Brief Summary of Minutes of Annual Meeting

Meeting was presided by Susana Goggi (IA). Minutes of Oct 2014 meeting were reviewed and approved. Discussion of next meeting ensued: will be held in Monterey, CA in conjunction with the ISSS Meeting (coordinated by K. Bradford) between 10-15 September 2017. Participants at the meeting were introduced. Presentation by Dr. Lin, National Program Leader for Plant Science from USDA-NIFA followed, where he described funding opportunities available through NIFA. Dr. Paul Johnson, Chairman, Department of Plant, Soils and Climate at Utah State University, introduced himself as the new Administrative Advisor to the Multistate Committee and shared information about his activities and programs. State reports were presented next, following the project objectives.

Objective 1 - Identifying key factors involved in the enhancement or loss of seed quality. Seed development through post-harvest losses in storage. Specific topics include seed development, desiccation tolerance, and aging in storage.

AZ: Yadegari. A new member of the Multistate Committee, provided his background and description of research on early endosperm proliferation and development in Arabidopsis and maize.  Interest in the earliest events in endosperm development; cellularization after double-fertilization; cell differentiation & specification program that leads to endosperm formation.  Has been examining gene regulation (OPAQUE 2 regulator) by exploring RNAs, building networks, transcription factors, etc.  Also using yeast 1 hybrid analysis; reverse genetic mutants in maize and laser capture micro-dissection (a very powerful tool).

CA: Bradford described his work on seed drying and the ‘Dry Chain’ – emphasizing this concept for maintaining seed quality. Described ‘low-tech’ resources such as RH indicator paper in seed containers to monitor moisture content.  This is a critical issue in humid tropics where electricity may not be reliably available.  Work includes drying beads and other dessicants. Working with Bioversity International for germplasm storage strategies.  Shared a useful motto: Make it DRY - Keep it DRY.

FL: Perez described work on various Florida wildflowers, examining the effect of mass on seed germination (Rudbeckia mollis) by using mass-separated seed lots (heavy, mid, light).  Identified potential interaction between aging stress and seed mass, but uncertain about the reason: Is this due to maturity differences? No differences from morphology. Also examining desiccation and aging stress in Gaillardia pulchella, and germination and comparative seed vigor of Eragostis elliottii (promoted by summer temps).  Described collaboration with P. Jourdan (OH) on X-ray imaging of Eragrostis seeds.

IA: Goggi shared her studies on genome fluidity in soybean, the capacity of genome to reorganize triggered by environmental stress. The changes are stable and heritable for at least a couple of years. Looked at Aconitase gene changes as a marker.

OH: Jourdan described research on seed production and quality in Phlox, as part of a program to produce seed wild sources that have appropriate quality for long-term storage.  Seed production of up to 15 Phlox species in a common garden is challenged by pollination control, harvesting of seeds that are typically forcefully dispersed, and by poor germination. Experiments are underway to explore the factors that will yield high-quality seed for long-term storage.

VA: Welbaum described his teaching of a vegetable seed production course on-line.  Also mentioned his collaboration with Bo Wang in soybean seeds with low phytate to address the challenge that low phytate lines are not inherently low in vigor, but in emergence.

Objective 2 - Eliminating seed dormancy as a constraint during seed production and germination in agronomic seed production and ecological/biomass seed establishment. Pre-mature sprouting in cereals and other species and the identification dormancy mechanisms to manipulate germination.

CA: Bradford.  Focus of research for many years has been thermodormancy in lettuce.  Examining cell wall breakdown very early in germination near the root tip, that does not occur in thermodormant lettuce (at 30c); in a lettuce PI that is not temp-sensitive, the cell wall breakdown occurs also at 30C. Ethylene appears to be involved in the difference in thermosensitivity of the 2 lines.  Also reviewed latest on DOG1 (delay of germination) involvement in dormancy; DOG1-like genes promote thermoinhibition and seem involved in dormancy; miR156 levels in lettuce are influenced by this gene. Transition from dormancy to germination is similar to juvenile/mature phase transitions in life cycle of plants (dormancy to germination; embryo to seedling; juvenile to adult; adult to flowering; embryogenesis to seed development; all involve micro RNAs

KY: Geneve.  Examining seed dormancy in Sycios, involving anatomical study of seed development.  Shared informative movie of a water gap opening and closing. Combinational dormancy (physical and physiological - perisperm-associated).  Another study looked at integumental tapetum in Echinacea tennesiensis where the tapetum is ‘sequestering the developing embryo-filial tissue’ from the maternal tissue.

