Kaki Cv Research Articles

Antioxidant and antigenotoxic activities of different parts of persimmon (Diospyros kaki cv. fuyu) fruit

This study was conducted to determine the antioxidant activities and the antigenotoxic effects of acetone, ethanol, methanol and water extracts from four different parts (calyx, seed, peel and flesh) of persimmon fruits. Antioxidant activities were evaluated by DPPH (1,1-diphenyl-2-picryllhydrazyl) radical scavenging activity (RSA), ABTS (2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammononium salt) RSA and reducing power (RP). Seed and calyx extracts showed significantly (p < 0.05) higher antioxidant activities and phenolic contents than peel and flesh extracts. This study also showed that ethanol was more effective on the extraction of antioxidant compounds from persimmon compared to other solvents. The antigenotoxic effects of the persimmon extracts on DNA damage induced by H2O2 in human leukocytes was evaluated by Comet assay. All persimmon extracts inhibited DNA damage induced by 200 µM of H2O2. Especially, calyx and seed extracts showed stronger inhibition activity than peel and flesh extracts. Therefore, these results suggest that persimmon extracts may have beneficial effects on oxidant and protective effect against oxidative DNA damage. Key words: Persimmon extract, antioxidant activities, antigenotoxic effect.

Root storage of nitrogen applied in autumn and its remobilization to new growth in spring of persimmon trees ( Diospyros kaki cv. Fuyu)

This study was conducted to understand the effect of N supply in autumn on its uptake and distribution in tree parts and the utilization of reserve N the following year in persimmon trees ( Diospyros kaki cv. Fuyu). The treated trees received 22.5-g N each for two successive years as a 3.5% urea solution from September 18 at 5-day intervals. Trees absorbed about 30% on average of the N applied in autumn. Sixty four to 83% of the N absorbed in autumn was in perennial parts, and 65–72% of that was in roots. Total N in perennial parts of the tree fertilized with N increased by over 4.28 g while leaf N changed little during senescence, indicating that the reserve N was constituted mostly by the N absorbed in autumn. Total N in the new growth was about the same as the amount of N declined in spring from perennial parts, indicating that there was little contribution by soil N to sustain new growth. Total dry weights of new growth the following year in a with-N tree were greater by over 34 g than those in a without-N tree.

Penicillium expansum에 의한 감 푸른곰팡이병 발생

A fruit rot of sweet persimmon(Diospyros kaki cv. `Fuyu`) that infected with blue mold was found during the storage and transport in Jinju Gyeongnam Province, Korea. Fruit surfaces that infected with the fungus were formed water soaked lesion at first then gradually colonized with the fungus and formed mycelial mats. From the point of infection, fruits become sunken and mostly ruptured. The pathogenic fungus was isolated from infected fruits and cultured on potato dextrose agar. The colonies of the pathogenic fungi were white at frist then became greyish green on malt extract agar. Conidia were ellipsoidal and in size. Phialides were ampulliform, verticilate of 3-7, in size. Metulae were verticils of 2-4, smooth, in size. Ramuli were groups 1-3, smooth, in size. Rami were groups 1-2, in size. Stipes were septate, smooth, thin walled, in size. Penicilli were mostly quaterverticillate. Based on the cultural and mycological characteristics as well as pathogenicity test on host plants, the fungus was identified as Penicillium expansum. This is the first report on the blue mold of sweet persimmon(Diospyros kaki) caused by P. expansum in Korea.

