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When apples which develop low temperature breakdown (LTB) at 32° F. are moved from 32° F. to 65° F. for 3 to 5 days at about the 7th to 8th week of storage, they subsequently develop within a given period of storage less LTB than apples kept at 32° F. continuously.

The respiration of apples susceptible to LTB increases steadily during storage at 32° F. If these apples are warmed to 65° F. during the period of exposure to 32° F., the subsequent rate of respiration at 32° F. is lower than before warming, and continues at a lower rate than for apples kept at 32° F. continuously.

If the apples are moved to 38° F., without an intermediate treatment at 65° F., the rate of respiration is higher than for apples at 38° F. continuously, and this higher rate persists.

If there is an intermediate wanning period at 65° F., the respiration of apples moved from 32° to 38° F. is of the same order as that for apples kept at 38° F. continuously.

The respiratory quotient of apples at 32° F. or at 38° F., which is indicative of the type of respiratory activity, is typical for the temperature at which it is measured, and is not affected by the warming treatment. The effects of wanning on both the incidence of LTB and respiration are similar for apples stored in air and in 2% oxygen: 98% nitrogen.  相似文献   

3.
A trial on ‘Fuji’ apples at the Grove Research Station in southern Tasmania during the 1991/92 season studied the thinning effect and interactions between ethephon and benzyladenine (BA) when BA was applied as a secondary thinner after a full bloom (FB) application of ethephon. The spray treatments were a factorial combination of eight application times of BA (11,13,15,17,19, 21, 23 or 25 days after full bloom (AFB)) with ten concentrations (20,40,60,80,100,120,140,160,180 or 200 mg I“1). An unsprayed control and an ethephon control were included. Target thinning results were achieved 19- 23 d AFB with concentrations of 140-160 mg I“1. A corollary of this successful thinning was an increase in fruit weight and size. Return bloom was improved significantly where thinning was successful. There was no effect on fruit firmness, soluble solids or lateral branching. Drawbacks were an increase in the incidence of russet and a reduction in pip number at the optimum thinning times and concentrations.  相似文献   

4.
Summary

The present work investigated the effects of different aqueous extracts of organic waste compounds on growth, proliferation and photosynthetic activity in ‘M9’ (Malus domestica Borkh.) shoot cultures, with the aim of determining the feasibility of using in vitro cultures as a tool for the rapid evaluation of organic amendments in agriculture. Aqueous extracts of the following organic waste compounds: cow manure (CM), sugarbeet industrial waste (SB), mixed grape, poultry and municipal solid waste (GPM), and citrus pruning and industrial waste (CPI) were prepared at a rate of 1:10 (w/v) compound:distilled water. The basal media used in the proliferation phase were: (i) PM1, modified Murashige and Skoog (MS) enriched with 4.4 µM 6-benzyladenine (BA); (ii) PM2, as PM1 but with a reduced cytokinin concentration (1 µM BA) to evaluate possible hormone effects; and (iii) PM3, 4.4 µM BA with reduced salt strength (0.33 MS) to induce nutrient deficiency. Hormone-free medium with half-strength MS salts was used for rooting. All media were enriched with each extract at 0, 0.2, 2, 20 or 200 ml l–1. Photosynthetic activity was measured on PM3 medium enriched with SB or CM. Standard culture conditions were 22° ± 2°C, with a 16 h photoperiod at 30 µmoles photosynthetically active radiation (PAR) m–2 s–1, but at 80 µmoles PAR m–2 s–1 to determine photosynthetic activity. Shoot weight increase in PM1 was not affected by the GPM and CPI extracts, while the growth trends of CM- and SB-treated shoots were described by a second-degree function with maxima at 2 ml l–1 and 0.2 ml l–1, respectively. Shoot proliferation for SB was represented by a quadratic curve (maximum at 2 ml l–1), was linearly reduced as GPM increased, but was not affected by CM or CPI. Treatments did not significantly affect rooting percentage and root length; however root number was increased by SB at 2 ml l–1.CO2 fixation increased linearly with both SB and CM, despite reduced growth at the highest levels of extract.  相似文献   

