PECAN CULTIVAR SELECTION, ROOTSTOCK EVALUATION, AND POST-HARVEST PHYSIOLOGY

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1009343
• Project Start Date: Feb 29, 2016
• Project End Date: Feb 5, 2019
• Program Code: [(N/A)]- (N/A)

Project Director
Graham, C.

Recipient Organization
LOUISIANA STATE UNIVERSITY
202 HIMES HALL
BATON ROUGE,LA 70803-0100

Performing Department
Red River Station

Non Technical Summary
This project will benefit the pecan industry directly through the development of more productive and,profitable cultivars and rootstocks. Consumers of pecans willindirectly benefit byenhanced production and market stability. By developing pest resistant cultivars, this research will reduce production costs and environmental pollution, benefiting both producers and the general public.Beyondhigher production,capacity and consumers are demanding cultivars with more consistent quality, better health benefits, and uniqueness as new products. The development of varieties with more consistent quality would help expand the consumption of pecans. The development of cultivars with accentuated health benefits or other unique traits would expand the pecan market and increase profits.One of the most important decisions facing growers when establishing new orchards is the choice of rootstock. The selection of scion varieties are well known for their impact on long-term productivity and profitability of an orchard, however, rootstock selection is often neglected. Rootstocks influences water and nutrient absorption, assimilate storage, anchorage, and biochemical synthesis. The use of improved or better adapted rootstocks can potentially increase tree production and nut quality. They also mayallow orchard expansion into marginal sites not possible with current rootstocks.Awareness among consumers about the relationship between diet and health is a sign for food industries to pay more attention to the possibilities of health protecting properties in new product development. Currently, there is a growing interest in phytochemicals formally considered to be nonnutritive, but now have demonstrated they perform a physiological role in the human body. Limited research has been conducted to identify or develop pecan cultivars that maximize the health benefits of the nut. There is a potential of developing new varieties that have a higher level of phytochemicals for fresh consumption, but also to develop new food products based on the phytochemical properties of pecan.With the enactment of the Food Safety Modernization Act (FSMA) produce safety rule, producers who grow crops that are consumed raw will be required to take preventive control measures to reduce the risk of foodborne diseases (US-FDA 2014). FDA recommends a treatment process must achieve a 5 log reduction of microbial populations to be regarded as a kill step. Food products processed with a kill step will insure food safety in the final products. Thus, identifying a kill step in pecan processing is vital for reducing the food safety risk associated with pecans grown in orchards that are also used for pasture. The goal of this project is to develop research based processing technology to reduce food safety risk associated with pecan and increase economic competitiveness of Louisiana pecan processors. This project is important because critical knowledge gaps exist regarding the fate of pathogens and effect on quality of pecans after hot water or steam treatments.

Animal Health Component

70%

Research Effort Categories

Basic

10%

Applied

70%

Developmental

20%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
202	1211	1080	10%
203	1211	1010	30%
701	1211	1010	30%
712	1211	1100	30%

Knowledge Area
203 - Plant Biological Efficiency and Abiotic Stresses Affecting Plants; 712 - Protect Food from Contamination by Pathogenic Microorganisms, Parasites, and Naturally Occurring Toxins; 202 - Plant Genetic Resources; 701 - Nutrient Composition of Food;

Subject Of Investigation
1211 - Pecan;

Field Of Science
1010 - Nutrition and metabolism; 1100 - Bacteriology; 1080 - Genetics;

Keywords

pecan

carya

cultivars

rootstock

post-harvest quality

salmonella

food safety

Goals / Objectives
One of the focuses of this project is the development of improved pecan scion and rootstock varieties through modern pecan evaluation and selectionapproaches. New cultivars are needed that will provide higher yields and that will resistant to serious insect pests such as the yellow aphid complex and to diseases such as pecan scab.Work under this project benefits pecan producers as a result of higher yields and lower chemical costs associated with insect and disease control, which will increase profit margins. The consumer benefits as a result of increased pecan production efficiency resulting in more stable pecan prices, and from a cleaner environment due to diminished chemical applications to control pests. There is a potential of developing new varieties that have a higher level of phytochemicals for fresh consumption, but also to develop new food products based on the phytochemical properties of pecan. Additionally, a goal of this project is to develop research based processing technology to reduce food safety risk associated with pecan and increase economic competitiveness of Louisiana pecan processors. This project is important because critical knowledge gaps exist regarding the fate of pathogens and effect on quality of pecans after hot water or steam treatments. Specific objectives are as follows:A.Pecan Cultivar Evaluation andSelection 1. Develop pecan cultivars with characteristics superior to existingcultivars available to Louisiana growers. 2. Evaluate native seedlings and develop germplasm for future breeding and genetic studies. 3. Develop and evaluate rootstocks for potential use in commercial pecanproduction.B. Post-Harvest Physiology 1. Evaluate pecan cultivars andcontrolled-crossgermplasm for phytochemical concentrations.2. Identify the time and temperature parameters for hot water treatment during pecan processing that can be regarded as a kill step. Determine the effect of treatments on carbohydrate and tocopherol profiles and sensory qualities.