Alternaria alternata에 의한 단감 검은점무늬병 발생

2002년 경남 창원시 동읍 단감 저온 저장고에 저장중인 과실에서 검은점무의 증상이 심하게 발생하였다. 병징은 과실표면에 검은색 둥근 반점이 생기고 병반부위가 확대되면서 그 위에 암갈색의 곰팡이를 형성한다. 병반부위를 절단해 보면 감염된 표피에서부터 시작하여 과육내부까지 갈색으로 변색되고 스폰지 모양으로 부패되어 상품성이 전혀 없다. 병원균의 분생포자는 난형, 곤봉형, 서양배형이고 드물게 타원형도 있으며 횡격막이 3∼5개, 종격막이 1∼2개 있다. 색깔은 연한 갈색 또는 금색을 띄는 갈색이고 크기는 12∼46<TEX>${\times}$</TEX>6∼12<TEX>$\mu\textrm{m}$</TEX>이었다. 분생포자경은 연한 담갈색이고, 크기는 42∼95<TEX>${\times}$</TEX>3∼5 <TEX>$\mu\textrm{m}$</TEX>이었다. 균사생육적온은 25∼3<TEX>$0^{\circ}C$</TEX>이었다. 단감 저장중 과실에 발생한 병징과 병원균의 균학적 특징을 조사한 결과, 이 병을 Alternaria alternata (Fr.) Keissler에 의한 단감 검은점무의병으로 명명하고자 제안한다. Black spot disease on sweet persimmon (Diospyros kaki cv. Fuyu) was found from the farmer's refregerated ware house located in Dong-eup, Changwon city, Gyeongnam province, Korea, 2002. The typical symptoms of the disease was appeared black spot on surface of fruits. Colonies of causal fungus were developed velvety and later turned olivaceous black to sooty black in color on PDA. Conidia were pale brown to golden brown in color and ovoid, obclavate to obpyriform, rarely ellipsoid in shape. and were 12∼46 <TEX>${\times}$</TEX> 6∼12 <TEX>${\mu}{\textrm}{m}$</TEX> in size. Septa were 3∼5 transvers, 1∼2 longitudinal or oblique. Conidia were mostly beakless and generated chains by means of secondary conidiophores. Conidiophores were pale to mid brown in color and 42∼95 <TEX>${\times}$</TEX> 3∼5 <TEX>${\mu}{\textrm}{m}$</TEX> in size. The optimum temperature for growth of the fungus was about 25∼3<TEX>$0^{\circ}C$</TEX>. This is the first report on the black spot of sweet persimmon caused by Alternaria alternata (Fr.) Keissler in Korea.

Bruising injury of persimmon ( Diospyros kaki cv. Fuyu) fruits

This study was performed to monitor the deterioration of bruised persimmon ( Diospyros kaki cv. Fuyu) fruits. Freshly harvested fruits were bruised by dropping them from a height of 50 cm onto a steel board and then stored at 0 or 20 °C in temperature controlled chambers for up to 4 weeks. Immediately after the bruising, no visible injury on the fruits was evident, but the fruits deteriorated rapidly during storage. The skin tissues of the fruits stored at 20 °C became more reddish with the duration of the storage, but no such changes were found with the fruits stored at 0 °C. The increase in redness of the skin tissues appeared to be associated with storage temperature, but not with the bruising. The skin tissues also became darker when stored at 20 °C than at 0 °C and this tendency was more obvious with the bruised fruits. Flesh firmness decreased rapidly during storage except for the non-bruised fruits stored at 0 °C. Even the non-bruised fruits rapidly lost their flesh firmness at 20 °C. No significant changes in lipid peroxidation, as expressed by malondialdehyde production, were found between the bruised and the non-bruised fruits during the storage either at 0 °C or at 20 °C. This implies that the fruit deterioration caused by bruising is not due to the consequences of lipid peroxidation. Polyphenol oxidase activity increased more rapidly in the bruised fruits than in the non-bruised fruits during storage. The bruising had more effect on increasing polyphenol oxidase activity than did the storage temperature. Although the increase in polyphenol oxidase activity appeared to be associated with the visual deterioration of the bruised fruits, it did not exactly correspond to the physical deterioration. These results indicate that polyphenol oxidase is not the only factor influencing the deterioration associated with bruising. Cell wall hydrolases are currently being assayed to determine if they also contribute the deterioration following bruising.

