Genome-wide association analysis of four yield-related traits using a maize (Zea mays L.) F1 population.

Increasing the yield of maize F1 hybrid is one of the most important target for breeders. However, as a result of the genetic complexity and extremely low heritability, it is very difficult to directly dissect the genetic basis and molecular mechanisms of yield, and reports on genetic analysis of F1 hybrid yield are rare. Taking F1 hybrid as the research object and dividing the yield into different affect factors, this approach may be the best strategy for clarifying the genetic mechanism of yield. Therefore, in this study, a maize F1 population consisting of 300 hybrids with 17,652 single nucleotide polymorphisms (SNPs) markers was used for genome-wide association study (GWAS) to filtrate candidate genes associated with the four yield-related traits, i.e., kernel row number (KRN), kernel number per row (KNPR), ear tip-barrenness (ETB), and hundred kernel weight (HKW). Combined with the results of previous studies and functional annotation information of candidate genes, a total of six candidate genes were identified as being associated with the four traits, which were involved in plant growth and development, protein synthesis response, phytohormone biosynthesis and signal transduction. Our results improve the understanding of the genetic basis of the four yield-related traits and may be provide a new strategy for the genetic basis of maize yield.

Exploring the underlying mechanisms of enteritis impact on golden pompano (Trachinotus ovatus) through multi-omics analysis.

Enteritis posed a significant health challenge to golden pompano (Trachinotus ovatus) populations. In this research, a comprehensive multi-omics strategy was implemented to elucidate the pathogenesis of enteritis by comparing both healthy and affected golden pompano. Histologically, enteritis was characterized by villi adhesion and increased clustering after inflammation. Analysis of the intestinal microbiota revealed a significant increase (P < 0.05) in the abundance of specific bacterial strains, including Photobacterium and Salinivibrio, in diseased fish compared to the healthy group. Metabolomic analysis identified 5479 altered metabolites, with significant impacts on terpenoid and polyketide metabolism, as well as lipid metabolism (P < 0.05). Additionally, the concentrations of several compounds such as calcitetrol, vitamin D2, arachidonic acid, and linoleic acid were significantly reduced in the intestines of diseased fish post-enteritis (P < 0.05), with the detection of harmful substances such as Efonidipine. In transcriptomic profiling, enteritis induced 68 upregulated and 73 downregulated genes, predominantly affecting steroid hormone receptor activity (P < 0.05). KEGG pathway enrichment analysis highlighted upregulation of SQLE and CYP51 in steroidogenesis, while the HSV-1 associated MHC1 gene exhibited significant downregulation. Integration of multi-omics results suggested a potential pathogenic mechanism: enteritis may have resulted from concurrent infection of harmful bacteria, specifically Photobacterium and Salinivibrio, along with HSV-1. Efonidipine production within the intestinal tract may have blocked certain calcium ion channels, leading to downregulation of MHC1 gene expression and reduced extracellular immune recognition. Upregulation of SQLE and CYP51 genes stimulated steroid hormone synthesis within cells, which, upon binding to G protein-coupled receptors, influenced calcium ion transport, inhibited immune activation reactions, and further reduced intracellular synthesis of anti-inflammatory substances like arachidonic acid. Ultimately, this cascade led to inflammation progression, weakened intestinal peristalsis, and villi adhesion. This study utilized multi-level omics detection to investigate the pathological symptoms of enteritis and proposed a plausible pathogenic mechanism, providing innovative insights into enteritis verification and treatment in offshore cage culture of golden pompano.

Suppression of the alpha, delta, and omicron variants of SARS-Cov-2 in Taiwan.

