Texture measurement of cabbages using an acoustical vibration method

Textures of six cabbage cultivars were quantified using an acoustical vibration technique. A sample of four outer leaves of a cabbage was penetrated using a probe. The acoustical vibration signals were measured during penetration using a piezoelectric sensor. A new texture index (TI), the “energy density”, was introduced, which was determined by the integration of squared amplitudes of texture signals multiplied by a factor of a frequency band. This TI enabled evaluation of acoustical signals in the high-frequency region (>1000 Hz) more sensitively than the previously used index (“amplitude density”), which was determined by the integration of texture signal amplitudes. Significant differences in TI among the cultivars were obtained by using ANOVA, especially between a spring and a winter cabbage. We also examined cabbages that had been stored under 4 °C for 10 or 19 d. Most TI readings increased after the storage. These results provide useful information related to the shelf-life of cabbages.     

Non-destructive quality determination of pecans using soft X-rays

Use of soft X-ray digital imaging for non-destructive quality evaluation of pecans was explored. Unshelled pecans were imaged at various X-ray tube voltages from 15 to 50 kVp and currents from 0.1 to 1 mA. Pecan images with good contrast image were identified. The cavity inside the pecan shell and the nutmeat portion were segmented manually in the pecan radiographs. Percent nutmeat area, mean pixel intensity, and local intensity variation adequately determined nutmeat quality, non-destructively. Pecan nutmeat weight was estimated with an error of less than 10% from images taken at 35 kVp–0.75 mA, 40 kVp–0.5 mA, and 45 kVp–0.5 mA. Defects and insects were clearly differentiated in X-ray images after applying contrast stretching or high-frequency emphasis techniques.     

Genotypic difference for the susceptibility of Japanese, Chinese and European pears to Venturia nashicola, the cause of scab on Asian pears

Venturia nashicola, the cause of scab on Asian pears, is distinct from Venturia pirina, a causal fungus of European pear scab. Although scab caused by V. nashicola is one of the most serious diseases in the Japanese pear (Pyrus pyrifolia Nakai var. culta Nakai), information available regarding resistant breeding against V. nashicola is limited. In this study, 12 genotypes of Japanese pear, seven genotypes of Chinese pear (Pyrus ussuriensis Maxim.) and four genotypes of European pear (Pyrus communis L. var. sativa DC.) and/or their offspring were evaluated for susceptibility to V. nashicola with leaf and fruit inoculation tests. At 30–40 days after full bloom in their developmental stage, unfolded young leaves and fruit were inoculated with conidial suspensions of V. nashicola for each genotype, and the responses were rated at 30 days postinoculation for the inoculated leaves and at 42 days postinoculation for the inoculated fruits. No visible symptoms were found in European pear ‘Bartlett’ and ‘La France’ and their respective offspring ‘290‐36’ and ‘282‐12’, in the Japanese pear ‘Kinchaku’ and in the Chinese pears ‘Cangxili’ and ‘Hongli’; these genotypes were evaluated as highly resistant to V. nashicola. Necrotic lesions without sporulation were observed in the Chinese pears ‘Qiubaili’, ‘Manyuanxiang’, ‘Yuanbali’ and ‘Xiangyali’, which were regarded as resistant. Sporulating lesions were formed on the other genotypes, such as the major Japanese pear cultivars ‘Kosui’ and ‘Nijisseiki’, which were regarded as susceptible. The response of inoculated leaves coincided well with that of inoculated fruit for each genotype. When the severity of scab symptoms on scab‐susceptible genotypes was further rated with disease severity (DS) values, a genotypic difference was observed for overall DS values in a successive 2‐year measurement among the susceptible genotypes. Based on the DS values of leaf and fruit scabs, the Japanese pears ‘Niitaka’, ‘Shinko’, ‘Nijisseiki’, ‘Gold Nijisseiki’, ‘Osa Nijisseiki’ and ‘Shinsui’ were considered to be less susceptible to V. nashicola than the typical susceptible cultivar ‘Kosui’.     

种子无损分选新技术研究进展

综述了近年发展起来的种子无损分选新技术;阐述了各种分选方法的基本原理;分析了各种分选方法的特点和不足,以期为种子分选技术的进一步发展提供参考.     