Transformation of persimmon with a pear fruit polygalacturonase inhibiting protein (PGIP) gene

Persimmon ( Diospyros kaki cv. Jiro) was transformed with the gene encoding the pear fruit ( Pyrus communis) polygalacturonase inhibiting protein (PGIP) using Agrobacterium tumefaciens EHA101. Two plasmid constructions were used for transformation; pDU94.0928 containing chimeric genes of PGIP, GUS and NPTII in its T-DNA region, and pYS95.091 containing only the GUS and NPTII sequences (control transformations). Among 165 callus lines obtained from infection by A. tumefaciens with pDU94.0928, 15 showed GUS activity. A PGIP gene fragment of 132 bp was amplified by PCR in nine of 15 callus lines. Shoots were regenerated from three of the nine PGIP-containing callus lines. The transformation of the regenerated shoots was confirmed by PCR and Southern blot analyses using NTPII, GUS and pear PGIP probes. PGIP expression in shoot tissues was analyzed by western blot analysis. The protein expression was observed in all three shoot lines regenerated from transformed calli with the PGIP gene. Fungal PG activity was inhibited by crude extracts from shoots transformed with the PGIP gene substantially more than by those from the control transformants obtained from the transformation with pYS95.091.

Penicillium crustosum에 의한 감 푸른곰팡이병 발생

A severe fruit rot of Persimmon (Diospyros kaki cv: Fuyu) was occurred during the storage and transport that infected with blue mold in Sweet Persimmon Experiment Station, Gyeongsangnam-do Agricultural Research and Extension Services, Korea. Fruit surfaces were infected with the fungus first and the colonized fungus formed mycelial mats. From the point of infection, fruits become collapsed and mostly ruptured. The pathogenic fungus from infected fruits was isolated and cultured on PDA. Colony color of the fungus was white at frist than became green on Malt Extract Agar and Czapek Yeast Extract Agar. Conidia were ellipsoid subglobose and 2.63.8 2.43.8 in size. Stipes were 86320 2.84.3 in size. Rami were 7.532.6 2.64.2 in size, Ramuli were 12.414.8 3.23.8 in size, Metulae were 8.913.6 2.84.6 in size. Phialides were ampulliform, 8.212.4 2.33.6 in size. Based on the cultural and mycological characteristics and pathogenecity test on host plants, the fungus was identified as s, This is the first report on the blue mold of Persimmon (Diospyros kaki) caused by P. crustosum in Korea.

Quantitative magnetic resonance imaging of ‘Fuyu’ persimmon fruit during development and ripening

Qualitative and quantitative proton magnetic resonance imaging techniques were applied to persimmon ( Diospyros kaki cv ‘Fuyu’) fruit during development and post-harvest ripening. Spin-lattice (T 1) relaxation times in mesocarp parenchyma and vascular tissue exhibited a sigmoidal pattern of increase leading to commercial harvest, but declined abruptly during ripening, 2.5 weeks after picking. T 1 times in parenchyma tissue were 1000 and 2100 ms in fruitlets, and at commercial harvest, respectively. T 1 times in vascular tissue were consistently shorter than those in parenchyma tissue by 300 to 600 ms. In contrast, spin-spin (T 2) relaxation varied over a narrow range during development, i.e., 82 to 106 ms, and 59 to 73 ms, for parenchyma and vascular tissue, respectively. During ripening, T 2 measurements increased smoothly, commencing one week after harvest. Dry matter, water content, skin color, water-soluble tannins, soluble solids, and mineral and carbohydrate composition was also determined in companion fruit. No obvious associations linking physico-chemical and MR parameters were established, implying that the changes in relaxation measurements observed in ‘simple’ fruit systems can not be rationalised without recourse to more complex investigations involving SEM and different NMR spectroscopic and imaging techniques.

Production of somatic hybrids between Diospyros glandulosa and D. kaki by protoplast fusion

Interspecific somatic hybrids between Diospyros glandulosa (2n=2x=30) and D. kaki cv. Jiro (2n=6x=90) were produced by electrofusion of protoplasts. Protoplasts were isolated from calli derived from leaf primordia, fused electrically, and cultured by agarose-bead culture using a modified KM8p medium. Flow cytometry revealed that the nuclear DNA content was the sum of those of D. glandulosa and D. kaki cv. Jiro in 149 of the 166 calli obtained. RAPD analysis showed that the 149 callus lines yielded specific bands for both D. glandulosa and D. kaki cv. Jiro and further confirmed that they were interspecific somatic hybrid calluses. Shoots were regenerated from 63 of the 149 interspecific hybrid calluses. Chloroplast DNA analysis by PCR-RFLP, flow cytometric determination of nuclear DNA content, and RAPD analysis revealed that the 63 interspecific hybrid shoot lines contained the nuclear genomes from both parents but only the chloroplast genome from D. glandulosa. Microscopic observation of root tip cells demonstrated that somatic chromosome number of the interspecific hybrids was 2n=8x=120.

