Crop domestication relaxes both top-down and bottom-up effects on a specialist herbivore

Domestication of crop plants selects for numerous traits that often distinguish them dramatically from their wild progenitors. In some cases, these modifications lead to increased herbivory, by enhancing their attractiveness to herbivorous insects or reducing the efficiency of natural enemies, or both. This study investigated the effects of fruit enlargement on the olive (Olea europaea L.), the specialist olive fruit fly, Bactrocera oleae (Rossi), and its specialized larval parasitoids. Wild olive fruit are small (<2 mm pulp thickness) and the larval parasitoids associated with B. oleae have short ovipositors (<3 mm), while cultivated fruit are larger (4–8 mm pulp thickness). Female flies allocate more offspring to large than to small fruit within or across different-sized commercial cultivars, without reducing the fitness of their offspring. Fly larvae move deeper into the olive pulp with their increasing age and fruit size. In contrast, the specialist larval parasitoid, Psyttalia lounsburyi (Silvestri), more effectively parasitizes hosts in smaller than larger fruit. The inverse relationship between the performance of the fly and its co-evolved parasitoids on fruit of increasing sizes indicates that olive cultivation favors the success of the fly by providing a better food resource and more enemy-free space. These findings offer some explanation for the failure of the decades-old classical biological efforts to manage B. oleae using specialized larval parasitoids in the Mediterranean Basin and provide further evidence that crop domestication can alter host–parasitoid interactions.     

In Vivo Biochemical and Gene Expression Analyses of the Antioxidant Activities and Hypocholesterolaemic Properties of Tamarindus indica Fruit Pulp Extract

Background

Tamarindus indica (T. indica) is a medicinal plant with many biological activities including anti-diabetic, hypolipidaemic and anti-bacterial activities. A recent study demonstrated the hypolipidaemic effect of T. indica fruit pulp in hamsters. However, the biochemical and molecular mechanisms responsible for these effects have not been fully elucidated. Hence, the aims of this study were to evaluate the antioxidant activities and potential hypocholesterolaemic properties of T. indica, using in vitro and in vivo approaches.

Methodology/Principal Findings

The in vitro study demonstrated that T. indica fruit pulp had significant amount of phenolic (244.9±10.1 mg GAE/extract) and flavonoid (93.9±2.6 mg RE/g extract) content and possessed antioxidant activities. In the in vivo study, hamsters fed with high-cholesterol diet for ten weeks showed elevated serum triglyceride, total cholesterol, HDL-C and LDL-C levels. Administration of T. indica fruit pulp to hypercholesterolaemic hamsters significantly lowered serum triglyceride, total cholesterol and LDL-C levels but had no effect on the HDL-C level. The lipid-lowering effect was accompanied with significant increase in the expression of Apo A1, Abcg5 and LDL receptor genes and significant decrease in the expression of HMG-CoA reductase and Mtp genes. Administration of T. indica fruit pulp to hypercholesterolaemic hamsters also protected against oxidative damage by increasing hepatic antioxidant enzymes, antioxidant activities and preventing hepatic lipid peroxidation.

Conclusion/Significance

It is postulated that tamarind fruit pulp exerts its hypocholesterolaemic effect by increasing cholesterol efflux, enhancing LDL-C uptake and clearance, suppressing triglyceride accumulation and inhibiting cholesterol biosynthesis. T. indica fruit pulp has potential antioxidative effects and is potentially protective against diet-induced hypercholesterolaemia.     

Path analysis in fruits of the buriti (<Emphasis Type="Italic">Mauritia flexuosa</Emphasis> L. f) in populations from the Brazilian Middle North Region

The Mauritia flexuosa L.f. tree is of immense socioeconomic significance in the Brazilian Middle North Region for its manifold benefits, but mainly for its fruit. However, the potential of this species has still not been extensively studied. The objectives of this work were to study the phenotypic and genotypic correlations between the characteristics of the M. flexuosa fruits and to establish the direct and indirect effects of the secondary characteristics of the fruit on the pulp yield. Samples of ten fruits per genotype were gathered from four natural populations, from 240 different genotypes. These samples were assessed in terms of the fruit, almond and hull weights, equatorial and polar fruit diameters, and the fruit, almond and pulp, volumes, as well as the pulp yield. The genotypic correlations showed greater magnitude, higher than the phenotypic correlations, and both were significant and revealed equal signs. The indirect selection of the M. flexuosa genotypes with greater fruit weight and almond volume favored the increase in the pulp yield in this fruit species.     

