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Sweetpotato breeding over the years solely depended on sensory evaluation for domestic uses, thereby downplaying the need for adjustment of breeding objectives and selection procedures to cater for industrial potential. This study was conducted to evaluate ten elite genotypes of sweetpotato for diversified utilization and commercialization. These genotypes had been selected over the years for high dry matter and starch content according to the preference of Ghanaian consumers. Analyses were carried out on key nutrient components, pasting properties, and starch granule morphology using near infrared reflectance spectroscopy, rapid viscosity analysis, and light microscopy, respectively. Sensory evaluation was carried out using a focus group approach. Based on functional diversity and unique combinations of quality traits identified, the genotypes were found to have several potential applications in the food industry. These include fufu flour, bread, pastries, French fries, gluten-free noodles, yogurt filler, baby food, juices, and raw material for brewery and other industries. These elite genotypes, when released as new varieties, can immensely contribute to a more diversified use of sweetpotato in Ghana and ultimately contribute to the enhancement of food and job security.

Children’s diets can have major implications for a wide range of diseases and their development outcomes. In Africa, micronutrient deficiency remains a major challenge and affects the health and development of vulnerable populations, especially children. A major effort to combat micronutrient deficiency has targeted biofortification of staple foods, with greatest potential being registered in the enrichment of, among others, sweetpotato with beta carotene—a precursor for vitamin A. However, overcoming vitamin A deficiency is made all the more complicated by children’s general resistance to unfamiliar foods. We report the results of a field experiment in Nigerian schools designed to use behavioral techniques to promote consumption of an unfamiliar food: the pro-vitamin A rich orange-fleshed sweetpotato. We find that children eat more, on average, when the sweetpotato is introduced alongside behavioral nudges such as songs or association with aspirational figures. These results appear to conform to results found in a developed country context.

This research provides a guide to sweetpotato breeders for developing and deploying appropriate sweetpotato cultivars capable of meeting targeted consumer needs for sweetpotato fries and other fried sweetpotato products in distinct segments. It will also enable stakeholders in the sweetpotato value chain strategise in order to increase sweetpotato adoption., Summary Prepared foods are increasing in popularity in West Africa alongside rapid urbanisation. Growing demand for fried products calls for targeted breeding efforts to meet consumer needs, but little is known regarding consumer preferences. This research identified the sensory attributes of fried sweetpotato preferred by different consumer groups using a combination of consumer acceptance testing and descriptive sensory analysis. Market and community surveys identified three consumer segments in Ghana and Nigeria with contrasting preferences for fried sweetpotato sensory attributes. One group preferred crispy, crunchy, mealy and sweet fried sweetpotato; another preferred characteristic yam flavour and dry texture; and the third preferred uniform orange colour appearance, ripe plantain flavour and palm nutty flavour. Such consumer segmentation can help emerging West African fried sweetpotato industries identify target markets and provides valuable information to breeders, growers and retailers to prioritise attributes in their breeding, growing or product sourcing decisions.

Quality and psychosocial factors influencing the purchase of orangefleshed sweetpotato bread, process for determining drivers for orange‐fleshed sweetpotato bread., Summary Fried sweetpotato quality is important for variety adoption in West Africa. To inform breeding efforts, the study developed a product profile for sweetpotato chunk fries using mixed qualitative and quantitative methods. Root characteristics, processing attributes, in‐mouth attributes and appearance of fried product were critical to final product quality. Raw roots should be hard, have smooth skin and no off‐odours. Peeled roots should be hard to slice and not sticky. Stickiness and moist surface indicate high moisture content, associated with excessive oil absorption during frying. Hard to slice roots connote high dry matter. Fried product should be crisp, slightly sugary and mealy, have a uniform colour with brown tint and not be soggy. Crispness, mealiness and short frying time with limited oil absorption may be functions of starch. Understanding starch characteristics and other attributes that contribute to quality fried sweetpotato is critical for breeding sweetpotato genotypes with superior quality for frying.

Two proposed containers (50 kg-polypropylene sack and 50 kg-wooden crate) were compared with existing packaging containers (100 kg-polypropylene and jute sacks) to transport sweetpotato storage roots from major aggregation sites to distant urban market centers. The extent of breaks, bruises and the impacts, incurred by storage roots packaged in the different containers, were assessed. Additionally, at the urban market centers, the visual quality of the transported storage roots was evaluated by both aggregators and consumers. The benefit cost ratio (BCR) for each of packaging options was calculated to ascertain their profitability for sweetpotato roots transportation. The existing polypropylene/jute sacks resulted in significant major breakages in both years (p = 0.028, 0.016) after transportation for the Afram Plains-Accra route in truck. The donkey-driven carts or tricycles used for the Bawku-Bitou route did not show any significant (p > 0.05) influence on the storage roots contained in the existing polypropylene/jute sacks. The average impact recorded at both loading and offloading sites was significantly different (13.4 - 19.3 g vs. 0 - 30.0 g; p = 0.045) for all the containers. The proposed 50 kg-woodencrate had a significantly superior (mean rank of 127; p < 0.0001) visual quality compared with the other packages. All the packaging options showed profitability, because they had a BCR > 1.40, except for the 50 kg-wooden-crate. The 50 kg-polypropylene container delivered better quality roots to urban market centers than the existing packaging containers, and was more profitable than the 50 kg-wooden crates. The 50 kg-polypropylene container is recommended for the transport of sweetpotato storage roots in Ghana.