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This study was carried out in Arsin (Trabzon/Turkey) in 2011. The effects of different harvest time and altitudes on the quality of the nuts have been investigated. The study was performed on Fo?a hazelnut and the harvest process has been conducted at three terms, which are on normal harvest time and ten days before and after harvest time. The harvested nuts were dried in the shade on the concrete floor until their moisture content decreased to 5?%. Some properties of nuts including yield, fruit weight, internal weight, shell thickness, and protein, oleic, and linoleic acid amounts have been investigated. As evaluated all of the fruit properties it can be concluded that 11 August is the most suitable harvest date for coast zone. On the other hand, no significant differences were obtained in the point of protein, oleic, and linoleic acid amounts for different harvest time and altitudes.  相似文献   

7.
Summary

Spurs of ‘Nijisseiki’ pear (Pyrus pyriflora Nakai) were allowed to assimilate 10033;CO2 at 87.d after anthesis (DAA) and at 108 DAA during the period of rapid fruit growth. Then the spurs were sampled periodically until fruit harvest time to trace the time course and amount of movement of assimilates from spur leaves to individual organs in the spur. The amount of 10033;C absorbed by fruit within 3.d after labelling was constant until harvest, regardless of the labelling date. However, the total amount of 10033;C in the spur decreased continually until harvest.Of the total amount of 10033;C recovered in the spur labelled at 87 DAA, by harvest, 43.2% of 13C was found in the fruit flesh (cortex of receptacle), 5% in the core (pith of receptacle 1 pericarp 1 seeds), 5.6% in spur stem, 5.4% in the source leaves, and 40.8% was respired and exported from the spur. Of total amount of initial 10033;C labelled at 108 DAA, at harvest, the proportion of 10033;C translocated to flesh, core, stem, respired, and remaining in leaves was 61%, 6.1%, 3.0%, 24% and 5.4%, respectively. Photosynthates fixed by the spur early in the rapid growth stage of the fruit contribute more to the formation of starch and structural materials and less to solublecarbohydrates in fruit than do those fixed later.  相似文献   

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The effect of carbon and nitrogen sources, pH, temperature and substrate water content on the growth and vigor of Sparassis crispa mycelium was evaluated. Mycelial growth rates were highest when rice starch served as the carbon source and when peptone, yeast extract or soybean meal were adopted as the nitrogen source. The optimum pH and substrate water content values were 5.25 and 62.5% respectively. Mycelial growth was optimal at 20.2 ℃ and inhibited at 35 ℃, and temperatures of 40 ℃ and above killed the fungus.  相似文献   

10.
There is an ongoing debate as to whether nutrient contamination of groundwater under agricultural fields may cause nutrient-enrichment and subsequent eutrophication in discharge areas. Often, there is only circumstantial evidence to support this supposition (proximity of agricultural fields, direction of water flow, highly productive vegetation). Research on solute transport along a flow path is necessary to evaluate the risk for eutrophication. In this paper we present results of such a study. Two transects were established in a discharge meadow, a few meters downstream from fertilized cornfields. Highly productive vegetation in parts of the meadow suggested nutrient-enrichment caused by inflow of contaminated groundwater. This supposition was supported by an analysis of groundwater flow paths, residence times and chloride as tracer for pollution. However, the fate of nutrients along the flow path indicated otherwise. While we found high concentrations of DIN (dissolved inorganic nitrogen), P and K under the cornfields, DIN and P concentrations drop below detection limit when groundwater enters the meadow. Only K progressed into the meadow but did not enter the root zone. We conclude that (1) polluted groundwater from the cornfields did not cause the nutrient-enrichment, as indicated by the highly productive vegetation. Restoration projects in discharge areas should not focus upon measures in upstream areas if only circumstantial evidence is available. Solute transport should be considered as well. (2) Because K clearly showed to be the most mobile nutrient, its importance for nutrient-enrichment in discharge wetlands merits more attention in future research.  相似文献   

