Viability assessment for the use of floating treatment wetlands as alternative production and remediation systems for nursery and greenhouse operations.

Floating treatment wetlands (FTWs) are deployed in nursery and greenhouse water retention reservoirs to help manage and mitigate nutrient contaminants within irrigation return flow. One management issue for FTWs is the need for plant harvest to avoid releasing nutrients back into the water column when plant tissues begin to senesce. Some researchers recommend harvesting the entire plant to prevent nutrient release. Resale of plants harvested from FTWs is one possible use of this live biomass by the nursery and greenhouse industry. To determine if nursery and greenhouse operations could use FTWs to clean water and simultaneously produce saleable plants, the objectives of this study were to (1) quantify the survival and aesthetics of plants after transplant from a FTW and (2) compare the time to market between traditional (containerized) and FTW production systems. Overall, plants harvested from FTWs were resalable. Plants transplanted from FTWs had higher survival and aesthetic ratings (scale of 1-5, 5 = highest quality) when transplanted to containers (4.26) compared to directly into the ground (2.81). The growth of Panicum virgatum and Canna × generalis 'Firebird' in FTW systems was two weeks slower than that of plants grown in traditional production areas. Sustainability of FTW systems combined with the capacity to produce salable plants that will return a profit improves adoption feasibility for production horticulture.

How Consistent Are Consumers in Their Decisions? Investigation of Houseplant Purchasing.

This paper examines the impact of intrinsic consumer attributes on decision consistency in houseplant purchasing intentions. Subjects reported their likelihood to buy (LTB) for themselves and as a gift at perceived bargain and getting expensive price levels. The sample was analyzed according to those who switched their LTB ratings to relatively lower values versus subjects who did not by using their demographic characteristics and responses to plant buying behavior questions. Secondly, subjects who had high initial purchase intents were analyzed versus those who had low initial purchase intents. The results indicate that inconsistent purchase decisions are more likely to occur at the perceived getting expensive price level than the perceived bargain price points. Additionally, there are very few demographic differences among the plant buyers who are consistent with their purchase intent versus inconsistent, indicating that external environmental cues may have more of an influence on purchase consistency than intrinsic cues. This information can be utilized by greenhouse and retail firms to understand when a consumer is less likely to change their plant purchase decision with a high initial intent. These price points can help firms optimize their current price offerings within the market and create dialogues with partnering box stores.

Genome wide association identifies novel loci involved in fungal communication.

Understanding how genomes encode complex cellular and organismal behaviors has become the outstanding challenge of modern genetics. Unlike classical screening methods, analysis of genetic variation that occurs naturally in wild populations can enable rapid, genome-scale mapping of genotype to phenotype with a medium-throughput experimental design. Here we describe the results of the first genome-wide association study (GWAS) used to identify novel loci underlying trait variation in a microbial eukaryote, harnessing wild isolates of the filamentous fungus Neurospora crassa. We genotyped each of a population of wild Louisiana strains at 1 million genetic loci genome-wide, and we used these genotypes to map genetic determinants of microbial communication. In N. crassa, germinated asexual spores (germlings) sense the presence of other germlings, grow toward them in a coordinated fashion, and fuse. We evaluated germlings of each strain for their ability to chemically sense, chemotropically seek, and undergo cell fusion, and we subjected these trait measurements to GWAS. This analysis identified one gene, NCU04379 (cse-1, encoding a homolog of a neuronal calcium sensor), at which inheritance was strongly associated with the efficiency of germling communication. Deletion of cse-1 significantly impaired germling communication and fusion, and two genes encoding predicted interaction partners of CSE1 were also required for the communication trait. Additionally, mining our association results for signaling and secretion genes with a potential role in germling communication, we validated six more previously unknown molecular players, including a secreted protease and two other genes whose deletion conferred a novel phenotype of increased communication and multi-germling fusion. Our results establish protein secretion as a linchpin of germling communication in N. crassa and shed light on the regulation of communication molecules in this fungus. Our study demonstrates the power of population-genetic analyses for the rapid identification of genes contributing to complex traits in microbial species.