Sweetpotato is a resilient food crop with great potential to contribute to reduced hunger in the world. Sweetpotato shows significant potential to contribute to reducing the Global Hunger Index, which reflects deficiencies in calories and micronutrients based on the components of hunger, undernourishment, under-five mortality rate, stunting and wasting. Its genetic diversity has been harnessed through breeding to increase vitamin A, iron, and zinc content, virus resistance and climate resilience for the world's food needs. Africa and India are the most food-insecure regions. The main objectives of this research were to: provide information and a knowledge base on sweetpotato breeding in Africa for biofortification of vitamin A, iron, and zinc, drought tolerance and virus resistance; recommend procedures for generating new breeding populations and varieties; and develop new tools, technologies and methods for sweetpotato improvement. The research was implemented between 2009 and 2020 in 14 collaborating African countries using introduced and local genotypes. The redesigned accelerated breeding scheme resulted in increased genetic gains for vitamin A, iron, zinc contents and virus resistance, and the release by sub-Saharan African countries of 158 varieties; 98 of them orange-fleshed; 55 varieties bred by an accelerated breeding scheme; 27 drought-tolerant and two with enhanced iron and zinc content. Our experience has demonstrated that through the use of more optimized, standardized and collaborative breeding procedures by breeding programs across Africa, it is possible to speed official sweetpotato variety release and contribute to reducing the severe micronutrient deficiencies on the continent.

This study sought to understand user preferences of raw, boiled and steamed sweetpotato, a staple food in Uganda. A sequential methodology involving state of knowledge review, gendered food mapping, processing diagnosis and consumer testing was used in Lira and Kamwenge districts. Preferred raw sweetpotato characteristics, were large roots (≥ 3 cm diameter) with a sweet taste, smooth skin and hard texture, while mealiness, sweet taste and good sweetpotato smell were important attributes for boiled sweetpotato. Processors, mostly women, highlighted ease of peeling and sappiness of raw roots. There were gender differences in quality characteristic preferences and perceived importance. The released variety, NASPOT 8, had the highest overall liking in Kamwenge and was well‐liked in Lira. Penalty analysis of consumer data showed that sweetness and firmness were key drivers of overall liking. The results will support breeding programmes in meeting specific end‐user product profiles, selection criteria and uptake of new varieties., Summary This study sought to understand user preferences of raw, boiled and steamed sweetpotato, a staple food in Uganda. A sequential methodology involving state of knowledge review, gendered food mapping, processing diagnosis and consumer testing was used in Lira and Kamwenge districts. Preferred raw sweetpotato characteristics were large roots (≥ 3 cm diameter) with a sweet taste, smooth skin and hard texture, while mealiness, sweet taste and good sweetpotato smell were important attributes for boiled sweetpotato. Processors, mostly women, highlighted ease of peeling and sappiness of raw roots. There were gender differences in quality characteristic preferences and perceived importance. The released variety, NASPOT 8, had the highest overall liking in Kamwenge and was well liked in Lira. Penalty analysis of consumer data showed that sweetness and firmness were key drivers of overall liking. The results will support breeding programmes in meeting specific end‐user product profiles, selection criteria and uptake of new varieties.

Despite sustained economic growth and reduction in some of forms of malnutrition, Ghana still faces a national prevalence rate of 20.8% vitamin A deficiency (VAD) among for children 6–59 months old. Orange-fleshed sweetpotato ( Ipomoea batatas L.) (OFSP) can significantly improve vitamin A intake and contribute toward reducing VAD, especially in Northern Ghana where VAD is 31% among young children. Several poverty and nutrition projects in Ghana have promoted the use of OFSP for its health benefits. This study assesses the effect of three varietial attributes on adoption of the first released OFSP variety in Northern Ghana namely, Apomuden. The study concluded that sweetness, taste and dry matter have joint significant effects on adoption of an OFSP variety. The positive and negative traits highlighted will inform the on-going breeding effort.

Literature review reveals high potential for commercially important fried sweetpotato in West Africa. Sweetpotato is also widely consumed in other forms. Additional knowledge will inform breeding strategies to improve sweetpotato for frying and other uses., Summary This review provides background about sweetpotato in West Africa to identify the current importance and future potential of sweetpotato fried products in the region. We drew on global literature to consider current best practices and health aspects in addition to information from West Africa where frying in the form of large wedges or ‘chunk fries’ is predominant over other forms (i.e. chips (often referred to as crisps in England and the Commonwealth) and ‘French fries’). Chunk fries are produced mostly by female‐run microenterprises selling them as a filling snack to roadside and market customers. Boiling, drying and reconstituting in various foods, pounding and consumption of leaves as a vegetable are also important in the region. Further research will inform the development of a product profile for chunk fried sweetpotato and inform breeding strategies to improve sweetpotato for frying and other uses.

This study estimated the amount of loss in storage roots caused by various levels of damage caused by sweetpotato weevils (Cylas spp). Seven varieties of sweetpotato (Ipomoea batatas L. (Lam)) were evaluated in three production sites in northern Ghana for two years (2014 and 2015). Yield data for each experimental plot were collected. A regression analysis was carried out using the generalized linear model approach. In the study, nonmarketable roots were classified as all undersized roots (

Commercialization of sweetpotato vines is persistent if multipliers show evidence of superiority of their vines. This study aimed at evaluating the effects of net tunnel source and of pathogen-tested planting material compared to “apparently” healthy vines on yield and health status at three defined environments in Northern Ghana during the rainy season of 2015. Sweetpotato virus disease (SPVD) and weevils were considered. Four varieties were investigated, the pathogen-tested vines of Dadanyuie, Bohye and Ligri, and “apparently” healthy vines of Apomuden from the negative selection technique. All planting materials taken from the net tunnel and open field were from the same location. Eight treatment combinations were arranged in a RCBD with 3 replicates. Planting distance was 0.30 m x 1 m. Weeding was done and fertilizer was applied as necessary. General and three-way analysis of variance were computed using Genstat. Highly significant differences were found among varieties and trial sites for plant establishment, foliage yield, root yield, weevil, and SPVD. The two sources were not significantly different. For varieties across sites, net tunnel source was better than open field. The apparently healthy vines might be effective as pathogentested vines. Net tunnels may have a distinct advantage for multiplication and maintenance.