11.
AIM: To explore the effect of 4-hydroxytomacifen (4-OHT) on MER-Syk(L) cellular localization and the function of Syk(L) on cell proliferation in breast cancer cells.METHODS: pcDNA3.1(+)-MER-Syk(L) vector was constructed and the cell line MDA-MB-231, which expressed MER-Syk(L) stably, was established. Western blotting and immunofluorescence techniques were used to detect localization of MER-Syk(L) fusion protein in MDA-MB-231 cells cultured with or without 4-OHT. MTT assay was used to explore the proliferation ability of MDA-MB-231 stable cells.RESULTS: (1) MER-Syk(L) fusion protein, not MER-Syk(S) and MER protein, translocated from cytoplasm to nucleus in the presence of 4-OHT. (2) Nuclear not cytoplasmic MER-Syk(L) fusion protein inhibited MDA-MB-231 stable cell growth. (3) With or without the treatment of 4-OHT, MER-Syk(S)and MER protein always located in cytoplasm and did not suppress cell growth.CONCLUSION: With 4-OHT, MER-Syk(L) fusion protein translocates to nucleus and inhibits cell growth.  相似文献   

12.
AIM: α-MSH is elevated in patients with inflammatory bowel disease and has been implicated as an inflammatory mediator. The purpose of this study was to investigate effects of α-MSH on the Ca2+ channels of primary DMNV cells, the effects of gastrointestinal inflammation on the dorsal motor nucleus of the vagus in rats, as well as the effects of proinflammatory cytokines and α-MSH on neurons from the dorsal motor nucleus of the vagus in vitro. METHODS: In vitro studies the primary culture of neurons from the dorsal motor nucleus of the vagus was performed. Single-cell cytoplasmic calcium transients were determined using the fluorescence dye fura-2-AM. Cell proliferation and apoptosis were measured by enzyme-linked immunosorbent assay. RESULTS: MC4R mRNA was expressed in the DMNV cells of normal rats. Activation of MC4R promoted the calcium influx of primary DMNV cells. The addition of α-MSH to thrombin or trypsin resulted in significant decreases in apoptosis compared to thrombin or trypsin alone. CONCLUSION: Functionally active α-MSH receptors are linked to Ca2+ channels in DMNV neurons. In cultured DMNV cells, α-MSH attenuates neuronal apoptosis and reverses inhibition of cellular proliferation.  相似文献   

13.
Gamma-rays are an important mutagenic agent that can induce new, useful genetic variations in plants. However, γ-irradiation can also cause damage that negatively affects the use of such mutagens in plant breeding. The aim of the present study was to investigate the effects and damage caused by γ-radiation in a Cymbidium hybrid, RB001. The relative growth rate of protocorm-like bodies (PLBs) was reduced by 50% at a γ-ray dose of approximately 40 Gy. Malondialdehyde concentrations increased significantly with increasing radiation dose. However, almost no difference was observed between untreated control PLBs and PLBs treated with 200 Gy 8 weeks after γ-irradiation. The activities of several antioxidant defence enzymes increased gradually with increasing γ-ray dose, 24 h after irradiation. These enzymes showed different responses between 1 and 4 weeks, but no difference 8 weeks after irradiation. The ‘comet assay’ and flow cytometry were performed. Clear differences in radiation-induced damage were observed between control and 200 Gy-treated PLBs at 24 h. However, PLBs had a tendency to recover from 4 weeks after irradiation, and the integrity of their DNA was similar in samples treated with 10–200 Gy. These results indicated that γ-rays caused little DNA damage and the plants could recover. This demonstrated the feasibility of using physiological responses, the ‘comet assay’, and flow cytometry to detect DNA damage after γ-irradiation.  相似文献   

