Foliar Nutrition and Post-Harvest of Onion Seed: Effects of storage temperatures, storage period and foliar nutrition

The aim of onion bulb storage is to meet consumer demand for extended availability of onions whilst maintaining product quality. The principal biological factors leading to onion bulb deterioration are respiration, resumption of growth and pathogen attack. In onion bulbs a dormant period, when sprouting and rooting cannot be induced, is followed by a period of internal changes that prepare the bulb for breaking of dormancy and subsequent growth. Out of storage, the bulb then proceeds towards flowering and seed production. Two successive winter seasons of 2008/2009 and 2009/2010 were conducted under sandy soil conditions to study the effect of spraying with 12 commercial compounds on yield and yield components of onion seeds and storage The seed yield of each commercial compounds plot from previous experiment was divided into two groups, storage under room temperature and 5°C. Seeds transferred immediately after drying to Increasing Export Competition of Some Vegetable Crops Project Laboratory located in Faculty of Agriculture, Cairo University. The effects of storage temperature, storage period and foliar with some commercial compounds on onion seed quality were considered. Storage in 5°C had the higher germination percentage than storage in room temperature. Results indicated that as storage period increased the germination percent decreased. The treatment with boron or amica in the first season had the highest germination percentage. While, the treatment with union Zn, union feer, union Mn, boron, elga 600, caboron, amica, hummer or amino X had the highest germination percentage in the second season. Storage in 5°C resulted in higher moisture content than storage in room temperature. Regarding the effect of storage period on moisture content, the water content was significantly increased with prolongation of storage period. The lowest values of water content were recorded for treatments with union feer, shams K or boron in the first season, and union feer, shams K, boron, magnesium, shetocare or hummer in the second one. Catalase activity was significantly decreased as storage period increased. The treatment with shams K, boron, shetocare or amino X had the highest catalase activity in both seasons. Peroxidase activity was significantly decreased as storage period increased. Foliar application with boron had the highest peroxidase activity in both seasons. Seed stored in room temperature had the higher malondialdehyde content than those stored in 5°C in the second season. The malondialdehyde content increased as storage period increased. The treatment with magnesium, caboron and the control in the first season, and the treatment with magnesium and the control in the second season had the highest malondialdehyde content.

The quality and storage efficiency of some apple varieties as a function of picking date, area of production and duration of storage

Numerous apple varieties have been tested parallel with traditional Jonathan varieties during four years, 1990-1994 on three different geographical areas of Hungary. The picking time took place at three different times in a year: ten days before the probably optimal picking time, at close-to-optimal picking time, and ten days after the optimal picking time. The effect of storage on quality of fruits have been tested in February, March, and April under circumstances of a semi-industrial storage experiment.

The results of experience can contribute to answer numerous current, from point of view of practice important topics:

  • The stochastic relations between various fruit quality parameters at different varieties
  • The change of fruit — quality during storage
  • The effect of different picking date on storage losses
  • The possibilities of storage — loss predicting by the utilization of multiple regression analysis.

The most important results of experiences are as follows :

  1. The starch — degradation test and Streiff — index are well applicable for practical purposes to determine the optimal harvest-date.
  2. On base of analysis of various losses and physiological diseases the high importance of mass loss is obvious. In the variety Jonnee the earlier picking date considerably increased the mass loss. The effect of variety on mass loss is rather limited. In the Jonathan varieties the Jonathan spot was a rather important physiological disease. The late picking time increased the frequency of Jonathan - spot. At optimal date of harvest at Jonnee the frequency of Jonathan -spot was lower, than at Jonathan M 41. In the Jonathan M41 and Jonnee the importance of scald was rather limited, but in the Wellspur Delicious and Smoothee this disease occurred relatively frequently. In the Smoothee the earlier picking time considerably increased the probability of scald.
  3. The multiple regression analysis yielded reliable results, fit for prediction of storage losses and diseases on the base of chemical and physical properties, determined at the time of picking.


Storage ability and differences of carrot varieties defined by firmness changes measured with new non-destructive acoustic method

Carrot production in Hungary is getting more important these days. The condition of the quality insurance is to choose the proper variety of carrot and store on optimal conditions therefore measuring firmness and matter parameters are very important. Four varieties of carrots were measured (Bangor, Olympus, Napa and I3olero). The roots were stored in unsealed polyethylene bags at 4-10 degrees Celsius and 95% relative humidity. The vegetables were measured three times: at harvest, after I .5 months of storage and after four months of storage. The samples were tested by non-destructive acoustic. Stillness measuring method during the 112 days experiment for firmness. In laboratory were measured weight loss, dry material -NO3 and sugar content as an important matter parameters.

