Gregory Environmental

Little Meadows, PA, United States

Gregory Environmental

Little Meadows, PA, United States

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Han Y.,CAS Wuhan Botanical Garden | Vimolmangkang S.,Gregory Environmental | Soria-Guerra R.E.,Gregory Environmental | Soria-Guerra R.E.,Autonomous University of San Luis Potosi | Korban S.S.,Gregory Environmental
Journal of Experimental Botany | Year: 2012

Three genes encoding anthocyanidin reductase (ANR) in apple (Malus×domestica Borkh.), designated MdANR1, MdANR2a, and MdANR2b, have been cloned and characterized. MdANR1 shows 91% identity in coding DNA sequences with MdANR2a and MdANR2b, while MdANR2a and MdANR2b are allelic and share 99% nucleotide sequence identity in the coding region. MdANR1 and MdANR2 genes are located on linkage groups 10 and 5, respectively. Expression levels of both MdANR1 and MdANR2 genes are generally higher in yellow-skinned cv. Golden Delicious than in red-skinned cv. Red Delicious. Transcript accumulation of MdANR1 and MdANR2 genes in fruits gradually decreased throughout fruit development. Ectopic expression of apple MdANR genes in tobacco positively and negatively regulates the biosynthesis of proanthocyanidins (PAs) and anthocyanin, respectively, resulting in white, pale pink-coloured, and white/red variegated flowers. The accumulation of anthocyanin is significantly reduced in all tobacco transgenic flowers, while catechin and epicatechin contents in transgenic flowers are significantly higher than those in flowers of wild-type plants. The inhibition of anthocyanin synthesis in tobacco transgenic flowers overexpressing MdANR genes is probably attributed to down-regulation of CHALCONE ISOMERASE (CHI) and DIHYDROFLAVONOL-4-REDUCTASE (DFR) genes involved in the anthocyanin pathway. Interestingly, several transgenic lines show no detectable transcripts of the gene encoding leucoanthocyanidin reductase (LAR) in flowers, but accumulate higher levels of catechin in flowers of transgenic plants than those of wild-type plants. This finding suggests that the ANR gene may be capable of generating catechin via an alternative route, although this mechanism is yet to be further elucidated. © 2012 The Author.


Vimolmangkang S.,Gregory Environmental | Vimolmangkang S.,Chulalongkorn University | Zheng D.,Gregory Environmental | Han Y.,CAS Wuhan Botanical Garden | And 6 more authors.
Gene | Year: 2014

Although the mechanism of light regulation of color pigmentation of apple fruit is not fully understood, it has been shown that light can regulate expression of genes in the anthocyanin biosynthesis pathway by inducing transcription factors (TFs). Moreover, expression of genes encoding enzymes involved in this pathway may be coordinately regulated by multiple TFs. In this study, fruits on trees of apple cv. Red Delicious were covered with paper bags during early stages of fruit development and then removed prior to maturation to analyze the transcriptome in the exocarp of apple fruit. Comparisons of gene expression profiles of fruit covered with paper bags (dark-grown treatment) and those subjected to 14. h light treatment, following removal of paper bags, were investigated using an apple microarray of 40,000 sequences. Expression profiles were investigated over three time points, at one week intervals, during fruit development. Overall, 736 genes with expression values greater than two-fold were found to be modulated by light treatment. Light-induced products were classified into 19 categories with highest scores in primary metabolism (17%) and transcription (12%). Based on the Arabidopsis gene ontology annotation, 18 genes were identified as TFs. To further confirm expression patterns of flavonoid-related genes, these were subjected to quantitative RT-PCR (qRT-PCR) using fruit of red-skinned apple cv. Red Delicious and yellow-skinned apple cv. Golden Delicious. Of these, two genes showed higher levels of expression in 'Red Delicious' than in 'Golden Delicious', and were likely involved in the regulation of fruit red color pigmentation. © 2013 Elsevier B.V.