SD: Gu. His lab focuses on the understanding of seed dormancy from natural variation to qtl, genes, and regulatory networks in rice. A system biology approach toward understanding gene regulatory networks of seed dormancy.  Seed dormancy trait regulates the timing of germination; have detected 10 qtls for seed dormancy in rice.   Noted that seed dormancy is not an independent trait in evolution; it is related to pericarp color, flowering time, plant height, hull color, awn length (co-location of qtl’s for these traits).  Also identified association (correlation) between plant height and dormancy (shorter plants, more dormant seeds) - related to GA issues? GA reduction delays seed ABA accumulation and development. The seed dormancy-plant height association is underlain by 2 pleiotropic genes involved in GA biosynthesis. Hybrid rice seed germinates only to 80%; same gene that affects height also increases dormancy.

LA: ‘Cohn’s Last Gasp’ – Soliloquy.  Indicated he is retiring in 2016. Shared an historical perspective on seed dormancy. How do non-hormonal chemicals break dormancy of weed seeds? How to rationalize the structural diversity of dormancy-breaking chemicals? Why do recalcitrant seeds die when dried? Are we measuring responses to drying or dying? Spartina alterniflora has recalcitrant seeds; cold tolerant, flooding tolerant, dormant when shed.  Related species - S. pectinata is orthodox. Looked at proteins that differ between orthodox and recalcitrant Spartina: dehydrogenase, LEA, chaperonins, ubiquitin & autophagy related proteins, SOD, peroxiredoxins, glutathione peroxidase; 38 proteins different between recalcitrant and orthodox; there are some cis elements in common in 35 of these proteins.  Finally, presented a brief history of his lab’s work (since the 1980’s).  Left us with the question: When recalcitrant seeds die, are dying because of drying or during rehydration?

Objective 3 - Enhancing seed vigor and germination in agronomic and other species for improved stand establishment. The emphasis of this objective is on post-harvest technologies.

CA: Bradford.  Shared work on population-based threshold models that describe seed respiration and germination rates.  Using Q2 respiratory instrument to generate population-based oxygen depletion curves - respiratory time courses. There is excellent correlation between respiration and germination.  Identified subpopulations within seed lots that behave differently, e.g. in respiration, aging – that could not be detected by germination tests.  The system can be used as a very precise vigor test and check for seed lot quality (especially with mixed lots that have populations of different maturity, aging). Can be used to potentially identify the deterioration before it occurs (long lag phase before sudden drop in viability in long-term storage; can be used to predict decline based on models). Respiration rates can substitute for germination rates for all sorts of physiological parameters. A replacement system for germination.

FL: Perez.  Research for objective 3 focuses on enhancing seed germination in agronomic and native species for improved stand establishment: Harperocallis flava (narrow endemic in FL).  Arare plant with no knowledge of seed biology and desire to increase the limited population; embryos undifferentiated/undeveloped at mature seed release; unique germination pattern described by Geneve involving a haustorial cotyledon and other interesting modified structures; also reported on students and publications (for the group)

IA: Goggi & Manjit Misra. Working on phages that could be used in seed coatings to control bacterial diseases; also an international collaboration in Ghana - USAID for project on technology transfer.  This collaboration includes Goggi’s work on biosafety & on the story that biotechnology is safe (e.g. does not cause sterility in males).  The project also involves seed testing laboratory design and training, PhD training.