The firmness change as a function of storage time are the following: First part of the storage (after 60 days), the Napa variety changed least in the case of acoustical parameter, at the same time its weight Foss and dry material content were not rise significantly, while its sugar content increased with 50%. The l3olero variety had the highest changes of sugar content during storage. During the second storage period, the softening speed of all samples was increased. The Bolero had the highest average mass loss (32,7%) and NO3 content changes as well. All measurements showed the largest changes for the Bolero variety. The highest percentage of dry material content was found by the Bolero and Napa varieties (18-20%).

In this experiment, we found that the Bolero variety showed the greatest loss in compressibility during storage. If both firmness and weight loss results are considered, the Napa variety is found to be the most storable variety in sort period. The Bangor variety was found to be the best for long-term storage.

Effects of Foliar Nutrition on Onion Seed Storage under Modified Atmosphere Packages

Modified atmosphere packaging (MAP) and controlled atmosphere storage techniques to reduce the oxygen around the food are largely used for the preservation of fresh produce. There have been great technological advances in this area of preservation, particularly as it refers to improving the quality and shelf-stability of highly perishable food products, such as produce. Two successive winter seasons of 2008/2009 and 2009/2010 were conducted under sandy soil conditions to study the effect of spraying with 12 commercial compounds on onion seeds storage under modified atmosphere packages. Germination percent of seeds decreased in 5°C than storage in room temperature. Germination percent of seeds was gradually decreased with increasing the storage period. Packaging treatments had a significant effect on germination percent of seeds. All the packaging treatments had the higher germination percent than the paper package (control). The highest germination percent after 12 months of storage was recorded for the treatment with non perforated polypropylene in room temperature and polyethylene and non perforated polypropylene in 5°C. Catalase activity decreased with the prolongation of storage period. The non perforated polypropylene package had the highest catalase activity. The treatment with non perforated polypropylene had the highest catalase activity after 12 months of storage in both room and 5°C temperatures. Peroxidase activity of seeds was gradually decreased with increasing the storage period. The highest peroxidase activity after 12 months of storage was recorded in non perforated polypropylene in both storage temperatures.

Effects of Foliar Nutrition on Onion Seed Storage under Controlled Atmosphere

Storage of fresh fruits and vegetables prolongs their usefulness. The principal goal of storage is to preserve the commodity in its most useable form for the consumer. The extension of storage life and the improvement of quality of fresh fruits and vegetables can be supplied by harvesting at proper maturity, control of post-harvest diseases, chemical treatments, refrigeration, controlled and modified atmospheres. Two successive winter seasons of 2008/2009 and 2009/2010 were conducted under sandy soil conditions to study the effect of spraying with 12 commercial compounds on onion seeds and storage under controlled atmosphere. The germination percentages were 85.50, 86.85, 83.75 and 82.15 for CA1, CA2, CA3 and CA4, respectively. Water content of onion seeds was significantly increased with decreasing storage temperature in all controlled atmospheres. Water content values were 4.48, 4.40, 4.55 and 4.54 for CA1, CA2, CA3 and CA4, respectively. There were significant decreases in water content with increasing exposure periods. The lowest water content was recordednfor the exposure periods of 120 and 240 days. Catalase and peroxidase activities were decreased with the decreasing of storage temperature, whereas malondialdehyde content was increased. The exposure for 120 days recorded the highest catalase activity. The highest value of peroxidase (11.72) was recorded for CA2. Peroxidase activity increased as exposure period increased until 120 days and then decreased. Cold storage temperature (5°C) showed the highest malondialdehyde content followed by room temperature. The CA2 showed the lowest malondialdehyde content compared with other controlled atmospheres. The exposure period of 120 days had the lowest malondialdehyde content.

Interaction of nutrient supply and crop load of apple trees (Malus domestica Borkh.)