Vyakaranam K.V.,Rutgers University | Ashokan B.K.,Rutgers University | Kokini J.L.,Rutgers University | Kokini J.L.,Gregory Environmental
Journal of Food Engineering | Year: 2012

The effect of paddle element geometry, specifically a systematic change in stagger angle, on the velocity distribution of a Newtonian corn syrup was evaluated in the mixing region of a 2″ Readco continuous processor using 3D FEM simulations. Local velocities and regions of backflow were compared for three configurations of the paddle elements in the mixing region consisting of nine pairs of paddle elements with the central three being in a neutral (FLAT), staggered 45° forward (45F) or staggered 45° reverse (45R) configuration. The total material flow rate through the mixer was independent of the paddle element stagger but increased with screw speed when the mixer was operated with the barrel fully filled. The stagger angle variation caused only local disturbances in axial flow. The overall magnitudes of velocity were highest for the FLAT configuration followed by 45F and 45R. The local X and Y velocity components in the region of stagger showed no significant variation with paddle element stagger while the Z velocity component varied significantly in this region. Increased forward flow was seen for the 45F configuration while significant local backflow was seen for the 45R configuration at all positions of the paddle element rotation. The FLAT configuration had greater levels of pressure in the intermeshing region, suggesting a squeeze flow while there were not significant variations in pressure for the 45F and 45R configurations, suggesting a predominantly conveying/leakage flow in the axial direction. Variation in local flows is critical to good mixing. © 2011 Elsevier Ltd. All rights reserved.


Wu J.,Nanjing Agricultural University | Zhao G.,Nanjing Agricultural University | Yang Y.-N.,Nanjing Agricultural University | Le W.-Q.,Hebei Academy of Agriculture and Forestry science | And 4 more authors.
Tree Genetics and Genomes | Year: 2013

Fruit skin color is an important parameter of outer quality and plays an important role in attracting customers. In many plants, it is the result of coordinative regulation of anthocyanin pathway genes. In our study, the differential expression of cDNA library in a pair of pear mutant with red and green color was investigated to find candidate genes which might regulate the anthocyanin biosynthesis and control the coloration of pear. We constructed a cDNA library using the cDNA-amplified fragment length polymorphism approach to analyze the transcriptional differences between the original cultivar "Early red Doyenne du Comice" with high anthocyanin content in the peel and its green color mutant with comparatively low anthocyanin content. Altogether, 47 transcript-derived fragments, putatively involved in anthocyanin biosynthesis, primary metabolism, stress, and defense responses, were identified. The relationships of differentially expressed genes and coloration were investigated by quantitative real-time PCR with fruit skin samples at different developmental stages. A gene putatively involved in anthocyanin biosynthesis was found and named as PyMADS18. Its sequence is similar to genes reported in the literature as regulators of anthocyanin biosynthesis. The expression results indicate that PyMADS18 is likely to be involved in anthocyanin accumulation and regulation of anthocyanin synthesis in early fruit development of pear. © 2012 Springer-Verlag.


Vimolmangkang S.,Gregory Environmental | Vimolmangkang S.,Chulalongkorn University | Han Y.,CAS Wuhan Botanical Garden | Wei G.,CAS Wuhan Botanical Garden | And 2 more authors.
BMC Plant Biology | Year: 2013