NY: Taylor. His work focuses on seed technology; manages NY seed testing laboratory.  Studying the effect of gelatin capsule treatment on cucumber plant growth and stress tolerance.  Also looking at plant biostimulants: microbial inoculants; humid and fluvic acid, protein hydrolysate and amino acids; seaweed extracts.  In general, most biostimulants applied to foliage; not much with seeds.  An observation: multiple seeds inside of a gelatin capsule, resulting plants more vigorous.  Trying multiple empty capsules near seeds - are they acting as fertilizers? There seems to be promotion of growth by capsules beyond nitrogen fertilizer. Also testing coating of broccoli seeds with soy flour as a plant-derived coating material. Collaborative work with other W3168 members, Brian Nault (entomologist) and Eric Nelson (plant pathologist) from Cornell who are interested in biostimulants to control insects and pests. Other work involves looking at fluorescent dyes to follow movement of systemic compounds in seed coating/treatments.

VA: Welbaum.  Described nanochitin seed treatment of pepper - induces an SAR-like response in seedlings.  Organic seed treatments: tea tree oil seems to suppress fungal growth on soybean seeds.  Also looking at peanut germination in gusseted thermogradient table to assess temperatures; boron fertilization reputed to be beneficial for peanut seed quality (during production) - no evidence so far that Boron is beneficial.

TX: Leskovar.  Enhancing seed germination in agronomic and native species for improved stand establishment.  Uvalde region very important for Winter vegetable production; depend on Edwards aquifer - high quality water, but level drops dramatically in drought years.  A major area is use of PGRs for enhanced vegetable transplant quality; e.g. ABA or 1-MCP-ethylene inhibitor application enhances drought stress tolerance (physiological conditioning), arrest shoot growth (MCP).  Also looking at stand establishment in artichoke - use GA to induce bolting when plants grown in summer; grafting is under consideration.  Examined low nitrogen fertilizer to condition the plants for transplant (better root systems); also looking at effect of ethylene on root development.  Noted that seed quality and vigor extremely important in leafy vegetable hydroponic production systems.

W3168 Sub-Committee Reports:

New officers : Greg Welbaum, chair (will chair meeting in 2018).  Camille Steber nominated for secretary (must confirm with her)

Mitch McGrath, USDA-MSU - will chair W3168’s 2017 meeting in Monterey

2018 meeting - possibility of VA Tech (hosted by Welbaum) or perhaps Chicago area with PanAmerican Seed.

One of W3168’s goals is to host an international seed meeting in 2017.  The meeting will be the 12^th  International Seed Science Society Workshop - Monterey, CA, Sept 10-15, 2017  coordinated by Dr. Kent Bradford and the Multistate Committee. Discussion followed about the meeting expenses, establishment of scientific committee, strategy and leaders for grants (NSF, Gu; USDA, Perez); potential sponsorship by Seed Companies.  Also an initial discussion of the scientific program was held, to be followed-up by e-mail exchanges and phone conferences between W3168 members.  Components of the program include pre-conference tours, plenary and concurrent sessions, posters, special presentations.   Additional discussion centered on site visits in the Salinas area.  The organizing committee will continue discussions throughout 2016.

Objective 1

CA-Bradford: Methods have been developed to utilize single-seed respiratory data obtained through the ASTEC Q2 instrument in population-based threshold models. This quantitative analysis of the respiratory characteristics of seed populations enables labor-efficient monitoring of seed quality and new insights into seed germination, vigor and aging.

Development of a new zeolite-based desiccant for seed drying enables seed drying without heating with major implications for maintaining seed quality, particularly in humid climates. It is scalable from the individual farmer to large companies. When applied to food grains and commodities, desiccant-based drying has the potential to greatly reduce postharvest loss and improve food safety by preventing accumulation of fungal toxins (e.g., aflatoxin) in storage.