Long term fertilisation trials were combined with storage experiments with 'Jonathan' apple trees and fruits to study influence of tree nutrition on quantity and quality of crop. The site of experiments is a typical Carpathian-basin environment with loamy silt soil, high lime content and arid summers. Conclusions has been drown from six years' set of data. Augmented levels of soil fertilisation increased cropping capacity of apple trees, however, the fruit load has not met with cropping capacity in every year. More the def cit came into view in crop load, less the fruit quality resulted in. The deficit in cropping capacity, however, could not have been determined with simple rates as fruit weight per trunk circumference or similar. Better determination was obtained where foliar nutrient contents were correlated to crop per tree figures. In general terms, the N and Ca content in leaves increased with yields when K and P content formulated reciprocally. When storage quality of 'Jonathan' apple fruits were related to crop load (kg/tree), influence of crop deficit became visible. As the crop load and foliar nutrient levels interacted, the fruit quality (number of disordered apples after 6 month of storage) subjected of both physiological phenomena. Higher determination degree were obtained when crop load was assessed together with single or multiple foliar analysis data.

Work organization and economic analysis of the postharvest of an unique Hungarian product

We have viewed a business in the south of the Great Plain Region from an economic point of view in 2004-2005. The main activity there is pear growing and storage. Four varieties of different time of ripening and storing are grown there. We have measured all the relevant activities, worked out a local normative and prepared a detailed technology. The economic evaluation was based on this data. Activities, like disinfection, pre-storage disinfection and selection, in-storing and out-storing, classification after storage, packaging, as well as loading trucks, were monitored by variety. Storage loss was determined and widely varied according to varieties, length of storage and time of out-storing. Different varieties resulted in different quality classes after storage. Price depended on the quality classes. Economic evaluation was carried out when all the relevant costs and revenues were known. Fixed and variable costs of storage were determined, break-even point was calculate and the market position of the product was evaluated.

Changes in the Dry Matter and Sugar Content of Nantes Type Carrots during Storage

Changes in the dry matter and sugar content occurring during the winter storage of Nantes type carrot hybrids grown on soils of different quality were studied in 199912000 and 200012001. The dry matter content of the varieties tested depended on the production site and on the weather conditions prevailing in the growing season. The increase in the dry matter content during winter storage reached 6 to 7 per cent in the crop grown in a dry year and 1.5 to 2 per cent in a rainy year. The sugar content was lower in the rainy year (1999) and on brown sand (Szatymaz) than in the rather dry year (2000) and on chernozem soil with residual forest (Tordas), respectively. The increase in sugar content (1 to 5 per cent) measured at the end of storage was related to the season's weather conditions.

Storability of paprika varieties measured by non-destructive acoustic method

During our experiments, the storability of paprika (Capsicum annuum) samples was measured by a non-destructive acoustic method. The aims of our work were the determination of the applicability and reproducibility of the acoustic stiffness method for paprika, the investigation of the optimum measuring conditions. In order to compare the main paprika varieties regarding shelf-life, our further aim was to follow the softening phenomenon or textural changes (i.e. changes in stiffness) of different paprika varieties measured by the non­destructive acoustic stiffness method. Five different varieties of paprika grown in hydroponics growing system were used for the measurements. All paprika varieties were stored at 20 °C for two weeks. Samples were tested on every 2nd or 3rd day. The acoustic method was found to be suitable to follow the softening of paprika samples. The characteristic frequency of the acoustic signal could be well detected and clearly separated from the other vibration peaks. Tapping the top of the paprika was observed to give a clearer and less noisy signal compared to the signal obtained by tapping the sample's shoulder. The acoustic results showed the same tendencies with regard to softening during storage as the impact method showed in our previous experiments.

Dried fruit quality judging on different sweet cherry varieties grown in Hungary

The modern consumer's habit needs new material to enrich biological complete human foods. The mueslis contain more and more part of dried fruit. The organic nutrition prefers fruit, grown in that area, where they will be consumed. Therefore we thought on cherries, because earlier, almost all kind of fruit, including cherries, were dried. First of all we collect all sweet cherry varieties grown in Hungary (by the National List), (Harsányi &. Mády, 2005) than they were dried similar way to the dried plum. After a short storage the samples were judged, by different consumers. The aim was to know, which variety gives the best result, i.e. which variety is the most suitable to gather round for dried fruit. At the judging we used the methods, worked out by the National Institute for Agricultural Quality Control in Hungary. Our work shows orders, which varieties were the best, from different point of view. (e.g. colour, size; firmness of flesh, flavour, and total score). The best varieties by total score will be shown and characterised shortly (Apostol, 1996; Beschreihende Sortenliste Steinobst 1997; Brózik & Kállay, 2000; Tóth, 1997; Harsányi & Mády, 2005; Horváth, 2004; Tomcsányi, 1979).

