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1.
Two apple cultivars, Cox’s Orange Pippin and Worcester Pearmain, were sprayed at high volume for scab control in two seasons with either captan or thiram, with dinocap to control mildew. On Worcester, it was confirmed that thiram reduced crop and increased fruit russet and bitter pit incidence; the proportion of misshapen fruits was also increased. On Cox, thiram reduced crop number, without any compensatory increase in weight, and provided inferior scab control as well as increasing fruit russet.

The application of commercial calcium nitrate (C.C.N.) four times between mid-June and mid-August led to a considerable reduction in the incidence of bitter pit and storage rots in fruits from trees sprayed with captan and dinocap; it also partially offset the greater incidence of bitter pit associated with thiram treatments. In contrast to this, the application of a similar total amount of calcium, either in the form of a standard lime sulphur programme or by adding C.C.N, to the organic fungicide programmes for scab control, i.e. from April to mid-July, failed to reduce the incidence of bitter pit on either cultivar. Neither C.C.N, programme affected cropping, fruit russeting or scab control on either cultivar.

The ratio of potassium to calcium was higher in leaves and fruits from Worcester trees receiving thiram than in those from trees receiving captan; the application of C.C.N, in the summer reduced this ratio in fruits from trees receiving captan but not in those from trees receiving thiram, although it reduced the incidence of bitter pit associated with both fungicide programmes.

Results on Cox show that fungicide deposition and control of scab were independent of fungicide formulation and of the presence or absence of C.C.N. ; mildew control was not affected when C.C.N, was applied as the recommended summer programme.  相似文献   

2.
国光苹果在碱性土壤中易发生缺钙,引起果实苦痘病的发生。本文通过两年的研究证实,果实苦痘病的发生是由于果实内钙素含量低,氮素含量高,氮、钙比值过大的原因。果实中钙素的积累主要是在盛花后的8周前,而果实发育中后期,钙素积累缓慢。树体喷洒钙盐以硝酸钙,氯化钙混同硼砂效果较好。预防苦痘病的发生,还应注意限制土壤氮肥的施用量。  相似文献   

3.
In several commercial orchards the percentages of Ca and K in the leaves and fruit of the cultivar Cox’s Orange Pippin were determined at intervals during one or more years. The values for a series of untreated trees were continually compared with those of a comparable series of trees which were sprayed at about seven-day intervals with a Ca(NO3)2 solution. At the end of each experiment the fruit was placed in storage and later examined for the incidence of bitter pit.

The Ca contents of leaves and fruit and the quotient (K+Mg)/Ca in the leaves of untreated trees showed only a moderate relationship with the percentage of bitter pit. The K content of the fruit was more closely correlated, however.

The level above which much bitter pit was unlikely to occur was found to be approximately 7.5–8 mg Ca in a fruit of 140 g fresh weight.

The total amount of Ca in the untreated fruit increased in a rather regular and comparable fashion in the various experiments. The rate of increase was somewhat higher during the first period of development, until the fruit reached about 20–40 g in weight, than during its subsequent growth.

Spray treatments increased the Ca content of the leaves by 0.2–0.5% of the dry weight; a maximum of 4 mg Ca was added to the fruit, an increase of 47% on the basis of the amount already present. In general the Ca level increased progressively during the season with successive spray applications, and 9–15 sprays reduced bitter pit incidence to about 5%.

The permeability of the fruit tissue to ions diminished as a result of the sprays, and it is suggested that an increase in cell membrane permeability may be involved in the development of the disease.

