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DOAJ Open Access 2026
Comparative Transcriptomics Reveals Important Genes Underlying Heat-Tolerant Sterility in Photo-Thermo-Sensitive Male Sterile Wheat in Seed Production Environments

Jieru Yue, Shaohua Yuan, Qiling Hou et al.

Maintaining stable male sterility is fundamental for ensuring the genetic purity and productivity of two-line hybrid wheat. However, unexpected heat events during the fertility-sensitive period can induce fertility restoration in photo-thermo-sensitive male sterile (PTMS) lines, posing a major threat to hybrid seed production. In this study, we identified two BS-type PTMS lines, BS166 and BS192, that consistently maintained sterility under heat stress in a seed-production environment, indicating strong heat-tolerant sterility. To uncover the molecular basis underlying this stability, we compared four BS-type PTMS lines exhibiting contrasting heat responses through field assessments, controlled heat treatments, transcriptome sequencing, and weighted gene co-expression network analysis (WGCNA). A total of 19,105 differentially expressed genes were identified, with the bisque4 module showing a significant correlation with seed setting rate. KEGG enrichment analysis revealed that starch and sucrose metabolism, cutin, suberin, and wax biosynthesis, fatty acid biosynthesis, and plant hormone signal transduction pathways were highly associated with heat-tolerant sterility. Core genes within these pathways displayed transcriptional stability in BS166 and BS192 but were strongly induced in heat-sensitive lines. In situ hybridization and RT-qPCR further confirmed tapetum-specific expression of <i>TaBGLU32</i> and <i>TaLACS1</i>. Based on these findings, we propose a regulatory model explaining how PTMS lines maintain sterility stability under heat stress.

DOAJ Open Access 2025
Effects of Hydrothermal-Chemical Treatments on Bending Performance and Physical-Mechanical Properties of Four Timber Species

Huajie Shen, Caixia Bai, Fengwu Zhang et al.

The bending behavior of four key timber species (Fraxinus chinensis, teak, rubberwood, and Pinus yunnanensis) was evaluated under hydrothermal-chemical treatments. Controlled experiments at varying moisture contents (20 to 60%), temperatures (100 to 140 °C), and treatment durations (4 to 8 h) revealed that bending strength and elastic modulus decreased by 18 to 32% with increased moisture and temperature, stabilizing beyond critical thresholds (40% moisture, 120 °C). Among the treatments, the compound lye (40% ammonia + 5% ethylenediamine with surfactants) outperformed ammonia and water treatments, achieving the highest bending deformation height-to-radius ratio of 0.102. X-ray diffraction and Fourier-transform infrared spectroscopy analyses confirmed selective lignin degradation and reduced inter-fiber friction. These findings suggest that this method offers a promising, cost-effective approach for improving the structural integrity of curved wood components.

Biotechnology
DOAJ Open Access 2025
Phosphorus Cycling Dominates Microbial Regulation of Synergistic Carbon, Nitrogen, and Phosphorus Gene Dynamics During <i>Robinia pseudoacacia</i> Restoration on the Loess Plateau

Ning Peng, Yan Wang, Huifeng Wu et al.

Carbon (C), nitrogen (N), and phosphorus (P) are key soil nutrients whose synergistic interactions regulate ecosystem nutrient cycling, yet the functional gene-level coordination and driving factors of these cycles remain poorly understood. This study addresses this gap by investigating the dynamic changes in C, N, and P cycling functional genes and their microbial and environmental drivers across <i>Robinia pseudoacacia</i> plantations of different restoration stages (10, 20, 30, and 40 years) on the Loess Plateau. We analyzed soil physicochemical properties and conducted metagenomic sequencing, redundancy analysis (RDA), and Partial Least Squares Structural Equation Modeling (PLS-SEM). Results showed that P-cycling functional genes, particularly <i>pqqC</i> and <i>spoT</i>, exhibited the highest network centrality, indicating their dominant role in regulating nutrient dynamics. Compared with farmland, STC, SOC, SAP, pH, and SWC significantly changed (<i>p</i> < 0.05) with restoration age, directly shaping key microbial groups such as <i>Proteobacteria</i>, <i>Acidobacteria</i>, <i>Actinobacteria</i>, and <i>Chloroflexi</i>. These microbial shifts were strongly correlated with the synergistic changes in C, N, and P functional gene abundance (<i>p</i> < 0.01). The findings highlight the central role of phosphorus-solubilizing genes in linking C, N, and P cycles and emphasize the microbial community responses to soil environmental changes as a key driver of nutrient cycling during ecological restoration. This study provides novel insights into microbial functional gene interactions and their ecological significance in soil nutrient dynamics, offering theoretical support for improving restoration strategies on the Loess Plateau.