Project Methods
The following selection scheme is used in the pecan program. In Phase I, the traditional crossing technique is used to produce hybrid seed each year. All seed produced by these hand crosses are planted directly in the greenhouse, and seedlings are measured for growth parameters during the first year. The seedlings are transplanted to the orchard for Phase II testing. The seedlings are grown at close spacing, under conditions that encourage natural scab infection. Only resistant seedlings are selected and enter Phase III testing. During Phase II, post-harvest nut quality is evaluated annually and used in the selection process. Phase III pecan selections are propagated on a common rootstock and these trees are used for evaluation of desirable horticultural characteristics such as yield, tree size increase, precocity, nut quality, disease and insect resistance, desirable leaf and tree structure, etc. External clones selected from other pecan programs may be included in this Phase for comparison and evaluation under Louisiana growing conditions. During Phase IV, elite clones from Phase III are tested in replicated trials across the Pecan Belt, mainly for environmental adaptation. Clones that perform well in Phase IV tests will be released as new cultivars. The selection program is targeted at originating new, early maturing, precocious, high yielding, regular bearing, disease and insect resistant, high quality pecan cultivars.Currently used pecan rootstocks will be evaluated on the effect irrigation water salinity has on vegetative growth parameters and ion accumulation. One year old pecan rootstocks will be exposed to salinity treatments for a full growing season. At the end of the experiment, seedlings will be destructively harvested and dry weights measured on roots and shoots. Elemental analyses will be performed on dry tissue, ground to pass through a 20-mesh screen, using the Association of Analytical Chemist (AOAC) methodology (Cunniff, 1995) at the Louisiana State University Plant Analysis Lab. Nitric acid microwave digestion will be performed using a CEM microwave (MDS 2000 model). A Leem Lab inductively coupled plasma emission (ICP) spectrophotometer will be used to obtain measurements for macro- and micronutrient concentrations.Initial work on the influence of rootstock on nut quality will deal with an established pecan orchard at the Pecan Research Station. An orchard planted in 2006 contains 'Pawnee' pecan variety grafted onto 4 rootstocks (Creek, Elliott, Moore, and Stuart) with 30 replications. Mature pecans will be harvested, cracked, and shelled. Nuts per pound and percent kernel will be calculated. The kernels will be stored at -80°C prior to analysis. The effect of hot water and steam treatments during pecan processing on phytonutrients, such as phenolics, fatty acids, and tocopherols will be assessed following different time and temperature parameters. In-shell pecans that are commonly grown in Louisiana will be selected based on factors such as high average tonnage produced annually and difference in shell thickness, shell-out percentage (percent of in-shell nut consisting of nutmeat), size, and shape of nuts. Pecans will be stored at 4oC until used in the experiments. Only undamaged in-shell pecans will be used in the experiments. Conditioned nuts will be submerged in hot water at a range from 75 to 95oC for several time periods. For stream treatments, the conditioned nuts will be exposed to steam for several time periods. After heat treatment, samples will be transferred to stomacher bag and immersed into ice to bring down the temperature as soon as possible. The peroxide value (AOAC Method 965.33) and the free fatty acid level (AOAC method 940.28) will be determined on treated kernels. Sensory evaluation will be performed immediately after the hot water treatments and after 3 weeks of storage (that mimic commercial conditions) to determine if consumers can detect overall