Ploidy Level and Genome Size of Several Diospyros Species.

Callus cells induced from leaf primordia were used for a rapid and efficient determination of genome size and ploidy level of several Diospyros spp. including D. kaki. Nuclear DNA contents of nine Japanese persimmon (Diospyros kaki Thunb.) cultivars and other 12 Diospyros species were estimated by flow cytometry. Compared to the known nuclear DNA contents of chicken red blood cells and tobacco leaf cells, genome sizes of hexaploid cultivars (2n=6x, x=15) of D. kaki were estimated to be 5.00-5.24 pg/2C and those of nonaploid (2n=9x) to be 7.51-8.12 pg/2C. Nuclear DNA content of another hexaploid species, D. virginiana, was 5.12 pg/2C and that of a tetraploid, D. rhombifolia, was 3.76 pg/2C. Nuclear DNA contents of all the diploid species tested, except for D. montana, fell in the range of 1.57-2.31 pg/2C. Although D. montana is a diploid, its genome size was 3.48 pg/2C and about the same size as that of a tetraploid, D. rhombifolia. There was a strong positive linear correlation between the ploidy levels and the genome sizes of Diospyros spp. tested, except for D. montana. In this study, chromosome number was also counted, using callus cells to determine if ploidy levels can be deduced from flow cytometry. D. kaki cv. Miyazakitanenashi was nonaploid with chromosome number of 2n=135, D. kaki cv. Jiro and D. virginiana were hexaploid with 2n=90, and D. rhombifolia was tetraploid with 2n=60, and the other species tested, including four species whose ploidy levels had been unknown, were determined to be diploid. The results agreed with the deduced ploidy levels from flow cytometry except for D. montana.

Reduction of chilling injury in the sweet persimmon `Fuyu' during storage by dry air heat treatments

Abstract Sweet persimmon fruit ( Diospyros kaki cv. Fuyu L.) were heat-treated with dry air at 34–50°C for durations of 0.5–10 h, cooled immediately, and stored for 6.5 weeks at 0°C in air. After storage, fruit were held for 3 days at 20°C, and evaluated for quality. Extreme chilling injury (flesh gelling) was observed in non-heated fruit. Associated with development of chilling injury was increased ethylene production 1 day after removal from storage, and decreased fruit firmness, juiciness, titratable acidity, and colour ( L value, hue and chroma) 3 days after removal from storage. Increasing the temperature of the hot air heat treatment (HT) progressively reduced flesh gelling and alleviated chilling injury. However, external and internal browning increased with greater HT temperatures and duration. Least chilling injury and external browning were observed at 47°C for 0.5–3 h. However, the levels of browning observed in these treatments are likely to be commercially unacceptable. Thus, although hot air HTs confer significant protection against low temperature damage to persimmon fruit, heat damage needs to be reduced before such benefits can be realised commercially.

Production of Interspecific Hybrids of Persimmon by Protoplast Fusion

Interspecific hybrids between Diospyros glandulosa (2n = 2x = 30) and D. kaki cv. Jiro (2n = 6x = 90) were produced by electrofusion of protoplasts. Protoplasts were isolated from calli derived from leaf primordia, fused electrically, and cultured by agarose-bead culture using modified KM8p medium. Relative nuclear DNA contents of calli derived from fusion-treated protoplasts were determined by flow cytometry. One-hundred-forty-nine of 166 calli obtained had the nuclear DNA content of the sum of those of D. glandulosa and D. kaki cv. Jiro. RAPD analysis showed that the 149 callus lines yielded specific bands for both D. glandulosa and D. kaki cv. Jiro and they appeared to be interspecific somatic hybrid calli. Shoots were regenerated from 63 of the 149 interspecific hybrid calli. PCR-RFLP of chloroplast DNA analysis, flow cytometric determination of nuclear DNA content, and RAPD analysis revealed that the 63 interspecific hybrid shoot lines contained nuclear genome from both the parents but only chloroplast genome from D. glandulosa. Microscopic observation of root tip cells confirmed that somatic chromosome numbers of the interspecific hybrids were 2n = 8x = 120.