Analysis of Papaya Cell Wall-Related Genes during Fruit Ripening Indicates a Central Role of Polygalacturonases during Pulp Softening

Papaya (Carica papaya L.) is a climacteric fleshy fruit that undergoes dramatic changes during ripening, most noticeably a severe pulp softening. However, little is known regarding the genetics of the cell wall metabolism in papayas. The present work describes the identification and characterization of genes related to pulp softening. We used gene expression profiling to analyze the correlations and co-expression networks of cell wall-related genes, and the results suggest that papaya pulp softening is accomplished by the interactions of multiple glycoside hydrolases. The polygalacturonase cpPG1 appeared to play a central role in the network and was further studied. The transient expression of cpPG1 in papaya results in pulp softening and leaf necrosis in the absence of ethylene action and confirms its role in papaya fruit ripening.     

A comparative study of biological potentiality and EAC cell growth inhibition activity of Phyllanthus acidus (L.) fruit pulp and seed in Bangladesh

Medicinal plant-derived bioactive compounds have recently gained more interest in biological research as an important source of novel drug candidates. Phyllanthus acidus (L.) is a widely distributed herbal medicinal plant naturally used in Ayurvedic medicine in Bangladesh. The present study focused on exploring the biological potential as well as the inhibitory effect of EAC cell growth with a comparative analysis between Phyllanthus acidus fruit pulp and seed. Crude methanol extract of P. acidus (MEPA) fruit pulp and seed was assessed as DPPH and NO free radical scavengers. While Brine Shrimp lethality bioassay, the standard protocol of phytochemical screening and hemagglutination assay were performed successively to determine the toxic effect on normal cells, the identification of some crucial phytochemicals, and the existence of lectin protein. EAC (Ehrlich’s Ascites Carcinoma) cell growth inhibition was determined by hemocytometer and morphological changes of EAC cells were observed by a fluorescence microscope using Swiss albino mice. The IC₅₀ value of MEPA fruit pulp and seed was obtained as 57.159 µg/ml and 288.743 µg/ml respectively where minimal toxic effects on Brine Shrimp nauplii demonstrates that it is a good source of natural antioxidant compounds. Again, MEPA fruit pulp and seed-mediated effective agglutination of mouse blood erythrocyte strongly support the presence of lectin protein. Furthermore, MEPA fruit pulp and seed extract-treated EAC cells showed 65.71% and 28.57% growth inhibition respectively. The fluorescent microscopic examination of EAC cells treated with MEPA fruit pulp has shown more remarkable structural changes in the nucleus than that of seed. Based on the above findings, the present study reveals that MEPA fruit pulp can be considered as a novel biological candidate for the treatment of fatal diseases shortly.     

Role of Brassinosteroids, Ethylene, Abscisic Acid, and Indole-3-Acetic Acid in Mango Fruit Ripening

Rapid ripening of mango fruit limits its distribution to distant markets. To better understand and perhaps manipulate this process, we investigated the role of plant hormones in modulating climacteric ripening of ??Kensington Pride?? mango fruits. Changes in endogenous levels of brassinosteroids (BRs), abscisic acid (ABA), indole-3-acetic acid (IAA), and ethylene and the respiration rate, pulp firmness, and skin color were determined at 2-day intervals during an 8-day ripening period at ambient temperature (21?±?1°C). We also investigated the effects of exogenously applied epibrassinolide (Epi-BL), (+)-cis, trans-abscisic acid (ABA), and an inhibitor of ABA biosynthesis, nordihydroguaiaretic acid (NDGA), on fruit-ripening parameters such as respiration, ethylene production, fruit softening, and color. Climacteric ethylene production and the respiration peak occurred on the fourth day of ripening. Castasterone and brassinolide were present in only trace amounts in fruit pulp throughout the ripening period. However, the exogenous application of Epi-BL (45 and 60?ng?g^?1 FW) advanced the onset of the climacteric peaks of ethylene production and respiration rate by 2 and 1?day, respectively, and accelerated fruit color development and softening during the fruit-ripening period. The endogenous level of ABA rose during the climacteric rise stage on the second day of ripening and peaked on the fourth day of ripening. Exogenous ABA promoted fruit color development and softening during ripening compared with the control and the trend was reversed in NDGA-treated fruit. The endogenous IAA level in the fruit pulp was higher during the preclimacteric minimum stage and declined during the climacteric and postclimacteric stages. We speculate that higher levels of endogenous IAA in fruit pulp during the preclimacteric stage and the accumulation of ABA prior to the climacteric stage might switch on ethylene production that triggers fruit ripening. Whilst exogenous Epi-BL promoted fruit ripening, endogenous measurements suggest that changes in BRs levels are unlikely to modulate mango fruit ripening.     