differences between untreated vs. treated pecans using the descriptive analysis as described by Guerrero et al. (1996).Lipid Analysis (AOAC Official Method 948.22). Pecan full fat flours will be weighed in cellulose thimbles and extracted with petroleum ether in a soxlet apparatus for 16 hours. The extracted thimbles will be dried for 24 hours at ambient temperature in a fume hood to remove residual petroleum ether. The samples weights will be used to calculate the lipid content of the pecan kernels. Phenolic Analysis. Total soluble phenolics of the pecan kernels will be determined by the Folin-Ciacalteu procedure (Singleton et al., 1999) using gallic acid as a standard. Results are expressed as milligrams of gallic acid equivalent per 100 g of kernel on a fresh weight basis. Antioxidant Analysis. The ferric reducing/antioxidant power (FRAP) assay will be used to determine the total antioxidant power of the pecan kernels (Benzie and Strain, 1999). The FRAP assay uses antioxidants as reductants in a redox-linked colorimetric method, employing an easily reduced oxidant present in stoichiometric excess. Ascorbic acid is used as a standard and converted to μmol FRAP value/100 g kernel weight. Soluble Carbohydrate analyisis. The pecan kernels will be frozen in liquid nitrogen and stored at -70? C. Soluble carbohydrate extraction will be done according to the method of Boersig and Nemg (1985) as modified by Miller and Langhans (1989). Soluble sugars are extracted from 50 mg of tissue using methanol:chloroform:water (12:5:3 ratio). Mannitol (1.0 mg) is added as an internal standard at the beginning of the first extraction. The methanol:water phase will be applied to a polyethylene column containing polyvinylpolypyrrolidone (PVPP) and cation and anion exchange resins (1 ml Dowex 50-W, 100-200 mesh layered on 1 ml of Amberlite IRA-45, 16-50 mesh layered on 1 ml acid washed PVPP (Loomis and Battaile, 1966)). Soluble carbohydrates are eluted from the column with 3 ml methanol:water (1:1 ratio by volume) and evaporated to dryness under reduced pressure using a rotary evaporator. The residue is redissolved in 2 ml HPLC-grade water and filtered through a Gelman 0.45-mm membrane filter. Soluble sugars will be analyzed using a Waters HPLC system (Waters Associates, Milford, MA, USA). Sugars are separated on a Shodex SC1011 column (300 X 7.8 mm i.d., sulfonated styrene divinylbenzene resins, calcium form; Millipore Corp., Cary, NC, USA) and peak areas determined using a differential refractometer detector. Determination of specific sugars are based on comparison of retention times to those of authentic D-sugars. Operating conditions are as follows: column temperature, 80°C; mobile phase, water; flow rate, 0.8 ml/min.The starch content in the residue following soluble carbohydrate extraction is determined using the glucose oxidase method (Sigma Tech. Bull. 510) after digestion with amyloglucosidase. Four ml of 0.1 M Na-acetate buffer is added to each sample and boiled for 20 minutes to gelatinize the starch (Haissig and Dickson, 1979). One ml of amyloglucosidase (Sigma product number A7255) solution (50 units/ml in 0.1 M, pH 4.2) is added to each sample after it has cooled to room temperature. The samples are incubated in a covered water bath at 53°C for 48 hr with occasional agitation.The amount of glucose in the samples is determined by adding 5.0 ml of ice-cold enzyme solution (25 units glucose oxidase, 5 units peroxidase, and 0.2 mg o-dianisidine in 0.1 M Na-phosphate buffer, pH 7.2) to a 100 ml aliquot of digested sample. The mixture is incubated for 30 min at 35°C in a circulating water bath. One ml of 2.2 N HCl is added to each sample after incubation to stop the reaction and stabilize the colored product. Absorbance will be measured at 450 nm using a Spectronic Genesys 2 spectrophotometer (Spectronic Instruments, Rochester, NY, USA). Glucose standards are used to determine the actual concentrations of glucose.