Molecular markers are needed for enhancing the development of elite sweetpotato (Ipomoea batatas (L.) Lam) cultivars with a wide range of commercially important traits in sub-Saharan Africa. This study was conducted to estimate the heritability and determine trait correlations of storage root yield, dry matter, starch and β-carotene content in a cross between ‘New Kawogo’ × ‘Beauregard’. The study was also conducted to identify simple sequence repeat (SSR) markers associated with these traits. A total of 287 progeny and the parents were evaluated for two seasons at three sites in Uganda and genotyped with 250 SSR markers. Broad sense heritability (H2) for storage root yield, dry matter, starch and β-carotene content were 0.24, 0.68, 0.70 and 0.90, respectively. Storage root β-carotene content was negatively correlated with dry matter (r = −0.59, P < 0.001) and starch (r = −0.93, P < 0.001) content, while storage root yield was positively correlated with dry matter (r = 0.57, P = 0.029) and starch (r = 0.41, P = 0.008) content. Through logistic regression, a total of 12, 4, 6 and 8 SSR markers were associated with storage root yield, dry matter, starch and β-carotene content, respectively. The SSR markers used in this study may be useful for quantitative trait loci analysis and selection for these traits in future.

Experimental error, especially through genotype misclassification and pedigree errors, negatively affects breeding decisions by creating ‘noise’ that compounds the genetic signals for selection. Unlike genotype-by-environment interactions, for which different methods have been proposed to address, the effect of ‘noise’ due to pedigree errors and misclassification has not received much attention in most crops. We used two case studies in sweetpotato, based on data from the International Potato Center’s breeding program to estimate the level of phenotype misclassification and pedigree error and to demonstrate the consequences of such errors when combining phenotypes with the respective genotypes. In the first case study, 27.7% phenotype misclassification was observed when moving genotypes from a diversity panel throughin-vitro, screenhouse and field trialing. Additionally, 22.7% pedigree error was observed from misclassification between and within families. The second case study involving multi-environment testing of a full-sib population and quantitative trait loci (QTL) mapping showed reduced genetic correlations among pairs of environments in mega-environments with higher phenotype misclassification errors when compared to the mega-environments with lower phenotype misclassification errors. Additionally, no QTL could be identified in the low genetic correlation mega-environments. Simulation analysis indicated that phenotype misclassification was more detrimental to QTL detection when compared to missingness in data. The current information is important to inform current and future breeding activities involving genomic-assisted breeding decisions in sweetpotato, and to facilitate putting in place improved workflows that minimize phenotype misclassification and pedigree errors.

Sweetpotato (Ipomoea batatas L. (Lam)) is a nutritious food security crop for most tropical households, but its utilisation is very low in Ghana compared to the other root and tuber crops due to lack of end-user-preferred cultivars. Knowledge on the genetic control of important traits such as dry matter, starch and sugar content of sweetpotato storage roots in a breeding population is critical for making breeding progress in developing sweetpotato varieties preferred by farmers and consumers. This study used diallel mating design to elucidate general combining ability and specific combining ability, to determine the gene action controlling storage root dry matter, starch and sugar content in sweetpotato and the heterotic potential of the traits to facilitate the crop’s improvement for increased utilisation. A general model for estimating genetic effects, GEAN II, was used to analyse the data. Genetic variability was seen for dry matter, starch and sugar content of sweetpotato and much of this gene...

Sweetpotatoes utilization is low in Ghana due to lack of farmer and consumer preferred cultivars. Poor flowering and incompatibilities among genotypes limit breeding progress in its improvement. The objective was to assess compatibilities among sweetpotato genotypes to select good parents for breeding end-user preferred varieties for increased utilization. Twenty-one genotypes selected from 115 accessions evaluated across three contrasting environments were crossed using full diallel mating scheme. In all, 6388 crosses were carried out and 3214 seeds produced. This study sought to understand the genetic incompatibilities based on the number of seeds set per capsule after self- or cross-fertilization. Lack of flowering or poor flowering, and self- and cross-incompatibilities were major constraints to sweetpotato improvement found. Four genotypes (Histarch, Apomuden, Beauregard, and Ogyefo) were the best parents based on cross compatibilities and they can be used to determine the genetic control of beta-carotene, dry matter and sugar contents in sweetpotato. Histarch and Ogyefo are recommended as parents for the development of non-sweet, high dry matter sweetpotato varieties that are the preferred cultivars in Ghana because of their low sugar content. Use of many genotypes in hybridization and establishment of crossing blocks Hybridization in the minor cropping season is highly recommended.

