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1.
Effects of hot water treatment (HWT; 53 °C for 2 min) and Pichia membranaefaciens, either alone or in combination, on controlling Penicillium italicum, Penicillium digitatum, and natural infection in citrus fruit were investigated. Results showed that the combined treatment significantly reduced disease incidence and lesion diameters of blue and green molds in artificially inoculated fruit whether the pathogens were inoculated after or before the treatment compared with the treatment of P. membranaefaciens or HWT alone. The combination of P. membranaefaciens with HWT was as effective as the fungicide treatment in natural infection trials. Application of HWT did not affect the growth of P. membranaefaciens in the wounds of citrus fruit at 20 °C or 4 °C. P. membranaefaciens combined with HWT effectively enhanced the phenylalanine ammonia-lyase, peroxidase, polyphenoloxidase, chitinase, and β-1,3-glucanase activities and stimulated the synthesis of phenolic compounds. These results suggest that the use of HWT is a useful approach to improve the efficacy of P. membranaefaciens in postharvest diseases of citrus fruit.  相似文献   

2.
Hulless barley breeding lines varying in amylose (1–20% DM) and β-glucan content (5–10% DM) have been developed at the Crop Development Centre, Canada. The objectives of this large-scale study were to 1) determine and confirm the effect of these new hulless barley lines (zero-amylose waxy, CDC Fibar; 5%-amylose waxy, CDC Rattan; normal-amylose, CDC McGwire and high-amylose, HB08302) with altered carbohydrate traits on 1) metabolic characteristics of protein; 2) intestinal digestion of various nutrients and 3) modeling nutrient supply from these barley varieties by using NRC Dairy 2001 model and DVE/OEB system. CDC Copeland was included as a hulled barley control. Among the hulless barley lines, CDC Fibar contained the highest and CDC McGwire contained the lowest total digestible protein (TDP: 147 vs. 116 g/kg DM). HB08302 was greater (P < 0.05) in intestinal digestible protein (IDP: 40.6% RUP) but relatively lower (P < 0.05) in total digestible protein (TDP: 120 g/kg DM). Compared with hulless barley, hulled barley showed relatively lower (P < 0.05) intestinal digestible protein (38 vs. 53 g/kg DM) and total digestible protein (102 vs. 129 g/kg DM). In modeling nutrient supply from the DVE/OEB system, the results showed hulled barley was lower (P < 0.01) in true protein supplied to the small intestine (TPSI: 127 vs. 142 g/kg DM), lower in truly absorbed rumen bypassed feed protein in small intestine (ABCPDVE: 43 vs. 58 g/kg DM), lower in truly absorbed protein in the small intestine (DVE: 95 vs. 111 g/kg DM), and lower in degraded protein balance (OEBDVE: −39 vs. −23 g/kg DM) than the hulless barley lines but greater (P < 0.01) in undigested inorganic matter (9 g/kg DM). From NRC Dairy 2001 model, CDC Fibar was greater (P < 0.05) in degraded protein balance (OEBNRC: −30 g/kg DM) and metabolizable protein (MP: 118 g/kg DM) than the other hulless barley lines, while hulled barley was relatively lower (P < 0.01) in total metabolizable protein (MP: 83 vs. 105 g/kg DM). Our correlation results suggested that TDP was negatively correlated to amylose (r = −0.85, P < 0.001) but positively correlated to β-glucan level (r = 0.74, P < 0.001) in hulless barley cultivars. The DVE and OEBDVE as well as MP were negatively correlated (P < 0.05) to amylose level but positively correlated to β-glucan level (P < 0.05). In conclusion, altered carbohydrate traits in the hulless barley varieties have the potential to increase intestinal nutrient availability to ruminants and significantly improved the truly absorbed protein supply to dairy cattle compared to hulled barley. Hulless barley with lower amylose and higher β-glucan level could provide greater (P < 0.05) truly digested protein in the small intestine, better synchronized available energy and N and increase metabolizable protein supply to ruminants.  相似文献   