FL-Perez: We evaluated the germination of mass separated Rudbeckia mollis seeds exposed to favorable temperatures, heat stress and aging stress. We also evaluated the tolerance of Gaillardia pulchella seeds to aging stress and extreme levels of desiccation. We collected data on: 1) the relationship between relative humidity and seed water content (i.e. water sorption isotherms); 2) the germination ability of seeds following equilibration to a range of relative humidity (i.e. desiccation tolerance); and 3) the germination ability of seeds following exposure to conditions of high relative humidity and temperature (aging stress). Germination of R. mollis seeds under simulated seasonal temperatures and constant temperatures was greater or equal to 90% at temperatures up to 29/19C and constant 30C, but decreased similarly across all mass classes at higher temperatures until seeds became thermoinhibited at 37C. Final germination decreased up to 14 and 40% across all mass classes with increasing duration of aging stress. Seeds of G. pulchella displayed initial water potential of about -53 MPa. Germination remained above about 75% following exposure to increasing levels of desiccation and aging stress. We learned that seed mass variation does not reduce germination uniformity in R. mollis following exposure to favorable conditions. However, extended accelerated aging periods are needed to elucidate if higher levels of stress will promote differential germination responses among mass classes. This is important in understanding how mass based germination responses may shift as plants adapt to a warming climate. We also realized that seeds of G. pulchella are exceptionally resilient to desiccation and aging stress. These results suggest that germplasm conservation of G. pulchella seeds under genebank conditions is feasible. Additionally, G. pulchella seeds should be tolerant of variable and stressful establishment conditions.

OH-Jourdan: Understanding the seed quality parameters that may influence long-term storage for Phlox has involved studies of phenology, pollination strategy, fruit and seed development, harvesting, conditioning and germination. We have observed that seed quality in Phlox seed is primarily determined by the endosperm itself as the majority of seeds that failed to germinate due to fungal growth during stratification had viable embryos that could germinate when isolated from the seed. We have developed protocols for TZ testing of Phlox that permit us to establish baseline values for seed viability prior to seed lot germination tests, which are challenging due to the high level of fungal development, even after fungicide treatment. We have also developed efficient methods to isolate embryos from mature seed to determine germination potential and response to external signals, such as GA.

OR-Nongaki: Abscisic acid (ABA) has negative effects on seed germination and causes slow stand establishment with low vigor. On the other hand, lack of ABA could cause wilty plants and seed maturation problems. It is necessary to control ABA-regulated events in seeds and plants for agricultural production. To this end, it is essential to understand the mechanisms of ABA-regulated biochemical and molecular events in seeds and plants. We took advantage of NCED (nine-cis-epoxycarotenoid dioxygenase; ABA biosynthesis enzyme) increase in seeds in one of our experimental systems, to identify more factors associated with ABA regulation in seeds. We performed RNA sequencing under normal vs. high ABA conditions. We identified DELAY OF GERMINAITON1-LIKE 4 (DOGL4) as one of the ABA up-regulated gene, which we are currently characterizing. In addition to many other coding genes, we also identified ABA-induced long non-coding RNAs, which we named ABAIRs. We are currently characterizing function of ABAIR1.

Objective 2

CA-Bradford: We have demonstrated that seed dormancy and plant flowering times are connected through the action of the DELAY OF GERMINATION 1 (DOG1) gene. This gene is known to be involved in the establishment of seed dormancy and its loss during after-ripening. We have demonstrated in both lettuce (LACTUCA SATIVA) and ARABIDOPSIS THALIANA that DOG1 function is involved in regulating both of these life cycle transitions by influencing the production of microRNAs miR156 and miR172. This work has significant implications for how plants interact with environment to time major life cycle transitions (e.g., germination and flowering) to their reproductive advantage.

We have genetically identified a new quantitative trait locus (QTL) in lettuce (LACTUCA SATIVA) that can partially alleviate thermoinhibition, which prevents seed germination following imbibition at warm temperatures. We previously identified a different QTL on chromosome 6 from a wild (LACTUCA SERRIOLA) accession (UC96US23) which was subsequently fine-mapped and identified to be due to differential expression of LsNCED4, a gene in the abscisic acid biosynthetic pathway. Now, using a different germplasm source (PI251246, LACTUCA SATIVA), we identified a QTL on chromosome 9 that confers germination tolerance at high temperature and tentatively identified the causal gene as ETHYLENE RESPONSE FACTOR 1 (ERF1) (Yoong et al., 2016). This provides an additional source of germplasm for this beneficial trait and provides further insight into the role of ethylene in promoting germination under stressful conditions. Dissemination of this germplasm will enable breeders to increase the high temperature limits for lettuce seed germination and improve crop stand establishment in hot seasons and locations.