BACKGROUND: Taiwan was a coronavirus disease 2019 (COVID-19) outlier, with an extraordinarily long transmission-free record: 253 days without locally transmitted infections while the rest of the world battled wave after wave of infection. The appearance of the alpha variant in May 2021, closely followed by the delta variant, disrupted this transmission-free streak. However, despite low vaccination coverage (<1%), outbreaks were well-controlled. METHODS: This study analyzed the time to border closure and conducted one-sample t test to compare between Taiwan and Non-Taiwan countries prior to vaccine introduction. The study also collected case data to observe the dynamics of omicron transmission. Time-varying reproduction number,Rt, was calculated and was used to reflect infection impact at specified time points and model trends of future incidence. RESULTS: The study analyzed and compare the time to border closure in Taiwan and non-Taiwan countries. The mean times to any border closure from the first domestic case within each country were -21 and 5.98 days, respectively (P < .0001). The Taiwanese government invested in quick and effective contact tracing with a precise quarantine strategy in lieu of a strict lockdown. Residents followed recommendations based on self-discipline and unity. The self-discipline in action is evidenced in Google mobility reports. The central and local governments worked together to enact non-pharmaceutical interventions (NPIs), including universal masking, social distancing, limited unnecessary gatherings, systematic contact tracing, and enhanced quarantine measures. The people cooperated actively with pandemic-prevention regulations, including vaccination and preventive NPIs. CONCLUSIONS: This article describes four key factors underlying Taiwan's success in controlling COVID-19 transmission: quick responses; effective control measures with new technologies and rolling knowledge updates; unity and cooperation among Taiwanese government agencies, private companies and organizations, and individual citizens; and Taiwanese self-discipline.

Interregional mobility in different age groups is associated with COVID-19 transmission in the Taipei metropolitan area, Taiwan.

Before vaccines were introduced, mobility restriction was one of the primary control measures in the early stage of the coronavirus disease 2019 (COVID-19) pandemic. Because different age groups face disproportionate health risks, differences in their mobility changes affect the effectiveness of pandemic control measures. This study aimed to investigate the relationship between multiscale mobility patterns in different age groups and COVID-19 transmission before and after control measures implementation. Data on daily confirmed case numbers, anonymized mobile phone data, and 38 socioeconomic factors were used to construct negative binomial regression models of these relationships in the Taipei metropolitan area in May 2021. To avoid overfitting, the socioeconomic factor dimensions were reduced by principal component analysis. The results showed that inter-district mobility was a greater promoter of COVID-19 transmission than was intra-district mobility (coefficients: pre-alert, 0.52 and 0.43; post-alert, 0.41 and 0.36, respectively). Moreover, both the inter-district mobility of people aged 15-59 and ≥ 60 years were significantly related to the number of confirmed cases (coefficients: pre-alert, 0.82 and 1.05; post-alert, 0.48 and 0.66, respectively). The results can help agencies worldwide formulate public health responses to emerging infectious diseases.

Real-time forecasting of COVID-19 spread according to protective behavior and vaccination: autoregressive integrated moving average models.

BACKGROUND: Mathematical and statistical models are used to predict trends in epidemic spread and determine the effectiveness of control measures. Automatic regressive integrated moving average (ARIMA) models are used for time-series forecasting, but only few models of the 2019 coronavirus disease (COVID-19) pandemic have incorporated protective behaviors or vaccination, known to be effective for pandemic control. METHODS: To improve the accuracy of prediction, we applied newly developed ARIMA models with predictors (mask wearing, avoiding going out, and vaccination) to forecast weekly COVID-19 case growth rates in Canada, France, Italy, and Israel between January 2021 and March 2022. The open-source data was sourced from the YouGov survey and Our World in Data. Prediction performance was evaluated using the root mean square error (RMSE) and the corrected Akaike information criterion (AICc). RESULTS: A model with mask wearing and vaccination variables performed best for the pandemic period in which the Alpha and Delta viral variants were predominant (before November 2021). A model using only past case growth rates as autoregressive predictors performed best for the Omicron period (after December 2021). The models suggested that protective behaviors and vaccination are associated with the reduction of COVID-19 case growth rates, with booster vaccine coverage playing a particularly vital role during the Omicron period. For example, each unit increase in mask wearing and avoiding going out significantly reduced the case growth rate during the Alpha/Delta period in Canada (-0.81 and -0.54, respectively; both p < 0.05). In the Omicron period, each unit increase in the number of booster doses resulted in a significant reduction of the case growth rate in Canada (-0.03), Israel (-0.12), Italy (-0.02), and France (-0.03); all p < 0.05. CONCLUSIONS: The key findings of this study are incorporating behavior and vaccination as predictors led to accurate predictions and highlighted their significant role in controlling the pandemic. These models are easily interpretable and can be embedded in a "real-time" schedule with weekly data updates. They can support timely decision making about policies to control dynamically changing epidemics.