14.
【Objective】To explore the rules of intra-specional and inters-pecific cross breeding of some new sweet cherry cultivars and improve the efficiency of cross breeding of sweet cherry in the area where winter is warm and summer is hot and moist.【Methods】The intraspecial and interspecifichybridization test of sweet cherry was carried out by using sweet cherry as the mother,using sweet cherry and chinese cherry as the father. The rate of fruit set,embryo,embryo abort of the cross and quality of the F0 fruit were investigated in order to analysis the efficiency of the cross.【Results】The four cultivars of sweet cherry‘Jiangnanhong’‘Chaoyang-1’‘Changfeng-1’and‘Van’were taken as the mother. Five sweet cherry cultivars or selections‘04-8’‘04-11’‘Chaoyang-1’‘Van’‘Lapins’and five cultivars of chinese cherry‘Chaozaohong’‘Duanbing’‘Gejiawu’‘Heizhenzhu’‘Zijing’were taken as the male parent. Among them‘Jiangnanhong’and‘Zijing’are newly identified cultivars in Zhejiang province,and‘Chaoyang-1’and‘Changfeng-1’are new selections. After pollination for 1 week,the fruit setting rate was relatively high and significant decrease in the 4 weeks and mature stages in intra and inter- species with the development of fruits. In the mature stage,all the fruit setting of the other cross of intra-species were higher than 5%,except that of‘Jiangnanhong’ב04-11’was 1.85% lower than 3%,and that of‘Changfeng-1’בLapins’was 4.35% lower than 5%,which indicates the basic affinity between the cross of intra-specific sweet cherry. The fruit setting rate of intraspecific cross was higher than that of interspecific cross. The fruit setting rate of‘Chaoyang-1’was the highest in both intraspecific and interspecific hybridization. The interspecific hybrid combination of‘Changfeng-1’had the lowest fruiting rate. The embryo rate and abortion rate of the intraspecific cross were higher than those of interspecific cross when the female parent is same. The abortion rate is high when hybrid embryos mature,and only 4 crosses group can obtain non-abortion embryos,which are the hybrid cross of‘Jiangnanhong’with‘04-8’‘Lapins’‘Chaozaohong’,and the cross of‘Changfeng-1’with‘Van’. The abortion is lower when the hybrid embryos immature. The embryo rate was lowest and the abortion degree was the highest of the cross of‘Jiangnanghong’in immature embryo stage. The cross with the mother of‘Chaoyang-1’was the best with high setting rate,high embryo rate and low abortion rate in immature embryo stage,so‘Chaoyang-1’is the best female parent in this test.‘Chaoyang-1’and‘Zijing’were the better fathers in the ten test male parents for the cross with them had a high embryo rate (65.84% and 75.21%,respectively),and most of the embryos were bright white and full with good development in the immature embryos stage. ‘Chaoyang-1’is the best female and male parent in this test. The cross between‘Chaoyang-1’and‘Van’shows‘Chaoyang-1’is the better female than male parent. The ripening stage of F0 fruit was delayed,and the color and shape of F0 fruit showed the same col- or and shape of open pollination of parent fruit. The soluble solid of interspecific hybrid fruit was lower than that the intra-specific hybrid,and they all lower than that of the open pollinated female fruit. In order to obtain hybrid offspring,the author suggests three methods could be used in the area where is warm in winter,hot and moist in summer: one is selecting hybrid offspring which comes from the main producing areas,which means making cross and getting hybrid offspring in the main producing areas but select it in future planting area. The other is using embryos rescue technology after getting immature fruit; the third one is using mixed pollen for open pollination.【Conclusion】The fruit set and embryo development have significant differences among the different cross group in the area where winter is warm and summer is hot and moist. The fruit set is higher and the embryo abort is lower of intraspecific cross than that of interspecific cross when the mother is the same sweet cherry.‘Chaoyang-1’is the best female and male parent in this test when making cross. © 2019 Journal of Fruit Science  相似文献   