Magnetic resonance imaging of persimmon fruit (Diospyros kaki) during storage at low temperature and under modified atmosphere

Abstract Effects of time and storage atmosphere on relaxation properties in persimmon fruit (Diospyros kaki cv Fuyu) were investigated by nuclear magnetic resonance (NMR) imaging during the five weeks following commercial harvest. There were two treatments (n = 4): one in which fruit were hermetically sealed in individual polyethylene bags (modified atmosphere or MA treatment), and another sealed in individual perforated bags (control). Fruit were stored at 7 °C for 4 weeks (conditions conducive to development of chilling-injury), before being removed to 20 °C for 3 days to simulate poststorage shelf conditions. Every week, and at the end of the shelf-life period, a series of 1H NMR images of median transverse and longitudinal planes were acquired from each fruit for calculation of spin-lattice (T1) and spin-spin (T2) relaxation times. Relaxation times associated with the flesh, vasculature and locules in transverse sections, and flesh from basal, median and distal regions of longitudinal sections, were significantly shorter in MA-treated fruit, although no T2 treatment difference was noted with vasculature. MA-treated fruit were further distinguished from controls in that all tissues exhibited a sharp increase in T1 (but not T2) relaxation between the second and third weeks in cold storage. Within a treatment, T1 times in flesh and locules were similar (ca. 1120 ms), and shortest in vascular tissue (1036 ms). T2 was a more sensitive indicator of tissue type (mean values of 71, 101 and 116 ms in the vasculature, flesh and locules of MA-treated fruit, respectively), than T1. However the relative ranking of flesh and locule tissues was time-dependent. There was no gradient in relaxation times between basal, median and distal regions of the fruit. Incipient stages of chilling-injury development were unable to be identified either by visual inspection of time-course images, or variation in relaxation properties. Our observations do indicate, however, that relaxation properties in fruit were strongly influenced by MA conditions. Increased concentrations of soluble metabolites arising from reduced respiration in MA-treated fruit is a possible mechanism consistent with these results, but not removal of a paramagnetic species like O2, where T1 values would be predicted to increase.

Purification and Some Properties of Acid Invertase of Persimmon Fruits

Single cells were prepared from mesocarp tissue of ripe persimmon (Diospyros kaki cv. Fuyu) fruits, and inter- or intracellular localization of acid invertase (AI, EC 3.2.1.26) was studied. AI was localized in the intercellular fraction (cell wall fraction). AI was isolated and purified from the cell wall fraction of ripe persimmon fruits by column chromatography on SE-53 cellulose and Toyopearl HW 55F. The specific activity of purified AI was 570 units per mg protein at 30°C. The molecular mass of AI was estimated to be 44 kDa by gel filtration over Sephacryl S-200 and 70 kDa by SDS–PAGE. The optimum pH of the activity for sucrose was 4.25. The purified enzyme hydrolyzed sucrose and raffinose but not melibiose. The enzyme had a Km of 3.2 mM for sucrose and a Km of 2.6 mM for raffinose. Silver nitrate (5 μM), HgCI2 (2 μM), p-chloromercuribenzoate (100mM), pyridoxamine (10mM), and pyridoxine (2.5mM) inhibited AI activity by 95, 85, 100, 41, and 300%, respectively.

Persimmon Pectinmethylesterase: Extraction and Variation during Ripening

ABSTRACTThe optimum conditions for the extraction of pectinmethylesterase (PME) from persimmon fruit (Diospyros kaki cv. Taubaté) were found to be: 1.6M NaCl + 1% (v/v) Triton X‐100 + 5% (w/v) bovine serum albumin (BSA) for astringent fruit and 0.2M NaCl for nonastringent fruit. During ripening with ethephon, PME showed a close variation with respiration up to the climacteric peak when fruits became soft and nonastringent. Untreated astringent fruits showed little variation in either respiration or PME activity.