DOAJ Open Access 2024
Evaluation of forest loss data using fractal algorithms: case study Eastern Carpathians–Romania

Daniel Constantin Diaconu, Daniel Constantin Diaconu, Ion Andronache et al.

Logging causes the fragmentation of areas with direct implications for hydrological processes, landslides, or habitats. The assessment of this fragmentation process plays an important role in the planning of future logging, reconstruction, and protection measures for the whole ecosystem. The methodology used includes imaging techniques applying two fractal indices: the Fractal Fragmentation Index (FFI) and the Fractal Fragmentation and Disorder Index (FFDI). The results showed the annual evolution and disposition of deforested areas. Only 3% of deforestation resulted in the fragmentation and splitting of forest plots. The remaining 97% resulted in the reduction of existing compact stands without fragmentation. The method has many advantages in quantifying the spatial evolution of forests, estimating the capture of carbon emissions and establishing sustainability of bird and animal habitats. The analysis took place in the Eastern Carpathians, in Romania, in the time period of 2001–2022.

Forestry, Environmental sciences
DOAJ Open Access 2024
Floral Developmental Morphology and Biochemical Characteristics of Male Sterile Mutants of <i>Lagerstroemia indica</i>

Fuyuan Deng, Liushu Lu, Lu Li et al.

Male sterility is a common phenomenon in higher plants and often plays an important role in the selection of superior offspring. ‘Xiang Yun’ is a mutant of <i>Lagerstroemia indica</i> that does not bear fruit after flowering, and its flowering period is significantly longer than that of normal <i>L. indica</i>. To explore the timing and molecular mechanisms of sterility in ‘Xiang Yun’, this study determined the period of sterility through anatomical observation and compared the content of nutrients and the activity of antioxidative enzymes at different stages of flower development. Finally, sequence alignment and qPCR were used to analyze the differences in pollen development genes between ‘Xiang Yun’ and ‘Hong Ye’. The results showed that the anthers of ‘Xiang Yun’ dispersed pollen normally, but the pollen grains could not germinate normally. Observations with scanning electron microscopy revealed that the pollen grains were uneven in size and shriveled in shape. Further observation of anther sections found that abnormal development of the microspores began at the S2 stage, with the callose wall between microspores of ‘Xiang Yun’ being thicker than that of ‘Hong Ye’. In addition, during the flower development of ‘Xiang Yun’, the contents of soluble sugar, soluble protein, free proline, and triglycerides were deficient to varying degrees, and the activities of POD, SOD, and MDA were lower. Sequence alignment and qPCR showed that there were several mutations in <i>EFD1</i>, <i>TPD1</i>, and <i>DEX1</i> of ‘Xiang Yun’ compared with ‘Hong Ye’, and the expression levels of these genes were abnormally elevated in the later stages of development. Our results clarified the timing and phenotype of male sterility in ‘Xiang Yun’. This provides solid and valuable information for further research on the molecular mechanism of sterility in ‘Xiang Yun’ and the genetic breeding of crape myrtle.

DOAJ Open Access 2024
Comparing greenhouse and field biocrust cultivation methods in the Sonoran Desert