Genetic improvement of legumes using somatic cell and molecular techniques

Summary The merits and limitations of somatic cell techniques involving Agrobacterium-mediated transformation, direct gene transfer and protoplast fusion, are discussed in relation to the genetic improvement of forage and grain legumes. Whilst progress with legumes is limited compared to that with plants of other families such as the Solanaceae, the fact that many legumes are readily amenable to tissue culture now permits somatic cell techniques to be targetted to these species. Future development of the subject will necessitate close collaboration between molecular biologists and plant breeders to enable novel plants generated by in vitro technologies to be incorporated into conventional breeding programmes.     

水稻Wxmp背景下SSIIa和SSIIIa等位变异及其互作对蒸煮食味品质的影响

In order to explain the variation of eating and cooking quality (ECQ) in different semi-waxy rice lines with Wx^mp allele, sixty-four semi-waxy lines with Wx^mp were developed by crossing from Wujing 13 and Kantou 194 (Milky Princess). The polymorphism of markers between the two parents was detected in soluble starch synthesis genes SSIIa and SSIIIa but not in other starch synthesis related genes. Genetic effects of SSIIa and SSIIIa on the amylose content (AC), gel consistency (GC), gelatinization temperature (GT) and rapid visco analyzer (RVA) profile characteristics were analyzed in Wx^mp rice lines. The results showed that SSIIa and SSIIIa had significant effects on the characteristic values of AC, GT, GC and RVA profile, and the interactive effects existed between the two genes. SSIIa² and SSIIIa² alleles (² indicated that allele was derived from Wujing 13, the same as in the below) had a tendency to increase AC by 1.87% and 1.23%, respectively. This result was consistent in two years. There was no significant effect on GT for SSIIa and SSIIIa allelic variation, whereas the GT of SSIIa¹SSIIIa¹(¹ indicated that the genes were derived from Kantou 194, the same as in the below) was significantly higher than that of SSIIa²SSIIIa² by 1.34 °C. This indicated that GT was not significantly affected by single gene of SSIIa and SSIIIa but was remarkably influenced by the interaction of the two genes. The GC was significant varied among rice lines with different genotypes. The SSIIa² and SSIIIa¹ alleles could increase GC of 8.74 mm and 9.62 mm respectively. From the interaction of the two genes, the GC of SSIIa²SSIIIa¹ genotype was 10.64 mm higher than the SSIIa¹SSIIIa² genotype, and was 16.95 mm higher than the SSIIa²SSIIIa² genotype. The allele SSIIa² increased the peak viscosity (PKV), hot paste viscosity (HPV), cool paste viscosity (CPV) and breakdown viscosity (BDV), but decreased the consistency viscosity (CSV) and setback viscosity (SBV). However, the effect of allele SSIIIa² was just the opposite, which decreased the PKV, HPV, CPV, BDV and increased CSV and SBV. For the combination of SSIIa and SSIIIa, SSIIa²SSIIIa¹ genotype showed the largest values in PKV, HPV and CPV, SSIIa²SSIIIa²genotype showed the largest values in BDV and CSV, and SSIIa²SSIIIa¹ genotype showed the least value in SBV. These results provide a theoretical basis for improving eating and cooking quality of semi-waxy japonica rice.     

Evaluation of screening techniques and determination of criteria for assessing resistance to Corynebacterium michiganense in tomato

Summary When screening populations segregating for resistance to Corynebacterium michiganense a rapid and reliable inoculation technique is needed. From the several techniques tested, inoculation of the petiole was found to give better differentiation of resistant and susceptible plants than did inoculation of the root or leaf. When petiole-inoculation was compared with stem-inoculation the latter showed the lowest environmental variation and is suggested for use in genetic studies. Stem-inoculation involved clipping the stems of 4 week old seedlings 1 cm above the cotyledonary leaves with scissors which had been dipped in inoculum.Petiole inoculation and, to a lesser degree, stem inoculation failed to produce uniform infection, resulting in variation in the expression of the disease. The scoring was therefore based on the presence, and not the degree, of wilting and stunting, or the size of the cankers. Plants free of all these symptoms were rated resistant. The coefficient of variation for vascular discoloration on individual plants was calculated to be 50%, which in part may be explained by the histopathology of the host.The virulent isolates cm 21 caused death of seedlings resistant to isolate H. However, cultivars resistant to isolate H in the seedling stage did not decrease in fruit weight as compared to susceptible cultivars when inoculated with isolate cm 21 at anthesis.Michigan Agricultural Experiment Station Journal No. 7424.     

