for changes in crop water requirements at different growth stages using biophysical crop models. This strategy involves automatically and iteratively executing the biophysical crop model APSIM parameterised with local soil and weather information, with different irrigation depths, to identify which combination maximises yield with the minimum depth of water application. This strategy has potential to address spatial and temporal variations in crop water requirements but has not previously been evaluated for variable-rate irrigation in the field. This paper reports field trials conducted over four cotton (Gossypium hirsutum L.) seasons and two perennial ryegrass (Lolium. perenne L.) seasons to evaluate the accuracy of the yield prediction of the biophysical model and compare field performance of irrigation strategies: uniform irrigation and variable-rate irrigation using a fixed underlying map, soil-water sensors and Model Predictive Control. Yield was most accurately predicted using on-site weather data and field soil core information, with R² = 0.733 and RMSE = 153.9 kg/ha for cotton, and R² = 0.336 and RMSE = 295.3 kg/ha for ryegrass. For cotton, Model Predictive Control led to 4.9% more yield with 5.6% reduction in water application, mainly through reduced water after peak bloom and/or open boll physiological stages. For grazed ryegrass, the Model Predictive Control strategy led to 8.5% more yield with 5.4% reduction in water application, potentially caused by reduced applications after grazing events. Further work includes evaluating the Model Predictive Control strategy with control of irrigation event timing under a broader range of field conditions to identify parameters to provide greatest economic return, and to refine biophysical models for improved performance of optimisation in the strategy.

Cotard’s Delusion-DEAD MAN’S SKETCH

Cotard’sdelusion (CD) is anerratic psychiatric disorder in which the patient believes to be dead, i.e., the patient holdsnihilistic delusions concerning his/her own existence. Taking into justification its rarity, and possible subdiagnosis dueto inexperience, most of the literature consists of case studies, confounding a more systematic approach and leading tohitches in deciding the best clinical direction to offer the patient misery from CD. The patient eventuallygrieves fromnihilistic delusions that they no lengthier exist. Though the delusional disorder was first recognized in the 17th century byDr. Jules. It is neither classified under DSM-IV-TR nor ICD-10. There is main three main stages of this disease condition:Germination stage, Blooming stage and Chronic stage. Detecting Cotard delusion is habitually difficult because mostorganizations don’t distinguish it as a disease. Patients habitually receive medication and therapy. Medications usedto treat this delusional disorder include: Anti-anxiety, Antidepressants, Antipsychotics, Mood stabilizers medications,Psychotherapy, Play therapy etc. treatment modalitiesNevertheless,Cotard syndrome have been described in connotationwith many other affective disorders, it is less often found in patients with catatonia.

Integrated analysis of miRNAome transcriptome and degradome reveals miRNA-target modules governing floral florescence development and senescence across early- and late-flowering genotypes in tree peony.

As a candidate national flower of China, tree peony has extremely high ornamental, medicinal and oil value. However, the short florescence and rarity of early-flowering and late-flowering varieties restrict further improvement of the economic value of tree peony. Specific miRNAs and their target genes engaged in tree peony floral florescence, development and senescence remain unknown. This report presents the integrated analysis of the miRNAome, transcriptome and degradome of tree peony petals collected from blooming, initial flowering, full blooming and decay stages in early-flowering variety Paeonia ostii 'Fengdan', an early-flowering mutant line of Paeonia ostii 'Fengdan' and late-flowering variety Paeonia suffruticosa 'Lianhe'. Transcriptome analysis revealed a transcript ('psu.G.00014095') which was annotated as a xyloglucan endotransglycosylase/hydrolase precursor XTH-25 and found to be differentially expressed across flower developmental stages in Paeonia ostii 'Fengdan' and Paeonia suffruticosa 'Lianhe'. The miRNA-mRNA modules were presented significant enrichment in various pathways such as plant hormone signal transduction, indole alkaloid biosynthesis, arachidonic acid metabolism, folate biosynthesis, fatty acid elongation, and the MAPK signaling pathway. Multiple miRNA-mRNA-TF modules demonstrated the potential functions of MYB-related, bHLH, Trihelix, NAC, GRAS and HD-ZIP TF families in floral florescence, development, and senescence of tree peony. Comparative spatio-temporal expression investigation of eight floral-favored miRNA-target modules suggested that transcript 'psu.T.00024044' and microRNA mtr-miR166g-5p are involved in the floral florescence, development and senescence associated agronomic traits of tree peony. The results might accelerate the understanding of the potential regulation mechanism in regards to floral florescence, development and abscission, and supply guidance for tree peony breeding of varieties with later and longer florescence characteristics.

