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1.
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   

2.
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   

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.
5.
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   

6.
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   

7.
8.
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   

9.
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   

10.
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   

11.
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   

12.
【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   

13.
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   

14.
Microscopical examination demonstrated that Tricholoma giganteum basidia bear 4 basidiospores. Mating tests revealed that T. giganteum has a tetra-polar, heterothallic mating system. New types of factor B (Br) occurred as a result of recombination within the B-type mating factor.  相似文献   

15.
以观赏凤梨“丹尼斯”为试材,研究了不同催花剂处理对观赏凤梨“丹尼斯”内源激素含量的影响.结果表明:不同催花剂处理后,“丹尼斯”凤梨植株体内的IAA含量呈下降趋势,ZRs含量呈增加趋势.说明催花剂能抑制内源IAA的产生,促进内源ZRs的产生.以乙炔气体饱和溶液处理效果最明显.  相似文献   

16.
The distribution of dry matter between the different bulblets of tulip is not markedly influenced by either changes in leaf area or the position of the leaf. On the contrary, total bulb yield is strongly affected.A reduction factor, Sc, for incomplete soil coverage, when the leaf area index (LAI) is less than 4, normally used for evaluation of planting density effects, can also be used for the effects of defoliation on dry matter increase. This LAI-dependent factor shows a distinctly asymptotic pathway closely resembling
Sc=PactPpot=1?e?k1LAI
where k ~ 0.6 and in which Pact is the actual measured dry weight increase and P?pot the potential net dry weight increase for a closed canopy.  相似文献   

17.
2Results and Analysis2.1Essential amino acid composition of proteinfromspores ofA.blazeiJ1and J3Essential amino acid compositions ofprotein fromspores ofA.blazei,strains J1andJ3,are shown in Table1(see the Chineseversion).Ile,Leu and Phe+Tyr levels inprotein from J3spores were113.6%,16.7%and5.0%higher,respectively compared withthe corresponding protein fromJ1(P<0.05),whereas the content of other amino acids were6%-35%higher in protein fromJ1.The totalessential amino acid content of prot…  相似文献   

18.
19.
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   

20.
AIM: To study the effects of panax notoginseng saponins (PNS) on the content of triglyceride (TG) and the mRNA expression of liver X receptor α (LXRα) in steatotic hepatocyte L02.METHODS: The cells of hepatocyte L02 were cultured with 50% bovine calf serum for 48 h and a model of steatosis of hepatocytes was established. The appropriate concentrations of PNS on steatotic hepatocytes were detected by MTT assay. The cells were divided into 5 groups: normal control group, model group, spontaneous recovery group, low concentration of PNS group (10 mg/L) and high concentration of PNS group (50 mg/L). Meanwhile, hepatocytes in model group were continuously cultured by RPMI-1640 medium containing 50% bovine calf serum while others were cultured by RPMI-1640 medium containing 10% bovine calf serum. After 24 h, the lipid droplets in the cells stained with oil red O were observed under microscope, the intracellular TG levels were determined by automatic biochemical analyzer and the mRNA expression of LXRα in hepatocytes was examined by RT-PCR. RESULTS: Compared to normal control group, Oil red O staining presented numerous orange-red or red lipid droplets in the cytoplasm of human L02 hepatocytes in model group. The content of TG in model group were significantly increased (P<0.01). After treated with PNS for 24 h, the content of TG in PNS treatment groups was significant decreased than that in spontaneous recovery group (P<0.05), especially in low concentration of PNS group (P<0.01). The accumulation of lipid droplets in low concentration of PNS group was decreased significantly. Compared to normal control group, the mRNA expression of LXRα in model group was significantly up-regulated (P<0.01). Compared to spontaneous recovery group, the mRNA expression of LXRα in PNS treatment groups declined in different levels, especially in low concentration group (P<0.05).CONCLUSION: The deposition of lipid in hepatocytes might be related to the high expression of LXRα mRNA. PNS decreases the content of TG in steatotic hepatocytes and promotes the recovery of hepatocyte steatosis by downregulating the mRNA level of LXRα.  相似文献   

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