The effect of storage to optical properties in case of two apple fruit varieties

The keeping quality of fruits is a very important factor in storage point of view, since it could be elongated the consumption time of fruits. In many cases the storage may be necessary, e.g. in short time it is not able to market due to the rich harvest, or all fruits could sell in markets throughout the year. The keeping quality of various fruit species is greatly different; moreover it could be observed some differences between the varieties as well. In our research, we have investigated the spectral properties of the external surface and fl esh of two ripe apple varieties – Jonagored and Granny Smith – before and after storage (about 3°C and about three weeks). The hyperspectral investigation was carried out with AvaSpec-2048 Fiber Optic Spectrometer. The experimental results represented the differences between healthy and chilling injured apple fruits. Furthermore, some indices were created to given countenance to the spectral differences.

Changes in the Carotene Content of Nantes Type Carrots during Storage

Changes in carotene content occurring during winter storage in Nantes type carrot hybrids grown on soils of different quality (sand and loam) have been investigated. The carotene content of the samples grown in a rainy year (1999) was lower than that of the samples grown in a dry year (2000). Lower carotene content was found in carrots produced on sandy soil (Szatymaz) than on loam soil (Tordas). The increase in carotene content (2-11 mg1100 g) measured at the end of winter storage was related to the season's character.

Examination of fruit juices produced with aseptic technology

The quality of finished products with a 100% fruit content is influenced to the greatest extent by the fruit-base (fruit pulp and fruit juice concentrate) used. In terms of the production of the fruit juice, the minimization of the quantity of the dissolved oxygen, which can cause detrimental oxidation processes to start, is a very important aspect. Scientific experiments specify de-aeration before pasteurization as the solution to the problem. The choice of the packaging material and the manner of packaging also contribute to the preservation of the alimentation-biological and pleasure value of fruit juice. On the basis of the results of the experiments, regarding the parameters which are important in terms of quality, i.e. dissolved oxygen content, C-vitamin concentration, deepening in the colour and sensory features, Tetra Bric Aseptic packaging proved to be better in the examined cases. Storage circumstances also influence the quality of fruit juice.

Response of sour cherry cultivar `Érdi jubileum' fruits to modified atmosphere packaging after ethephon spraying

Sour cherries are not adapted to long storage. The largest percentage of sour cherries reaches the consumer either directly or indirectly through the tin can or the frozen pack. Different concentrations of ethephon usually are used commercially to facilitate harvesting sour cherry fruits that this hormone influences on fruit quality. The objective of this study was effect of ethephon preharvest application on sour cherry fruits quality during storage period at modified atmosphere packaging was investigated. Modified atmosphere packaging used with 10, 15 and 75 percent for 02, CO, and N2 respectively that those held at 0 °C. This gas compounds synchronous to 0 °C temperature caused to increase shelf life postharvest of fruits. Fruit samples were evaluated at harvest date and after 6 weeks in storage. Skin fruit colour, pH, total soluble solids, titrateable acidity, sugar/acid ratio, firmness were monitored. Ethephon concentration influenced on total soluble solid, titrateable acidity, sugar/acid ratio and L* value. In more case, 225 ppm ethephon's concentration has no observable different to control samples. Thus, the best ethephon's concentration was 225 ppm ethephon's concentration.

Texture changes of vegetable cultivars measured by non-destructive methods

According to our experiments the tested group of non-destructive methods offers a useful tool not only to follow the texture changes of vegetables during storage but to characterize the firmness and vision parameters during the growing period as well. Advantages of these methods are: they are mobile, easy to set up, easy to use and quick. The suitable maturity state — and so the optimum harvest date also - can be determined by these methods. In addition, these methods can be built into sorting lines making possible to sort and classify great amounts of produces. These methods help the producer to offer homogenous products of controlled quality. They can be used for measuring different effects on vegetable's quality parameters (fertilization by different microelements, different irrigation effects on the product) as well.

