Changes of abscisic acid and its metabolite during development of apple fruit

Summary

Free and conjugated abscisic acid (ABA) and phaseic acid (PA) concentrations in the seed and pulp of apples (Malus pumila Mill. cv. Tsugaru) and ABA metabolism in the fruit after cis-(+)-ABA application were investigated. In the seed, the levels of cis- and trans-ABA and conjugated cis- and trans-ABA showed a general increase towards harvest, except for the decrease of cis-ABA at 131 d after full bloom (DAFB) (harvest). PA levels reached a peak at 41 DAFB, then decreased until harvest. The levels of free ABA in the seed were higher than those in the pulp. In the pulp, the levels of cis-ABA increased gradually from 20 DAFB and rapidly from 111 DAFB towards harvest. The levels of trans-ABA and conjugated trans-ABA also showed similar changes to cis-ABA, i.e. increased steeply from 111 DAFB. In contrast, the level of conjugated cis-ABA was the highest at 20 DAFB, then fell rapidly until 111 DAFB and then increased again towards harvest. PA showed the highest level at 20 DAFB, then decreased gradually until 111 DAFB and then increased again towards harvest. It is therefore assumed that not only cis-ABA but also its metabolite may be associated with the ripening of apple fruit. Cis- and trans-ABA and conjugated cis- and trans-ABA concentrations in cis-(+)-ABA treated fruit increased significantly on 11 d after ABA application (122 DAFB). However, at 20 d after cis-(+)-ABA application, only trans-ABA and conjugated trans-ABA showed higher levels than those of the untreated control, while the levels of cis-ABA and conjugated cis-ABA fell to the same levels as the untreated control. PA levels did not show significant increase on 11 and 20 d after cis-(+)-ABA application. These results suggest that cis-(+)-ABA treated exogenously to apple fruit may eventually metabolize to trans-ABA, conjugated trans-ABA and further metabolites.     

Electron-microprobe analysis of apple fruit tissues affected with bitter pit

The concentrations of the mineral elements K, Ca, Mg, P, S and Cl were compared in pitted and sound tissues of mature fruits of the apple cultivars ‘Akane’, ‘Reine des Reinettes’ and ‘Idared’ using an electron microprobe. Mg, Ca and to a lesser extent S were always present in higher concentrations in pitted areas than in non-pitted ones, in the ratio of 3.0 to 14.4 for Mg and 3.1 to 7.9 for Ca. The K concentration in pitted tissues was variable showing no significant difference in ‘Akane’, and an increase or decrease in ‘Reine des Reinettes’ and ‘Idared’, respectively. P and Cl concentrations were also variable. Serious perturbations were found in the ionic content of the pitted tissues affecting several elements implicated in essential physiological processes.     

A modified chemiluminescence method for hydrogen peroxide determination in apple fruit tissues

Hydrogen peroxide (H₂O₂) is one of the important by-products produced by plant and fruit tissues during normal metabolism as well as under stress conditions. Evidence suggests that it is actively involved in many physiological activities in plants, including ripening, senescence and the development of disorders. Quantitative measurement of H₂O₂ in fruit has been a challenge due to variations in methodologies, and their sensitivities and interferences present in plant samples. Among the currently used methodologies, chemiluminescence (CL) is one of the most promising, due to its high specificity and sensitivity. However, direct application of CL methods developed for leaf analysis is not suitable for fruit, especially fruit peel tissues, possibly due to interfering compounds in fruit tissues. In this study, evaluation of the efficiency of removal of interfering compounds by PVP, PVPP and activated charcoal revealed that the PVPP is the most effective compound to remove the interference. This modified protocol can measure H₂O₂ content in apple peel and flesh tissues. ‘Red Delicious’ apple peel and flesh tissues were measured with amount of 1.48 and 1.03 μmol/g FW, respectively. The established protocol can also be used for a wide variety of tissues in addition to apple fruit, including strawberry tissues (fruit, calyx and leaves) and spinach leaves. This protocol was applied to determine the H₂O₂ concentration in 1-MCP and DPA treated apples after 5 months of storage, but no significant difference in H₂O₂ in those samples was found. Direct comparison of CL with a commercial hydrogen peroxide measurement OXIS kit was also made. The challenges to accurately assay H₂O₂ in fruit/plant tissue were discussed.     