A. Antoninka, H. Rowe, J. Weser et al.

Abstract Developing methods to use biocrusts in restoration is becoming more important as land use and climate change impact the health and intactness of high‐stress ecosystems. Methods of cultivation to maximize the production of biocrusts for use in restoration activities are necessary because salvage opportunities are limited. Our objective for this research was to determine an optimal method for scalable biocrust cultivation. We tested two Field and one Greenhouse cultivation methods. The Field cultivation methods had a base layer of weed cloth, soil and irrigation with either (1) shade cloth immediately over the surface (Quesadilla method) or (2) with shade cloth over a 1 m tall hoophouse (Hoophouse method). The Greenhouse method had nested basins with water wicking up to the soil surface and biocrust from below, with shade cloth attached to basins. We crossed these methods with the addition of native soil or sand and with and without a base of jute using salvaged biocrusts from the Sonoran Desert. All methods led to at least doubling biocrust cover in 11 weeks. The Greenhouse method led to the highest cover of cyanobacteria and mosses, whereas the field Quesadilla method and the addition of native soil in all cultivation methods led to higher abundance of lichens. There were interactions of cultivation method and soil type, with Greenhouse cultivation and native soil promoting the highest cyanobacteria cover and chlorophyll a. We measured exopolysaccharide sheaths (EPS) in native soil and all cultivation conditions, finding no differences for tightly bound sheath fractions, but higher quantities of the loosely bound EPS in the Greenhouse. We also quantified native and non‐native plants in cultivation, finding few plants in Greenhouse cultivation, but high abundance in both Field methods, and particularly with native soil and without jute for native plants. Practical implication: Together, these results demonstrate that all three cultivation methods are successful for bulking biocrust materials for restoration, and preference should be given to the method that is the easiest and most accessible for practitioners.

Environmental sciences, Ecology
DOAJ Open Access 2024
The network regulation mechanism of the effects of heat stress on the production performance and egg quality of Jinding duck was analyzed by miRNA‒mRNA

Qingwu Xin, Li Li, Bangzhe Zhao et al.

ABSTRACT: To explore the differential regulation mechanism of heat stress on the egg production performance and egg quality of Jinding ducks, 200 Jinding ducks (360-day-old) in good health and with similar body weights and a normal appetite were selected and randomly divided into a control (normal temperature [NT]) group (20°C–25°C) and a heat stress (HS) group (32°C–36°C), with 4 replicates in each group and 25 ducks in each replicate. The pretrial period was 1 wk, and the formal trial period was 4 wk. At the end of the 4th wk, 12 duck eggs were collected from each replicate to determine egg quality. Pituitary and ovarian tissues of Jinding ducks were collected, transcriptome sequencing was performed to screen differentially expressed miRNAs and mRNAs related to high temperature and heat stress, and a competitive endogenous RNA regulatory network was constructed. The sequencing data were verified by qRT‒PCR method. The following results were obtained: (1) Compared with the NT group, the HS group had a significantly lower laying rate, total egg weight, average egg weight, total feed intake, and feed intake per duck (P < 0.01), an extremely significantly higher feed-to-egg ratio (P < 0.01), and a higher mortality rate. (2) Compared with the NT group, the HS group had an extremely significantly lower egg weight, egg yolk weight, eggshell weight, and eggshell strength (P < 0.01) and an extremely significantly lower yolk ratio and eggshell thickness (P < 0.01, P < 0.05); however, there was no significant difference in the egg shape index, Haugh unit or protein height (P > 0.05). (3) A total of 1,974 and 1,202 genes were identified in the pituitary and ovary, respectively, and there were 5 significantly differentially expressed miRNAs. The differentially expressed genes were involved in the arginine and proline metabolism pathways, ether lipid metabolism pathway, and drug metabolism–cytochrome P450 pathway, which are speculated to be related to the egg production performance of Jingding ducks under high-temperature heat stress. (4) Novel_221 may target the PRPS1 gene to participate in egg production performance; novel_168 and novel_289 may target PIGW; novel_289 may target Q3MUY2; and novel_289 and novel_208 may target PIGN or genes that may be related to high-temperature heat stress. (5) In pituitary tissue, upregulated novel_141 (center of the network) formed a regulatory network with HSPB1 and HSP30A, and downregulated novel_366 (center of the network) formed a regulatory network with the JIP1 gene. In ovarian tissue, downregulated novel_289 (center of the network) formed a regulatory network with the ZSWM7, ABI3, and K1C23 genes, novel_221 formed a regulatory network with the IGF1, BCL7B, SMC6, APOA4, and FARP2 genes, and upregulated novel_40 formed a regulatory network with the HA1FF10 gene. In summary, heat stress affects the production performance and egg quality of Jinding ducks by regulating the secretion of endocrine-related hormones and the release of neurotransmitters as well as the expression of miRNAs and mRNAs in pituitary and ovarian tissues. The miRNA‒mRNA regulatory network provides a theoretical basis for the molecular mechanism that regulates the stress response in pituitary and ovarian tissues, egg quality, and production performance under heat stress.

