Restaurant and food service life cycle assessment and development of a sustainability standard

Purpose  

There is no clear guidance for responsible food service operations to reduce their environmental footprint, so the efforts put forth by a restaurant may not have the environmental impact intended. As a result, Green Seal conducted life cycle assessment research on restaurants and food service operations to define priorities for environmental improvement. This information was then used to develop a sustainability standard and certification (i.e., ecolabel) program.     

Golden bananas in the field: elevated fruit pro‐vitamin A from the expression of a single banana transgene

Vitamin A deficiency remains one of the world's major public health problems despite food fortification and supplements strategies. Biofortification of staple crops with enhanced levels of pro‐vitamin A (PVA) offers a sustainable alternative strategy to both food fortification and supplementation. As a proof of concept, PVA‐biofortified transgenic Cavendish bananas were generated and field trialed in Australia with the aim of achieving a target level of 20 μg/g of dry weight (dw) β‐carotene equivalent (β‐CE) in the fruit. Expression of a Fe'i banana‐derived phytoene synthase 2a (MtPsy2a) gene resulted in the generation of lines with PVA levels exceeding the target level with one line reaching 55 μg/g dw β‐CE . Expression of the maize phytoene synthase 1 (ZmPsy1) gene, used to develop ‘Golden Rice 2’, also resulted in increased fruit PVA levels although many lines displayed undesirable phenotypes. Constitutive expression of either transgene with the maize polyubiquitin promoter increased PVA accumulation from the earliest stage of fruit development. In contrast, PVA accumulation was restricted to the late stages of fruit development when either the banana 1‐aminocyclopropane‐1‐carboxylate oxidase or the expansin 1 promoters were used to drive the same transgenes. Wild‐type plants with the longest fruit development time had also the highest fruit PVA concentrations. The results from this study suggest that early activation of the rate‐limiting enzyme in the carotenoid biosynthetic pathway and extended fruit maturation time are essential factors to achieve optimal PVA concentrations in banana fruit.     

Developing a cell suspension system for Musa-AAA-EA cv. ‘Nakyetengu’: a critical step for genetic improvement of Matooke East African Highland bananas

Embryogenic cell suspensions of triploid East African Highland bananas (Musa AAA-EA) were initiated and generated using cooking cultivar ‘Nakyetengu’ belonging to the Nakabululu clone set. Immature male flowers produced embryogenic calli consisting of embryos and friable tissue after 4 mo culture on a modified MA1 callus induction medium. Friable calli were initiated and maintained in liquid MA2 medium. A cell growth rate of 1.5–2.0 sedimented cell volume (SCV) per month was observed. Embryo development was observed at 2.18?×?10³ embryos per mL SCV. Germination of these embryos was observed at 2.8% and 6.2% for two cell suspension lines. Plant regeneration efficiency was 60–100%, all producing normal plants with a shoot and roots at weaning. In the field, somatic cell-derived plants were all normal morphology and comparable to control plants during vegetative and reproductive stages. This study is a breakthrough for recalcitrant East African Highland banana and offers a system that can provide essential raw materials for associated germplasm improvement through genetic engineering approaches.     

Effects of two pheromone trap densities against banana weevil, Cosmopolites sordidus, populations and their impact on plant damage in Uganda

Abstract:  An on-farm study to evaluate the effect of pheromone trap density on the population of the banana weevil, Cosmopolites sordidus (Germar) (Col., Curculionidae) was conducted in Masaka district, Uganda. The pheromone used was Cosmolure+, a commercially available weevil aggregation pheromone. Forty-two farms were assigned to one of three treatments: 0, 4 and 8 pheromone traps/ha. Pheromone lures were changed monthly at which time the traps were moved to a different location within the stand. Adult weevil population densities were estimated by using mark and recapture methodology at 0, 6, 12, 18 and 21 months, while damage to the banana corm was assessed at 0, 3, 6, 12, 18 and 21 months since the start of the experiment. Pheromone trap captures were generally low: about 10 weevils per trap per month. There were no significant differences in mean catches of C. sordidus per trap per month except for February 2002 when doubling the pheromone trap density decreased weevil catches. Although not significant, decreased efficiency was also the trend in higher trap densities over all the data sets. Doubling the number of traps increased the number of weevils caught per hectare per month from 0.4 to 0.6%. There was no significant difference in plant damage between the pheromone treatments in low- compared with high-trap densities. There were generally no significant differences in weevil populations and plant damage between pheromone-treated and control farms. Possible reasons for the low-trap efficacy in this study are discussed.     

