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A cDNA encoding an ERE-binding protein (EgAP2-1) was isolated from the oil palm fruit mesocarp treated with ethylene using yeast one-hybrid assay. EgAP2-1 belongs to the AP2 subfamily of the APETALA2/ethylene-responsive factor (AP2/ERF) proteins and contains two highly conserved AP2/EREBP DNA-binding domains (DNA-BD). Sequence comparison of EgAP2-1 with other AP2 proteins revealed high conservation of the two AP2/EREBP domains and linker region among these proteins. Its protein was localized to the nucleus of onion epidermis cells and showed ERE-specific binding, transcriptional activation, and transactivation properties in yeast and in vitro. Its mRNA was highly expressed in oil palm mesocarp with elevated levels in ripening fruits but not in leaves and roots. EgAP2-1 was induced in mesocarp in response to ethylene and abscisic acid but not other hormonal stimuli, including methyl jasmonate and salicylic acid, and abiotic stresses including drought, cold, and high-salinity. Our results demonstrate a link between the regulation of EgAP2-1 expression and ethylene- and/or ABA-coordinated control of the fruit ripening and suggest a regulatory role for EgAP2-1 during fruit ripening and development in oil palm.

This dissertation examines the market and welfare impacts of three important policies and strategies affecting the, increasingly industrialized, agri-food marketing system. The first essay, Fair-Trade Coffee, examines the impact of the Fair Trade regime on coffee producers‘ welfare. The world coffee market has undergone a significant transformation in the past couple of decades: prices in producing countries have been declining while prices in consuming countries have been soaring. Fair Trade organizations have tried to address this price imbalance by providing an alternative method of trading aimed at increasing the prices received by coffee farmers. Despite their noble objectives, Fair Trade movements have had limited success in improving farmers welfare, however. This essay utilizes a novel framework of heterogeneous producers and relevant market information to provide insights on the market and welfare impacts of the Fair Trade regime when important idiosyncrasies of the Fair Trade production and marketing are included in the analysis. The objective of the second essay, Nebraska Bottle Bill, is to evaluate consumers welfare when a mandatory deposit on recyclable containers is applied in Nebraska. Nebraska is a throwaway society whose total and per-capita waste production has been increasing significantly for more than forty years. A bottle bill is an effective recycling program that encourages recycling rates greater than 90%. However, there are many opponents to bottle bills in the U.S. and these opponents argue that bottle bills and similar laws reduce consumers‘ welfare. This essay uses a Dynamic Almost Ideal Demand System (DAIDS) to evaluate the impact of the bottle bill on consumers‘ welfare in Nebraska. The third essay, Process Innovation Efficiency in the Canadian Food Manufacturing, evaluates the process innovation efficiency of food manufacturing firms in the prairie and western provinces in Canada. The level of productivity and efficiency in agricultur

The 1,053-bp promoter of the oil palm metallothionein gene (so-called MSP1) and its 5´ deletions were analyzed in transiently transformed oil palm tissues. The full length promoter showed 7-fold higher activity in the mesocarp than in leaves and 1.5-fold more activity than the CaMV35S promoter in the mesocarp. Two positive regulatory regions at nucleotides (nt) -953 to -619 and -420 to -256 regions and a negative regulatory region at -619 to -420 nt region were identified within the promoter sequence. Fine-tune deletion analysis of the -619 to -420 nt region led to the identification of a novel negative regulatory AGTTAGG core-sequence, responsible for controlling the fruit-specific activity of the MSP1promoter. Abscisic acid (ABA) and copper (Cu2+) induced the activity of the promoter and its 5´ deletions more effectively than methyl jasmonate (MJ) and ethylene. Regulatory DNA motifs responsive to ABA, copper, MJ, and ethylene were identified within the promoter sequence. These results suggest that the MSP1 promoter and its regulatory regions are potentially useful for engineering fruit-specific and inducible gene expression in oil palm. ABF family of transcription factors (TFs) play important regulatory roles in plant response to abiotic stresses as well as plant growth and development. Two ABA-responsive cDNA clones, named EABF and EABF1 were isolated from oil palm fruits using yeast one-hybrid system. EABF had a conserved AP2/EREBP DNA-binding domain (DNA-BD) and a potential nuclear localization sequence (NLS). No previously known DNA-BD was identified from the EABF1 sequence. EABF and EABF1 proteins were classified as DREB/CBF and bZIP family members based on the multiple sequence alignment and phylogenetic analysis. Both proteins showed ABRE-binding and transcriptional activation properties in yeast. Furthermore, both proteins were able to trans-activate the down-stream expression of the LacZ reporter gene in yeast. EABF was induced in response to ABA in oil p

The promoter of the oil palm metallothionein-like gene (MT3-A) demonstrated mesocarp-specific activity in functional analysis using transient expression assay of reporter gene in bombarded oil palm tissue slices. In order to investigate the tissue-specific expression of polyhydroxybutyrate (PHB) biosynthetic pathway genes, a multi-gene construct carrying PHB genes fused to the oil palm MT3-A promoter was co-transferred with a construct carrying GFP reporter gene using microprojectile bombardment targeting the mesocarp and leaf tissues of the oil palm. Transcriptional analysis using RT-PCR revealed successful transcription of all the three phbA, phbB, and phbC genes in transiently transformed mesocarp but not in transiently transformed leaf tissues. Furthermore, all the three expected sizes of PHB-encoded protein products were only detected in transiently transformed mesocarp tissues on a silver stained polyacrylamide gel. Western blot analysis using polyclonal antibody specific for phbB product confirmed successful translation of phbB mRNA transcript into protein product. This study provided valuable information, supporting the future engineering of PHB-producing transgenic palms.

Polyhydroxybutyrate is the most important type of polyhydroxyalkanoates (PHA), which is naturally synthesized by several microorganisms. Production of PHB in plants is based on the consumption of acetyl-CoA as an initial substrate, therefore oil palm being an oil crop serve as potential target due to its high flux of acetyl-CoA during the oil synthesis stage. In oil palm, mesocarp is the specialized tissue for oil synthesis. Targeting the expression of PHB genes in mesocarp tissue requires the mesocarp-specific regulation of these genes by a mesocarp-specific promoter, since accumulation of PHB in other tissues may have deleterious effects on the plant. Pervious efforts have resulted in isolation of promoter sequence of the oil palm mesocarp-specific metallothionein-like gene (designated MSP1) and preparation of the gene construct carrying PHB genes (pMS29 vector) to drive the specific expression of PHB genes (phbA, phbB, and phbC) in mesocarp tissue. Analysis of the specificity and strength of MSP1 and evaluating the expression pattern of the PHB genes in oil palm mesocarp tissue in a transient expression system will provide insight information prior to the stable transformation and supports time-saving strategy and more targeted and precise use of the technique. In this study, expression of PHB genes under the regulation of MSP1 was evaluated in a biolistic-based transient assay in transiently transformed oil palm mesocarp and leaf (control) tissue slices. Transcriptional and translational analysis of PHB genes was carried out by Reverse-transcriptase PCR (RT-PCR) and western blot techniques. RT-PCR analysis revealed that the engineering of PHB biosynthetic pathway genes under the regulation of MSP1 in transformed mesocarp tissue has resulted in successful transcription of phbA and phbB genes; however the phbC gene failed to produce any transcription product. In addition, RT-PCR analysis in non-transformed (non-bombarded) mesocarp tissues showed that there is no e