Identifying the alien chromosomes in wheat – Leymus multicaulis derivatives using GISH and RFLP techniques

Genomic in situ hybridization (GISH) and restriction fragment length polymorphism (RFLP) were used to identify the Leymus multicaulis (XXNN, 2n = 28) chromosomes in wheat-L. muliticaulis derivatives. Fifteen lines containing L. multicaulis alien chromosomes or chromosomal fragments were identified. All alien chromosomes or fragments in these 15 lines were from the X genome and none were from the N genome. Eleven L. multicaulis disomic addition lines and four translocation-addition lines were identified with chromosome rearrangements among homoeologous groups 2, 3, 6 and 7. Only homoeologous group 1 lacked rearrangements in addition or translocation chromosomes. The results revealed that translocation in non-homoeologous chromosomes widely exists in the Triticeae and therefore it is necessary to identify the alien chromosomes (segments) in a wheat background using these combined techniques. During the course of the work, probe PSR112, was found to detect X genome addition lines involving L. multicaulischromosomes. This may prove to be a valuable probe for the identification of alien chromosomes in a wheat background. This revised version was published online in August 2006 with corrections to the Cover Date.     

Effectiveness of 1-MCP treatments on ‘Bartlett’ pears as influenced by the cooling method and the bin material

Wooden bin-stored ‘Bartlett’ pears (Pyrus communis L.) were hydrocooled (HC) or forced-air cooled (FAC) and immediately treated or not with 1-methylcyclopropene (1-MCP) for 24 h. 1-MCP gas concentrations used were 0, 0.3 or 0.6 μL L^?1 (called 0, 0.3 and 0.6, respectively). Fruit were subsequently kept at 20 °C for 20 d or stored at ?0.5 °C and 95% RH for 60, 90, 120 or 150 d. After cold storage, fruit were kept at 20 °C for up to 16 d for further ripening. In another experiment, pears stored in wooden bins (W) or plastic bins (P) were all hydrocooled, treated or not with 0.5 μL L^?1 1-MCP (called 0.5 and 0, respectively), stored at ?0.5 °C and 95% RH for 0, 30, 60, 90 or 120 d, and transferred to 20 °C for further ripening. In FAC pears, increasing 1-MCP concentrations usually resulted in delayed increases in ethylene production and lower ethylene production rates, as well as delayed softening. In contrast, HC-0.3 pear firmness did not differ from that of HC-0 fruit after cold storage. Generally, HC-0.3 pears displayed higher ethylene production and lower firmness values than FAC-0.3 pears after a 7-d exposure to 20 °C, regardless the length of cold storage. FAC-0.6 pears always showed lower ethylene production rates and higher flesh firmness values than HC-0.6 fruit. Soluble solids concentration was not consistently affected by 1-MCP. FAC-0.3 and HC-0.6 fruit showed higher titratable acidity values than HC-0 fruit after 0, 60, 120 and 150 d of cold storage plus 7 d at 20 °C. Effectiveness of 1-MCP treatments on HC pears was influenced by the bin material; P-0.5 pears were firmer than W-0.5 pears after 7 d at 20 °C, regardless the length of the cold storage. HC-0.5 fruit exposed to ?0.5 °C for 90 d reached eating quality (firmness ≤23 N) by day 7 if placed in W, and by day 21 when stored in P. Results and previous evidence suggest that wet wooden bin material may represent a major though unpredictable source of 1-MCP sorption that could bind a significant percentage of the 1-MCP applied. When used at relatively low doses 1-MCP partial removal by wet wooden bins can compromise the application effectiveness for controlling ethylene action.     