For commercial orchards, more frequent sprays may need to be applied than are recommended at present to provide effective control of bitter pit.  相似文献   

4.
苹果苦痘病与果实内矿质养分平衡状况的相关性分析   总被引：2，自引：0，他引：2  
对大连瓦房店地区苹果苦痘病病害程度不同的红富士苹果果实进行了氮、磷、钾、钙、镁、铁、锰、铜、锌、硼、钼含量的测定。结果表明:苦痘病的病害程度与苹果果实内的含氮量呈极显著正相关关系,即苦痘病越严重,果实内的含氮量越高;苦痘病的病害程度与苹果果实内的氮/钙比呈极显著正相关关系,即果实内氮含量越高,钙含量越低,苦痘病越严重;病害程度与苹果果实内的钙/(钾+镁)比呈极显著负相关关系;病害程度与果实内的铜含量呈极显著正相关关系;病害程度与果实内的磷、钾含量无显著的相关关系。试验得出:苹果果实内氮含量过高,是导致苦痘病发生的重要因素。  相似文献   

5.
In a pot experiment with apple trees, cultivar ‘Cox's Orange’, Ca was omitted in the nutrient solution for periods of different length. Trees lacking Ca in the latest 23 of the growth period contained 42 mg kg?1 Ca in the fruits, which is 21% below control. In the bulked sample, average size of fruits was not considerably affected, but the distribution of small and large fruits changed toward more smaller fruits. Concommitantly, bitter pit was reduced compared to the control.Sufficient K supply (1.20–1.70% K in leaf dry matter) given to trees receiving high Ca supply depressed Ca concentration in the fruits to 41 mg kg?1, which is 23% below control. Average fruit size was not significantly changed, but the distribution was towards larger fruits. Under these circumstances bitter pit was increased. Ca deficiency, caused either by omission of Ca or competition between K and Ca, increased fruit rot, russeting and cracks on the fruits. Short term variations in Ca levels were not seen to produce any measurable response.  相似文献   

6.
Pruning in late summer was compared with winter pruning on mature 23-year-old spur pruned trees of Cox’s Orange Pippin on M.2 rootstock. Two nitrogen treatments were superimposed, namely a standard dressing of 126 units N (sulphate of ammonia) applied in March as compared with 288 units N (nitrate of soda) applied in mid-August at the time of summer pruning. Summer pruning reduced trunk girth increment, advanced blossom development, increased the amount of red colour on the fruits and drastically reduced the incidence of bitter pit in stored fruit. The treatments did not affect cropping. Nitrogen treatments had no overall effect upon the incidence of bitter pit, but in the first season, when bitter pit was most prevalent, high levels of N applied in August reduced the amount, a similar trend being recorded the following year.  相似文献   

7.
Merton Worcester apple trees in pot culture were supplied for four consecutive years with N, P, Ca and K at two rates. Apples of this cultivar differed from those of cvs Cleopatra and Jonathan both in their response to nutrient supply variations and in the interrelationships among the levels of mineral elements in the fruit and bitter pit incidence at harvest. The association between fruit levels of N, P, K and Mg previously observed in the other two cultivars was absent in Merton. In two years a positive association appeared in Merton between K level and bitter pit incidence. Doubling the K supply reduced fruit Ca level and increased protein N level and bitter pit incidence. A threefold increase in the Ca supply had the opposite effect on each of these variables. Bitter pit incidence was not affected by doubling the P supply, but was increased by supplying extra N, some of which was in the form of ammonium ion. The differences found between Merton Worcester and the two cultivars studied previously under the same cultural conditions demonstrate that any conclusions in this area concerning apples in general are valid only if they are based on findings over a number of seasons in a wide range of cultivars.  相似文献   