Tissue compartmentation of phenylpropanoid metabolism in tomatoes during growth and maturation

Marked changes in the metabolism of hydroxycinnamic acid derivatives were observed in pulp and pericarp of tomato fruit (Lycopersicon esculentum var. cerasiforme) during its development. During fruit growth, biosynthesis and accumulation of chlorogenic acid were especially active in the pulp, whereas the formation of glucose derivatives occurred during maturation in the pericarp. There was a clear difference between the two compartments of the fruit concerning hydroxycinnamate: CoA ligase, O-methyltransferase and glucosyltransferase activities. The first two enzymes were high in the pulp during growth and the latter one was high in the pericarp during maturation. Of all the enzymes studied, only the glucosyltransferase showed increasing activity during maturation; it may be considered, along with the glucosylated derivatives, as a biochemical marker of maturation in tomato.     

Postharvest disease management of Alternaria spots on tomato fruit by Annona muricata fruit extracts

The aim of this study was to assess Annona muricata L. fruit extracts as an alternative to synthetic fungicide against Alternaria alternata (Fries) Keissler, the causative agent of black spots of tomato fruit. Antifungal activities of A. muricata pulp and seed extracts were tested both in vitro and in vivo. The seed extracts were more potent at inhibiting A. alternata than the pulp extracts. The in vitro assay showed maximum inhibition of radial mycelial growth of A. alternata (90%) by methanol seed extracts, at the highest concentration of 6%. Similarly, the in vivo assay showed marked reduction in lesion diameter (2.1 mm) and consequent disease inhibition (84%) on the tomato fruit treated with methanol seed extracts. Scanning electron microscopy showed that A. muricata extracts significantly damaged the morphology of hyphae and conidial structures. The FT-IR spectrum obtained from methanol extracts showed bands representing important bioactive compounds that possess antifungal activity. Based on our findings, Annona muricata fruit extracts can be further explored as a potential, excellent alternative approach to control the postharvest Alternaria spots of tomato fruit.     

Quinic acid esters of hydroxycinnamic acids in stone and pome fruit

In 21 varieties of stone and pome fruit the quinic acid esters of caffeic, p-coumaric and ferulic acids have been determined by capillary GC and HPLC. The total content of hydroxycinnamoylquinic acids was found to be between 80 and almost 900 ppm fr. wt. The results confirm that the main hydroxycinnamic acid compound in pome fruit is 5′-caffeoylquinic acid, whereas in stone fruit it is 3′-caffeoylquinic acid. Our investigations also show the regular occurrence of 3′-p-coumaroylquinic acid in stone fruit species. In sweet and sour cherries it can be the main component in concentrations of 100–200 ppm. Significant amounts of feruloylquinic acid are only found in plums and apricots. The 4′-isomers of all acids occur only in very small concentrations with the exception of 4′-p-coumaroylquinic acid in apples, the content of which exceeds that of 5′-p-coumaroylquinic acid.     

Polysaccharides from the pulp of cupuassu (Theobroma grandiflorum): Structural characterization of a pectic fraction

Cupuassu (Theobroma grandiflorum, Schumann) is a Brazilian Amazonian fruit whose pulp contains volatile compounds that have been extensively studied. In this work, the pulp from fruits of cupuassu was ground, treated with MeOH–H₂O, and defatted with p-Tol–EtOH. The residue (4% in relation to the fresh pulp) was submitted to sequential extractions with water, aqueous citric acid and aqueous NaOH, resulting in polysaccharide fractions with 0.3–15% yield. The main pectic fraction (7% yield) was obtained with water at 25 °C (W-1 fraction) and was chosen to be better characterized. Chemical and spectroscopic analyses showed that W-1 is composed mainly of a homogalacturonan highly esterified (DE 53%; DA 1.7%) with some rhamnogalacturonan insertions, carrying side chains containing galactose and arabinose.     

Signal and reward in wild fleshy fruits: Does fruit scent predict nutrient content?

相似文献   

Friend or foe? Disparate plant–animal interactions of two congeneric rodents

Food and water resources are limiting factors for animals in desert ecosystems. Fleshy fruits are a rare water source in deserts and when available they tend to attract a wide variety of organisms. Here we show that two congeneric rodent species, Acomys cahirinus and A. russatus, employ different fruit eating strategies that result in either dispersal or predation of the small seeds of the desert plant Ochradenus baccatus. The nocturnal A. cahirinus leaves intact seeds when consuming O. baccatus fruits and thus, acts mainly as a seed disperser; whereas the diurnal A. russatus consumes the whole fruit and digests the seeds and thus, acts mainly as a seed predator. Acomys russatus is subjected to the toxic products of the glucosinolates-myrosinase system found in O. baccatus fruits. Acomys cahirinus avoids the toxic compounds by consuming the pulp only, which contains glucosinolates but not the seeds that contain the enzyme that activates them. We suggest that the behavioral responses exhibited by A. russatus are the result of physiological adaptations to whole fruit consumption that are absent in A. cahirinus. Our results shed new light on the ecological divergence of the two congeneric species.     