脆肉梨果实成熟过程中质地性状的变化

【目的】探讨脆肉梨成熟过程中不同时期、果实不同部位质地性状的差异和变化规律。【方法】以脆肉梨品种‘华酥’和‘圆黄’为试材,采用食品物性分析仪质地多面分析法(TPA)和穿刺试验,测定果肉脆度、硬度、黏着性、弹性、胶黏性、咀嚼性和果皮硬度等7个质地性状。【结果】各质地性状在梨果实成熟过程中均发生显著变化,而且果实萼部、中部和梗部3个部位的质地性状均存在差异;除黏着性与其他参数间的相关性较差之外,果肉脆度、果肉硬度、弹性、胶黏性、咀嚼性和果皮硬度之间均呈极显著正相关。【结论】首次明确了在梨果实成熟过程中各部位质地性状的变化规律,可以为梨适宜采收成熟度的确定提供理论依据。     

Size factors in apple fruit

Eight ‘Golden Delicious’ apple trees on an experimental plot were systematically thinned to give different numbers of fruit per spur, per branch, and per tree. At harvest, fruits were weighed individually and their positions on spurs and branches noted. Trunk and branch girths were measured.Mean fruit weights were not significantly affected by the presence of several fruits on a spur, or by the degree of local crowding on branches, compared with the general mean for the whole tree. However, mean fruit weight varied between trees, depending on the number of fruits carried per unit of trunk girth of cross-sectional area.μ (mean fruit weight) = a — bN (number of fruit per unit trunk dimension)The distribution of fruit weights on each tree can be regarded as normal and on the 8 trees examined, standard deviations did not differ significantly. An equation was derived relating total crop per tree and fruit-size distribution to trunk dimensions and fruit number, both of which were variable from tree to tree, involving 2 coefficients of the mean size equation and the standard deviation of the weight distribution, which seem to be constant for the 8 trees under the prevailing conditions.Using the equations, it could be shown that although fruit thinning would increase the proportion of larger fruit in the crop, in only one case would careful thinning have increased the total weight of larger fruit.     

锦橙果实发育过程中香气成分的变化

为了研究锦橙果实发育过程中香气成分的组成及变化,使用气相色谱-质谱联用仪分析了10月、11月、12月、翌年1月的锦橙鲜果的挥发性成分,分别检测到47,50,57,46种成分,主要成分为烃类、醛类、醇类和酯类.挥发性物质的总峰面积以及烃类、酯类在12月的果实中达到最大,反式-2-己烯醛、反式-2-己烯-1-醇、顺式-3-...     

苹果果实日烧的控制

论述了苹果果实发生日烧的原因、规律及危害。指出气温是发生日烧的最主要因素,查明其临界值为30～32℃。同时介绍了防止苹果日烧的技术：园艺措施、喷雾冷却、果实套袋、使用遮阴布。     

榛果发育过程中主要营养成分的变化(英文)

以杂种榛优良品系82-11,84-237和84-402为试材,采用动态监测的方法,研究果仁发育过程中营养成分的变化,并分析了营养成分和矿质元素的相关性。结果表明,还原糖的含量前期呈下降趋势后期略有回升;蔗糖的含量呈上升趋势,在果仁成熟时成为主要的可溶性总糖;可溶性总糖在果仁发育期呈下降趋势,从果仁充实期到果仁充分成熟,含量逐渐升高;淀粉的含量呈上升—下降—平稳—上升趋势;粗脂肪和粗蛋白质的含量逐渐升高,呈明显累积趋势。果仁中蔗糖和可溶性总糖的积累主要在果仁发育的后期,粗脂肪和粗蛋白质的积累主要在果仁发育的前期和中期。果仁发育中,粗脂肪含量和氮素,磷素以及钾素呈极显著的正相关关系。     

苹果凹果类病毒(ADFVd)的检测与序列分析

采集新疆焉耆地区的老果园的苹果树枝条、叶片和韧皮部,利用自行设计的方法提取总RNA,根据GenBank中的X99487序列设计引物,利用RT-PCR技术扩增出苹果凹果类病毒(ADFVd)特异条带,通过回收克隆测序,结果表明,获得的7条序列,有5条同源性很高,均在98%以上,另外2条的同源性只有85%左右,这7条序列均已在GenBank中登录(登录号:EU031497_EU031503)。在此基础上利用插入ADFVd目的DNA的质粒为模板,成功合成了地高辛标记的cDNA探针,该探针能很好地用于ADFVd的检测。同时利用原位RT-PCR技术,做了进一步检测,证明苹果叶片中有苹果凹果类病毒存在,主要分布在叶肉细胞的细胞核中。     

Metabolism of endogenous nitric oxide during growth and development of apple fruit