Progress 02/29/16 to 02/05/19

Outputs
Target Audience:Target audiences included both commercial and residential pecan growers in Louisiana. Additionally, commercial growers across the Southeastern pecan belt were targeted. Pecan evaluations and acquired information from the applied pecan breeding program are developed for the growers, nursery industry, and homeowners in Louisiana and surrounding states with areas of similar environments. The scientific information developed in the areas of pecan genetics, pecan husbandry, and the health benefits of pecan nuts is aimed at the scientific community. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Varietal selection and management of fruits and nuts recommended for Northwest Louisianawas discussed at the Louisiana Nursery in Keithville, LA. Training workshops for Good Agricultural Practices (GAPs) was held at Hammond and Alexandria, LA. The history and mechanics of pecan grafting was discussed at the Ark-La-Miss Tri-State Conference in Monroe, LA. A group panel discussion on the varietal, physiological and climate effects on pecan quality was held at the Texas Pecan Growers Association Conference and Tradeshow at Frisco, TX. Produce Safety Alliance (PSA) Grower Training & Optional Good Agricultural Practices (GAPs) Food Safety Plan Writing Workshops will be held in Lafayette and Oak Grove, LA. Articles published in PecanSouth discussed how environmental and nutritional stresses have an additive effect on pecan tree production, the effect of inadequate chilling on pecan growth and production, insect and disease management during the summer months, and the effect that rainy, cloudy weather during nut filling has on nut kernel quality. How have the results been disseminated to communities of interest?Interviews on pecan orchards, production, disease, and marketing were conducted with LSU AgCenter Communications and the Red River Radio. Outreach materials have been provided to health professionals, Extension Agents, and the general public. Information has been shared utilizing lectures and laboratory classes in the Louisiana Master Gardener Program. One-on-one audience contact has been by telephone, fax, station visits, on-farm visits, and grower meetings. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The breeding program is targeted at originating new, early maturing, precocious, high yielding, regular bearing, disease and insect resistant, high quality pecan cultivars. Several controlled-cross seedlings were selected from the breeding orchard at the Pecan Research/Extension Station for propagation and evaluation in replicated trials to determine if they are worthy to be released as new pecan cultivars. The transcriptome of a developing pecan nut was characterized to identify the gene expression occurring during the process of nut development and to highlight those genes involved in fatty acid metabolism and those that commonly act as food allergens. Pecan samples were collected over multiple time points during the embryo development including the water, gel, dough, and mature nut stages. Up-regulated fatty acid metabolism genes identified included acyl-[ACP] desaturase and omega-6 desaturase genes involved in oleic and linoleic acid metabolism. Notably, some of the up-regulated acyl-[ACP] desaturase and omega-6 desaturase genes identified have expression patterns similar to the allergen genes based upon gene expression clustering and qPCR analysis. These findings suggest the possibility of coordinated accumulation of lipids and allergens during pecan nut embryogenesis. The effect of hot water pre-treatment of in-shell pecans on physicochemical properties, consumer acceptance and purchase intent of dehulled and roasted kernels was evaluated. In-shell pecans were first subjected to hot water at 70, 80 and 90ºC for 8.6, 6.6 and 4.6 min, respectively and kernels were later dry roasted at 160?C for 10 min. Hot water treatment, alone, and subsequent roasting had minimal effect on pecans' physicochemical properties. Consumers liked (P<0.05) color and aroma of treated pecans. No effect (P>0.05) of pre-treatment was observed on acceptability of other sensory attributes. Hot water treatment showed promise as a post-harvest microbial intervention strategy without affecting the eating quality and consumer acceptability.

Publications

• Type: Other Status: Accepted Year Published: 2018 Citation: Kharel, K., Yemmireddy, V.K., Graham, C.J., Prinyawiwatkul, W., Adhikari, A. 2018. Effect of hot water treatment of in-shell pecans on physico-chemical properties and consumer acceptability of roasted pecan kernels. LWT - Food Science and Technology Journal: (accepted). Kharel, K., Yemmireddy, V.K., Graham, C.J., Prinyawiwatkul, W., Adhikari, A. 2018. Hot water treatment as a kill-step to inactivate E. coli O157:H7, Salmonella spp., Listeria monocytogenes and Enterococcus faecium on in-shell pecans. LWT - Food Science and Technology Journal: 97:555-560. Yemmireddy, V. K., Cason, C., Graham, C. J., Adhikari, A. 2018. Antimicrobial activity of pecan shell extracts against various foodborne bacterial pathogens. International Association for Food Protection Conference, Salt Lake City, Utah, July 8  11, 2018. (abstr.). Graham, C. 2018. GAP Certification helps specialty crop growers address food safety. Noble News & Views 36 (12):7-8. Rohla, C. and Graham, C. 2018. U.S. pecan growers face devastating storms, tariff trouble. Noble Research Institute Agripulse. Oct. 31, 2018; www.noble.org/campaigns/pecans. Graham, C.J. 2018. Low input doesnt mean no input. Pecan South 51(9):6-8. Adhikari, A., Kharel, K., Graham, C. Pecan Safety: Hot water conditioning to mitigate microbial hazards. LSU AgCenter Publication 3642, 2 pages. Graham, C.J. 2018. As the world turns, the marketing landscape shifts. Pecan South 51(6):6-8. Graham, C.J. 2018. If you want to have nuts, protect your leaves. Pecan South 51(3):20-21, 23, 25-26. Graham, C.J. 2018. Caring For Freeze-Damaged Citrus Trees. Horticulture Hints, Spring Edition pp. 12-13. Graham, C.J. 2018. A new year, a new crop to care for. Pecan South 50(12):40-44. Burrack, H., Brannon, P., Oliver, J., .Cline, B., Melanson, R., Graham, C., Hale, F., Sial, A., Czarnota, M., Jennings, K., Lockwood, D., Smith, P., Fontenot, K., Gauthier, N. 2018. Southeast Regional Blueberry Integrated Management Guide. The Southern Region Small Fruit Consortium. 54 pages. Oliver, J., Schnabel, G., Melanson, R., Burrack, H., Sial, A., Bessin, R., Hale, F., Pfeiffer, D., Mitchem, W., Jennings, K., Lockwood, D., Fernandez, G., Brannen, P., Smith, P., Sikora, E., Fontenot, K., Graham, C., Stafne, E. 2018. Southeast Regional Caneberry Integrated Management Guide. The Southern Region Small Fruit Consortium. 53 pages.