Carotenoids in pulp,peel and leaves of Persea americana

A complex pattern of chloroplast pigments was found to be common to pulp, peel and leaves of avocado. This is explained by the presence of chlorophyll in the ripe fruit and its peel. Two chromoplast-specific pigments were found in ripe pulp and are tentatively identified as α-citraurin and mimulaxanthin. The identity of the latter and of neochrome, was established inter alia by the MS. The xanthophylls occur esterified to a major extent in pulp but entirely free in peel. The coexistence of chloroplast and chromoplast pigments in avocado fruit make this a suitable object for the ultrastructural studies of the origin of the chromoplasts.     

Carbohydrate metabolism in Musa paradisiaca

Considerable variations exist in the content of glucose, fructose, sucrose, starch and protein and in the activities of enzymes involved in carbohydrate metabolism between different parts of the banana plant (Musa paradisiaca). Sucrose synthetase is present in the highest concentration in rootstock and fruit pulp, and sucrose phosphate synthetase in the pseudostem. The highest ratio of the activity of sucrose phosphate synthetase to sucrose synthetase is found in leaves. Acid invertase is present in leaves, leaf-sheath and fruit pulp and is not demonstrable in rootstock and pseudostem. Neutral invertase activity is high in pseudostem and leaf-sheath. Starch phosphorylase is largely concentrated in fruit pulp and rootstock. The maximum activity of ATP:d-phosphoglucose (ADPG) pyrophosphorylase is found in rootstock. β-Amylase is not demonstrable in rootstock and is largely concentrated in leaf-sheath. Hexokinase is most active in rootstock and the lowest in leaves. Acid phosphatase and alkaline phosphatase activity is highest in fruit pulp and pseudostem. Glucosephosphate isomerase is most active in the rootstock and lowest in the leaves.     

Volatile constituents and fatty acid composition of lipids in Durio zibethinus

The predominating flavour compounds in the fruit pulp of Durio zibethinus were hydrogen sulfide, ethyl hydrodisulfide and several dialkyl polysulfides, particularly (C₂H₅)₂S_n, where n = 2 or 3. Ethyl acetate, 1,1-diethoxyethane and ethyl 2-methylbutanoate contribute to an additional fruity odour note. Hydrodisulfides are probably the precursors of the dialkyl sulfides. In the pericarp and seed no volatile sulfur compounds could be detected. The fatty acid composition of the lipids in pericarp, pulp and seed depended on the origin and/or harvest season of the fruit. The main components were oleic and palmitic acids or arachidic acid together with appreciable quantities of palmitoleic, stearic, linoleic and linolenic acids.     

Structure and development of the style base in Abildgaardia, Bulbostylis, and Fimbristylis (Cyperaceae,Cyperoideae, Abildgaardieae)

The Abildgaardieae tribe within the family Cyperaceae comprises six or seven genera, among which Abildgaardia, Bulbostylis and Fimbristylis pose a challenge regarding their morphological delimitation. Molecular phylogenetic analyses including species of Abildgaardieae are rare, but in most of those studies, Abildgaardia and Fimbristylis appear as more closely related to each other than to the Bulbostylis genus. Duration of the style base has been one of the most widely used characters for delimiting these three genera. The style base is a persistent structure in most species of Bulbostylis and deciduous in Abildgaardia and Fimbristylis. The reasons why the style base may persist or fall off have been scarcely discussed. The assumption that abscission layers are present in the style base of all three genera and the fact that tracheids have been observed in the style base of Bulbostylis suggest that this structure might have histological complexity. In view of this, a complete ontogenetic and anatomical study of the gynoecium has been carried out for all these three genera. It turned out that the style base is histologically simple in Abildgaardia, Bulbostylis and Fimbristylis and shows similar structure and development in all three genera. The fact that the style base has a shorter duration in Abildgaardia and Fimbristylis than in Bulbostylis might be related to the lower number of sclerotised cells that make up such structures in the mature fruit of the former two genera. Abscission of the style and style base may be the result of much simpler reasons than the differentiation of an abscission layer, resulting merely from mechanical shear force effects. Differences among genera have been observed in the shape of the style base and the development of the style. The histological simplicity of the style base is consistent with the homoplastic appearance of this structure in genera that are not closely related (e.g. Rhynchospora). Because of this, while the presence of the thickened style base seems to be a synapomorphy in species of Abildgaardieae, its persistence on or detachment from the fruit might have emerged repeatedly during this clade evolution and might not be a suitable character for genera delimitation.