Nitric oxide (NO) is a key signaling molecule in different physiological processes of plants. To study the metabolism of endogenous NO in growth and development of apple fruit under normal physiological conditions, the changes of several relative components of NO metabolism including the contents of NO, l-arginine, S-nitrosothiols (RSNOs) and nitrite plus nitrate, the activities of l-arginine-dependent nitric oxide synthase (NOS) and nitrate reductase (NR) were analyzed using vegetal ‘Gold Delicious’ and ‘Fuji’ apples as tested materials. The endogenous NO and l-arginine contents, as well as the l-arginine-dependent NOS activity in young fruit reached the highest value. The NOS activity was dependent on l-arginine and β-NADPH, and inhibited by a well known NOS inhibitor. The NR activity in apple fruit had not been detected. Endogenous NO production depended on l-arginine-dependent NOS but not NR. The content of RSNOs tended to peak in the fruit enlarging period and then declined. Similarly, the nitrate content increased in early stage of fruit growth, but in late stage, it undulated greatly. Compared to RSNOs and nitrate, the change of nitrite content was in accordance with that of endogenous NO. In general, RSNOs and nitrite could reflect the removal mechanism of NO relatively well.     

油红梨（Pyrus ussuriensis）果实后熟过程中香气成分的变化

通过顶空固相微萃取结合气相色谱质谱联用技术分析油红梨果实后熟不同时期挥发性组分。后熟0d、5d及10d时分别检测出11、26和33种挥发性成分,主要为酯类、醛类、醇类及萜类物质。各种挥发性物质在不同的后熟时期种类及绝对含量均为升高的趋势,尤其是酯类组分的增加;35种挥发性组分中共检测出7种特征香气组分,分别为己醛、E-...     

不同品种杏果实发育过程中类黄酮、总酚和三萜酸含量及抗氧化性研究

【目的】探讨不同品种杏果实发育过程中类黄酮、总酚、三萜酸含量的差异及与抗氧化活性的关系。【方法】以‘金太阳’‘凯特’‘华县大接杏’‘沙金红’‘金香’‘早金艳’等6个杏品种为试材,对不同品种杏果实发育过程中类黄酮、总酚、三萜酸的含量及清除羟基自由基(·OH)、DPPH自由基(DPPH·)和超氧阴离子自由基(·O2-)的能力进行分析测定。【结果】1.供试各品种杏果实中类黄酮、总酚、三萜酸含量均在果实发育早期(花后30 d)最低,其后随着果实的发育呈先上升后下降趋势。2.不同品种杏果实发育过程中类黄酮、总酚和三萜酸含量存在极显著差异(P0.01)。‘华县大接杏’在花后54 d类黄酮和总酚含量均达到最高,‘沙金红’在花后68 d三萜酸含量达到最高。3.供试杏果实的类黄酮、总酚及三萜酸的含量与抗氧化活性均存在相关性,其中杏果实中类黄酮和总酚的含量呈极显著正相关(r=0.882,P0.01);杏提取物清除·OH的能力和清除·O2-的能力呈显著相关(r=0.376,P0.05)。类黄酮、总酚含量与杏果实提取物清除DPPH·的能力呈极显著正相关(r=0.488、0.608,P0.01);三萜酸含量与杏果实提取物清除·OH的能力呈极显著正相关(r=0.494,P0.01)。【结论】不同品种杏果实发育过程中类黄酮、总酚含量与杏果实提取物清除DPPH·的能力呈显著正相关,三萜酸含量与杏果实提取物清除·OH的能力呈极显著正相关,说明类黄酮、总酚和三萜酸是杏果实中主要的抗氧化活性成分。‘华县大接杏’具有较高的类黄酮、总酚含量和清除DPPH·的能力,‘沙金红’具有较高的三萜酸含量和清除·OH的能力,均是功能性杏果及杏加工制品选择的理想品种。     

Phenolics concentration and antioxidant capacity of different fruit tissues of astringent versus non-astringent persimmons

Astringent and non-astringent persimmon fruits were compared for phenolic compounds, and their antioxidant capacity was studied in both peel and pulp. Fruits that were astringent generally had significantly higher concentrations of phenolics and greater capacities in either tissue. Pulp from astringent persimmons had more phenolics and higher capacity whereas the same was true for peels from non-astringent fruits. Among the methods tested for determining antioxidant capacity (ABTS, DPPH, FRAP, TBARS, SRSA, and HRSA), ABTS showed the best correlation with phenolics concentration while HRSA assays were not sufficiently sensitive to distinguish among genotypes or between fruit tissues. Therefore, we suggest that, for monitoring antioxidant capacity in persimmon, the ABTS method is most suitable.     