Progress 10/01/16 to 09/30/17

Outputs
Target Audience:Target audiences included both commercial and residential pecan growers in Louisiana. Additionally, commercial growers across the Southeastern pecan belt were targeted. Pecan evaluations and acquired information from the applied pecan breeding program are developed for the growers, nursery industry, and homeowners in Louisiana and surrounding states with areas of similar environments. The scientific information developed in the areas of pecan genetics, pecan husbandry, and the health benefits of pecan nuts is aimed at the scientific community. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Varietal selection and management of fruits and nuts recommended for northwest LA was discussed at the Louisiana Nursery in Keithville, LA. Training workshops for Good Agricultural Practices (GAPs) was held at Hammond and Alexandria, LA. The history and mechanics of pecan grafting was discussed at the Ark-La-Miss Tri-State Conference in Monroe, LA. A group panel discussion on the varietal, physiological and climate effects on pecan quality was held at the Texas Pecan Growers Association Conference and Tradeshow at Frisco, TX. Produce Safety Alliance (PSA) Grower Training & Optional Good Agricultural Practices (GAPs) Food Safety Plan Writing Workshops will be held in Lafayette and Oak Grove, LA. Articles published in PecanSouth discussed how environmental and nutritional stresses have an additive effect on pecan tree production, the effect of inadequate chilling on pecan growth and production, insect and disease management during the summer months, and the effect that rainy, cloudy weather during nut filling has on nut kernel quality. How have the results been disseminated to communities of interest?Interviews on pecan orchards, production, disease, and marketing were conducted with LSU AgCenter Communications and the Red River Radio. Outreach materials have been provided to health professionals, Extension Agents, and the general public. Information has been shared utilizing lectures and laboratory classes in the Lousiana Master Gardener Program. One-on-one audience contact has been by telephone, fax, station visits, on-farm visits, and grower meetings. What do you plan to do during the next reporting period to accomplish the goals?Continue care of the Pecan Breeding orchard, which consists of seedlings originating from controlled crosses at the Pecan Research Station. Nut samples are evaluated annually to aid in selection of superior seedlings to be propagated for further testing in a commercial setting. Develop and evaluate rootstocks for potential use in commercial pecan production. Continue training and cultural management of the joint Pecan Demonstration orchard established in 2005. Yields and nut quality are evaluated on an annual basis. Harvested nuts will also be used in food safety evaluations. Continuing working to develop science based processing technology to reduce food safety risk of Louisiana produced pecans. Identify theeffect hot water treatment during pecan processing on pecan kernel quality and storage duration. Continue collaborating with USDA scientists to characterize expression of allergens in pecan kernels.

