Publications by authors named "Robert Paull"

Breadfruit (Artocarpus altilis (Parkinson) Fosberg) is a prolific tropical tree producing highly nutritious and voluminous carbohydrate-rich fruits. Already recognized as an underutilized crop of high potential, breadfruit could ameliorate food insecurity and protect against climate-related productivity shocks in undernourished equatorial regions. However, a lack of fundamental knowledge impedes widespread agricultural adoption, from modern agroforestry to plantation schemes.

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Pineapple () and ornamental bromeliads are commercially induced to flower by treatment with ethylene or its analogs. The apex is transformed from a vegetative to a floral meristem and shows morphological changes in 8 to 10 days, with flowers developing 8 to 10 weeks later. During eight sampling stages ranging from 6 h to 8 days after treatment, 7961 genes were found to exhibit differential expression (DE) after the application of ethylene.

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Calcium oxalate raphide crystals are found in bundles in intravacuolar membrane chambers of specialized idioblasts cells of most plant families. Aroid raphides are proposed to cause acridity in crops such as taro ( (L.) Schott).

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Article Synopsis
  • * Comparative analysis showed the genomes of transgenic SunUp and its parent Sunset are nearly identical, with key insertions and translocations found on chromosome 5.
  • * Research highlighted the importance of specific genes in carotenoid production during domestication and contributed to a better understanding of sex chromosomes and their effects on papaya breeding and improvement efforts.
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Natural flowering affects fruit development and quality, and impacts the harvest of specialty plants like pineapple. Pineapple growers use chemicals to induce flowering so that most plants within a field produce fruit of high quality that is ready to harvest at the same time. Since pineapple is hand-harvested, the ability to harvest all of the fruit of a field in a single pass is critical to reduce field losses, costs, and waste, and to maximize efficiency.

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Article Synopsis
  • Researchers sequenced the genome of the pineapple variety Ananas comosus var. bracteatus CB5, revealing insights into its genetic structure with 29,412 identified genes across 25 chromosomes.
  • The study compared multiple pineapple genomes and revealed specific genetic traits related to fiber production, sugar accumulation, and fruit maturation, confirming varied domestication processes across cultivars.
  • The findings indicate a blend of sexual and asexual reproduction in the domestication of clonally propagated crops, encouraging further investigation into these processes for other similar species.
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Pineapple (Ananas comosus (L.) Merr.) is the most economically valuable crop possessing crassulacean acid metabolism (CAM), a photosynthetic carbon assimilation pathway with high water-use efficiency, and the second most important tropical fruit.

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Premise Of The Study: Floral nectar sugar compositions have, for several decades, been used to predict a plant species' pollinator guild. Plants possessing a generalist ornithophilous pollination syndrome produce nectar that is dilute (8-12% w/v sugars) with a low sucrose to hexose (glucose and fructose) ratio. The Hawaiian lobeliad genus Clermontia contains 22 endemic species of shrubs and small trees that are believed to have evolved flowers adapted for pollination by now mostly extinct or endangered endemic passerines in the Drepanidinae and Mohoidae.

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Background: Sacred lotus is a basal eudicot with agricultural, medicinal, cultural and religious importance. It was domesticated in Asia about 7,000 years ago, and cultivated for its rhizomes and seeds as a food crop. It is particularly noted for its 1,300-year seed longevity and exceptional water repellency, known as the lotus effect.

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The draft genome of the pear (Pyrus bretschneideri) using a combination of BAC-by-BAC and next-generation sequencing is reported. A 512.0-Mb sequence corresponding to 97.

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Papaya is a model system for the study of sex chromosome evolution in plants. However, the cytological structures of the papaya chromosomes remain largely unknown and chromosomal features have not been linked with any genetic or genomic data. We constructed a cytogenetic map of the papaya sex chromosome (chromosome 1) by hybridizing 16 microsatellite markers and 2 cytological feature-associated markers on pachytene chromosomes using fluorescence in situ hybridization (FISH).

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Heteroxylans in the plant cell wall have been proposed to have a role analogous to that of xyloglucans or heteromannans, forming growth-restraining networks by interlocking cellulose microfibrils. A xylan endotransglycosylase has been identified that can transglycosylate heteroxylan polysaccharides in the presence of xylan-derived oligosaccharides. High activity was detected in ripe fruit of papaya (Carica papaya), but activity was also found in a range of other fruits, imbibed seeds and rapidly growing seedlings of cereals.

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Carotenoid pigments in fruits are indicative of the ripening process and potential nutritional value. Papaya (Carica papaya) fruit flesh color is caused by the accumulation of lycopene or beta-carotenoids in chromoplasts. It is a distinct feature affecting nutritional composition, fruit quality, shelf life, and consumer preference.

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A high-density genetic linkage map of papaya, previously developed using an F2 mapping population derived from the intraspecific cross AU9 x SunUp, was enriched with AFLP markers. The comprehensive genetic map presented here spans 945.2 cM and covers 9 major and 5 minor linkage groups containing 712 SSR, 277 AFLP, and 1 morphological markers.

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Insects are commonly found by Hawaii's quarantine inspectors on Christmas trees imported from the Pacific Northwest. To reduce the risk of importing yellowjacket (Vespula spp.) queens and other insects, an inspection and tree shaking certification program was begun in 1990.

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Papaya, a fruit crop cultivated in tropical and subtropical regions, is known for its nutritional benefits and medicinal applications. Here we report a 3x draft genome sequence of 'SunUp' papaya, the first commercial virus-resistant transgenic fruit tree to be sequenced. The papaya genome is three times the size of the Arabidopsis genome, but contains fewer genes, including significantly fewer disease-resistance gene analogues.

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Papaya (Carica papaya L.) cell wall matrix polysaccharides are modified as the fruit starts to soften during ripening and an endoxylanase is expressed that may play a role in the softening process. Endoxylanase gene expression, protein amount and activity were determined in papaya cultivars that differ in softening pattern and in one cultivar where softening was modified by the ethylene receptor inhibitor 1-methylcyclopropene (1-MCP).

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In the ABC model of flower development, B function organ-identity genes act in the second and third whorls of the flower to control petal and stamen identity. The trioecious papaya has male, female, and hermaphrodite flowers and is an ideal system for testing the B-class gene expression patterns in trioecious plants. We cloned papaya B-class genes, CpTM6-1, CpTM6-2, and CpPI, using MADS box gene specific degenerate primers followed by cDNA library screening and sequencing of positive clones.

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A high-density genetic map of papaya (Carica papaya L.) was constructed using microsatellite markers derived from BAC end sequences and whole-genome shot gun sequences. Fifty-four F(2) plants derived from varieties AU9 and SunUp were used for linkage mapping.

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Papaya (Carica papaya L.) softening during fruit ripening is correlated with the activities of an endoxylanase (EC 3.2.

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