Background: Red coloration of fruit is an important trait in apple, and it is mainly attributed to the accumulation of anthocyanins, a class of plant flavonoid metabolites. Anthocyanin biosynthesis is genetically determined by structural and regulatory genes. Plant tissue pigmentation patterns are mainly controlled by expression profiles of regulatory genes. Among these regulatory genes are MYB transcription factors (TFs), wherein the class of two-repeats (R2R3) is deemed the largest, and these are associated with the anthocyanin biosynthesis pathway. Although three MdMYB genes, almost identical in nucleotide sequences, have been identified in apple, it is likely that there are other R2R3 MYB TFs that are present in the apple genome that are also involved in the regulation of coloration of red color pigmentation of the skin of apple fruits.Results: In this study, a novel R2R3 MYB gene has been isolated and characterized in apple. This MYB gene is closely related to the Arabidopsis thaliana AtMYB3, and has been designated as MdMYB3. This TF belongs to the subgroup 4 R2R3 family of plant MYB transcription factors. This apple MdMYB3 gene is mapped onto linkage group 15 of the integrated apple genetic map. Transcripts of MdMYB3 are detected in all analyzed tissues including leaves, flowers, and fruits. However, transcripts of MdMYB3 are higher in excocarp of red-skinned apple cultivars than that in yellowish-green skinned apple cultivars. When this gene is ectopically expressed in Nicotiana tabacum cv. Petite Havana SR1, flowers of transgenic tobacco lines carrying MdMYB3 have exhibited increased pigmentation and accumulate higher levels of anthocyanins and flavonols than wild-type flowers. Overexpression of MdMYB3 has resulted in transcriptional activation of several flavonoid pathway genes, including CHS, CHI, UFGT, and FLS. Moreover, peduncles of flowers and styles of pistils of transgenic plants overexpressing MdMYB3 are longer than those of wild-type plants, thus suggesting that this TF is involved in regulation of flower development.Conclusions: This study has identified a novel MYB transcription factor in the apple genome. This TF, designated as MdMYB3, is involved in transcriptional activation of several flavonoid pathway genes. Moreover, this TF not only regulates the accumulation of anthocyanin in the skin of apple fruits, but it is also involved in the regulation of flower development, particularly that of pistil development. © 2013 Vimolmangkang et al.; licensee BioMed Central Ltd.


Zhang Q.,CAS Wuhan Botanical Garden | Zhang Q.,University of Chinese Academy of Sciences | Li J.,CAS Wuhan Botanical Garden | Zhao Y.,Hebei Academy of Agricultural and Forestry science | And 2 more authors.
Plant Molecular Biology Reporter | Year: 2012

China, one of the primary centers of genetic diversity for the genus Malus, is very rich in wild apple germplasm. In this study, genetic diversity in 29 Malus accessions, including 12 accessions from 7 Chinese Malus species, 4 Chinese landraces, and 13 introduced apple cultivars, was assessed using a set of 19 single-locus simple sequence repeat (SSR) markers distributed across all 17 linkage groups of the apple genome. The number of alleles detected at each locus ranged from 2 to 11, with an average of 5.3 per SSR marker. In some accessions, 16 unique alleles were identified. Ten out of these 16 unique alleles (62.5%) were detected exclusively in wild species, indicating that these Chinese wild apple species have considerable genetic diversity and can be used in breeding programs to increase the genetic diversity of apple cultivars. Using 19 SSRs, an unweighted pair-group method with arithmetic average cluster analysis was conducted, and the resulting dendrogram revealed that all cultivars, except for Ef{cyrillic}peMeBckoe, were clustered together in the same group. The Russian cultivar Ef{cyrillic}peMeBckoe was closely related to the Chinese crabapple Baihaitang (M. prunifolia), with a high similarity coefficient value of 0.94. Of the two M. sieversii accessions used, one accession showed a close relationship to apple cultivars, while the other accession was closely related to wild apple species, suggesting the presence of a wider genetic diversity in Chinese M. sieversii species. The influence of SSR marker selection on genetic diversity analysis in this Malus collection was also discussed. © 2011 Springer-Verlag.