This study assessed the genetic diversity and differentiation in sweetpotato accessions in Ghana to guide selection for genetic improvement on beta-carotene, dry matter and sugar contents to promote increased utilization. One hundred and fifteen sweetpotato accessions from four different sources, which were the International Potato Centre (CIP) collection, local collection from farmers’ field, local improved varieties, and local and exotic collections from the National Agricultural Research Programmes were studied using 40 agro-morphological and physico-chemical traits, and 25 SSR markers. Variability was obtained for 13 agro-morphological traits and all the physico-chemical traits. Significant genetic diversity indicates existence of a high degree of agro-morphological and physicochemical variation. Within Group variation (97%) accounted for most of the diversity indicating a broad genetic base. The divergence indicates that breeders can form different populations with significant levels of genetic variation to exploit heterosis and improvement of populations. A strong negative relationship was found for sugar content and dry matter content and indicates a possible development of non-sweet high dry matter sweetpotato varieties. However, developing non-sweet, high dry matter and high beta-carotene sweetpotato varieties could be challenging due to the strong negative association between dry matter content and beta-carotene content, and the positive association existing between beta-carotene and sugar content. This study has in addition confirmed the breeding potential of sweetpotato accessions in Ghana and the probability of providing useful genetic variation for the development of farmer preferred cultivars. Key words: Analysis of Molecular Variance (AMOVA), diversity, end-user, simple sequence repeats (SSR) markers, Sweetpotato, traits.

Commonly used innovation adoption models indirectly assume homogenous information flow across farmers, which is often not the case. For new and or not widely known technologies, such as orange-fleshed sweetpotato (OFSP) varieties, exposure plays an important role in farmers’ decision to adopt. OFSP varieties have been shown to be highly effective means of combating Vitamin A deficiency at the community level because of their high pro-vitamin A content and cost effectiveness as compared with fortification and supplementation. Significant efforts, including the implementation of the Jumpstarting Orange-fleshed Sweetpotato in West Africa through Diversified Markets project, have gone into promoting the production and consumption of OFSP in West Africa over the last decade. Observations in the project countries indicated that the usage rate of OFSP among the beneficiaries was extremely high, suggesting a significant link between exposure through awareness creation activities and adoption behavior. This study empirically examines the role of exposure to OFSP adoption. A multistage sampling technique was used to select farmers. Data were collected via face-to-face interviews with 345 and 381 sweetpotato farmers in Ghana and Nigeria respectively, using structured questionnaires. The study adopted the counterfactual outcome framework from the modern evaluation approach. We found that the OFSP adoption rates in 2016 could have been nearly 61% in Ghana and 42% in Nigeria, instead of the observed sample adoption rate of 51 and 33%, respectively, if the whole population was exposed to the OFSP varieties. This suggests that there is potential for increasing OFSP adoption rates through intensified dissemination and awareness creation activities. We also found that the OFSP adoption is influenced by a number of other factors, which varied between the study countries. This implies that interventions to increase the adoption rate shouldn't use “one size fits all”, but rather targeted approaches.

Quality assurance and control (QA/QC) is an essential element of a breeding program’s optimization efforts towards increased genetic gains. Due to auto-hexaploid genome complexity, a low-cost marker platform for routine QA/QC in sweetpotato breeding programs is still unavailable. We used 662 parents of the International Potato Center (CIP)’s global breeding program spanning Peru, Uganda, Mozambique and Ghana, to develop a low-density highly informative single nucleotide polymorphism (SNP) marker set to be deployed for routine QA/QC. Segregation of the selected 30 SNPs (two SNPs per base chromosome) in a recombined breeding population was evaluated using 282 progeny from some of the parents above. The progeny were replicated from in-vitro, screenhouse and field, and the selected SNP-set was confirmed to identify relatively similar mislabeling error rates as a high density SNP-set of 10,159 markers. Six additional trait-specific markers were added to the selected SNP set from previous quantitative trait loci mapping. The 36-SNP set will be deployed for QA/QC in breeding pipelines and in fingerprinting of advanced clones or released varieties to monitor genetic gains in famers fields. The study also enabled evaluation of CIP’s global breeding population structure and the effect of some of the most devastating biotic stresses like sweetpotato virus disease on genetic variation management. These results will inform future deployment of genomic selection in sweetpotato.Key MessageA 36-SNP diagnostic marker set has been developed for quality assurance and control to support global sweetpotato breeding optimization efforts. Breeding population structure is shaped by sweetpotato virus disease prevalence.

Aims: T o determine the effects of sodium metabisulphite and blanching pretreatments on the quality characteristics of yam bean ( Pachyrhizus erosus ) flour. Study Design: Evaluation of the effects of peeling, blanching and sodium metabisulphite pretreatments on the ease of drying, particle size distribution, colour and pH of yam bean flour using a 2 x 3 factorial design. Place and Duration of Study : Yam bean roots were ob tained from the CSIR - Crops Research Institute, Kumasi, Ghana. All reagents used were obtained from accredited suppliers in Accra

Sweet potato has traditionally been viewed as a “poor person’s crop” or “orphan crop,” and it has attracted limited attention compared to other staple crops. However, during the last decade, this perception has changed, and it is widely acknowledged that sweet potato has great potential to contribute to the alleviation of malnutrition and hunger in the developing world. Orange-fleshed sweet potato, in particular, with its high provitamin A content, has become a prominent example of the effectiveness of biofortified staple crops to combat vitamin A deficiency. Similarly, increasing awareness of the nutritional value of sweet potato is driving consumer demand among health-conscious consumers globally, and its potential use in a wide range of value-added human and animal products is widely recognized. As the public and private sectors learn more about the benefits and opportunities of sweet potato, they have invested more in crop improvement; thus our understanding of the importance and potential of the crop is increasing.