DOAJ Open Access 2024
Immediate and prolonged effects of snow coverage alteration on soil carbon dynamics and microbial activity: A meta-analysis

Jia Hua, Qiaoqi Sun, Petra Marschner

Snow distribution has been altered over the past decades under global warming, with a significant reduction in duration and extent of snow cover and an increase in unprecedented snowstorms across large areas in cold regions. The altered snow conditions are likely to have immediate (in winter) and carry-over or legacy (which an extended effect might continue in the following spring, summer and autumn) impacts on soil processes and functioning, but a quantification of the legacy effect of snow coverage alternation is still lacking. Furthermore, studies investigating the effect of snow cover changes on soil respiration, soil carbon pools and microbial activity are increasing, but contrasting results of different studies makes it difficult to assess the overall effect of snow cover changes and the underlying mechanisms, thus a systematic and comprehensive meta-analysis is required. In this study, we synthesized the results from 60 papers based on field snow manipulation experiments and conducted a meta-analysis to evaluate immediate and prolonged effects on eight variables related to soil carbon dynamics and microbial activity to snow coverage alternation. Results showed that snow removal had no significant effect on soil respiration, but increased dissolved organic carbon (DOC) (11.5%) and fungal abundance (32.0%). By contrast, snow addition significantly increased soil respiration (16.3%) and microbial biomass carbon (MBC) (6.6%). Snow addition had immediate and prolonged impacts on soil carbon dynamics and microbial activity lasting from winter to the following autumn, whereas an effect of snow removal on total organic carbon (TOC) and DOC was detectable only in the following spring. Snow depth, ecosystem and soil types determined the extent of the impact of snow treatments on soil respiration, DOC, MBC and microbial biomass nitrogen (MBN). Our findings provide critical insights into understanding how changes in snow coverage affect soil respiration and microbial activity. We suggest future field-based experiments to enhance our understanding the effect of climate change on soil processes and functioning in the winter and the following seasons.

DOAJ Open Access 2023
Transcriptome Analysis Reveals the Role of Phytohormones in the Distant Hybridization of Peony Embryo Abortion

Dan He, Haonan Guo, Songlin He et al.

Peonies are significant ornamental plants that are primarily propagated through distant cross-breeding to create new varieties. However, hybrid failure is a critical issue that impedes the advancement of breeding. Numerous studies have demonstrated that endogenous hormones in the seed embryo constitute a significant factor in embryo failure. Nevertheless, it is still unknown how plant hormones control the development of peony embryos at the molecular level. In this study, we characterized the endogenous hormone levels in peony seeds of hybrid-aborted, hybrid-normal, and self-crossing normal after 26 days of pollination (DAP). Our findings show that the hybrid-aborted embryos had significantly higher amounts of ABA, IAA, and GA. In addition, the ratio of GA+IAA/ABA was lower than that of the hybrid-normal seeds and higher than that of the self-crossing normal seeds. To further investigate the mechanism of hormone control on peony embryo development, we conducted a transcriptome sequencing analysis of the three seed types. Results revealed that differentially expressed genes involved in phytohormone metabolism and signal transduction significantly enriched the aborted embryos. Furthermore, we examined the expression levels of six hormones in different seeds and used the Gene Common Expression Trend analysis to analyze genes highly correlated with phytohormone in the KEGG pathway. We used protein interaction networks to explore the interactions between proteins in the hormone pathway in aborted embryos. Then we identified key genes and transcription factors (TFs) such as Abscisic acid-insensitive 5 (ABI5), Auxin Response Factor 5 (ARF5), Gibberellin Insensitive Dwarf 1 (GID1), Arabidopsis Response Regulator4 (ARR4), Jasmonate-zim-domain protein 1 (JAZ1), Brassinazole-resistant 1 (BZR1), etc., whose functions require further investigation. Our findings establish a foundation for the metabolic regulation of peony hybrid embryo abortion via networks regulating phytohormone signaling. However, further research is needed to determine the exact mechanisms by which hormones regulate peony embryo development and to explore new methods for improving the success rate of hybridization.