3.
The Indian gypsy moth (Lymantria obfuscata) is a pest of national significance, which attacks a wide range of forest and fruit crops in India. The outbreaks of this pest over the past few years spurred interest towards sustainable biointensive approaches for quality fruit production of apple and walnut for agricultural export in Jammu & Kashmir (J & K). The exploratory survey's were conducted for the isolation of native strains of L. obfuscata multiple nucleopolyhedrovirus (LyobMNPV) and field evaluation was conducted to determine the most promising strain as a potential biological control agent of this pest. The virus was recovered from different locations of J&K with its natural incidence varying from 0.77 to 7.43 percent. This is the first report from the Indian sub-continent and worldwide of the occurrence of NPVs in natural larval populations of L. obfuscata. The in vivo mass production was optimised by inoculating per os late 3rd instar L. obfuscata larvae with an inoculum dose of 1.44 × 105 OBs/larva and followed by a 10 day incubation period. To prevent the disintegration of larval cuticle and microbial contamination, moribund larvae were harvested with an average yield of 1.42 × 108 OBs/larva. The field application of LyobMNPV against the host populations on apple and willow with the pre-standardised dosage of 2.5 × 1012 OBs/ha reduced the larval population density by 25–63%. In the year following application, the larval population density in the treated blocks was 19–28% lower as compared to controls on both apple and willow. This suggests that the virus has considerable potential as a biocontrol agent and the timely application with LyobMNPV on non-fruit trees such as willow which are the preferred hosts for egg laying may help to initiate viral epizootics to keep population outbreaks under check.  相似文献   

4.
The potential of quinoa to act as a source of dipeptidyl peptidase IV (DPP-IV) inhibitory and antioxidant peptides was studied. A quinoa protein isolate (QPI) with a purity of 40.73 ± 0.90% was prepared. The QPI was hydrolysed at 50 °C for 3 h with two enzyme preparations: papain (P) and a microbial papain-like enzyme (PL) to yield quinoa protein hydrolysates (QPHs). The hydrolysates were evaluated for their DPP-IV inhibitory and oxygen radical absorbance capacity (ORAC) activities. Protein hydrolysis was observed in the QPI control, possibly due to the activity of quinoa endogenous proteinases. The QPI control had significantly higher DPP-IV half maximal inhibitory concentrations (IC50) and lower ORAC values than QPH-P and QPH-PL (P < 0.05). Both QPH-P and QPH-PL had similar DPP-IV IC50 and ORAC values. QPH-P had a DPP-IV IC50 value of 0.88 ± 0.05 mg mL−1 and an ORAC activity of 501.60 ± 77.34 μmol Trolox equivalent (T.E.) g−1. To our understanding, this is the first study demonstrating the in vitro DPP-IV inhibitory properties of quinoa protein hydrolysates. QPHs may have potential as functional ingredients with serum glucose lowering properties.  相似文献   

5.
The tomato red spider mite, Tetranychus evansi Baker and Pritchard, is one of the most serious pests of solanaceous crops in Africa. Field experiments were conducted to investigate its effects on the growth and leaf yield of five African nightshade species viz. Solanum americanum, S. sarrachoides, S. scabrum, S. tarderemotum and S. villosum during the 2008 and 2009 growing seasons. Plants were infested with 2–4 day-old female spider mites which were allowed to multiply. The number of mite motiles increased throughout the growing season in unsprayed plots and this number varied significantly between the African nightshade species. Except for S. sarrachoides, leaf damage was high on the other four Solanum species irrespective of the spraying regime during both seasons. However, S. scabrum had a significantly greater leaf area ratio (ratio of leaf area to total plant weight) and specific leaf area (ratio of leaf area to total leaf dry weight) during both seasons. Overall yields were 1.5 times more in S. scabrum and S. sarrachoides compared to S. americanum, S. tarderemotum and S. villosum. Our results show that T. evansi infestation affects the leaf area ratio and specific leaf area of African nightshade species differentially which eventually determines the plant's overall leaf yield. These findings present an opportunity for evaluation and selection of African nightshade species that can withstand spider mite infestation in small holder farms for increased vegetable production in Africa.  相似文献   