15.
AIM:To study the protective effect of hyperpolarized cardioplegic arrest on reperfused rat heart performance and to investigate the role of mitochondrial ATP-sensitive K+ channels (mitoKATP) opening in the protection of hyperpolarized cardioplegia against ischemia/reperfusion damage. METHODS:Forty Sprague-Dawley rats were randomized into five groups (n=8 in each group): control group (Con); depolarized arrest group (D); hyperpolarized arrest group (H); depolarized cardioplegia with 5-hydroxydecanoate (5-HD) group (5HD+D); hyperpolarized cardioplegia with 5-HD group (5HD+H). The rat hearts were quickly removed to Langendorff apparatus. The heart perfusion was performed for 20 min with 37 ℃ Krebs-Henseleit buffer balanced with gas mixture (O2∶〖KG-*2〗CO2=95%∶〖KG-*2〗5%) at 5.8 kPa perfusion pressure, then cardial arrest was induced by different cardioplegic solution. Hearts were subjected to ischemia at 37 ℃ for 40 min followed by 30 min reperfusion. (1) The hemodynamics was detected at recovery after 30 min reperfusion. (2) Before ischemia and at the end-reperfusion, tissue was harvested for mitochondrial isolation and ultrastructure was observed by transmission electron microscopy (TEM). (3) Production of reactive oxygen species (ROS) was also determined at different time points. RESULTS:(1) Compared with end-equilibration, 30 min reperfusion caused significant differences in left ventricular developed pressure (LADP), left ventricular end-diastolic pressure (LVEDP), double product (DP), heart rate (HR), coronary flow (CF) (P<0.01). TEM showed that the ultrastructures of myocardial and mitochondrial were damaged remarkably. (2) When H group was compared with D, 5HD+H and Con group, significant differences were found in LVDP, LVEDP, DP, HR and CF (P<0.01). TEM showed that the myocardial and mitochondrial ultrastructures were improved remarkably. (3) The rate of ROS generating was lower in group H than that in other four groups at end-reperfusion (P<0.01). CONCLUSION:(1) Of the four cardioplegias, hyperpolarized cardioplegia is superior to improve myocardial performance, attenuates myocardial and mitochondrial injury, and reduces rate of ROS generating. (2) Mitochondrial preservation is one of mechanisms of myocardial protection in hyperpolarized cardioplegia, opening of mitoKATP enhances cardioprotection through decreasing ROS generating, providing better energe supply for reperfused myocardium.  相似文献   

16.
【Objective】 Grape anthracnose is one of the main diseases of grape, which mainly infects the fruits, young leaves and new branches of grape, causing fruit rot, shedding, or water loss and shrinkage into stiff fruits. Breeding disease-resistant grape varieties is the most economical, effective, and environmentally friendly long-term control strategy for the prevention of the anthracnose disease. There have been a few studies on the identification of the resistance to anthracnose and the QTL localization of relative disease resistant genes so far. The study aimed to identify the resistance to the anthracnose disease of different grape germplasms and seek for new QTL locus for the resistance and provide germplasm materials and basis for the breeding and research on the disease resistance mechanism. 【Methods】 The indoor ex vivo leaf inoculation method was used to identify and evaluate the resistance to anthracnose in 60 strains of Chinese wild grapes, 122 accessions of V. vinifera and 76 accessions of V. vinifera-V. labrusca, and the hybrid offsprings of Manicure Finger (susceptible)×Ciputao0940 (resistant), and the QTL localization of grape anthracnose resistance was carried out using the genetic map constructed by SNP markers.【Results】 A total of 1 germplasm with high resistance, 43 germplasms with resistance and 75 germplasms with medium resistance were screened out, accounting for 0.39%, 16.67% and 29.07% of the total identified accessions, respectively. There were great differences in the resistance to anthracnose in different germplasm populations. 63.34% of the East Asian population 56.57% of the V. vinifera-V. labrusca population, and 31.15% of the Eurasian population had the resistance to anthracnose. In the identification of anthracnose resistance in Chinese wild grape germplasms, it was found that the resistance of different strains in the same population varied greatly, and the species with strong resistance on the whole included V. davidii, V. pseudoreticulata, V. amurensis, and V. piasezkii. The strong resistance of the strains include Shanputao &, Longyuwanfuye1 &, Duolieye-yingyu, Shanputao- shanyang1807, Mianmaoputao-chayu1955, and Ciputao0940. The resistance of the hybrid offsprings of Manicure Finger (susceptible)×Ciputao0940 (resistant) were distributed in five grades. According to the normality test and single-sample Kolmogorov-Smirnov test based on the resistance level distribution of the F1 population, it was found that the hybrid offsprings of Finger (susceptible) × Ciputao0940 (resistant) showed continuous variation in anthracnose resistance, which was a typical quantitative trait controlled by polygens, and the phenotypic distribution of disease resistance identification results showed a trend of partial normal distribution, which could be analyzed by QTL localization. In the positioning of QTL related to grape resistance to anthracnose, the interval or site of LOD≥3.0 was used as the threshold value for QTL, and when the above conditions were met, the site corresponding to the highest LOD value in the interval was considered to be one QTL of grape anti-anthracnose. In this experiment, a QTL interval associated with grape anthracnose resistance was detected on the 8th linkage group, and the locus with the highest LOD value in this interval was located at 140.682 cM, and the tightly linked label was Maker1675910, which could explain the 14.7% of the phenotypic variation. Based on the gene annotation results of the QTL locus interval, 15 resistance- related genes were screened out, and they were hypothesized to play a role in grape anthracnose resistance. 【Conclusion】 The resistance level of different grape germplasms to anthracnose was clarified, one QTL site against anthracnose was located and 15 resistant-related genes were screened. © 2023 Journal of Fruit Science. All rights reserved.  相似文献   