8.
Summary

An experiment was carried out over a six year period to relate the storage quality of ‘Cox’s Orange Pippin’ apples to the mineral composition of leaves, fruitlets and fruits and to the climatic conditions during development. The apples were sampled from 24 orchards over a wide geographic area. The extent to which physiological disorders, bitter pit and low temperature breakdown (LTB), and quality attributes, greenness and firmness, of stored fruit could be predicted either before or at harvest was determined. For each response variable, a short-list of up to 12 potential explanatory variables was selected from an initial set of up to 54 possible explanatory variables, using stepwise regression techniques. Predictive models were generated by selecting variables from the initial short-list using a cross validation technique. The average incidence of bitter pit in controlled atmosphere (CA) storage at 1.2% O2 (<1% CO2) was 4% compared with 12% for similar samples stored in air. Predictive models accounted for up to 67% of the variance in bitter pit in air-stored fruit but the percentage was lower (39%) for fruit stored in CA. The concentrations of calcium and potassium in fruit were particularly important for predicting bitter pit in air-stored fruit but less so for fruit stored in CA where more explanatory variables were required for prediction. Fifty one per cent of the variance of LTB in fruit stored in CA was accounted for by a nine-variable model incorporating three climatic variables. A simple three-variable model (leaf nitrogen concentration, harvest firmness and fruit dry weight) accounted for 67% of the variance in ex-store firmness and the addition of other nutritional and climatic variables increased the percentage variance accounted for to 76%. Seventy-one per cent of the variance in the greenness of fruit after CA storage was accounted for by a six-variable model. The possible physiological significance of the explanatory variables in each model is discussed.  相似文献   

9.
A low pH of the soil prevents the specific apple replant disorder (SARD). Not much is known about the effect of a low pH on the growth of fruit trees. Most authors accept a pH of between 5.5 and 6.5 as optimum for apples but this assumption is not based on experimental research. It is feasible that apple trees grow well at a lower pH than has hitherto been accepted. The influence of a low pH on bitter pit needs careful examination.  相似文献   

10.
In all major apple producing countries, applications of foliar calcium (Ca) products to increase fruit Ca content and reduce the incidence of bitter pit in apples are used. Calcium nitrate (Ca(NO3)2), Calcimax and Ca acetate were applied, commencing at three different developmental stages (early, mid and late) of fruit growth. Late Ca(NO3)2 (80 days after full bloom (dafb)) applications increased the Ca content of fruit at harvest more than early (six dafb) and mid (40 dafb) applications. There was a trend towards an increase in bitter pit from early to late applications of Ca(NO3)2 and Calcimax, confirming previous results obtained when applying only Ca(NO3)2. In spite of the very low incidences of bitter pit during these seasons (less than 7%), significant differences between treatments were found between Ca(NO3)2 Mid and other treatments in 2004/2005, as well as Ca(NO3)2 and Calcimax Early and other treatments in 2005/2006. Ca acetate applications did not show any trends in fruit Ca content or bitter pit incidence when applied during the three stages. Thus, products may differ in efficiency of Ca absorption and effectiveness in decreasing bitter pit in fruit when applied during different developmental stages.  相似文献   

11.
Summary

Bitter pit fruit in commercial consignments of apples still poses an economic threat to exporters from South Africa. Mineral analysis of fruit has been used with variable success to predict bitter pit prior to harvest. The possibility of increasing the accuracy of existing predictive models by using analysis of individual fruit rather than pooled samples was investigated. By improving the normality of the distributions of the different minerals and decreasing the overlap between pitted and non-pitted fruit classes, we attempted to improve the reliability of predictions based on variable threshold values. Even though our model produced a correct classification of 85% for non-pitted fruit which can be useful, this was still below the required tolerance expected on the market which, at present, is less than 2% bitter pit in an overseas consignment. The classification for pitted fruit, 63%, was not satisfactory.  相似文献   

12.
土壤有机质对"红富士"苹果产量和品质的影响   总被引：2，自引：1，他引：1  
测定了"红富士"苹果园0~40 cm土层的有机质含量,分析了相应果园苹果的产量和果实品质,为果园科学施肥提供依据。结果表明:土壤有机质含量在2%以上的果园苹果产量高、果实品质好,几乎不发生苦痘病;土壤有机质含量在2%以下的果园苹果产量低、果实品质差,苦痘病发生严重。  相似文献   

13.
Fruit-thinning treatments were applied in the three seasons 1963–65 to Cox trees to investigate the relationships between leaf : fruit ratio, fruit size, cell volume and cell number, and the incidence of rotting and disorders following air storage at 2·8° C. (37° F.) and o° C. (32° F.). Progressively more severe thinning was required, sis fruit development proceeded, to obtain a similar increase in fruit size. This declining response to thinning was accompanied by a progressively smaller increase in the cell numbers of fruits as the treatments were delayed. Thinning also caused an increase in cell-enlargement rate but the magnitude of the response varied between different experiments and did not appear to be related to the developmental stage at which the treatment was applied.