Nematode 18S rRNA gene is a reliable tool for environmental biosafety assessment of transgenic banana in confined field trials

Information on relatedness in nematodes is commonly obtained by DNA sequencing of the ribosomal internal transcribed spacer region. However, the level of diversity at this locus is often insufficient for reliable species differentiation. Recent findings suggest that the sequences of a fragment of the small subunit nuclear ribosomal DNA (18S rRNA or SSU), identify genera of soil nematodes and can also distinguish between species in some cases. A database of soil nematode genera in a Ugandan soil was developed using 18S rRNA sequences of individual nematodes from a GM banana confined field trial site at the National Agricultural Research Laboratories, Kawanda in Uganda. The trial was planted to evaluate transgenic bananas for resistance to black Sigatoka disease. Search for relatedness of the sequences gained with entries in a public genomic database identified a range of 20 different genera and sometimes distinguished species. Molecular markers were designed from the sequence information to underpin nematode faunal analysis. This approach provides bio-indicators for disturbance of the soil environment and the condition of the soil food web. It is being developed to support environmental biosafety analysis by detecting any perturbance by transgenic banana or other GM crops on the soil environment.     

Leaching and crop recovery of15N from ammonium sulphate and labelled maize (Zea mays) material in lysimeters at a site in Zimbabwe

The fate of¹⁵N-ammonium sulphate fertilizer that was applied to four lysimeters in the 1990/91 summer was studied over three consecutive growing seasons during which either maize or wheat was grown. Aboveground portions of¹⁵N-labelled maize plants from the first harvest were applied to four other lysimeters at 5 t ha^–1. Two lysimeters in each of the sets of four were assigned a low and a high moisture treatment using irrigation. In both moisture treatments, plant recovery of fertilizer-¹⁵N in the first season was 27% and a further 2% was recovered by plants during the next two seasons. During the second and third seasons, total recovery of¹⁵N by aboveground plant portions from lysimeters that received¹⁵N-labelled maize material was equivalent to 2.5% of applied fertilizer-¹⁵N. This corresponded to ca. 18% recovery of the¹⁵N added in maize material. Leaching of fertilizer-N over the three growing seasons did not exceed 0.3% in total. During the first season, a maximum of 0.25 kg N ha^–1, equivalent to 0.25% of the applied fertilizer-N, was leached in the high moisture treatment. This represented 1.8% of the nitrate load in leachates. Less than 0.002% of the applied fertilizer-N was leached in the low moisture treatment during the first season.     

Transgenic banana expressing Pflp gene confers enhanced resistance to Xanthomonas wilt disease

Banana Xanthomonas wilt (BXW), caused by Xanthomonas campestris pv. musacearum, is one of the most important diseases of banana (Musa sp.) and currently considered as the biggest threat to banana production in Great Lakes region of East and Central Africa. The pathogen is highly contagious and its spread has endangered the livelihood of millions of farmers who rely on banana for food and income. The development of disease resistant banana cultivars remains a high priority since farmers are reluctant to employ labor-intensive disease control measures and there is no host plant resistance among banana cultivars. In this study, we demonstrate that BXW can be efficiently controlled using transgenic technology. Transgenic bananas expressing the plant ferredoxin-like protein (Pflp) gene under the regulation of the constitutive CaMV35S promoter were generated using embryogenic cell suspensions of banana. These transgenic lines were characterized by molecular analysis. After challenge with X. campestris pv. musacearum transgenic lines showed high resistance. About 67% of transgenic lines evaluated were completely resistant to BXW. These transgenic lines did not show any disease symptoms after artificial inoculation of in vitro plants under laboratory conditions as well as potted plants in the screen-house, whereas non-transgenic control plants showed severe symptoms resulting in complete wilting. This study confirms that expression of the Pflp gene in banana results in enhanced resistance to BXW. This transgenic technology can provide a timely solution to the BXW pandemic.     

Comparative life cycle assessment of conventional and Green Seal-compliant industrial and institutional cleaning products

Purpose  

The goal of this study was to use life cycle assessment (LCA) methodology to assess the environmental impacts of industrial and institutional cleaning products that are compliant with the Green Seal Standard for Cleaning Products for Industrial and Institutional Use, GS-37, and conventional products (non-GS-37-compliant) products.