6.
7.
Recently, the immune stimulation properties of cereal arabinoxylans (AX) have been reported. The aims of this study were to identify the molecular features and potential immune stimulation activities of AX and enzymatic modified arabinoxylan (AXE) from the pentosan fraction of wheat flour.The results of molecular characterization of AX and AXE show that AXE contains a larger portion (85.7%) of low Mw arabinoxylans (≤25 kDa) and has a higher degree of branch substitution (0.81 ± 0.01) compared to AX (49.5% and 0.62 ± 0.02). In in vitro testing, the ability of AX and AXE to stimulate immune cells, as measured by NO2 production by U937 cells and IL-8 secretion by Caco-2 cells were found to be dose–dependent in the range tested (100–5000 μg/mL p ≤ 0.05). AXE showed a greater activity at each concentration (100–5000 μg/mML) than AX (p ≤ 0.05).In conclusion, the greater immune stimulating activity of AXE may be associated with its low Mw (≤25 kDa) and a higher degree of branch substitution (0.81 ± 0.01).  相似文献   

8.
The influence of high molecular weight glutenin subunits (HMW-GS) on wheat breadmaking quality has been extensively studied but the effect of different Glu-1 alleles on cookie quality is still poorly understood. This study was conducted to analyze the effect of HMW-GS composition and wheat-rye translocations on physicochemical flour properties and cookie quality of soft wheat flours. Alleles encoded at Glu-A1, Glu-B1 and Glu-D1 locus had a significant effect over physicochemical flour properties and solvent retention capacity (SRC) profile. The null allele for Glu-A1 locus presented the highest cookie factor observed (CF = 7.10), whereas 1BL/1RS and 1AL/1RS rye translocations had a negative influence on CF. The three cultivars that showed the highest CF (19, 44 and 47) had the following combination: Glu-A1 = null, Glu-B1 = 7 + 8, Glu-D1 = 2 + 12 and no secalins. Two prediction equations were developed to estimate soft wheat CF: one using the HMW-GS composition and the other using physicochemical flour parameters, where SRCsuc, SRC carb, water-soluble pentosans, damaged starch and protein turned out to be better CF predictors. This data suggests that grain protein allelic composition and physicochemical flour properties can be useful tools in breeding programs to select soft wheat of good cookie making quality.  相似文献   

9.
The effects of biofumigation and soil heating on arbuscular mycorrhizal fungi (AMF) colonisation, strawberry growth and strawberry yield in pot experiments compared with untreated soil and chemical fumigation with dazomet were tested. Three different Brassicaceae species (Brassica juncea, Eruca sativa, Sinapis alba) were used as biofumigant plant green manure and soil heating was applied to simulate soil solarisation. Half of the plants were inoculated with indigenous arbuscular mycorrhizal fungi inoculum. With one exception (E. sativa) among the uninoculated plants, the treatments significantly decreased the mycorrhizal colonisation parameters compared with the untreated control. Dazomet displayed the greatest inhibitory effects on AMF establishment. In addition, the intensity and number of bands corresponding to Glomus spp. obtained with temporal temperature-gradient gel electrophoresis were lower for strawberry plants from biofumigant treatments than from the control. For the inoculated plants, there were almost no significant differences among the mycorrhizal colonisation parameters. The mass of leaves for the uninoculated and inoculated plants was higher for almost all non-chemical soil fumigant treatments compared with the control, except for heating of the uninoculated treatments. The number of strawberry fruits for the uninoculated biofumigant treatments was the highest, being higher than the values observed for the heating treatments, the chemical disinfection treatments and the control. There were no significant differences among the inoculated treatments. Biofumigation with Brassicaceae species resulted in higher soil organic matter and mineral nutrients and had a relatively small effect on AMF colonisation (F% = 59.0, 80.3, 47.3 for Bj, Es and Sa, respectively) compared with uninoculated controls (F% = 84.3). Despite the reduced AMF colonisation, biofumigation resulted in a higher fruit number and mass of leaves. Therefore, it represents a non-chemical soil fumigation method that should be applied in sustainable strawberry production.  相似文献   