Combined effects of sodium chlorite dip treatment and chitosan coatings on the quality of fresh-cut d’Anjou pears

This study evaluated the effects of sodium chlorite (SC) alone and its sequential treatment with edible coatings on browning inhibition and quality maintenance of fresh-cut d’Anjou pears. Edible coatings were prepared from chitosan (CH) and its water-soluble derivative carboxymethyl chitosan (CMCH), separately. Pear wedges were immersed in SC solution, followed by coating with CH or CMCH solutions. The samples were packed in unsealed bags and stored at 4 °C for subsequent color, firmness, and weight loss measurement. The effects of the SC and coating treatments on polyphenol oxidase (PPO) inhibition and microbial inactivation were also evaluated. Results indicated that SC exhibited significant (P < 0.05) inhibition of browning and PPO activity. The SC treatment was also strongly effective in inactivating Escherichia coli O157:H7 on pear slices. Coating SC-treated pear slices with CH adversely affected the quality of pear slices by accelerating the discoloration of cut surfaces and increasing the PPO activity. On the contrary, coating SC-treated samples with CMCH significantly prevented the browning reaction and inhibited PPO activity. In addition, SC and CH/CMCH coatings maintained tissue firmness and did not affect weight loss. Our study may provide a scientific basis for the use of SC + CMCH treatment as an alternative preservation treatment for fresh-cut fruits and vegetables.     

Effect of high-pressure hot-water washing treatment on fruit quality, insects, and disease in apples and pears: Part I. System description and the effect on fruit quality of ‘d’Anjou’ pears

A manually operated high-pressure hot-water washing system consisting of a boiler, hot-water mixing tank, contact loop, heat exchanger, spray mixing tank, high-pressure hot-water washing manifold, low-pressure fresh water rinse manifold, and pressure pump was constructed and installed in a packingline. The system developed 20–50 °C washing water at pressures up to 980 kPa. ‘d’Anjou’ pears (Pyrus communis L.), shortly after harvest, and after storage for 3 and 4 months in regular air (RA) or for 4, 7 and 8 months in controlled atmosphere (CA) at −1 °C were washed through the packingline with different wetting agents (0.1% Silwet, 0.01 and 0.1% Defoamer, and water), water pressures (regular and high-pressure (210–980 kPa)), water temperatures (control (tap water, 4–22 °C), 40 °C, and 50 °C), and brushes (soft and firm), respectively. The effect of the washing conditions on fruit quality was investigated after 1 month of storage at −1 °C to simulate shipping condition, and then again after 1 week at 20 °C to simulate marketing condition. Hot-water caused severe heat scald. When nozzle temperature was 50 °C, the incidence of heat scald increased to over 50% for the fruit stored in RA for 3 months. Combined with hot-water, 540 kPa high-pressure washing increased the incidence of friction discoloration. There were lower incidences of friction discoloration and heat scald for fruit stored in CA for 7 months, in comparison to that in RA for 3 months. However, those fruit did not ripen properly as indicated by a high extractable juice content. Fruit washed at harvest had minor incidences of friction discoloration regardless of different brushes, water pressures, and wetting agents. Fruit washed after storages in either 4 months RA or 4 or 8 months CA suffered a high incidence of friction discoloration including scuffing symptoms and pressure marking. The firm brushes caused a higher incidence of friction discoloration mainly because of scuffing symptoms. However, no differences were found between different water pressures and wetting agents with respect to friction discoloration. Fruit stored for 4 months RA suffered 26–28% friction discoloration in comparison to 16–18% in CA stored fruit with firm brush washing. Extended CA storage increased friction discoloration even with soft brush washing. The results suggest that a washing system with high-pressure spray, <30 °C warm water, wetting agent Defoamer and rotating soft brushes were significantly effective in removing surface pests and decay control without causing internal or external damage of fruit.     

Effect of fruit moving speed on predicting soluble solids content of ‘Cuiguan’ pears (Pomaceae pyrifolia Nakai cv. Cuiguan) using PLS and LS-SVM regression