Docosahexaenoic acid improves cognition and hippocampal pyroptosis in rats with intrauterine growth restriction.

Background and Objective: Intrauterine growth restriction (IUGR) is defined as the failure of a fetus to reach its genetic growth potential in utero resulted by maternal, placental, fetal, and genetic factors. Previous studies have reported that IUGR is associated with a high incidence of neurological damage, although the precise causes of such damage remain unclear. We aimed to investigate whether cognitive impairment in rats with IUGR is related to pyroptosis of hippocampal neurons and determine the effect of early intervention with docosahexaenoic acid (DHA). Methods: Learning and memory function was assessed using the Morris water maze test. The morphological structure and ultrastructure of the hippocampus was examined via hematoxylin and eosin staining and electron microscopy respectively. The pyroptosis of hippocampal neuron was detected by gasdermin-D (GSDMD) immunofluorescence staining, mRNA and protein expression of nuclear localization leucine-rich-repeat protein 1 (NLRP1), caspase-1, GSDMD, and quantification of inflammatory cytokines interleukin (IL)-1ß and IL-18 in the hippocampus. Results: IUGR rats exhibited decreased learning and memory function, morphological structure and ultrastructural changes in hippocampus compared to controls. IUGR rats also exhibited increased hippocampal quantification of GSDMD immunofluorescence staining, increased mRNA and protein expression of NLRP1, caspase-1, and GSDMD, and increased quantification of IL-1ß and IL-18 in the hippocampus. Intervention with DHA attenuated these effects. Conclusion: Cognitive impairment in rats with IUGR may be related to pyroptosis of hippocampal neurons. Early intervention with DHA may attenuate cognitive impairment and reduce hippocampal pyroptosis in rats with IUGR.

Multispecies polyploidization, chromosome shuffling, and genome extraction in Zea/Tripsacum hybrids.

By hybridization and special sexual reproduction, we sequentially aggregated Zea mays, Zea perennis, and Tripsacum dactyloides in an allohexaploid, backcrossed it with maize, derived self-fertile allotetraploids of maize and Z. perennis by natural genome extraction, extended their first six selfed generations, and finally constructed amphitetraploid maize using nascent allotetraploids as a genetic bridge. Transgenerational chromosome inheritance, subgenome stability, chromosome pairings and rearrangements, and their impacts on an organism's fitness were investigated by fertility phenotyping and molecular cytogenetic techniques genomic in situ hybridization (GISH) and fluorescence in situ hybridization (FISH). Results showed that diversified sexual reproductive methods produced highly differentiated progenies (2n = 35-84) with varying proportions of subgenomic chromosomes, of which one individual (2n = 54, MMMPT) overcame self-incompatibility barriers and produced a self-fertile nascent near-allotetraploid by preferentially eliminating Tripsacum chromosomes. Nascent near-allotetraploid progenies showed persistent chromosome changes, intergenomic translocations, and rDNA variations for at least up to the first six selfed generations; however, the mean chromosome number preferably maintained at the near-tetraploid level (2n = 40) with full integrity of 45S rDNA pairs, and a trend of decreasing variations by advancing generations with an average of 25.53, 14.14, and 0.37 for maize, Z. perennis, and T. dactyloides chromosomes, respectively. The mechanisms for three genome stabilities and karyotype evolution for formatting new polyploid species were discussed.