The larger fruits from thinned trees were more susceptible to bitter pit, breakdown, and rotting caused by Gloeosporium perennans, but were less susceptible to low-temperature injury than fruits from unthinned trees. Bitter-pit incidence was related to fruit size within each treatment and was more severe in fruit where the ratio between the potassium and calcium concentrations was high. Low-temperature injury was associated with fruit with low dry matter and potassium contents. Susceptibility to this disorder and to rotting was also influenced by fruit maturity as measured by the progress of the climacteric rise in respiration rate. There were no marked relationships between storage disorders and the numbers or size of cells in fruits produced by the various treatments included in these experiments.  相似文献   

14.
钙素营养与套袋苹果苦痘病的关系   总被引：9，自引：0，他引：9  
为了探讨苹果套袋后苦痘病加重的原因,以富士苹果为试材,对果实发育过程中钙、氮含量的变化规律,果实幼果期和成熟期钙总量,套袋后果实微环境湿度变化及不同有机质果园苦痘病发生率进行了测定。结果表明,未套袋苹果果实在幼果期吸收钙量占成熟果实总钙量30%左右,后期占70%左右,套袋影响了果实对钙的吸收;套袋使袋内湿度增加,果实表面蒸腾作用降低,使果实对钙的吸收受到影响;同时套袋果氮含量一直高于未套袋果,N/Ca增大,促成了苦痘病的发生。增加果园有机质含量,可以改善根际钙离子供应,降低苦痘病的发生。  相似文献   

15.
秋锦苹果苦痘病与果实矿质元素含量和品质相关性的研究   总被引：2，自引：0，他引：2  
以套袋秋锦苹果为试材,测定了苦痘病果与健果不同部位矿质含量及可溶性固形物的含量。结果表明:矿质元素含量果皮果肉,苦痘病果实的Ca含量低于健果,果皮中尤为明显;苦痘病果N、P、K、B含量及N/Ca、K/Ca、B/Ca、P/Ca均高于健果,N/K、N/P和K/P差异不明显;果皮不着色面Ca含量均低于着色面,而N含量均高于着色面。苦痘病果可溶性固形物含量显著高于健果。果皮各矿质元素之间以及各矿质元素与SSC间存在较密切的相关性。  相似文献   

16.
苹果苦痘病又称苦陷病,是苹果成熟期、贮藏期因缺钙而引发的一种常见生理病害,已成为世界范围内影响苹果经济性状的首要病害之一。作者对苹果苦痘病的症状和发生原因进行综述,并总结其防治方法,以期为生产中苹果苦痘病防治提供参考。  相似文献   

17.
对大连瓦房店地区10 a树龄红富士苹果树进行不同的钙、镁肥的施肥处理,在喷与不喷硫酸镁溶液的基础上分别进行硝酸钙土施和喷施以及氨基酸钙喷施,探讨苹果叶片和果实营养元素含量及苹果"苦痘病"病果率状况。结果表明:钙的不同施肥方式和不同钙镁组合处理对苹果树各器官营养元素以及病果率影响差异很大。单独施钙和钙镁配合施用均不同程度提高了叶片中N、P、K、Ca、Mg的含量,而单施镁会降低营养枝叶片中Ca含量。Ca、Mg单施和配施均显著提高了果实中的P含量;Ca对苹果果实N吸收累积具有抑制作用;而Mg则有促进作用。与CK比较,单施Mg处理使得病果率提高了9.5%;单施Ca处理较Ca、Mg配施防病效果更明显。各施钙处理均显著降低了苹果"苦痘病"发病率;不施Ca、Mg处理病果率为4.2%,喷施氨基酸钙、硝酸钙和土施硝酸钙处理病果率分别为0.9%、1.4%、1.2%,病果率依次降低了79%、67%、71%;在施钙的基础上加施硫酸镁后病果率分别为1.9%、2.4%、2.2%,病果率依次降低55%4、3%、48%。钙肥处理以氨基酸钙肥喷施效果最好,而镁肥会加重苹果"苦痘病"的发病率。  相似文献   