The effects of environmental conditions (particularly temperature) during seed development were characterized through analysis of genetic x environmental interactions influencing seed quality and other reproductive traits in the PI251246 x Salinas mapping population. A distinct QTL was identified as contributing to the influence of temperature during seed development on subsequent seed performance.

KY-Geneve & B. Downie: The involvement of enclosing maternal tissue layers in physiological seed dormancy were investigated in three species with different morphologies. The major seed covering tissue layer(s) reported to be involved in physiological seed dormancy maintenance are usually the endosperm and endosperm cap. However, maternal tissue layers also play a role in maintaining physiological dormancy. The current species and tissue types under study include the perisperm envelope in bur cucumber (Sycios), the integumentary endothelium in coneflower (Echinacea), and the pericarp/endothelium in gamagrass (Tripsicum). In bur cucumber removal of the perisperm envelope results in 100% germination. In gamagrass, the germination unit is a caryopsis enclosed in dried floral tissue (cupule). Removal of the caryopsis from the cupule does not change seed germination percentage, but germination in seeds where the other maternal tissue layers are punctured increases germination by greater than 50 percent. In coneflower, there is an integumentary tapetum (endothelium) that lies just below the seed coat and surrounds the embryo. Piercing or removal of the endothelial layer increases germination by 35 to 45% depending on the species. It is plausible that in these three representative species, the described maternally-derived tissue layers present a physical barrier or limit solute movement across the enclosing envelope to participate in control of physiological dormancy.

MI-McGrath: Sugar beet growers plant seeds in sub-optimal conditions of moisture and temperature. Previous work focused on moisture stress during germination for which two genetic processes were uncovered that have had good impact in improving the 60% of planted seeds that, on average, survive to produce a harvested sugar beet in Michigan. The current work expands on this to include temperature extremes likely encountered by sugar beet seed at planting in either cool climates such as Michigan or warm climates such as California. In both cases, a marked reduction in overall gene expression was observed, and the suites of genes expressed were not overlapping in their predicted biochemical functions.

OR-Nonogaki: We had developed dormancy-inducing technology by using a chemically inducible gene expression (Plant Gene Switch System: PGSS) in collaboration with Prof. Roger Beachy, University of California, Davis. In addition, we developed a new system of spontaneous dormancy, which does not require chemical induction. Both systems successfully induced seed dormancy, which can be applied to preventing precocious germination, such as preharvest sprouting (PHS) in cereal crops. However, these approaches require a counteracting technology to recover germination and rescue viable seeds. For this purpose, another chemically inducible gene expression system was developed using a nitrate-inducible promoter. Briefly, nitrate itself has dormancy releasing effects through upregulation of ABA deactivation genes. If RNA interference against ABA biosynthesis genes are combined by this approach, dual effects of seed germination promotion is expected. This will be a perfect answer to the objective "Eliminating seed dormancy as a constraint during seed production and germination".

SD-Gu: Research activities on seed dormancy in rice include: 1) purifying isogenic lines and transgenic lines for cloned seed dormancy (SD) genes SD1-2, SD7-2, SD12a, SD12b and Sd12c and evaluating their dormancy degrees by standard germination testing; 2) sequencing alleles of these genes from a collection of wild, weedy and cultivated rice and genotyping the collected accessions to characterize evolutionary mechanisms of the dormancy genes; and 3) conducing a series of genomic and molecular biology experiments from the RNA to the protein and hormone levels to characterize developmental mechanisms of seed dormancy by the cloned genes.