Crystal-size effect on the kinetics of CO2 adsorption in metal organic frameworks studied by NMR.

We study the dynamics and the exchange of carbon dioxide (CO2) adsorbed in a metal organic framework (MOF) by 13C NMR for various sizes of the host crystal ranging from micrometers to millimeters. We found that the guest CO2 molecules adsorbed in [Zn2(1,4-NDC)2(dabco)]n MOF undergo exchange at a rate that depends on the size of the host crystal, revealing that the smaller the host crystals are, the faster the exchange becomes. Such a trend can be explained by the size-dependent surface-to-volume ratio.

Candidate sex-associated gene identification in Trachinotus ovatus (Carangidae) using an integrated SLAF-seq and bulked segregant analysis approach.

It is difficult to distinguish the sexes of Trachinotus ovatus based on appearance, and little data about sex-determining genes are available for this species. Here, we generated 200 F2 individuals using the parents R404 and R403. DNA samples were collected from 50 individuals of each sex and aggregated into sex-specific DNA pools. Specific-locus amplified fragment sequencing was integrated with bulked segregant analysis to detect candidate sex-associated genes. Approximately 3,153,153 high-quality single-nucleotide polymorphism (SNP) markers and 135,363 high-quality insertion-deletion (Indel) markers were generated. Six candidate regions within chromosome 14, encompassing 132 candidate genes, were identified as closely related to sex. Based on annotations, six genes (EVM0019817, EVM0004192, EVM0001445, EVM0005260, EVM0014734, and EVM0009626) were predicted to be closely associated with sex. These results present an efficient genetic mapping approach that lays a foundation for molecular sex discrimination in T. ovatus.

Effect of Female and Male Body Mass Index on Cumulative Live Birth Rates in the Freeze-all Strategy.

CONTEXT: The impact of parental overweight/obese on cumulative live birth rate in in vitro fertilization/intracytoplasmic sperm injection using a freeze-all strategy is still unknown. OBJECTIVE: To explore the effect of parental body mass index (BMI) on cumulative live birth rate (CLBR) in a freeze-all strategy over 1.5 years. METHODS: This was a retrospective study in a tertiary care academic medical center; 23 482 patients (35 289 frozen-thawed embryo transfer cycles) were divided into 4 groups according to Asian BMI classification. The main outcome measure was CLBR. RESULTS: Female overweight/obesity had a lower tendency in CLBR (groups 1-4: optimistic: 69.4%, 67.9%, 62.3%, and 65.7%; conservative: 62.9%, 61.1%, 55.4%, and 57.6%) and prolonged time (groups 1-4: 11.0, 12.2, 15.9, and 13.8 months for 60% CLBR in the optimistic method; 8.7, 9.5, 11.7, 11.0 months for 50% CLBR in the conservative method). The same trend to a lesser extent was also observed in male BMI groups. When combining parental BMI, "parental overweight/obesity" had lower CLBR and longer time for reaching CLBR >50% (optimistic: 4.5 months for 60% CLBR; conservative: 3 months for 50% CLBR), followed by "only female high BMI" (optimistic: 2.1 months for 60% CLBR; conservative: 1.7 months for 50% CLBR), while "only male high BMI" had no influence. CONCLUSION: Our results showed the importance of parental BMI, female BMI, and male BMI on the 1.5-year CLBR using a freeze-all strategy; the time to reach the CLBR (60% in optimistic, 50% in conservative) for overweight and obese patients was several months, but it is not as long as losing weight.

Variations in airborne pollen and spores in urban Guangzhou and their relationships with meteorological variables.