18.
Summary

Turkey has a huge wild Pistacia germplasm that mainly includes P. terebinthus, P. atlantica and P. eurycarpa species. In this study, seed and seedling behaviour of these species are characterized at intra- and inter-specific level. Seed and seedlings of 63 Pistacia genotypes: 10 P. terebinthus, 45 P. atlantica and eight P. eurycarpa genotypes from different parts of Turkey were evaluated as their characteristics of germination, seedling growth and budding success. Correlations between morphological traits of maternal trees and seed/seedling characteristics of their progeny were performed as well. There was a large variability for each of the evaluated character at the inter- and intra-specific level. However, in the average, P. eurycarpa had the highest germination percentage, whereas P. terebinthus had the lowest. The seedling growth of P. atlantica was better than P. terebinthus and P. eurycarpa. Budding success was not significant between species. Correlation coefficient values suggested that a few of the associations between morphological traits of maternal trees and seed germination and seedling characters of their progeny vary between those of three species.  相似文献   

19.
Summary

‘Reinette du Canada’ apple (Malus domestica Borkh.), which has been declared a Protected Designation of Origin (PDO) product throughout the European Community, is severely affected by bitter pit during storage, but increasing demand for organic produce requires chemical post-harvest treatments to be replaced with organic practices. The objective of this work was to determine the optimum stage of fruit maturity to improve the storability of high quality ‘Reinette du Canada’ apple during storage without applying post-harvest treatments. Seasonal conditions influenced fruit quality and the occurrence of storage disorders in ‘Reinette du Canada’. Harvest maturity also influenced the quality of ‘Reinette du Canada’ apple during storage, with later harvests reducing the development of bitter pit and increasing the soluble solids content:titratable acidity (SSC:TA) ratio. This study suggests that the SSC:TA ratio was a useful parameter for determining the optimum harvest maturity for high acidity, ‘Reinette du Canada’ apple. High quality fruit were obtained after long-term storage when the SSC:TA ratio exceeded 11.0, and fruit firmness at harvest exceeded 90 N. If these thresholds were not achieved, the quality of harvested ‘Reinette du Canada’ apples may not be sufficient to market fruit with the PDO designation. The results of our study also suggested that skin hue angle (hº) measurements may provide a quick and useful index that could replace fruit firmness measurements in the future.  相似文献   

20.
Severe hand thinning of fruitlets on Cox’s Orange Pippin trees five weeks after full blossom led to a doubling of fruit weight by harvest. Although the rate of cell division was stimulated slightly, the larger fruit size was due mainly to an increased rate of cell enlargement.

The respiration rate of whole fruits was slightly higher after thinning and the onset of the climacteric rise was advanced. Respiration per cell was correspondingly higher in the larger cells of the thinned fruit and respiration per unit protein was similar to that of fruit from unthinned trees.

Potassium, magnesium, and phosphorus contents, expressed on a fresh weight basis, were higher in the cortical tissue of the thinned fruits. Calcium per unit fresh weight was unaffected by thinning and the ratio of calcium to cell surface remained relatively constant throughout development in both types of fruit.

Senescent breakdown and bitter pit developed during storage only in the thinned fruit. Slight differences in the incidence of rotting and low temperature breakdown between the two types of fruit are attributed to the effects of maturity rather than of fruit size.  相似文献   

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