Han Y.,CAS Wuhan Botanical Garden | Zheng D.,Gregory Environmental | Vimolmangkang S.,Gregory Environmental | Khan M.A.,Gregory Environmental | And 2 more authors.
Journal of Experimental Botany | Year: 2011

A total of 355 simple sequence repeat (SSR) markers were developed, based on expressed sequence tag (EST) and bacterial artificial chromosome (BAC)-end sequence databases, and successfully used to construct an SSR-based genetic linkage map of the apple. The consensus linkage map spanned 1143cM, with an average density of 2.5cM per marker. Newly developed SSR markers along with 279 SSR markers previously published by the HiDRAS project were further used to integrate physical and genetic maps of the apple using a PCR-based BAC library screening approach. A total of 470 contigs were unambiguously anchored onto all 17 linkage groups of the apple genome, and 158 contigs contained two or more molecular markers. The genetically mapped contigs spanned ∼421Mb in cumulative physical length, representing 60.0% of the genome. The sizes of anchored contigs ranged from 97kb to 4.0Mb, with an average of 995kb. The average physical length of anchored contigs on each linkage group was ∼24.8Mb, ranging from 17.0Mb to 37.73Mb. Using BAC DNA as templates, PCR screening of the BAC library amplified fragments of highly homologous sequences from homoeologous chromosomes. Upon integrating physical and genetic maps of the apple, the presence of not only homoeologous chromosome pairs, but also of multiple locus markers mapped to adjacent sites on the same chromosome was detected. These findings demonstrated the presence of both genome-wide and segmental duplications in the apple genome and provided further insights into the complex polyploid ancestral origin of the apple. © 2011 The Author.


Anderson E.,Gregory Environmental | Arundale R.,Urbana University | Maughan M.,Urbana University | Oladeinde A.,Urbana University | And 2 more authors.
Biofuels | Year: 2011

Miscanthus × giganteus is a highly productive, sterile, rhizomatous, C4 perennial grass that should be considered as a feedstock for bioenergy production. Here, we review the current state of research and the future of M. × giganteus biomass production. Since the 1980s, the grass has been studied and used in Europe to produce heat and electricity via combustion. Since 2005, the US government has encouraged research using herbaceous feedstocks for conversion to ethanol for use as transportation fuel. M. × giganteus is being widely studied in the USA because of its potential to produce large quantities of biomass. This review examines the taxonomy and genetics, growth and development, physiology and agronomy, and modeled and potential 'real-world' yields of M. × giganteus in Europe and the USA. In addition, the invasiveness and the future perspective of M. × giganteus utility and research in the USA are also considered. © 2011 Future Science Ltd.


Samtani J.B.,Gregory Environmental | Masiunas J.B.,Gregory Environmental | Appleby J.E.,Gregory Environmental
HortScience | Year: 2010

Previous research by the authors found simulated acetochlor (with atrazine) and s-metolachlor drift to white oak at the leaf unfolding stage caused loss of interveinal tissues (leaf tatters). Reports of leaf tatters in the landscape and nursery settings are more common on white oak (Quercus alba L.) than on northern red oak (Quercus rubra L.). Our objectives were to determine if white and northern red oak differed in susceptibility to chloroacetanilide herbicides, if injury varied between chloroacetanilide herbicides, and if adding atrazine increased leaf injury. Two-year-old seedlings at the leaf unfolding stage were treated with acetochlor, s-metolachlor, and dimethenamid-P alone or combined with atrazine at 1%, 10%, and 25% of the standard field use rate. Within 6 days, all chloroacetanilides at 10% and 25% field use rates, alone or combined with atrazine, caused leaf tatter injury in both species. Acetochlor, s-metolachlor, and dimethenamid-P caused a similar type of leaf injury. Atrazine did not cause loss of leaf tissues or increase injury from chloroacetanilides. At 1% field use rate, only acetochlor, acetochlor + atrazine, and dimethenamid-P caused leaf injury to northern red oaks. The white oaks were not injured by all of the chloroacetanilide treatments at 1% field use rate. The northern red oaks were slightly more susceptible to chloroacetanilides compared with the white oaks. A second study found acetochlor only injured northern red oak when applied at the leaf unfolding stage and only at 25% of field use rate. Acetochlor at 1% field use rate did not injure red oak. Research is needed to explain the greater frequency of leaf tatters on white oaks than on northern red oaks in the landscape and to develop strategies to avoid tree injury.


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