Airborne pollen causes various types of allergies in humans, and the extent of allergic infection is related to the presence of different types of sporo-pollen and existing meteorological conditions in a certain area. Therefore, an aeropalynological study of 72 airborne samples with a hydrofluoric acid (HF) treatment was conducted in the Haizhu district of Guangzhou, China, in 2016, to identify the temporal variations in airborne sporo-pollen and the relationship between airborne sporo-pollen concentrations and different meteorological variables in Guangzhou, China. Forty-five types of airborne pollen, seven types of airborne spores, and some undetermined sporo-pollen taxa were identified with two separate plant habitats occurring during this period (from January to December 2016): arboreal pollen (tree-based) and non-arboreal pollen (herb, shrub, aquatic, liane, etc.). Furthermore, the daily records of four key meteorological variables (temperature, precipitation, relative humidity, and wind speed) were acquired to distinguish the pollen seasons and correlated with Spearman's rho test to establish a pollen-weather data book with the seasonal variations. The two leading seasons were identified based on pollen abundance: spring and autumn. Among them, the primary dominant sporo-pollen families during the spring season were Poaceae, Pinaceae, Euphorbiaceae, Moraceae, Microlepia sp., and Polypodiaceae. Conversely, Artemisia sp., Asteraceae, Cyperaceae, Poaceae, Alnus sp., Corylus sp., Myrtaceae, and Rosaceae were the dominant pollen species during autumn. However, few pollen grains were identified in January, May-July, and December. The statistical analysis revealed that temperature had both positive and negative correlations with sporo-pollen concentrations. However, precipitation and relative humidity had a strong impact on the sporo-pollen dispersion and exhibited a negative correlation with the sporo-pollen concentrations. The wind speed had a positive but strong correlation with the sporo-pollen concentration during the study period. Some inconsistent results were found due to environmental variations, vegetation type, and climate change around the study area. This study will facilitate the identification of pollen seasons to prevent the occurrence of pollen-related allergies in the Guangzhou city area.

Reduced serum albumin as a risk factor for poor prognosis in critically ill patients receiving renal replacement therapy.

BACKGROUND: Albumin is the primary body protein, which can predict the poor prognosis of several critical diseases. However, there are a few scientific studies on the relationship between albumin and the prognosis of dialysis patients. This study aims to explore the impact of hypoalbuminemia on the prognosis of critically ill patients with acute kidney injury (AKI) receiving continuous renal replacement therapy (CRRT). METHODS: This was a secondary study. Clinical, biochemical, and 28-day and 90-day mortality rates for critical patients with AKI who received CRRT between 2009 and 2016 were searched from the database to determine the effect of hypoalbuminemia on poor outcomes by univariate, multivariate, smooth curve fitting, and subgroup analysis. RESULTS: A total of 837 participants were enrolled in this study. Multivariate Cox proportional hazard regression analysis showed that hypoalbuminemia was associated with both 28-day and 90-day mortality risks after full adjustment for confounding variables, with an adjusted hazard ratio (95% confidence interval) of 0.63 (0.50-0.80) and 0.63 (0.51-0.78), respectively for each 1 g/dL increase of albumin. Stratified analysis showed that hypoalbuminemia was not associated with poor prognosis in oliguria. CONCLUSION: Hypoalbuminemia is associated with poor prognosis in critically ill AKI patients with CRRT; therefore, measuring albumin may be helpful for predicting the prognosis. However, in those with oliguria, this conclusion is not valid.

Docosahexaenoic acid activates the Nrf2 signaling pathway to alleviate impairment of spleen cellular immunity in intrauterine growth restricted rat pups.