Sweetpotato (Ipomoea batatas Lam) is a staple food globally, but it has remained underutilised resource in Ghana due to lack of consumer preferred cultivars. There is the need to develop staple-type sweetpotato cultivars which are preferred by consumers to increase sweetpotato use as a food security, health and industrial crop commodity in Ghana. This study was conducted to evaluate the breeding potential of sweetpotato germplasm for the development of farmer and consumer preferred varieties in Ghana. A total of 115 sweetpotato accessions were evaluated for genetic variability. Significant (P

Scope Anthocyanins, the natural pigments in plant foods, have been associated with cancer prevention. However, the content of anthocyanins in staple foods is typically low and the mechanisms by which they exert anticancer activity is not yet fully defined. Methods and results We selected an anthocyanin-enriched purple-fleshed sweet potato clone, P40, and investigated its potential anticancer effect in both in vitro cell culture and in vivo animal model. In addition to a high level of total phenolics and antioxidant capacity, P40 possesses a high content of anthocyanins at 7.5 mg/g dry matter. Treatment of human colonic SW480 cancer cells with P40 anthocyanin extracts at 0-40 μM of peonidin-3-glucoside equivalent resulted in a dose-dependent decrease in cell number due to cytostatic arrest of cell cycle at G1 phase but not cytotoxicity. Furthermore, dietary P40 at 10-30% significantly suppressed azoxymethane-induced formation of aberrant crypt foci in the colons of CF-1 mice in conjunction with, at least in part, a lesser proliferative PCNA and a greater apoptotic caspase-3 expression in the colon mucosal epithelial cells. Conclusion These observations, coupled with both in vitro and in vivo studies reported here, suggest anthocyanin-enriched sweet potato P40 may protect against colorectal cancer by inducing cell-cycle arrest, antiproliferative, and apoptotic mechanisms.

Cooking can significantly alter sugar content of sweet potato roots. Sweet potato roots were processed using three different cooking treatments, with the aim of investigating the effects of these methods on sugar profile and sweetness levels. Significant contribution of the cooking treatment and genotype, and their interaction on levels of the sugars were also determined. Moreover, sugar values were converted to relative sweetness per sucrose equivalent. The results revealed that cooking treatment produced the highest effect on sugar except fructose. Variability due to the interactions was significant and ranged from 2.60% to 11.74%. Whilst sucrose was the predominant in the raw form, maltose increased dramatically during cooking. Sweetness level increased substantially upon cooking and was highly dependent on initial sugar content, amylase activity and cooking treatment. Thus, evaluation of sweetness levels in sweet potato clones should not only be on the uncooked samples but should take into account the cooking methods employed.

The sustainability of soil quality under high tunnels will influence management of high tunnels currently in use and grower decisions regarding design and management of new high tunnels to be constructed. Soil quality was quantified using measures of soil pH, salinity, total carbon, and particulate organic matter (POM) carbon in a silt loam soil that had been in vegetable production under high tunnels at the research station in Olathe, KS, for eight years. Soil under high tunnels was compared with that in adjacent fields in both a conventional and an organic management system. The eight-year presence of high tunnels under the conventional management system resulted in increased soil pH and salinity but did not affect soil carbon. In the organic management system, high tunnels did not affect soil pH, increased soil salinity, and influenced soil carbon (C) pools with an increase in POM carbon. The increases in soil salinity were not enough to be detrimental to crops. These results indicate that soil quality was not adversely affected by eight years under stationary high tunnels managed with conventionally or organically produced vegetable crops.

L- chicoric acid is a dominant phenolic compound in lettuce (Lactuca sativa L.) and has been shown to accumulate in response to many abiotic stresses and crop management practices. It is a potent inhibitor of human immunodeficiency virus (HIV-1) integrase needed for the replication of this virus and for the productive infection of the host cell. L- chicoric acid has been found to act synergistically in combination with anti-HIV drugs used for treating acquired immuno-deficiency disorder (AIDS). We show in this study that organic management practices increase the chicoric acid content by nearly 2-fold compared to conventional management practices while they did not have a significant effect on the overall accumulation of phenolic compounds and antioxidants. Similar increase was observed in quercetin-3-O-glucoside under organic management. In addition, pre-plant fertilization decreased the levels of many phenolic compounds including chicoric acid under organic management unlike under conventional management. However, organically managed crop without pre-plant fertilization had better growth and produced about 2.5 times higher yield and higher chicoric acid content than did the conventionally managed crop. Thus, the results show that long term organic crop management practices, but avoiding pre-plant fertilization, can significantly enhance the yield of antiretroviral agent chicoric acid in lettuce.

Sensory and chemical characteristics of organically and conventionally grown pac choi (often called bok choy) were identified and quantified during 18 days of shelf life storage. Sensory and instrumental data were correlated using partial least squares regression. Pac choi was grown in early autumn at the Research and Extension Center owned by Kansas State University located in Olathe, Kansas. Samples were refrigerated at 4 °C and evaluated at 1, 4, 9, and 18 days after storage. Sensory analysis was conducted by a trained descriptive panel and compounds were identified and quantified using a gas chromatograph / mass spectrometer. Most of the decrease in the quality of pac choi during refrigerated storage is related to a decrease of textural attributes such as crispness and moistness as well as the increase in off-flavors such as stale/refrigerator and moldy. However, differences generally were small. Most of the flavor characteristics remained constant or varied slightly. Volatiles such as heptanal, octanal, benzeneacetaldehyde, 1-octanol, and (E)-2-nonen-1-ol generally were higher in organic pac choi, but those differences did not translate into sensory differences as none were found between the organic and conventionally grown leaves at any point in the shelf life.