Botryosphaeria dothidea在苹果果实上的侵染过程(英文)

对Botryosphaeria dothidea通过皮孔侵入果实的过程进行了光学显微镜和扫描电镜观察,发现接种后2d分生孢子完成萌发和附着胞形成过程。接种后10d,菌丝体在皮孔表面缓慢生长。从20￣30d菌丝体加速扩展并形成几个分枝,通常从皮孔外围侵入果实,但仅限于皮孔表面组织。从40～50d,菌丝体扩展更为繁茂,一些菌丝开始突入皮孔的第2层组织。接种皮孔中可检测到多聚半乳糖醛酸酶(PG),但活性比对照高。皮孔有3层,第1层为含果胶的死组织,易被病菌侵染降解,底部的第3层非常坚固,是阻止病菌侵染的有效屏障。随果实发育,皮孔大小、数目和裂口均有规律地增加。我们的研究结果进一步证实了苹果轮纹病的潜伏侵染特性。     

Ultrastructure of epicuticular wax aggregates during fruit development in apple (Malus domestica Borkh.)

Summary

Development of wax platelets on the surface of ‘Delicious’ (Malus domestica Borkh.) apple fruit was investigated throughout the growing season using field emission scanning electron microscopy. At 5,000 and greater, wax crystalline structures appeared to be composed of microtubules (MT), aggregates of individual MT to form single platelets, and of one or more platelets. The thickness of a single wax platelet ranged from 116–128 nm, approximately the diameter of a single MT; whereas multiple-platelet aggregates ranged in thickness from 307–428 nm. Individual platelets, multiple platelet aggregates and MT were visible throughout fruit development, as well as on different apple cultivars. Examination of the cuticle from young fruitlets (receptacle diameter = 3 mm) of ‘Chinese Crabapple’ (M. hupehensis Rehd.), which develops without trichomes, best demonstrated early platelet formation. A model for wax platelet and cuticle development on apple is proposed based on these data.     

巴厘菠萝果实发育期间香气成分的变化

采用顶空固相微萃取技术,研究巴厘菠萝果实发育过程中香气成分的组成及变化。结果表明,巴厘菠萝果实发育过程中共检测出48种成分,主要为酯类、烯烃,其中辛酸甲酯、己酸乙酯、辛酸乙酯等成分是菠萝果实的重要香气成分,是菠萝成熟果实的特征香气。巴厘菠萝在果实发育不同阶段,各香气成分的相对含量变化较大。     

液体授粉对苹果坐果率及果实的影响

苹果液体授粉试验结果表明:液体授粉的花朵坐果率较自然授粉提高61.41%,花序坐果率提高13.73%;偏斜果率较自然授粉降低19.6%,果实纵径较自然授粉增加6.43 mm,果实横径较自然授粉增加8.27 mm。     

苹果果锈的发生及防治

<正>果面光洁度是衡量苹果品质的重要因素之一。在苹果果实生长过程中,果实表面出现黄褐色的斑块,称之为果锈。果实出现果锈后,外观变差,品质变劣,商品性降低,轻则销售价格下滑,重则失去商品价值,严重影响生产效益。2021年在甘肃省白银市平川区呈严重发生态势,该区宝积乡吊沟村和大湾村133.33 hm²苹果生产基地,果锈发生率高达35%以上,     

秋季嫁接苹果花芽的技术

秋梢停长后至落叶前30天内应用切腹接法嫁接苹果的中、长果枝，成活率95％以上，且与未嫁接移植的花芽同期开花坐果。进行花芽嫁接移植可在高接换种的当年结果，使小年树增加产量，使幼旺树早结果，也可用来改造直立枝、徒长枝和补充授粉树的花量不足。     

桃果实缝合线软化过程中内源激素的变化

为了明确桃果实缝合线过早软化的原因,以大久保桃为试材,利用气质联用和高效液相色谱的方法,对缝合线软化果(障碍果)和正常果的种仁、缝合线处果肉和其它部位果肉中的生长素(IAA)、玉米素(Z)、脱落酸(ABA)、茉莉酸(JA)的浓度进行了测定分析。结果表明,果肉ABA浓度是种仁的8～9倍,并随着果实的发育逐渐增加,接近成熟时达到最高,主要表现出对果肉成熟的调控作用。障碍果中Z的浓度在内果皮硬化初期明显高于正常果,与其缝合线异常生长(凸起)吻合;障碍果种仁的IAA浓度在内果皮硬化初期明显低于正常果,果肉中IAA浓度在内果皮硬化后上升,且障碍果高于正常果,说明IAA对中果皮细胞的扩大与成熟软化起调控作用。JA在种仁中的浓度是果肉的3～6倍,在硬核初期障碍果明显低于正常果,到硬核结束时则高于正常果,推测可能JA与内果皮发育有关。