カキ&amp;lsquo;富有&amp;rsquo;果実の肥大生長と果柄部維管束の発達について

This experiment was conducted to reappraise more thoroughly the development of Japanese persimmon fruit, Diospyros kaki cv. Fuyu, by measuring the growth rate and the relative growth rate (RGR) of fruit diameter and weight, in relation to the vascular development of the fruit stalk.Cumulative diameter and weight increases have a double sigmoid pattern corresponding with changes in growth rate. Fruit development was classified into three distinct stages. Stage I was completed by early August, 10 weeks after anthesis. The increase to a peak in the growth rate of fruit diameter preceded by several weeks the peak in the growth rate of fresh fruit weight. Furthermore, the maximum rate of fresh weight growth occurred one week earlier than the maximum rate of dry weight growth. The whole fruit declined in dry matter percentage during the middle of this period when fruit diameter increased rapidly. The low percentage of dry matter in the fruit lasted during the period of July, when the growth rate of fresh weigh typically increased. On the other hand, the fruit increased in dry matter percentage during the two weeks in the early period of stage I, accompanying tannin cell development.During stage II, in which the overall growth rate slowed down markedly, the fruit increased in dry matter percentage. Both seed weight and the dry matter percentage of seed increased markedly during this stage.During stage III, a period of vapid growth, fruit continued to grow and to increase in dry matter percentage for as long as it was left on the tree. Initially in stage III, a rapid increase of fruit diameter commenced almost simultaneously with the weight increase.The rate of fruit diameter increase was higher in stage I than in stage III, but the rate of fresh weight growth was nearly the same in stage I and III. Contrarily, the dry weight increase in stage III was markedly higher than in stage I.There appeared to be little difference in the fruit growth curves among fruits which had different numbers of seeds, although there was a significant positive correlation between seed and fruit weight until July, during the early stage of fruit development.The maximum peak of the RGR of fruit diameter and fruit weight appeared several days after full bloom, and a small RGR peak appeared again during the ripening stage.The growth of the stalk diameter increased markedly during stage I of the fruit development, and lasted until mid-August. The differentiation of vascular tissue (transverse section)in the fruit stalk had already begun one month before blooming. However, this development was only slight: xylem vessel diameter averaged about 9μm and phloem differentiation had progressed enough to display a large nucleus. Thereafter, vascular tissue (xylem vessels, sieve tubes and companion cells) was developed strikingly until blooming, and continued to grow markedly until approximately 4 weeks after blooming. Although the growth of vascular tissue appeared to slow down gradually during the decelerated period of fruit growth, it increased again duting the ripening stage. The development of the vascular bundle in the stalk region corresponded to the fruit growth.

カキ&amp;prime;富有&amp;prime;樹の新しょうと葉の発育過程について

The growth of vegetative organs in Japanese persimmon, Diospyros kaki cv. Fuyu, was investigated by examining the growth rates of the current shoots and leaves. Leaf growth was related to development of the tissue systems.The development of current shoots, in terms of elongation and weight, was different according their position on the mother shoot (two year old branches), with distal shoots displaying greater development than proximal shoots. The rate of both elongation and growth in fresh weight of the shoots was highest in early May, and declined rapidly thereafter. The rate of dry weight growth peaked in mid-May.Leaf area increased markedly during the early stage of shoot development (mid-May), and the rate of leaf area growth declined in late May. The increase in fruit diameter growth typically commenced in mid-June, one to two weeks after the leaf area maximum was attained. The growth of basal leaves both began and finished earlier than that of upper leaves, even though the surface areas of leaves in upper positions were generally larger. The maximum growth rate in whole-leaf dry weight appeared in late May, thereafter decreasing throughout the growing season.Shoots began to decline in dry matter percentage immediately after the start of shoot elongation, until mid-May. Thereafter the dry matter percentage of the shoots increased markedly until early July, and continued to increase gradually until the ripening stage. On the other hand, the dry matter percentage of the leaves was low during the period from leaf opening to mid-May, and increased gradually until early July. The maximum growth rate of the fruit, in terms of fresh weight, appeared in mid-July, about two weeks behind the maximum in the dry matter percentage of the leaf.Development of the mesophyll (palisade and spongy tissue) was almost completed by mid-June, when the leaf surface area on the shoots had attained a maximum. The development of vascular tissues, especially xylem, in both the petiole and midrib began simultaneously after leaf opening, and was nearly finished by mid-June, about two weeks after the maximum in leaf area.