Mask R-CNN based apple flower detection and king flower identification for precision pollination

Identification of individual king flowers within flower clusters is a critical step for developing a robotic apple pollination system. Typically, each cluster has five to six individual flowers, and the king flower can be occluded by the lateral flowers because of their central position in a flower cluster. King flowers share identical features (e.g., color, shape, and size) with other flowers. Apple flower clusters open sequentially from the king flower to the lateral flowers in the time of anthesis, which presents an opportunity for selective pollination. Therefore, it is critical to monitor the flower blooming stage for accurately determining the pollination targets and timing. In this study, a machine vision system was developed to acquire images for two apple varieties in the orchard environment. A Mask R-CNN-based detection model followed by a king flower segmentation algorithm were developed to identify and locate the king flowers from an apple flower dataset throughout the blooming stage from first king bloom to full bloom. The flower detection accuracy resulting from the algorithm were compared with ground truth measurements. The king flower detection accuracy varied from 98.7% to 65.6% with respect to the flower stages of 20% to 80% blooming. This information can be used to calculate the percentage of the king flowers and the distribution in the tree canopy. Along with horticultural knowledge, the outcome from the study is expected to provide decision-making information for robotic pollination.

Lavandula angustifolia Mill. a model of aromatic and medicinal plant to study volatile organic compounds synthesis, evolution and ecological functions

ABSTRACT Lavandula angustifolia Mill. or true lavender is an emblematic plant from dry and calcareous hills of the south of France. Lavender essential oils obtained from inflorescences harvested at bloom stage are mainly composed of monoterpenes and few sesquiterpenes. The characteristic lavender smell is due to linalool and linalyl acetate that represent more than half of the emitted volatile organic compound (VOC) quantity. These monoterpenoids are derived from plastidial pathway precursors. The regulation of this pathway in lavender is mainly managed by the successive expression of two DXS during flower development. In the light of 10 years of published data on lavender, it appears that biochemical pathways of main terpenes are mostly depicted. Several transcriptomic libraries are available and a genome at chromosome scale has been assembled and molecular markers developed. The diversity of lavender terpenes and their biosynthesis are reviewed with additional original data regarding the anatomical glandular structures and expression of genes involved in IPP biosynthesis.

Root-Zone Restriction Regulates Soil Factors and Bacterial Community Assembly of Grapevine.

Root-zone restriction induces physiological stress on roots, thus limiting the vegetative and enhancing reproductive development, which promotes fruit quality and growth. Numerous bacterial-related growth-promoting, stress-mitigating, and disease-prevention activities have been described, but none in root-restricted cultivation. The study aimed to understand the activities of grapevine bacterial communities and plant-bacterial relationships to improve fruit quality. We used High-throughput sequencing, edaphic soil factors, and network analysis to explore the impact of restricted cultivation on the diversity, composition and network structure of bacterial communities of rhizosphere soil, roots, leaves, flowers and berries. The bacterial richness, diversity, and networking were indeed regulated by root-zone restriction at all phenological stages, with a peak at the veraison stage, yielding superior fruit quality compared to control plants. Moreover, it also handled the nutrient availability in treated plants, such as available nitrogen (AN) was 3.5, 5.7 and 0.9 folds scarcer at full bloom, veraison and maturity stages, respectively, compared to control plants. Biochemical indicators of the berry have proved that high-quality berry is yielded in association with the bacteria. Cyanobacteria were most abundant in the phyllosphere, Proteobacteria in the rhizosphere, and Firmicutes and Bacteroidetes in the endosphere. These bacterial phyla were most correlated and influenced by different soil factors in control and treated plants. Our findings are a comprehensive approach to the implications of root-zone restriction on the bacterial microbiota, which will assist in directing a more focused procedure to uncover the precise mechanism, which is still undiscovered.

Essential oil yield and composition of Ocimum basilicum L. at different phenological stages, plant density and post-harvest drying methods

• CIM-Sukhda is a linalool rich cultivar of basil. • Densely grown plants have better height and canopy • Higher amount of essential oil is produced in full bloom stage • Post harvest drying methods influence essential oil composition Ocimum basilicum L., popularly known as "sweet basil," is native to South Africa, America, and Asia. In India, numerous cultivars and varieties of O. basilicum have been released for commercial cultivation, which are rich in specific essential oils. In this study, the effects of phenological stages and plant density on the productivity of high-quality essential oil of CIM-Sukhda cultivar of O. basilicum and the effects of drying methods on essential oil quality were investigated. In the present study, four plant spacing (45cm × 30cm, 45cm × 40cm, 45cm × 45cm, 45cm × 60cm), four growth stages (vegetative, semi-flowering, full flowering and seed formation) and drying up to one month were compared. A total of 20 compounds were identified by GC and GC-MS, with linalool (66.9-84.2%), geranial (1.1-9.0%), neral (0.8-7.0%) and 1,8-cineole (0.5-3.4%) as the main constituents. The results showed that both plant density and growth stages affected herb and essential oil yield. The essential oil yield of CIM-Sukhda plants is higher at the time of full flowering (106.2 kg ha −1 ) with > 75.0% linalool content in the essential oil.