Intrauterine growth retardation (IUGR) impairs immune function in children. IUGR is associated with an imbalance of oxidative stress and abnormal apoptosis. Therefore, an IUGR rats model was established to determine the antioxidant capacity and apoptosis in newborn IUGR rats and explored whether these effects were regulated after Docosahexaenoic acid (DHA) supplementation to rat pups. First, eight normal-birth-weight (NBW) and eight IUGR neonatal rats (a 10% low-protein diet) were used to obtain the antioxidant capacity and apoptosis in IUGR rat pups. Then, 32 newborn rats were randomly assigned to the normal birth weight (NBW), DHA supplementation for NBW (ND), IUGR, and DHA supplementation for IUGR (ID) groups. Starting from the 7th day after birth, DHA was given to the experimental group and the same volume of distilled water was given to the control group for 21 days. (1) DHA improved the serum and spleen CD4/CD8 ratios and IL-4 and IFN-γ mRNA expression. (2) DHA decreased the level of MDA, but increased T-AOC in serum and spleen. (3) DHA increased the protein expression of Bcl-2 while decreased Bax. (4) DHA increased protein expression of the Nrf2 signaling pathway and the downstream antioxidant genes GSH-PX and CAT. DHA may alleviate the impairment of spleen cellular immunity in IUGR rat pups by inhibiting oxidative stress and apoptosis related to the activation of Nrf2 signaling pathway.

The complete mitochondrial genome of Scatophagus argus (Perciformes, Scatophagidae) from Beibu Bay and phylogenetic analysis.

The spotted scat (Scatophagus argus, Linnaeus, 1766) is a subtropical fish that is widely distributed in the coastal waters of Indo-Pacific. Here, we report the complete mitochondrial genome of S. argus. The mitogenome is 16,783 base pairs (56.0% A + T content) in length and consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and a 1007 bp D-loop region. Phylogenetic analysis showed that the relationship between S. argus and Selenotoca multifasciata was close.

The complete mitochondrial genome of yellowfin seabream, Acanthopagrus latus (Percoiformes, Sparidae) from Beibu Bay.

The yellowfin seabream, Acanthopagrus latus Houttuyn 1782, is a commercially and ecologically important species and a good model for studies of sexual differentiation. In this study, the complete mitochondrial genome of A. latus has been determined, which is 16,635 base pairs (54.3% A + T content) in length and consists of 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs, and a 948 bp D-loop region. The phylogenetic analyses showed that A. latus has a close relationship with Acanthopagrus schlegelii Bleeker 1854.

Probing dynamics of carbon dioxide in a metal-organic framework under high pressure by high-resolution solid-state NMR.

The application of high-resolution NMR analysis for CO2 adsorbed in a MOF under high pressure is reported for the first time. The results showed that CO2 adsorbed in MOF-74 had an unusually slow mobility (τ ∼ 10-8 s). CO2-CO2 interactions suppressed the mobility of CO2 under high pressure, which, in turn, would have contributed to the stability of CO2 at the adsorption sites.

Topology-Templated Synthesis of Crystalline Porous Covalent Organic Frameworks.

A strategy is presented for the synthesis of crystalline porous covalent organic frameworks via topology-templated polymerization. The template is based on imine-linked frameworks and their (001) facets seed the C=C bond formation reaction to constitute 2D sp2 carbon-conjugated frameworks. This strategy is applicable to templates with different topologies, enables designed synthesis of frameworks that cannot be prepared via direct polymerization, and creates a series of sp2 carbon frameworks with tetragonal, hexagonal, and kagome topologies. The sp2 carbon frameworks are highly luminescent even in the solid state and exhibit topology-dependent π transmission and exciton migration; these key fundamental π functions are unique to sp2 carbon-conjugated frameworks and cannot be accessible by imine-linked frameworks, amorphous analogues, and 1D conjugated polymers. These results demonstrate an unprecedented strategy for structural and functional designs of covalent organic frameworks.

Discriminative Local Sparse Representation by Robust Adaptive Dictionary Pair Learning.