DOAJ Open Access 2023
First-Principles Modeling of Bottom-Up Synthesis of Carbon Quantum Dots

Danil W. Boukhvalov, Vladimir Yu. Osipov

In this work, we report the results of various scenarios related to the initial stages in the assembly of carbon quantum dots (CQDs) from citric acid (CA) or <i>o</i>-phenylenediamine (OPD). The results of the step-by-step simulations of the synthesis demonstrate that all possible scenarios of CQD assembly are different from those previously proposed. For example, in synthesizing CQDs from citric acid, each addition of a new carbon ring to the growing nanographene leads to the appearance of the carbonyl (C=O) groups on the edges and carboxyl (–COOH) groups in the interior parts of the nanographenes. Even the initial steps of CQD assembly from CA are accompanied by the formation of bushy structures from carboxyl and –CH<sub>2</sub>–COOH groups on the edges. On the other hand, in manufacturing CQDs from OPD, the formation of flat nanographenes is extremely energetically favorable. This result is in qualitative agreement with a very high yield of synthesized CQDs from OPD. However, the discussed process of nanographene formation proceeds simultaneously with the oxidation of newly formed nanographenes in a medium of superheated water accompanied by the appearance of C–OH bonds in the internal parts of newly formed <i>sp</i><sup>2</sup>- carbon species or even in their etching. For both cases, the scenario of eliminating excessive carboxyl or hydroxyl groups by forming interlayer C–C bonds between two adjacent nanographenes is estimated as possible.

Crystallography
DOAJ Open Access 2022
The Birds and the Bees: Producing Beef and Conservation Benefits on Working Grasslands

Patrick D. Keyser, David A. Buehler, John H. Fike et al.

Globally, grasslands have been heavily degraded, more so than any other biome. Grasslands of the eastern U.S. are no exception to this trend and, consequently, native biota associated with the region’s >20 million ha of agricultural grasslands are under considerable stress. For example, grassland associated breeding bird populations have declined precipitously in recent decades as have numerous species of pollinators. Although there is increasing awareness of the role grasslands can play in global carbon cycles and in providing high quality dietary proteins needed by an increasing global population, there is a lack of awareness of the alarming trends in the sustainability of the native biota of these ecosystems. Here, we present the status of this conservation challenge and offer prospective solutions through a working lands conservation approach. Such a strategy entails maintaining appropriate disturbances (i.e., grazing, fire, and their combination), improved grazing management, an increased reliance on native grasses and forbs, and improved plant diversity within pastures. Furthermore, we note some examples of opportunities to achieve these goals, offer suggestions for agricultural and conservation policy, and provide a framework for evaluating tradeoffs that are inevitably required when pursuing a multi-purpose grassland management framework.

DOAJ Open Access 2021
Empirical Approach for Modelling Tree Phenology in Mixed Forests Using Remote Sensing

Koffi Dodji Noumonvi, Gal Oblišar, Ana Žust et al.

Phenological events are good indicators of the effects of climate change, since phenological phases are sensitive to changes in environmental conditions. Although several national phenological networks monitor the phenology of different plant species, direct observations can only be conducted on individual trees, which cannot be easily extended over large and continuous areas. Remote sensing has often been applied to model phenology for large areas, focusing mostly on pure forests in which it is relatively easier to match vegetation indices with ground observations. In mixed forests, phenology modelling from remote sensing is often limited to land surface phenology, which consists of an overall phenology of all tree species present in a pixel. The potential of remote sensing for modelling the phenology of individual tree species in mixed forests remains underexplored. In this study, we applied the seasonal midpoint (SM) method with MODIS GPP to model the start of season (SOS) and the end of season (EOS) of six different tree species in Slovenian mixed forests. First, substitute locations were identified for each combination of observation station and plant species based on similar environmental conditions (aspect, slope, and altitude) and tree species of interest, and used to retrieve the remote sensing information used in the SM method after fitting the best of a Gaussian and two double logistic functions to each year of GPP time series. Then, the best thresholds were identified for SOS and EOS, and the results were validated using cross-validation. The results show clearly that the usual threshold of 0.5 is not best in most cases, especially for estimating the EOS. Despite the difficulty in modelling the phenology of different tree species in a mixed forest using remote sensing, it was possible to estimate SOS and EOS with moderate errors as low as <8 days (<i>Fagus sylvatica</i> and <i>Tilia</i> sp.) and <10 days (<i>Fagus sylvatica</i> and <i>Populus tremula</i>), respectively.