Outputs and short-term outcomes mainly include: 1) completed a multi-year project to clone and characterization of the SD1-2 QTL; 2) completed cloning and validation of candidate genes for the qSD12 QTL, and initiated a transcriptomic analysis for the QTL underlying genes; and 3) advanced projects to fine-map and clone of the qSD7-2 and qSD1o QTL.

Objective 3

CA-Bradford: We have continued to expand on the application of population-based threshold models for the analysis of seed quality and behavior (e.g., dormancy, respiration, viability). These models enable the quantification of the physiological status of seed lots and the variation in quality among seeds in the population. They are being increasingly applied in seed ecology and evolution as well. I contributed to a recent review in Trends in Ecology and Evolution (Donohue et al., 2015) in which applications of this basic model were demonstrated for diverse life cycle applications. We also contributed to a paper published in Ecology (Huang et al., 2015) in which these models were applied to quantify the contribution of seed traits to species diversity and demographics in the Arizona desert. We have also now extended the model to enable it to separate and identify distinct subpopulations within a blended seed lot, for example. These models have become the standard method of quantifying certain aspects of seed performance and we continue to extend the range of seed characteristics and life cycle stages to which they can be applied.

FL-Perez: We studied the germination response of two accessions of Elliot's Lovegrass, harvested in different years, to simulated seasonal temperatures and 25C. Seed vigor testing via accelerated aging methods was also conducted. We collected data pertaining to final germination, germination rate and germination uniformity. Final germination was greater than 80% for seeds exposed to spring, summer or fall temperatures. However, seeds exposed to summer temperatures displayed the most rapid (75%in 3 days) and complete germination (89%) in a significantly differnt temporal germination pattern. Germination was reduced by 7% for seeds collected in 2012 and exposed to aging stress. However, germination was reduced in the 2013 lot by 14-27%. We learned that seeds of Elliot's Lovegrass are released from thermal germination constraints in multiple seasons, but actual field emergence may vary based on differences in vigor between seed lots.

NY-Taylor: Seed coat permeability was examined using a model that tested the effects of soaking tomato (Solanum lycopersicon) seeds in combination with carbon-based nanomaterials (CBNMs) and ultrasonic irradiation (US). Penetration of seed coats to the embryo by CBNMs, as well as CBNMs effects on seed germination and seedling growth, was examined. Two CBNMs, C60(OH)20 (fullerol) and multiwalled nanotubes (MWNTs), were applied at 50mg/L, and treatment exposure ranged from0 to 60 minutes. Bright field, fluorescence, and electron microscopy and micro-Raman spectroscopy provided corroborating evidence that neither CBNM was able to penetrate the seed coat.The restriction of nanomaterial (NM) uptake was attributed to the semipermeable layer located at the innermost layer of the seed coat adjacent to the endosperm. Seed treatments using US at 30 or 60 minutes in the presence of MWNTs physically disrupted the seed coat; however, the integrity of the semipermeable layer was not impaired. The germination percentage and seedling length and weight were enhanced in the presence of MWNTs but were not altered by C60(OH)20. The combined exposure of seeds to NMs and US provided insight into the nanoparticle-seed interaction and may serve as a delivery system for enhancing seed germination and early seedling growth.

Seed agglomeration is a coating technology with the purpose to sow multiple seeds of the same seed lot, or multiple seeds of different seed lots, varieties or species. The objective of this study was to develop agglomeration technology by producing single agglomerates or pellets using lettuce and tomato as model vegetable crop seeds. Physical properties of dry and wet pellets were measured and seedling emergence assessed. Pellets were formed by a molding technique with a mixture of filler, binder, and seeds. Diatomaceous earth (DE) was used as the filler, and two binders were tested: polyvinyl alcohol (PVA) and SOL034, a commercial, organic binder. Each binder solution was mixed with DE, and seeds were added during the agglomeration process. Oval and cylindrical pellets were molded with known compression forces. Pellet strength increased as PVA binder concentration increased from 8% to 16% and pellet strength was greater for pellets produced with 3 kg than 1 kg compression. The percent seedling emergence and speed of emergence were not affected by a compression force of 1 kg and 3 kg for lettuce and tomato, respectively compared to the non-pelleted control. Pellets containing three tomato seeds produced plants with greater leaf area, fresh and dry weight than plants grown from single seeds, 26 days after being sown in the greenhouse.