10.
Nematode management zones (MZs) based on soil electrical conductivity (EC, a proxy for soil texture) have not been published for Rotylenchulus reniformis. We tested 1) whether R. reniformis levels and the amount of damage caused to cotton differed among MZs, 2) if the relative effectiveness of nematicides differed among MZs, and 3) whether the prevalence of Pasteuria sp. on R. reniformis differed among MZs and nematicide treatments. A field was divided into three MZs where MZ3 had sandier soil than MZ1 or MZ2, which were the same, and MZ2 had higher elevation than MZ1 or MZ3, which were the same. Levels of R. reniformis near planting in plots not receiving nematicide averaged 1342 (per 150 cm3 soil) in 2008, 610 in 2009, and 869 in 2010. Both soil texture and elevation influenced R. reniformis population levels with greater reproduction in finer-textured soil and reduced R. reniformis levels at higher elevation. Treatment effects on R. reniformis levels were the same in all MZs (no MZ × treatment interactions). The effects of texture and elevation on yield were similar to the effects on nematode levels. We observed endospores of Pasteuria sp., a bacterial parasite of nematodes, on R. reniformis at the field site used for this study. Pasteuria sp. generally had greater spore attachment to juvenile R. reniformis than to adults with no differences among MZs in percentage of nematodes with endospores, but the number of spores per nematode was lower in MZ3, which had the greatest sand content. The percentage of R. reniformis with endospores and the number of attached endospores were reduced by 1,3-dichloropropene + aldicarb. We documented that R. reniformis levels are affected by modest differences in soil texture and elevation, but levels of R. reniformis were above the action threshold in all MZs, therefore a uniform rate of nematicide would have been recommended and there would have been no cost savings from utilizing MZs in this field.  相似文献   

11.
Thirty-seven varieties of a Mediterranean durum wheat collection grown in Tunisia and Spain were analysed for their allelic composition in prolamins, as well as their protein concentration, sodium dodecyl sulphate sedimentation (SDSS) test and mixograph parameters. Genotype was a greater source of variation in all measurements than locality. Uncommon high and low molecular glutenin subunits (HMW-GS and LMW-GS) were found (V and 2•• subunits at Glu-A1, 13 + 16 at Glu-B1, 5* subunit and ax allele at Glu-A3). The rare combinations 2 + 4+14 + 18 and 8 + 9+13 + 16+18 subunits at the Glu-B3 locus were found. Glu-A3ax had a positive influence on SDSS and mixograph parameters. Of all the prolamins, those that have the B-LMW-GS composition aaa (for Glu-A3, Glu-B3 and Glu-B2 loci, respectively), when associated with the Glu-A1c and Glu-B1d gave the best semolina quality. By contrast, semolina quality is poor when this same composition is associated with the Glu-A1c and Glu-B1e and even poorer when associated with the Glu-A1c and Glu-B1f. In addition, the cultivars with B-LMW-GS allelic composition aab (for Glu-A3, Glu-B3 and Glu-B2 loci, respectively), when associated with the Glu-A1c and Glu-B1d, gave high quality, whereas when associated with the Glu-A1c and Glu-B1e or with Glu-A1o and Glu-B1f, the quality was very poor.  相似文献   

12.
The variations of the amounts of individual high molecular weight glutenin subunits (HMW-GS), of the ratios HMW-GSy to HMW-GSx and HMW-GS to low molecular weight glutenin subunits (LMW-GS) and of protein content were evaluated for eight durum wheat cultivars in two regions using four fertilizer combinations during two successive years. All measured parameters showed significant variation with genotypes (G), environments (E) and fertilizers (F). The interaction E × G × F was highly significant for glutenin amount variation. Amongst cultivars possessing HMW-GS 20, landraces seem to better value the N-fertilizer use for the accumulation of HMW-GSy than high yielding cultivars. Both HMW-GSy to HMW-GSx and HMW-GS to LMW-GS ratios were found to be positively correlated (p < 0.05) with total protein content.  相似文献   

13.
Aspergillus section Flavi is able to produce aflatoxins (AFs) in vitro down to 0.85 aw with a potential maximum occurring between 0.95 and 0.99 aw, while in the field AFs increased significantly with kernel humidity below 0.95 aw. In order to clarify this apparent discrepancy, a 3-year field trial with artificial inoculation of maize ears with Aspergillus flavus strains was organised. The co-occurrence of Aspergillus section Flavi and Gibberella fujikuroi species complex (Gfsc) was observed. The incidence of A. flavus was significantly influenced by the year and negatively related to Gfsc incidence. In 2012, when the highest temperature and the lowest rain were registered, aflatoxin B1 (AFB1) content was the highest and aw < 0.95 in kernels was measured early throughout the growing season. In 2013 and 2014, the temperature was lower and rain more abundant, and aw decreased below 0.95 only close to harvest and AFB1 contamination was limited. The possibility of describing/predicting reasonably well aw dynamic based on temperature, (degree day) was confirmed. With aw > 0.95, a positive correlation between AFB1 production rate and aw was found, but a negative correlation resulted with aw < 0.95. Other factors than aw play a role, but aw = 0.95 should be considered as an indicator of suitable conditions for rapid aflatoxin accumulation.  相似文献   