DOAJ Open Access 2021
New Corona Virus, Food Security and Identifying Policy Options

Jock R. Anderson, Latha Nagarajan, Anwar Naseem et al.

Achieving food security for all has long been a major objective in public policy around the world, and even globally as enshrined in the contemporary UN Sustainable Development Goals. The onset of the COVID-19 pandemic of 2020 creates additional challenges to food policy-makers and the paper charts some key elements of response to these challenges.

Economic history and conditions, Agriculture (General)
DOAJ Open Access 2020
The complete chloroplast genome of Tainia dunnii (Orchidaceae): genome structure and evolution

Tai-Xiang Xie, Xia Yu, Qing-Dong Zheng et al.

Tainia dunnii is a terrestrial orchid with high ornamental value. Herein, we assembled the complete chloroplast genome of Tainia dunnii by next-generation sequencing technologies. The complete chloroplast genome sequence of Tainia dunnii is 158,305 base pairs (bp) in length, including a pair of inverted repeat regions (IRs, 25,244 bp), one large single-copy region (LSC, 86,819 bp), one small single-copy region (SSC, 20,998 bp). Besides, the complete chloroplast genome contains 136 genes in total, including 88 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analysis showed that Tainia dunnii has the closest relationship with Calanthe davidii and Calanthe triplicata. Our study lay a foundation for further research of Tainia dunnii.

DOAJ Open Access 2019
Preferential Flow Modeling Using Kinematic-Dispersive Wave Model and the Role of Macrospores

M. R. Mirzaei, S. Ruy

Preferential flow is of great importance in the environment and the human health. So, rapid water transportation and consequently, pollutants and pesticides leak out and get into the groundwater, making it very difficult to measure and quantify. To quantify and describe the preferential flow, two gravity-driven models were used: 1) kinematic wave model (KW) introduced by Germann in 1985), and 2) kinematic dispersive wave (KDW) model developed by applying a second-order correction to the Germann’s model by Di Pietro et al. in 2003. So, the experimental data was obtained using the laboratory mini-rainfall-simulator over cylindrical soil samples at the laboratory. Their parameters were obtained using Solver add-ins in the Excel software. Then, the results were compared using the root-mean-square error (RMSE). The results showed that the KDW model could better predict the preferential flow (with lower RMSE). Also, the regression results showed 1) there was no significant relation between the preferential flow and the total porosity, and 2) there is a significant relation between the preferential flow and the macrospores.

Agriculture, Agriculture (General)
DOAJ Open Access 2019
Using Sentinel-2 Multispectral Images to Map the Occurrence of the Cossid Moth (<i>Coryphodema tristis</i>) in <i>Eucalyptus Nitens</i> Plantations of Mpumalanga, South Africa

Samuel Takudzwa Kumbula, Paramu Mafongoya, Kabir Yunus Peerbhay et al.

<i>Coryphodema tristis</i> is a wood-boring insect, indigenous to South Africa, that has recently been identified as an emerging pest feeding on <i>Eucalyptus nitens</i>, resulting in extensive damage and economic loss. <i>Eucalyptus</i> plantations contributes over 9% to the total exported manufactured goods of South Africa which contributes significantly to the gross domestic product. Currently, the distribution extent of the <i>Coryphodema tristis</i> is unknown and estimated to infest <i>Eucalyptus nitens</i> compartments from less than 1% to nearly 80%, which is certainly a concern for the forestry sector related to the quantity and quality of yield produced. Therefore, the study sought to model the probability of occurrence of <i>Coryphodema tristis</i> on <i>Eucalyptus nitens</i> plantations in Mpumalanga, South Africa, using data from the Sentinel-2 multispectral instrument (MSI). Traditional field surveys were carried out through mass trapping in all compartments (n = 878) of <i>Eucalyptus nitens</i> plantations. Only 371 <i>Eucalyptus nitens</i> compartments were positively identified as infested and were used to generate the <i>Coryphodema tristis</i> presence data. Presence data and spectral features from the area were analysed using the Maxent algorithm. Model performance was evaluated using the receiver operating characteristics (ROC) curve showing the area under the curve (AUC) and True Skill Statistic (TSS) while the performance of predictors was analysed with the jack-knife. Validation of results were conducted using the test data. Using only the occurrence data and Sentinel-2 bands and derived vegetation indices, the Maxent model provided successful results, exhibiting an area under the curve (AUC) of 0.890. The Photosynthetic vigour ratio, Band 5 (Red edge 1), Band 4 (Red), Green NDVI hyper, Band 3 (Green) and Band 12 (SWIR 2) were identified as the most influential predictor variables. Results of this study suggest that remotely sensed derived vegetation indices from cost-effective platforms could play a crucial role in supporting forest pest management strategies and infestation control.