17.
AIMTo investigate the effects of Yangjing-Zhongyu decoction on the in vitro maturation and expression of platelet-derived growth factor subunit A (PDGFA) and platelet-derived growth factor receptor α (PDGFRα) of mouse oocytes. METHODSThe SPF female KM mice were given Yangjing-Zhongyu decoction, and the blood was collected to prepare serum. The serum containing Yangjing-Zhongyu decoction was used to culture immature oocyte-granulosa cell complexes. After the in vitro culture, the oocyte maturation rate, fertilization rate and cleavage rate were observed and calculated, and the expression of PDGFA and PDGFRα in the oocytes at protein and mRNA levels was determined by West?ern blot and real-time PCR. RESULTSYangjing-Zhongyu decoction increased the in vitro maturation rate and fertil?ization rate of the oocytes (P<0.05 or P<0.01), and down-regulated the protein and mRNA expression of PDGFA and PDGFRα (P<0.01). CONCLUSION Yangjing-Zhongyu decoction may promote the in vitro maturation of mouse oocytes by down-regulating the expression of PDGFA and PDGFRα.  相似文献   

18.
Summary

The influence of exogenously applied indole-3-butyric acid (IBA) on root and shoot development of leafy cuttings was analysed in Prunus cerasus P. canescens ‘GiSelA 5’, a dwarfing cherry rootstock, in two successive years. Compared to control cuttings, IBA application (4 g l–1 in 2003; 2.5 g l–1 in 2004) caused higher indole-3-acetic acid (IAA) accumulation in the cutting bases, but that did not influence the percentage of rooted cuttings, nor their survival in either year. However, IBA inhibited callus formation and, consequently, influenced the quality of the developed cuttings. Callus formation impeded root development, reducing the number of main roots, and inhibited the growth of the cuttings, reducing the average total length of shoots formed by individual cuttings. Callus formation was most reduced in the cuttings in the second experimental year, with high initial IAA concentrations.  相似文献   

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Summary

Four species of the genus Kalanchoë (Crassulaceae), K. peltata, K. laxiflora, K. tubiflora and K. marmorata, were regenerated from leaf explants by direct organogenesis. Each species was tested on 19 media, all based on MS-medium. One medium was without growth regulators, the remaining 18 contained a combination of auxin and cytokinin. Auxin was indole-3-acetic acid (IAA): 1.1, 2.3 or 4.6 μM (0.2, 0.4 or 0.8 mg l–1). Cytokinin was either 1-phenyl-3-(1,2,3-thidiazol-5-yl)urea(TDZ): 1.1, 2.3 or 4.5 μM (0.25, 0.5 or 1.0 mg l–1), or 6-benzylaminopurine (BAP): 1.1, 2.2 or 4.4 μM (0.25, 0.5 or 1.0 mg l–1). For each species an optimum level of growth regulators were obtained. One medium, called K22, containing 0.5 mg l–1 TDZ and 0.04 mg l–1 IAA, showed good shoot-generating capacity with all four species. Shoot elongation proved to be a problem only with K. marmorata. This could be bypassed by transferring shoots to a gibberellic acid (GA3)-containing medium, or by ventilating the containers. Shoots were rooted on MS-medium and rooted shoots were transferred to soil. K. laxiflora failed to root, but plantlets produced on the leaves were easily used for vegetable proliferation of the regenerated shoots. Eight additional Kalanchoë species and four species from other genera of Crassulaceae: Crassula, Echeveria and Sedum, were tested for regenerative capacity on K22-medium. From four Kalanchoë species and three other species, regenerated plants were established in soil. These results suggest that this medium has a high regenerative capacity within the Crassulaceae. No close dependency was found between systematic position and ability to regenerate on this medium.  相似文献   

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