14.
Effect of high pressure processing (HPP) on buckwheat nutritional properties is investigated in this study. The results indicated that the digestion of buckwheat starches of untreated and HPP treated at room temperature (RT) showed an “internal corrosion” pattern. However, an “exocorrosion” digestion behavior was observed for the starches of HPP treated sample at 45 °C, which might be due to the formation of amylose–lipid complexes during the process as revealed by X-ray diffraction (XRD). HPP treatment at 45 °C increased the antioxidant activity of the buckwheat as measured using 1,1′-diphenyl-2-picrylhydrazylvalue (DPPH) and iron chelating capacity (ICC) compared to untreated sample (P < 0.05), which might be associated with the release of bound phenolic compounds. More importantly, this is the first study to investigate the ability of buckwheat extract for inhibiting the formation of fat droplets using a C3H10T1/2 mesenchymal stem cell line, and found that the extract of buckwheat after HPP treatment at 45 °C demonstrated significant anti-adipogenic effects. This study suggested the HPP treatment at an increased temperature (45 °C) achieved a better nutritional value of the buckwheat than both untreated and treated at RT.  相似文献   

15.
The effect of thermal processing on the degradation of the phytochemicals in black rice flour by means of fluorescence spectroscopy and degradation kinetics was investigated. In order to investigate the influence of food matrices, a comparative analysis between integral rice flour and different fractions was performed. The preliminary compositional results suggested a higher content in phytochemicals in fraction four of the seven fractions of black rice flour, which was sifting through a sieve with a diameter of 180 μm. The compositional complexity was highlighted by fluorescence spectroscopy. The heat-treatment caused structural changes that led to red- or blue-shifts in maximum emission. The first-order kinetic model was used to describe the mechanism of degradation. The activation energies were 10.07 ± 1.04 kJ/mol for total polyphenolic, 7.26 ± 0.58 kJ/mol for total monomeric anthocyanins and 6.71 ± 1.12 kJ/mol for antioxidant activity in case of integral flour extract. For fraction four extract obtained by, the Ea values were: 3.51 ± 0.53 kJ/mol, 11.49 ± 1.47 kJ/mol, 15.80 ± 1.50 kJ/mol and 19.91 ± 3.27 kJ/mol, respectively. The calculated values of the activation energy revealed higher temperature dependence of total polyphenols in integral flour and of antioxidant activity in fraction four, respectively.  相似文献   

16.
Whole grain oat flour was extruded under different moisture contents (15%, 18%, 21%), barrel temperatures (100 °C, 130 °C), and screw speeds (160 rpm, 300 rpm, 450 rpm), and selected physicochemical properties, in vitro starch digestibility, and β-glucan extractability of the extrudates were analyzed. An increase in screw speed resulted in an increase in radial expansion index, water absorption index, and water solubility index. Screw speed significantly affected slowly and rapidly digestible starch. Moderate screw speed (300 rpm) led to higher slowly digestible starch with an accompanying decrease in rapidly digestible starch. Low moisture conditions (15%) resulted in the highest resistant starch and water-extractable β-glucan. Under the conditions used in this study, extrusion did not result in changes in water-extractable β-glucan molecular weight. Thus, extrusion might be beneficial in improving functionality and consumer acceptability by affecting physicochemical properties, in vitro starch digestibility, and β-glucan extractability of oat extrudates.  相似文献   