DOAJ Open Access 2019
EFFECT OF PLANT DENSITIES ON GROWTH CHARACTERS, SILAGE AND GRAIN YIELD OE CORN (Zea mays L.)

Salim Younis, Abbas. M. Al-Hasans.

A Field experiment was Carried out in autumn Season of 2012 at AL- Hemidat / thaljah village 20km to the West of Mosul city and Bhashiqa / Tobzawh village 25 km east of Mosul City to Study the effect of three Plant densities(200, 300 and400 thousand plant/ha) on growth characters, silage and grain yield of two corn varieties The experiment was applied by using Randomized Compelt Blok Desing (R.C.B.D) with three replications. The results showed that there were no significant differences between the variety Bohoth 106 and Sara for all growth characteristics, silage and Grain yield at both locations except that for leaf area index and leaves percentage at Tobzawh and Number of Leaves at both locations The plant density 400 Thousand Plant/ha gave a highest silage yield for both locations, while The plant density 200 Thousand Plant/ha gave a highest grain yield at both locations The interaction between plant density and varieties was significantly affected on silage growth characters, grain yield at both locations except for Leaves percentage at / thaljah locations, plant height and number of leaves at both locations The highest silage yield was obtained from Bohoth106at 400000 plant/ha in Tobzawh (52.0tons/ha) and Thaljah (50.0tons/ha) The highest grain yield was acheaved with Sara at 200000 plant/ha in Tobzawh (3.25.tons/ha) and Thaljah (3.28tons/ha).

Agriculture
DOAJ Open Access 2018
Age-Dependent Developmental Response to Temperature: An Examination of the Rarely Tested Phenomenon in Two Species (Gypsy Moth (Lymantria dispar) and Winter Moth (Operophtera brumata))

David R. Gray

The pervading paradigm in insect phenology models is that the response to a given temperature does not vary within a life stage. The developmental rate functions that have been developed for general use, or for specific insects, have for the most part been temperature-dependent but not age-dependent, except where age is an ordinal variable designating the larval instar. Age dependence, where age is a continuous variable, is not often reported (or investigated), and is rarely included in phenology models. I provide a short review of the seldom-investigated phenomenon of age dependence in developmental response to temperature, and compare the derivation of the winter moth egg phenology model by Salis et al. to the derivation of another egg phenology model with age-dependent responses to temperature I discuss some probable reasons for the discrepancies (acknowledged by Salis et al. between modelled and observed developmental rates of the winter moth, and discuss the contribution that geographically robust phenology models can make to estimates of species distributions.

DOAJ Open Access 2014
Structural and expression analyses of three PmCBFs from Prunus mume

C. Guo, J. Q. Zhang, T. Peng et al.

C-repeat binding factor (CBF), also called the dehydration-responsive element binding factor 1 (DREB1), can be induced by low-temperature (LT), and plays an important role in abiotic stress tolerance in higher plants. In present study, two new homologous genes of CBF from Prunus mume (PmCBFb and PmCBFc) have been identified and characterized. The complete coding sequences of PmCBFb and PmCBFc were 714 and 723 bp, respectively. They encoded putative proteins of 237 and 240 amino acids. Neither of them had introns. Genome PCR sequencing showed that PmCBFb was arranged in tandem with PmCBFa (another CBF/DREB1 homolog in P. mume) within a region of nearly 4 kb. Promoter prediction analyses indicated that multiple types of cis-elements related to abiotic stress and irradiance existed in the putative promoter region of PmCBFb. LT treatment of seedlings showed that the expression of PmCBF genes were induced by 2 °C within 30 min, and their expression reached a peak after 8-12 h. In addition, PmCBFa and PmCBFb appeared more sensitive to LT than PmCBFc. However, the exact roles of PmCBF genes in plant cold tolerance need to be further investigated.

Biology (General), Plant ecology

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