Genotype along with growing and management conditions can affect the content and the composition of phytochemicals in plants. Two lettuce (Lactuca sativa L.) cultivars, ‘Baronet’ and ‘Red Sails,’ were grown in an open field and high tunnels to examine the effect of growing conditions on their phytochemical content. The total phenolic concentration and antioxidant capacity of lettuce increased in response to transplanting from greenhouse to both open field and high tunnels. However, the increase was much greater when seedlings were transplanted to the open field and was more than 4 fold over the pre-transplant stage. The concentrations of two major phenolic compounds, chicoric acid and chlorogenic acid, were about 2.5–5.5 times higher in both cultivars when grown in open field than in high tunnels. Also, growing lettuce in open field resulted in a greater activation of key genes (phenylalanine ammonia-lyase, L-galactose dehydrogenase and γ-tocopherol methyl transferase) involved in the biosynthesis of phenolic compounds, ascorbic acid and α-tocopherol. ‘Red Sails’ accumulated caffeic acid 4 times as much in open field as it did in high tunnels and overall contained higher amount of phenolic compounds, especially in open field, than did Baronet. Although lettuce plants grown in open field were richer in phytochemicals, a significant reduction in biomass accumulation occurred when the lettuce plants were grown in open field compared to high tunnels regardless of cultivar. These results show that growing conditions, in addition to genotype, can significantly affect the content of many phenolic compounds in lettuce and that growing lettuce under open field can have a positive impact on its health-promoting qualities.

Growers have indicated that changes in soil quality under production in high tunnels is an important problem, but these have not yet been quantified or critically assessed in the central Great Plains of the United States. We conducted surveys of grower perceptions of soil quality in their tunnels (n = 81) and compared selected soil quality indicators (salinity and particulate organic matter carbon) under high tunnels of varying ages with those of adjacent fields at sites in Kansas, Missouri, Nebraska, and Iowa in the United States. Fourteen percent of growers surveyed considered soil quality to be a problem in their high tunnels, and there were significant correlations between grower perceptions of soil quality problems and reported observations of clod formation and surface crusting and to a lesser extent surface mineral deposition. Grower perception of soil quality and grower observation of soil characteristics were not related to high tunnel age. Soil surface salinity was elevated in some high tunnels compared with adjacent fields but was not related to time under the high tunnel. In the soil upper 5 cm, salinity in fields did not exceed 2 dS·m−1 and was less than 2 dS·m−1 under 74% of high tunnels and less than 4 dS·m−1 in 97% of high tunnels. The particulate organic matter carbon fraction was higher in high tunnels than adjacent fields at 73% of locations sampled. Particulate organic matter carbon measured 0.11 to 0.67 g particulate organic matter per g of the total carbon under high tunnels sampled. Particulate organic matter carbon in the soil was also not correlated to age of high tunnel. Soil quality as measured in this study was not negatively impacted by use of high tunnel structures over time.

A survey was conducted of 81 growers managing 185 high tunnels in Missouri, Kansas, Nebraska, and Iowa to collect information about their high tunnel management practices. The survey was administered from 2005 to 2007 using internet-based and written forms. The average respondent had 4 years of high tunnel experience. The oldest tunnel still in use was 15 years old. Twenty-five percent of respondents grew crops in their high tunnels year-round. Tomato (Solanum lycopersicum), lettuce (Lactuca sativa), spinach (Spinacia oleracea), cucumber (Cucumis sativus), pepper (Capsicum spp.), leafy greens, and flowers were the most common crops. Organic soil amendments were used exclusively by 35% of growers, and in combination with conventional fertilizers by an additional 50% of growers. The summary of management practices is of interest to growers and the industries and university research and extension scientists who serve them. Growers typically reported satisfaction with their high tunnels. Growers with more than one high tunnel had often added tunnels following the success of crop production in an initial tunnel. Labor for crop maintenance was the main limiting factor reported by growers as preventing expanded high tunnel production.

ADDITIONAL INDEX WORDS. antioxidants, Lactuca sativa, phenolic compounds, vitamins ABSTRACT. In a growth chamber study, lettuce (Lactuca sativa) plants were used to evaluate the effects of water deficits on health-promoting phytochemicals with antioxidant properties. Lettuce plants were treated with water stress by withholding water once at 6weeksafter sowing for 2daysor multipletimes at 4weeksfor 4days, at5weeks for3 days, and at 6 weeks for 2 days. Water stress increased the total phenolic concentration and antioxidant capacity in lettuce. Young seedlings, 7 days after germination, had the highest total phenolic concentration and antioxidant capacity, and also, younger plants were typically more responsive to water stress treatments in accumulating the antioxidants than older plants. Phenylalanine ammonia lyase and g-tocopherol methyltransferase genes, involved in the biosynthesis of phenolic compounds and vitamin E, respectively, were activated in response to water stress, although no activation of L-galactose dehydrogenase was detected. Lettuce plants subjected to multiple water stress treatments accumulated significant amounts of chicoric acid compared with the control plants. Although the increase in antioxidant activity in water stress-treated plants at harvest was not as great as in young seedlings, it was significantly higher than the control. One-time water stress treatment of lettuce at the time of harvest did not result in any adverse effect on plant growth. Thus, these results show that mild water stress in lettuce applied just before harvest can enhance its crop quality with regard to its phytochemical concentration without any significant adverse effect on its growth or yield.