Geological Distribution of the Miocene Carbonate Platform in the Xisha Sea Area of the South China Sea, and Its Implications for Hydrocarbon Exploration

The newly collected seismic data and the existing drilling data provide a good opportunity to better understand the carbonate platform distribution characteristics and the hydrocarbon resource potential in the Xisha sea area of the South China Sea. Based on the seismic data and the reflection characteristics of the carbonate platform’s edge, three boundary indicators were established: abrupt lithological interfaces, fault interfaces, and tidal channels. Combined with the regional geological settings, its spatial and temporal distribution was clearly identified for the first time. The development of the Miocene carbonate platform in the Xisha sea area is divided into six phases, which are further assigned to three evolutionary stages: the bloom stage, the recession stage, and the submerged stage. The sedimentary facies belt of the carbonate platform in each stage is well developed, and the reefs are mainly distributed on the west and southwest edges of the platform. The analysis of the data indicates that the area of the reef and carbonate platform reached 80,000 km2 during the mature period, followed by a retreat period where the scale decreased with the platform’s decline. The Miocene carbonate rocks in the Xisha sea area are widely distributed. They have experienced multiple periods of exposure and infiltration, which further improved the quality of their physical properties for hydrocarbon reservoirs. According to the regional hydrocarbon geological conditions in this area—including the source rock, migration system and the capping layer—the hydrocarbon accumulation potential is preliminarily discussed in this paper. A reservoir model of the reef and carbonate platform is established, which is proposed as typical characteristics of “lower generation, upper accumulation”. It is pointed out that the carbonate platform in the Xisha sea area adjacent to the Huaguang Sag in the Qiongdongnan Basin and the northern Zhongjiannan Basin is a potential area for oil and gas exploration.

Exploring the Molecular Mechanism of Sepal Formation in the Decorative Flowers of Hydrangea macrophylla 'Endless Summer' Based on the ABCDE Model.

With its large inflorescences and colorful flowers, Hydrangea macrophylla has been one of the most popular ornamental plants in recent years. However, the formation mechanism of its major ornamental part, the decorative floret sepals, is still not clear. In this study, we compared the transcriptome data of H. macrophylla 'Endless Summer' from the nutritional stage (BS1) to the blooming stage (BS5) and annotated them into the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) databases. The 347 identified differentially expressed genes (DEGs) associated with flower development were subjected to a trend analysis and a protein-protein interaction analysis. The combined analysis of the two yielded 60 DEGs, including four MADS-box transcription factors (HmSVP-1, HmSOC1, HmAP1-2, and HmAGL24-3) and genes with strong connectivity (HmLFY and HmUFO). In addition, 17 transcription factors related to the ABCDE model were screened, and key candidate genes related to the development of decorative floret sepals in H. macrophylla were identified by phylogenetic and expression pattern analysis, including HmAP1-1, HmAP1-2, HmAP1-3, HmAP2-3, HmAP2-4, and HmAP2-5. On this basis, a gene regulatory network model of decorative sepal development was also postulated. Our results provide a theoretical basis for the study of the formation mechanism of decorative floret sepals and suggest a new direction for the molecular breeding of H. macrophylla.

Modeling of P-Loss Risk and Nutrition for Mango (Mangifera indica L.) in Sandy Calcareous Soils: A 4-Years Field Trial for Sustainable P Management

The continuous addition of phosphorus (P) fertilizers above plant requirements increases P loss risks, especially if such fertilization practices continue long-term. The current study aims to determine the threshold value of P in plants and soil, which achieves the maximum mango fruit yield without P loss risk. P fertilizer doses (0–240 g tree−1) were added to 12-year-old mango (Mangifera indica L.) cv Hindy planted in sandy soil for four consecutive years. Soil and plant samples were collected each year to estimate the critical p values by linear–linear, quadratic, and exponential models. The relationships between fruit yield and available soil P were positive and significant in all the mathematical models. Mango fruit yield is expected to reach its maximum value if the sandy calcareous soil contains an available P amount ranging between 10–12 mg kg−1 and increasing the soil available P above this level leads to negligible increases in the fruit yield. Increasing the available soil P above 20.3 mg kg−1 increases P-loss risk. P concentrations in blades and petioles of mango leaves can be arranged as follows: beginning of the flowering stage &gt; the full blooming stage &gt; beginning of the fruiting stage. The analysis of petioles of mango leaves in the beginning of the flowering stage significantly corelated with mango fruit yield and can be used in predicting the response of mango to P fertilization. The findings of the present investigation revealed that the critical P in mango petioles ranged between 2.34 and 3.53 g kg−1. The threshold of available soil P for maximum fruit yield is half of P loss risks. The combined analysis of soil and plants is a powerful diagnostic tool for P management in sandy degraded soil. The findings of the current study are a good tool in achieving the optimum utilization of P fertilizer resources in maximizing mango fruit yield and reducing the risks of environmental pollution that result from excessive fertilization doses.