Impacts
What was accomplished under these goals? The breeding program is targeted at originating new, early maturing, precocious, high yielding, regular bearing, disease and insect resistant, high quality pecan cultivars. Several controlled-cross seedlings were selected from the breeding orchard at the Pecan Research/Extension Station for propagation and evaluation in replicated trials to determine if they are worthy to be released as new pecan cultivars. Pecan samples of different varieties were used to develop a post-harvest hot water treatment as a kill step to destroy foodborne pathogens. Hot water treatment for 8.6, 6.6, and 4.6 minutes at 70, 80, and 90 degrees Celcius will reduce food pathogens by 5 log CFU/g. However, more research is necessary to determine the effects on long term kernel quality. The transcriptome of a developing pecan nut was characterized to identify the gene expression occurring during the process of nut development and to highlight those genes involved in fatty acid metabolism and those that commonly act as food allergens. Pecan samples were collected over multiple time points during the embryo development including the water, gel, dough, and mature nut stages. Up-regulated fatty acid metabolism genes identified included acyl-[ACP] desaturase and omega-6 desaturase genes involved in oleic and linoleic acid metabolism. Notably, some of the up-regulated acyl-[ACP] desaturase and omega-6 desaturase genes identified have expression patterns similar to the allergen genes based upon gene expression clustering and qPCR analysis. These findings suggest the possibility of coordinated accumulation of lipids and allergens during pecan nut embryogenesis.

Publications

• Type: Other Status: Published Year Published: 2017 Citation: Malekian, Fatemeh, Adhikari, Achyut, Graham, Charles J., Fontenot, Kathryn, Lewis Ivey, Melanie. "Transporte de productos agr�colas frescos: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3442-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Fontenot, Kathryn, Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Lewis Ivey, Melanie. "Manipulaci�n poscosecha de frutas y verduras las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3443-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Lewis Ivey, Melanie, Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Fontenot, Kathryn. "Agua de poscosecha las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3444-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Fontenot, Kathryn, Lewis Ivey, Melanie. "Evaluaciones de precosecha de los riesgos para la inocuidad de los alimentos". 2017, Publication No. 3445-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Fontenot, Kathryn, Lewis Ivey, Melanie. "Mantenimiento de registros en la granja: si no se anot�, no sucedi�". 2017, Publication No. 3446-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Lewis Ivey, Melanie, Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Fontenot, Kathryn. "Desinfecci�n de semillas de plantas hort�colas: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3447-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Lewis Ivey, Melanie, Adhikari, Achyut, Graham, Charles J., Fontenot, Kathryn, Malekian, Fatemeh. "Desinfecci�n del agua de lavado con cloro: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3448-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Fontenot, Kathryn, Lewis Ivey, Melanie. "Salud e higiene de los trabajadores: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3449-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Malekian, Fatemeh, Adhikari, Achyut, Graham, Charles J., Fontenot, Kathryn, Lewis Ivey, Melanie. "Monitoreo ambiental de las �reas de empaque de productos agr�colas frescos". 2017, Publication No. 3458-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Fontenot, Kathryn, Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Lewis Ivey, Melanie. "Pr�cticas de desinfecci�n de cosechas y campos: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3459-SPAN
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Mattison, C.P., Rai, R., Settlage, R.E., Hinchliffe, D.J., Madison, C., Bland, J.M., Brashear, S., Graham, C.J., Tarver, M.R., Florane, C. Bechtel, P.J. 2017. RNA-seq analysis of developing pecan (Carya illinoinensis) embryos reveals parallel expression patterns among allergen and lipid metabolism genes. J. Agri. Food Chem. 65(7):1443-1455.
• Type: Other Status: Published Year Published: 2017 Citation: Stephenson, Daniel O., Graham, Charles J., Miller, Donnie K., Mudge, Chris, Orgeron, Albert, Price, Randy R., Strahan, Ronald E., Webster, Eric P. Louisiana Suggested Chemical Weed Management Guide (online store item). 2017, Publication No. 1565, pp. 218.
• Type: Other Status: Published Year Published: 2017 Citation: Graham, C.J. 2017. Extreme weather, D�j� vu, and a chance to learn. Pecan South 50(8):12-15, 17.
• Type: Other Status: Published Year Published: 2017 Citation: Graham, C.J. 2017. So far, so good, but summer isnt over. Pecan South 50(5):6-10.
• Type: Other Status: Other Year Published: 2017 Citation: Graham, C.J. 2017. Warm winter may spell T-R-O-U-B-L-E. Pecan South 50(2):4, 16, 18.
• Type: Other Status: Published Year Published: 2017 Citation: Graham, C.J. 2017. Liebigs Law of the Minimum. Pecan South 49(11):8, 10, 12, 14.
• Type: Other Status: Published Year Published: 2017 Citation: Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Fontenot, Kathryn, Lewis Ivey, Melanie. "Agua agr�cola: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas (online only)". 2017, Publication No. 3441-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Graham, Charles J., Adhikari, Achyut, Malekian, Fatemeh, Fontenot, Kathryn, Lewis Ivey, Melanie. "Compostaje en la granja: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3460-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Fontenot, Kathryn, Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Lewis Ivey, Melanie. "Exclusi�n de animales en granjas: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3461-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Malekian, Fatemeh, Adhikari, Achyut, Graham, Charles J., Fontenot, Kathryn, Lewis Ivey, Melanie. "Buenas pr�cticas de higiene personal en una instalaci�n de empaque de productos agr�colas". 2017, Publication No. 3462-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Graham, Charles J., Adhikari, Achyut, Malekian, Fatemeh, Fontenot, Kathryn, Lewis Ivey, Melanie. "Uso de esti�rcol: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3463-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Fontenot, Kathryn, Adhikari, Achyut, Graham, Charles J., Malekian, Fatemeh, Lewis Ivey, Melanie. "Control de plagas en las �reas de empaque y de almacenamiento: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3464-SPAN
• Type: Other Status: Published Year Published: 2017 Citation: Graham, Charles J., Adhikari, Achyut, Malekian, Fatemeh, Fontenot, Kathryn, Lewis Ivey, Melanie. "Uso de pesticidas: las mejores pr�cticas para garantizar la inocuidad de los alimentos en granjas". 2017, Publication No. 3465-SPAN