This study was conducted to identify and quantify the sensory characteristics and chemical profile of organically and conventionally grown pac choi (Brassica rapa var. Mei Qing Choi), also called bok choy, at 3 stages of growth (2.5, 4.5, and 6.5 wk). Sensory and instrumental data were correlated using partial least squares regression. Pac choi was grown in late spring. Descriptive sensory analysis was conducted by a highly trained panel and compounds were identified and quantified using a gas chromatograph/mass spectrometer. The findings of the study indicate that the differences in sensory characteristics and chemical profiles among stages of growth are more substantial than the differences between organic and conventional production. Green-unripe, musty/earthy, lettuce, and sweet flavors are representative in pac choi at early stages of growth. When older, pac choi has higher intensities of green-grassy/leafy, bitter, cabbage, and sulfur flavors that are associated with the increase of (Z)-3-hexen-1-ol, octyl acetate, 1-nonanol, 2-decanone, 1-penten-3-ol, linalool, camphor, menthol, isobornyl acetate, geranylacetone, and cedrol compounds. Conventional pac choi was higher than organic pac choi in green overall, bitter, and soapy flavors only at 2.5 wk of age. This may be associated with the presence of (Z)-3-hexenal, 2-hexyn-1-ol, and (E)-2-hexenal compounds. Practical Application: The increased popularity of organic production has amplified the need for research that will help in understanding how this production system affects the final quality of food products. This study suggests that the stage of development has a much larger impact on sensory quality than organic or conventional growing of pac choi. Findings from this study promote consumer choice by showing that comparable sensory quality can be obtained using either production system, making the ultimate choice not only based on sensory quality but consumer choice related to environmental beliefs or economics.

BACKGROUND: The increased popularity of organic production has amplified the need for research that will help in understanding how this production system affects the final quality of vegetables. The effects of organic and conventional production on the sensory characteristics of pac choi (often called bok choy) and tomato were studied. Samples were grown in high tunnel and field environments at the Kansas State University Horticulture Research Center located in Olathe, Kansas. Highly trained descriptive panelists from the Sensory Analysis Center at Kansas State University used previously developed flavor lexicons for tomatoes and leafy greens to evaluate the samples. RESULTS: ANOVA at a 95% confidence level was used to detect significant differences between treatments for individual attributes. Crispness, green-grassy/leafy, piney, and pungent attributes were normally higher in conventional pac choi only for the field samples. Pac choi grown in high tunnels showed slight differences only at individual amounts of fertilizer. Organic tomatoes grown in the field were generally juicier and less mealy compared to conventionally grown tomatoes. In the high tunnel, organic tomatoes were generally stronger in the characteristic tomato aroma. However, all differences generally were very small. CONCLUSION: It can be concluded that organic and conventional production systems do not create major sensory differences in the vegetables evaluated. The few differences that do exist are so small they may not be of practical importance. Copyright © 2010 Society of Chemical Industry

Plants typically respond to environmental stresses by inducing antioxidants as a defense mechanism. As a number of these are also phytochemicals with health-promoting qualities in the human diet, we have used mild environmental stresses to enhance the phytochemical content of lettuce, a common leafy vegetable. Five-week-old lettuce (Lactuca sativa L.) plants grown in growth chambers were exposed to mild stresses such as heat shock (40 � C for 10 min), chilling (4 � C for 1 d) or high light intensity (800 mmol m � 2 s �1 for 1 d). In response to these stresses, there was a two to threefold increase in the total phenolic content and a significant increase in the antioxidant capacity. The concentrations of two major phenolic compounds in lettuce, chicoric acid and chlorogenic acid, increased significantly in response to all the stresses. Quercetin-3-O-glucoside and luteolin-7-O-glucoside were not detected in the control plants, but showed marked accumulations following the stress treatments. The results suggest that certain phenolic compounds can be induced in lettuce by environmental stresses. Of all the stress treatments, high light produced the greatest accumulation of phenolic compounds, especially following the stress treatments during the recovery. In addition, key genes such as phenylalanine ammonia-lyase (PAL), L-galactose dehydrogenase (L-GalDH), and g-tocopherol methyltransferase (g-TMT) involved in the biosynthesis of phenolic compounds, ascorbic acid, and a-tocopherol, respectively, were rapidly activated by chilling stress while heat shock and high light did not appear to have an effect on the expression of PAL and g-TMT. However, L-GalDH was consistently activated in response to all the stresses. The results also show that these mild environmental stresses had no adverse effects on the overall growth of lettuce, suggesting that it is possible to use mild environmental stresses to successfully improve the phytochemical content and hence the health-promoting quality of lettuce with little or no adverse effect on its growth or yield. Published by Elsevier Masson SAS.