Visible (Vis)/near infrared (NIR) spectroscopy is an excellent technique for non-destructive fruit quality assessment. This research was focused on evaluating the use of Vis/NIR spectroscopy for measuring soluble solids content (SSC) of intact ‘Cuiguan’ pears (Pomaceae pyrifolia Nakai cv. Cuiguan) on-line. Also, the effect of fruit moving speed on SSC measurements was investigated. Diffuse transmission spectra were collected using a fiber spectrometer equipped with a 3648-element linear silicon CCD array detector in the wavelength range of 345–1040 nm, and all sample spectra were collected three times at different fruit moving speeds of 0.3 m s^?1, 0.5 m s^?1 and 0.7 m s^?1. Spectral pre-processing such as derivative, standard normal variate transformation (SNV) and multiplicative scatter correction (MSC) was used before calibration. Partial least squares (PLS) and least squares support vector machines (LS-SVM) were used to develop calibration models for SSC. The results show that fruit moving speed has few effects on spectra and model performance at a fruit moving speed of 0.3–0.7 m s^?1. At 0.5 m s^?1, the best model for SSC was PLS regression coupled with original spectra, its coefficient of determination (R²) and root mean square error of prediction (RMSEP) being 0.916% and 0.530%, respectively.     

Influence of the stage of ripeness on phenolic metabolism and antioxidant activity in table grapes exposed to different CO2 treatments

We have analyzed the influence of the stage of ripeness on L-phenylalanine ammonia-lyase (PAL) gene expression, accumulation of anthocyanins and total phenolics, and on antioxidant activity in the skin of table grapes treated with 20% CO₂ + 20% O₂ + 60 % N₂ for 3 or 6 d at low temperature (0 °C). The residual effect of high CO₂ treatment after transfer to air was also studied. In early harvested grapes, neither the anthocyanin content nor the accumulation of VcPAL mRNA was affected by any of the CO₂ treatments applied. However, in late harvested grapes, the duration of high CO₂ treatment determined its effect and a 6 d treatment with CO₂ sustained higher levels of total phenolics and anthocyanin accumulation, and VcPAL expression than observed in untreated late harvested grapes. The increased antioxidant capacity was correlated with the total amount of phenolics and anthocyanins. Conversely, in grapes treated for 3 d with CO₂ the phenylpropanoid pathway did not appear to be induced and a relationship between antioxidant activity and anthocyanins was not observed. Thus, further studies are needed to identify the most important antioxidants in these treated fruit.     

The determination of suspended metals in coastal waters by different sampling and processing techniques (filtration,centrifugation)

The concentrations, on a sediment weight basis, of several metals in coastal suspended matter show a marked dependence on the amount of particulate matter per litre. The effects of filtration and centrifugation are compared. The resulting data are interpreted in terms of varying contributions of larger and denser bottom derived particles with higher concentrations of K, Fe, Mn, and Al and of smaller and less dense, continuously suspended particles with higher concentrations of Cu, Cd, Pb and Zn. No dependence on size or density was found for Cr, Si, Mg and Ca.Filtration results in higher concentrations of Cu, Cd, Pb, and Zn. For the other elements, centrifugation results in concentrations that are at least similar to those in particulates obtained by filtration, or even larger for elements with relatively large difference between the concentrations in the different fractions, such as K. Leaching particulates, obtained by filtration and centrifugation, with 0.1 N HCl leads to differences in the leached fractions for Cd, Cr, K and Mg at lower suspended loads, and for Fe at higher loads, while no differences are observed for Cu, Pb, Zn, Si, Mn, Al and Ca.Accurate particulate metal concentration data were obtained by measuring in each individual sample, the amount of both metal and particulate matter. This results in more accurate data than can be obtained by measuring each of the properties in separate samples. Another source of errors is eliminated by analyzing the entire content of a sampler in stead of part of it, because of sample inhomogeneity introduced by settling of particles in the sampler.In order to get accurate sediment weight data at low suspended matter concentrations, sea salt was removed from the particulate matter by a rinsing procedure with distilled water. No loss of the metals investigated (Cu, Cd, Zn, Cr, Si, Fe, Mn, and Al) was evident with a possible exception for Cd.     