Biostimulants are chemicals that stimulate plant growth and increase plant protection from biotic and abiotic stress. Protein hydrolysates are classified as one type of biostimulant, and have been shown to have a positive effect on plant growth. The effect of gelatin, a kind of animal protein hydrolysate was evaluated on plant growth. Enhanced plant growth was measured in the aboveground portions of plants with the application of gelatin capsules applied at time of sowing adjacent to seeds. Crops tested (cucumber, tomato, broccoli, corn, arugula, pepper) showed increased plant growth as measured by leaf area, fresh and dry weight. The magnitude of plant growth enhancement was crop specific, and cucumber was used as the model crop for all further studies. Plants treated with gelatin capsules exhibited increased nitrogen content, and increased salinity tolerance compared to the nontreated control. Different types of hydrolyzed collagen, including granulated gelatin, gelatin hydrolysate, and amino acid mixtures containing amino acids present in gelatin were compared and revealed that granulated gelatin treatment had the greatest plant growth compared with other treatments. Plants were treated with two gelatin capsules and equivalent amount of nitrogen in the form of urea revealed that increased plant growth from the application of gelatin capsule was not solely due to the nitrogen. RNA-seq results provided some insights on the mechanisms of the growth promotion from the gelatin capsule treatments. Genes were upregulated from the gelatin treatment involved in nitrogen transport including ammonium transporters and amino acid transporters, and genes involved in abiotic stress tolerance such as WRKY transcription factors. Genes involved in detoxification such as Glutathione S-transferase exhibited a high positive correlation with increase leaf area and nitrogen content in plants treated with gelatin capsule.

Atoum, Y., M. J. Afridi, J. M. McGrath, and L. E. Hanson. (2016) On developing and enhancing plant-level disease rating systems in real fields. J. Pattern Recognition 53: 287-299.

Donohue, K., Burghardt, L.T., Runcie, D., Bradford, K.J., and Schmitt, J. (2015) Applying developmental threshold models to evolutionary ecology. Trends in Ecology and Evolution 30: 66-77.

Genna, N.G., Kane, M.E., and Perez, H.E. (2015) Simultaneous assessment of germination and infection dose-responses in fungicide-treated seeds with non- and semiparameteric statistical methods. Seed Science and Technology. 43: 168-186.

Gu, Lei, · Zhang, Yumin, · Zhang, Mingshuai, · Li, Tao · Dirk, Lynnette M. A., ·Downie, Bruce, · Zhao, Tianyong (2016) ZmGOLS2, a target of transcription factor ZmDREB2A, offers similar protection against abiotic stress as ZmDREB2A. Plant Mol. Biol. 90:157–170. DOI 10.1007/s11103-015-0403-1

Han, Qinghui, Li, Tao, Zhang, Lifeng, Yan, Jun, Dirk, Lynnette M.A., Downie, Bruce, Zhao, Tianyong (2014) Functional Analysis of the 5’-Regulatory Region of the Maize ALKALINE ALPHA-GALACTOSIDASE1 Gene. Plant Mol. Biol. Rep. DOI 10.1007/s11105-014-0840-z

Hanson, L. E., Goodwill, T. R., and McGrath, J. M. (2015) Beta PIs from the USDA-ARS NPGS evaluated for resistance to Cercospora beticola, 2014. Plant Disease Management Reports. 9:FC001.

Huang Z, Liu S, Bradford KJ, Huxman TE, Venable DL (2015) The contribution of germination functional traits to population dynamics of a desert plant community. Ecology 97: 250-261.

Huo, H., Bradford, K.J. (2015) Molecular and hormonal regulation of thermoinhibition of seed germination. In J.V. Anderson (ed.), Advances in Plant Dormancy, Springer, NY, pp. 3-33.