17.
Fusarium head blight (FHB) caused by Fusarium graminearum is one of the devastating diseases of small grain crops, including barley and wheat. Breeding for resistance is one of the best and ecofriendly strategies to manage the FHB. However, the existing methods used for screening genotypes, both under field and greenhouse conditions, often resulted in high experimental error, leading to inconsistent ranking of genotypes over years. In the postgenomic era, precise assessment of resistance is crucial to identify candidate genes. Here, we report a pathogen inoculation procedure and a real-time quantitative polymerase chain reaction (qPCR) based protocol for the quantification and discrimination of quantitative resistance among barley and wheat genotypes to FHB. Using Fusarium specific primer pair Tri6_10, for the trichothecene biosynthetic cluster (Tri6) gene, we successfully quantified the relative fungal biomass in both spikelets and rachis. A qPCR of spikelets and rachis collected on 6 dpi, from inoculated three alternate spikelet regions, discriminated resistance with less experimental error than those based on the proportion of spikelets diseased (PSD) at 9 dpi. This method can be applied for medium to high-throughput barley and wheat breeding programmes to discriminate quantitative resistance among genotypes against FHB.  相似文献   

18.
In Puerto Rico, bananas (including plantains) are important agricultural commodities; their combined production totaled over 158,000 tons in 2011. Black leaf streak (BLS) and Sigatoka leaf spot diseases, caused by Mycosphaerella fijiensis and Mycosphaerella musicola, respectively, are responsible for significant losses of this crop, due to the high susceptibility of the most important cultivars. Diploid, triploid and tetraploid hybrids were introduced from international breeding programs for evaluation in Isabela, Puerto Rico. Accessions were established in the field in a randomized complete block design and were evaluated over two cropping cycles (2007–2010) for response to BLS and agronomic traits. Significant differences (P = 0.05) in BLS severity were observed among accessions throughout both crop cycles and were most pronounced at harvest. When averaged across production cycles, severity indices at harvest ranged from very resistant (20% of the leaf surface affected) for ‘FHIA 02’ to extremely susceptible (97%) for ‘Grand Nain’. Yield attributes varied widely among the accessions, including mean bunch weights (6.9–41.0 kg), numbers of hands per bunch (6.6–13.4), and the numbers of fruit per bunch (57.0–239.2). Several accessions, mainly from the Fundación Hondureña de Investigación Agrícola (FHIA), were BLS resistant and had short pseudostems, and large bunches. They could potentially replace susceptible cultivars in commercial production or play roles in a nascent organic market.  相似文献   

19.
In order to investigate the impact of different yeast strains from the species Saccharomyces cerevisiae on the dough and bread quality parameters, wheat flour was fermented using different beer yeasts. The results show that beer yeast strains could be included in the baking process since S. cerevisiae T-58 and S. cerevisiae s-23 provided adequate gas production and dough formation with superior structural properties like extensibility and stickiness to S. cerevisiae baker's yeast. The resulting breads show the highest specific volume with the highest slice area and the highest number of cells and the lowest hardness over time. The different yeasts had also an impact on the crust colour due to their abilities to ferment different sugars and on shelf life due to the production of a range of different metabolic by-products. According to this study it was possible to produce higher quality bread by using yeast coming from the brewing industry, instead of bread containing standard baker's yeast.  相似文献   

20.
Total alkylresorcinol (AR) content and homologue composition were assessed in whole grain flours of 15 varieties each of bread wheat, durum, spelt, emmer, and einkorn grown in four different environments. Bread wheat (761 ± 92 μg/g DM) and spelt (743 ± 57 μg/g) belonging to the hexaploid species showed higher AR concentrations than the tetraploid durum (654 ± 48 μg/g, p < 0.05), while the concentrations found in the diploid einkorn (737 ± 91 μg/g) and the tetraploid emmer (697 ± 94 μg/g) did not significantly differ from the other species. The AR content showed a remarkable heritability and, thus, seemed to be mainly determined by genetic factors. If ARs were assumed to be deposited within a specific AR-rich layer of the kernel, AR levels of all varieties would easily surpass their minimal inhibitory concentrations against fungal pathogens within this barrier layer. Although the AR carrying a C21:0 side chain was the main homologue in all species, the levels of all AR homologues and their relative composition significantly differed between hexaploid (bread wheat and spelt), tetraploid (durum and emmer) and diploid (einkorn) species. Consequently, a clear-cut differentiation of Triticum species and derived whole grain flours according to their degrees of ploidy was established based on concentrations of saturated C17-, C19-, C21-, C23-, and C25-substituted ARs.  相似文献   

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