In this article, we propose a structured robust adaptive dictionary pair learning (RA-DPL) framework for the discriminative sparse representation (SR) learning. To achieve powerful representation ability of the available samples, the setting of RA-DPL seamlessly integrates the robust projective DPL, locality-adaptive SRs, and discriminative coding coefficients learning into a unified learning framework. Specifically, RA-DPL improves existing projective DPL in four perspectives. First, it applies a sparse l2,1 -norm-based metric to encode the reconstruction error to deliver the robust projective dictionary pairs, and the l2,1 -norm has the potential to minimize the error. Second, it imposes the robust l2,1 -norm clearly on the analysis dictionary to ensure the sparse property of the coding coefficients rather than using the costly l0/l1 -norm. As such, the robustness of the data representation and the efficiency of the learning process are jointly considered to guarantee the efficacy of our RA-DPL. Third, RA-DPL conceives a structured reconstruction weight learning paradigm to preserve the local structures of the coding coefficients within each class clearly in an adaptive manner, which encourages to produce the locality preserving representations. Fourth, it also considers improving the discriminating ability of coding coefficients and dictionary by incorporating a discriminating function, which can ensure high intraclass compactness and interclass separation in the code space. Extensive experiments show that our RA-DPL can obtain superior performance over other state of the arts.

Allopolyploidization facilitates gene flow and speciation among corn, Zea perennis and Tripsacum dactyloides.

MAIN CONCLUSION: Tripsacum dactyloides is closely related to Zea mays since Zea perennis and the MTP tri- species hybrid have four possible reproductive modes. Eastern gamagrass (Tripsacum dactyloides L.) and tetraploid perennial teosinte (Zea perennis) are well known to possess genes conferring resistance against biotic and abiotic stresses as well as adaptation to flood and aluminum toxic soils. However, plant breeders have been hampered to utilize these and other beneficial traits for maize improvement due to sterility in their hybrids. By crossing a tetraploid maize-inbred line × T. dactyloides, a female fertile hybrid was produced that was crossed with Z. perennis to yield a tri-genomic female fertile hybrid, which was backcrossed with diploid maize to produce BC1 and BC2. The tri-genomic hybrid provided a new way to transfer genetic material from both species into maize by utilizing conventional plant breeding methods. On the basis of cytogenetic observations using multi-color genomic in situ hybridization, the progenies were classified into four groups, in which chromosomes could be scaled both up and down with ease to produce material for varying breeding and genetic purposes via apomixis or sexual reproduction. In the present study, pathways were found to recover maize and to obtain specific translocations as well as a speedy recovery of the T. dactyloides-maize addition line in a second backcross generation. However, phenotypes of the recovered maize were in most cases far from maize as a result of genetic load from T. dactyloides and Z. perennis, and could not be directly used as a maize-inbred line but could serve as an intermediate material for maize improvement. A series of hybrids was produced (having varying chromosome number, constitution, and translocations) with agronomic traits from all three parental species. The present study provides an application of overcoming the initial interspecific barriers among these species. Moreover, T. dactyloides is closely related to Z. mays L. ssp. mays since Z. perennis and the MTP tri- species hybrid have four possible reproductive modes.

Modern pollen distribution in the northeastern Indian Ocean and its significance.

In order to provide a reference for reconstructing the paleoclimate of the northeastern Indian Ocean, 36 airborne pollen samples were analyzed using methods for airborne pollen, and 26 surface water samples were analyzed using a lab method for surface water. We found that little pollen is airborne over the Indian Ocean in spring, but airborne pollen types and concentrations can help to deduce paleomonsoon strength and direction. The conclusions included the following: (1) Pollen in the sediment was transported mainly via ocean currents instead of the early summer or spring wind. (2) Airborne pollen types and concentrations are proportional to the wind speed and inversely proportional to the pollen distance transported and depend on whether the wind is from the land or from the sea. If the wind is from the land, the pollen concentration is proportional to the angle between the wind direction and the coastline. (3) The pollen concentration in the sample collected from a water depth of 30-45 m is higher than in the samples collected from a depth of 5 m. The pollen concentration and salinity are higher in the equatorial area than in the Northern Hemisphere.