McDonald, M.R., Vander Kooi K. and A. G. Taylor (2015) Evaluation of insecticides for control of onion maggot in yellow cooking onions, 2014. Muck Vegetable Cultivar Trial & Research Report 2014. Dept. of Plant Agriculture, Muck Crops Research Station, King, ON. Report No. 64. p. 68-69.

McDonald, M.R., Vander Kooi K. and A. G. Taylor (2015) Evaluation of insecticides for control of onion maggot in yellow cooking onions, 2014. Pest Management Research Reports (on-line). http://phytopath.ca/wp-content/uploads/2015/05/Compiled-PMRR-Final-May-11.pdf

McGrath, J. M., Hanson, L. E., and Panella, L. W. (2015) Registration of SR98 sugarbeet germplasm with high levels of resistance to Rhizoctonia seedling damping-off and crown and root rot diseases. J. Plant Registrations 9: 227-231

McGrath, J.M., Townsend, B. J. (2015) Sugar Beet, Energy Beet, and Industrial Beet. Pp. 81-99. in "Handbook of Plant Breeding. Volume 9. Industrial Crops: Breeding for Bioenergy and Bioproducts." Editors: V.M.V. Cruz and D.A. Dierig.

Nonogaki M, Sekine T, Nonogaki H. (2015) Chemically inducible gene expression in seeds before testa rupture. Seed Science Research 25, 345-352.

Nonogaki M, NonogakiH. (2016) Seed development: Germination. In B. Thomas, B. Murray, D. Murphy eds, Encyclopedia of Applied Plant Sciences, Second Edition Biology, Elsevier, Oxford, in press

Pan, L., Zhu, Q., Lu, R., and McGrath, J.M. (2015). Determination of sucrose content in sugar beet by portable visible and near-infrared spectroscopy. Food Chemistry167: 264-271.

Pan, L., Lu, R., Zhu, Q., McGrath, J. M., and Tu, K. (2015) Measurement of moisture, soluble solids, and sucrose content and mechanical properties in sugar beet using portable visible and near-infrared spectroscopy. Postharvest Biology and Technology. 102:42-50.

Panella, L., Hanson L. E., McGrath, J. M., Fenwick, A. L., Stevanato, P., Frese, L., and Lewellen, R. T. (2015) Registration of ‘FC305’ multigerm sugarbeet germplasm selected from a cross to a crop wild relative. J. Plant Registrations 9: 115-120. 2015.

Pérez, H.E. (2014) Do habitat and geographic distribution influence decreased seed viability in remnant populations of a keystone bunchgrass? Ecological Restoration 32: 295-305.

Ratnikova, T. R., R. Podila, A. M. Rao, and A. G. Taylor (2015) Tomato seed coat permeability to selected carbon nanomaterials and enhancement of germination and seedling growth, The Scientific World Journal, vol. 2015, Article ID 419215, 9 pages doi:10.1155/2015/419215

Sikhao, P., A. G. Taylor, E. T. Marino, C. M. Catranis and B. Siri (2015) Development of seed agglomeration technology using lettuce and tomato as model vegetable crop seeds. Scientia Horticulturae: 184, 85-92.

Wilson, H. T. (2015) Gelatin, a biostimulant seed treatment and its impact on plant growth, abiotic stress, and gene regulation. PhD thesis, Cornell University

Wilson, H. T., K. Xu, and A. G. Taylor (2015) Transcriptome analysis of gelatin seed treatment as a biostimulant of cucumber plant growth, The Scientific World Journal, vol. 2015, Article ID 391234, 14 pages. doi:10.1155/2015/391234

Yoong F-Y, O'Brien LK, Truco MJ, Huo H, Sideman R, Hayes R, Michelmore RW, Bradford KJ. (2016) Genetic variation for thermotolerance in lettuce seed germination is associated with temperature-sensitive regulation of ETHYLENE RESPONSE FACTOR1 (ERF1). Plant Physiology 170: 472-488.