Progress 02/29/16 to 09/30/16

Outputs
Target Audience:Audiences included both commercial and residential pecan growers in Louisiana. Additionally, commercial growers across the Southeastern Pecan Belt were targeted. Pecan evaluations andinformation from the applied pecan breeding program are developed for the growers, nursery industry, and homeowners in Louisiana and surrounding states with areas of similar environments. The scientific information developed in the areas of pecan genetics, pecan husbandry, and the health benefits of pecan nuts is aimed at the scientific community. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Meetings attended without presentation included the Southeastern Pecan Growers Association Conference in Destin, FL (served as Program Chair and Moderator of Educational program); Carya Crop Germplasm Committee Meeting in Las Cruces, NM; Western Pecan GrowersAssociation Conference in Las Cruces, NM;and the LSU Horticulture Prioritization meetings in Lafayette, LA and Baton Rouge, LA; How have the results been disseminated to communities of interest?Interviews on pecan orchards, production, disease, and marketing were conducted with LSU AgCenter Communications and the Louisiana Radio Network. Several articles were publishedin Pecan South magazine and a wide array of pecan topics were presented at meetings at the parish, state, and regional level. Outreach materials have been provided to health professionals, Extension Agents, and the general public. Information has been shared utilizing lectures and laboratory classes in the Lousiana Master Gardener Program. One-on-one audience contact has been by telephone, fax, station visits, on-farm visits, and grower meetings. Growing fruits and nuts in the homescape was discussed with clientele at a horticulture meeting in Winnfield, LA. Varietal selection and management of fruits and nuts recommended for Northwest LA was discussed at the Louisiana Nursery in Keithville, LA. A training program for Good Agricultural Practices (GAPs) and FSMA updates was held at Alexandria, LA. A GroupGAPs Training Workshop was held at the Lingo Center in Oakgrove, LA. The nutritional value of pecan kernels was discussed at the Louisiana Extension Association of Family & Consumer Sciences Conference in Natchitoches, LA. An oral presentation on FSMA and GAPs was given at the Oklahoma Pecan Growers Association Conference held at Tulsa, OK. A review of FSMA, GAPs, and GroupGAPs for pecan producers was discussed at the Ark-La-Miss Tri-State Conference in Alexandria, LA. The most recent guidelines on GAPs and GroupGAPs on pecan production in Louisiana, and an update on the Pecan Federal Marketing Order was presented at the Louisiana Farm Bureau Federation Conference in New Orleans, LA. Participated in the Small Fruit Consortium revising the blueberry and strawberry IPM guides. A GAPs Training Workshop was held in New Orleans, LA. Articles published in PecanSouth discussed how pecan was exempted from the final version of the FSMA Standards for the Growing, Harvesting, Packing, and Holding of Produce for Human Consumption rule, the effect of flooding on pecan tree growth and production, the development of GAPs and GroupGAPs program, and the effect of above average rainfall on cultural management success in a pecan orchard. What do you plan to do during the next reporting period to accomplish the goals?Continue care of thePecan Breeding orchard, which consists of seedlings originating from controlled crosses at the Pecan Research Station. Nut samples are evaluated annually to aid in selection of superior seedlings to be propagated for further testing in a commercial setting. Develop and evaluate rootstocks for potential use in commercial pecan production. Continue training and cultural management of the joint Pecan Demonstration orchard established in 2005. Yields and nut quality are evaluated on an annual basis. The orchard was recently used to evaluate the influence of powdery mildew on nut characteristics. Harvested nuts will also be used in food safety evaluations. Continuing working to develop science based processing technology to reduce food safety risk of Louisiana produced pecans. Identify the time and temperature parameters for hot water treatment during pecan processing that can be regarded as a kill step. Nut samples will be collected from pecan orchardswith or without cattle grazing as a cultural practice. These samples will be tested for the presence of E. coli, Salmonella, and Listeria pathogens. Continue collaborating with USDA scientists to characterize expression of allergens inpecan kernels.