Predicting sensory attributes of different chicory hybrids using physico-chemical measurements and visible/near infrared spectroscopy

Chicory (witloof) is a typically Belgian vegetable appreciated for its slightly bitter taste. Up until now no measurements exist to objectively quantify the sensory characteristics of chicory. Taste and texture of nine different chicory hybrids were analyzed by sensory and instrumental analysis (three-point bending test, high performance anion exchange with pulsed amperometric detection, high performance liquid chromatography and visible/near infrared spectroscopy). The main objective of the study was to correlate and predict the sensory attributes and consumer acceptance of chicory with destructive physico-chemical measurements and non-destructive Vis/NIR data, to avoid time- and money-consuming sensory profiling in the future. A univariate analysis showed that glucose and sucrose concentrations in chicory leaves were highly correlated with the attributes crunchiness and bitterness. The fructose concentrations however were correlated with the sweetness score of the panel. When performing partial least squares on all destructive instrumental parameters and Vis/NIR data for the major sensory attributes of chicory, satisfactory prediction models (ratio of standard deviation to root mean square error of cross-validation (RPD) > 2) could be established for all attributes but sweetness using all physico-chemical parameters. Using Vis/NIR data improved the prediction capacity of the sweetness model, and this technique proved to be useful in predicting the sensory quality of chicory.     

DNA fingerprinting of Indian cashew (Anacardium occidentale L.) varieties using RAPD and ISSR techniques

Indian cashew breeding programme has produced 24 selections and 11 hybrids with increased yield and excellent nut characters. Molecular profiles of these varieties were developed using a combination of five RAPD and four ISSR primers pre-selected for maximum discrimination and repeatability. A total of 94 markers were generated which discriminated all the varieties with a probability of identical match by chance of2.8 × 10^-11. There was no correlation between the relationships based on molecular data and the pedigree of the varieties. Narrow range of average similarity values among major cashew breeding centres with only 3.6% of molecular variance partitioned between them was attributed to the exchange of genetic material in developing varieties. Difference in the average similarity coefficients between selections and hybrids was low indicating the need and scope for identification of more parental lines in enhancing the effectiveness of hybridisation programme. This revised version was published online in August 2006 with corrections to the Cover Date.     

Mutation breeding of Chrysanthemum morifolium Ram. using in vivo and in vitro adventitious bud techniques

Summary During experiments, which are being carried out to study the factors which control the process of adventitious bud formation in vivo on detached leaves of Chrysanthemum morifolium Ram, adventitious shoots were produced from leaves, irradiated with 500 rad of X-rays. The most important but disadvantageous result was that the majority of the adventitious shoots proved to be of a chimeral nature and obviously developed from more than one cell.An in vitro adventitious bud technique was developed using different types of explants. Pedicel segments regenerated the highest number of adventitious shoots and, moreover, they developed faster as compared to explants of young flower heads or leaves. The mutants produced by irradiating the various explants were almost exclusively of a solid (non-chimeral) nature. In addition, histological observations suggest that single epidermal cells are involved in the initiation of the adventitious shoot apices.The optimum dose for mutant production is approximately 800 rad X-rays. Rather often, more than one phenotypically identical mutant was found, which was always derived from the same explant. They could for instance originate from a multi-apical meristem formed by a single mutated cell.     

Effects of harvest time and low temperature storage on the texture of cabbage leaves

Leaf textures of four cabbage cultivars (T-520, Fuyu-nobori, Satsuki-ou, and Kinkei-201) harvested in winter and spring were evaluated. Acoustic vibration signals generated during penetration of four stacked cabbage leaves were measured using a novel texture measurement system. Texture was quantified using a texture index (TI). The TI of T-520 was higher than that of Fuyu-nobori and continually declined during the entire investigation period (between February and May). However, Fuyu-nobori's TI persisted after early April. This implied that Fuyu-nobori was superior to T-520 in terms of preservation of quality. Satsuki-ou showed either an equivalent or higher TI than T-520 in May. Kinkei-201 had a much lower TI than the other cultivars. TIs of T-520 and Fuyu-nobori stored at a 5 °C for 4 weeks were lower than those of samples without storage. This implied that low temperature storage did not effectively retain the texture quality of the cabbages.     

切割片减振降噪的优化设计

为了研究切割片在工作过程中的振动及噪声问题,基于有限元方法,借助于ANSYS APDL有限元软件建立了切割片有限元模型;采用反转法施加载荷,简化模型及分析过程,在振动特性分析中,得出调整切割片结构参数可以降低切割片振动幅度的结论;基于振动能量与速度的平方关系,以测试点的速度平方和为目标函数,设计了优化程序对切割片模型进行调整优化,获得了一组最优调整数据,为实际生产提供了参考依据。