BACKGROUND: Field and greenhouse studies were performed to investigate whether organic production methods influenced levels of phenolic acid compounds in pac choi (Brassica rapa L. chinensis cv. Mei Qing Choi) compared with conventional cultivation. RESULTS: In the field experiment, organic fertilisation (compost + fish emulsion) resulted in significantly higher phenolic concentrations compared with conventional fertilisation (NPK + CaNO3) under both high tunnel and open field environments. Increased phenolics were accompanied by a significant reduction in plant fresh weight and dry weight, probably due to nitrogen deficiency. However, the elevated level of phenolics in organically grown pac choi could also have been due to confounding effects of nitrogen availability, insect attack and pesticide application. A follow-up greenhouse experiment further demonstrated a significant increase in phenolic compounds and a reduction in yield with organic fertiliser (vermicompost + fish fertiliser) relative to conventional treatment (slow release inorganic fertiliser). Preventive insecticide application did not affect the phenolic levels in pac choi under either organic or conventional fertilisation. CONCLUSION: Given that higher phenolic content in pac choi was associated with low nitrogen availability and considerable yield reduction, research is needed to determine the extent to which phenolic compounds may differ in organic and conventional pac choi when nutrient levels are adjusted to produce comparable yields. Additional study is also warranted to determine the extent to which insect attack might contribute to elevated phenolic content in organic pac choi. Copyright © 2009 Society of Chemical Industry

Microbial tea from a commercial source and a homemade manure tea were evaluated for 2 years under organic and conventional fertility regimens. Testing with different fertility regimens allowed broader assessment of tea efficacy. Collard green (Brassica oleracea L. var. acephala cv. Top Bunch) yield and soil microbial activity were measured after microbial tea applications were made in three fertility treatments (conventional, organic, or no fertilizer amendment) on a previously unfertilized sandy loam soil. Spinach (Spinacia oleracea L. cv. Hellcat) and collard green yields were determined after commercial microbial tea application to a silt loam soil previously managed with organic or conventional vegetable crops in open fields and under high tunnels. Results indicated that nutrient additions influenced crop yields, even doubling yield. This demonstrated that improved nutrient availability would affect yield at the chosen locations. However, microbial tea applications did not affect crop yield. These results did not support the hypothesis that microbial tea improves plant nutrient uptake. Additionally, soil microbial respiration and biomass were unaffected after two or three tea applications.

High tunnels are becoming an increasingly important production tool for vegetable, small fruit, and cut flower growers in many parts of the United States. They provide a protected environment relative to the open field, allowing for earlier or later production of many crops, and they typically improve yield and quality as well as disease and pest management. Producers, ranging from small-scale market gardens to larger scale farms, are using high tunnels of various forms to produce for early markets, schedule production through extended seasons, grow specialty crops that require some environmental modification, and capture premium prices. The rapid ongoing adoption of high tunnels has resulted in numerous grower innovations and increased university research and extension programming to serve grower needs. An informal survey of extension specialists was conducted in 2007 to estimate numbers (area) of high tunnels and crops being grown in them by state, and to identify current research and extension efforts. Results of this survey provide an indication of the increasing importance of these structures for horticultural crop production across the country.

BACKGROUND: This study was conducted to evaluate the influences of protected environment, organic fertilisation and growth stage on the oxygen radical absorbance capacity (ORAC) values of leafy vegetables. RESULTS: In a first experiment, pac choi grown in high tunnels had significantly lower ORAC than field-grown plants. Organic fertiliser markedly increased the antioxidant capacity of pac choi compared with conventional treatment, especially in the open field. However, both open field and organic production resulted in significantly lower yield and more severe leaf damage due to insect attack. In a second study, spinach showed the highest ORAC, followed by pac choi, red leaf lettuce and romaine lettuce. A significant decline in ORAC under high tunnel production was observed only in spinach. In contrast to the first trial, organic fertilisation did not cause an increase in antioxidant capacity of the leafy vegetables. The ORAC values of spinach from the open field and pac choi from high tunnels were significantly higher when harvested at the mature head stage than at the baby size stage. CONCLUSION: Further studies will help to elucidate effects of genotype, growth stage, and production environment on antioxidant capacities of vegetables and may lead to recommended practices to maximise antioxidant capacity of vegetable crops. Copyright © 2007 Society of Chemical Industry

The International Potato Center (known by its Spanish acronym CIP) is a research-for-development organization with a focus on potato, sweetpotato, and Andean roots and tubers. CIP is dedicated to delivering sustainable science-based solutions to the pressing world issues of hunger, poverty, gender equity, climate change and the preservation of our Earth’s fragile biodiversity and natural resources. www.cipotato.org

Plant growth, yield, and fruit quality of two strawberries (Fragaria ×ananassa Duch.)—`Chandler' and `Sweet Charlie'—grown under high tunnels (HTs) were compared with that of field plants during 2002–03 and 2003–04 growing seasons. Plug plants were planted in mid-October 2002 and mid-September 2003 on raised beds covered with black polyethylene mulch. Microclimate of the HTs protected strawberry crowns from winter damage and advanced fruit production 5 weeks earlier than that of plants grown under field conditions. From December to February, average minimum and maximum crown temperatures under the HTs were 5 and 12 °C warmer than those of the field crowns, respectively. The earliest HT fruit were harvested on 7 Apr. 2003 and 11 Mar. 2004. Yield and fruit quality under the HTs were superior to that of field-grown plants. HT plants, especially `Sweet Charlie', bloomed earlier than did field plants, but `Chandler' produced higher yield than `Sweet Charlie' late in the season. Larger fruit with higher soluble solids concentration (SSC) were produced inside the HTs than outside. HT `Sweet Charlie' fruit were sweeter than `Chandler' fruit, but `Chandler' produced larger fruit. Larger leaf area, greater number of leaves and shoot biomass, more branch-crowns, and fewer runners were developed under HTs than field conditions. Total leaf area, leaf production, total shoot biomass, and number of branch-crowns of HT `Chandler' were greater than HT `Sweet Charlie'. Results of this study indicate that strawberry plants under HTs were not only precocious, but also produced higher yields and superior quality to that of field plants. HT conditions suppressed runner growth, but enhanced branch-crown development.