Impacts
What was accomplished under these goals? The breeding program is targeted at originating new, early maturing, precocious, high yielding, regular bearing, disease and insect resistant, high quality pecan cultivars.Louisiana pecan orchards, including thePecanResearch Station, had very low production in 2015.Nuts were harvested on less than 25% of theseedling trees in the breeding orchard compared to the 2014 crop year. However,several controlled-cross seedlings which hadyielded consistently over the last several years were selected from the breeding orchard at the Pecan Research/Extension Station for propagation and evaluation in replicated trials to determine if they can be released as new pecan cultivars. Pecan samples of different varieties were collected and used in initial trials in pathogen reductions using hot water as a nut treatment. Thermal treatment is very effective with eliminating the risk of foodborne pathogens as required by the FSMA, and because of the hard surface of the pecans, higher temperature and short time treatment may be a suitable alternative for disinfecting common foodbarne pathogens. Laboratory studies are being performed to evaluate hot water and steam treatment to identify optimum parameters that could be regarded as a kill step without adversely affecting the quality of pecans. The transcriptome of apecan nut was characterized to identify the gene expression occurring during the process of nut development, specifically targeting those genes involved in fatty acid metabolism and those that commonly act as food allergens. Pecan samples were collected at the water, gel, dough, and mature nut stages of embryo development. Library preparation and sequencing was performed using Illumina based mRNA HiSeq with RNA from 4 time points during the growing season during August and September. Gene expression clustering analysis identified 12 different gene expression profiles, each containing a number of genes. Three pecan seed storage proteins that commonly act as allergens, Cari 1, 2, and 4 were significantly upregulated during the time course. We identified upregulated fatty acid metabolism genes involved in oleic and linoleic acid metabolism.

Publications

• Type: Journal Articles Status: Under Review Year Published: 2016 Citation: Mattison, C., Rai, R., Settlage, R., Hinchliffe, D., Madison, C., Bland, J. Brashear, S., Graham, C. Tarver, M., Florane, C. Bechtel, P. 2016. RNA-seq analysis of developing pecan (Carya illinoinensis) embryos reveals parallel expression patterns among allergen and lipid metabolism genes. J. Agri. Food Chem. (in Review).
• Type: Other Status: Published Year Published: 2016 Citation: Stephenson, Daniel O., Graham, Charles J., Griffin, James L., Miller, Donnie K., Mudge, Chris, Price, Randy R., Strahan, Ronald E., Webster, Eric P. Louisiana's Suggested Chemical Weed Management Guide (online store item). 2016, Publication No. 1565, pp. 214.
• Type: Other Status: Published Year Published: 2016 Citation: Graham, C.J. 2016. Tough year ends with an unexpected surprise. Pecan South 48(11):4, 16-17.
• Type: Other Status: Published Year Published: 2016 Citation: Graham, C.J. 2016. Rain, rain, go away, come again another day. Pecan South 49(2):6, 12, 19.
• Type: Other Status: Published Year Published: 2016 Citation: Graham, C.J. 2016. Pecans, FSMA, and GAPs, Oh My! Pecan South 49(5):4, 12.
• Type: Other Status: Published Year Published: 2016 Citation: Graham, C.J. 2016. The good and bad of abundant precipitation. Pecan South 49(8):4, 17.