Review on rain induced fruit cracking of sweet cherries (Prunus avium L.), its causes and the possibilities of prevention

The rain induced fruit cracking is a big, serious and costly problem for cherry growers. Cracked fruits lose their value and they are not marketable because of the poor fruit quality. Cracked fruits have different storage diseases and shorter storage and shelf life.

There are many influencing factors of the cherry fruit cracking such as: water uptake; fruit characteristics (fruit size, fruit firmness; anatomy and strength of the fruit skin, stomata in fruit skin, cuticular properties, osmotic concentration, water capacity of the fruit pulp, growth stage of the fruit,); orchard temperature and other environmental conditions;

The most effective protection technique is the plastic rain cover over the tree rows. The installation of these equipments is too expensive for the cherry growers. That is the reason why researchers tried to find other less expensive and sufficiently effective ways against the Lim induced fruit cracking.

Several calcium formulas: calcium chloride (CaC1,), calcium hydroxide (Ca (OH)2) and calcium nitrate (Ca(NO3)2 ) can be sprayed in appropriate concentration. Spraying with other mineral salts (aluminium and copper salts, borax) and PBRs (Plant Bioregulators) may be also effective to reduce fruit cracking.

Experimental approach in apple tree nutrition

Authors present synthesis of experimental work, performed in the last decades, for better understanding nutritional behaviour of apple trees and related problems in fruit quality. There were evidences supporting possible deteriorating role of potassium in feeble physiological status of apples, if applied in excess. More intensive studies proved that higher potassium uptake into leaves and fruits might be also the result of increased sink power of individual fruits. Nevertheless early senescence of apples during storage and also sensibility to bitter pit were successfully related to the increased sink power of fruits, casual relations in excessive NPK fertilization, although increase in sink power need further investigations. Impaired weather conditions during early development of fruits, hostile orchard practices in pruning, thinning, irrigation and also unskilled application of growth regulators may also contribute in the enhancement of sink power and in weakened physiological status of apple fruits.

Structural differences arise between fruit cuticles of two apple cultivars during long term cold storage

Apple fruits are covered by hydrophobic cuticle that provides protection against desiccation, pathogens, excessive water absorption and radiation. The features of cuticle affect the quality and storability of the fruits. It was aimed to evaluate the correlation between peel ultrastructure and weight loss in fruits covered by waxy bloom (cv. Florina) and without bloom (cv. Red Rome van Well) during 4-month cold storage. SEM (scanning electron microscopy) was used for visualization of the fruit surface and fruit weight was also measured. Several studies have revealed that there may be correlation between the ultrastructure of cuticle and its water permeability. Our results confirmed this phenomenon in case of two cultivars. The weight loss per fruit surface area unit of ‘Florina’ was found significantly higher than that of ‘Red Rome van Well’. At the same time the cuticular surface of the fruits contained more micro-cracks in case of the former cultivar. These data confirmed the relationship between the density of cuticular micro-cracks and the water vapour permeability. We concluded that this feature is more significant than the amount of natural waxy bloom on fruit surface.

Post-storage sensory quality of apple varieties

The changing situation of apple production in Hungary has given rise to a great demand for new varieties. Besides bearing capacity, fruit quality and suitability for new training systems, consumer preference is one of the grower's main considerations. Growers need reliable information in order to choose the appropriate variety, so consumer tests have become essential. Altogether, 1 I traditional and new varieties were involved in this project. In the first part of the experiment, panelists ranked the coded samples according to their appearance. In the second part, apples were cut into unpeeled slices and the samples were also coded. The assessors were asked to taste them and rank them again. The sensory tests were held after three different storage periods.

Storability of some apricot varieties as affected by storage period

The aim of this study was the estimation of storability of 10 apricot varieties in regard to percentage fruit weight loss, firmness, acidity and T.S.S in fruit during storage periods from one week to 4 weeks. All the variety gave the same trend as all of them loss weight, firmness decreased, acidity and T.S.S decreased but the differences were not the same in all varieties. in case of some varieties the percentage of fruit weight loss reached to about 9 % after 28 days also the differences between varieties in two seasons refer that this character is determined by genetic factors beside effect of environmental and agriculture factors.

Changes in Some Quality Criteria During Controlled Atmosphere (CA) Storage of Peaches

Intensive research has been implemented on different aspects of the bee pollination of pear in Hungary in the past decade, extending to the following topics: the effect of the opening sequence of the flowers within the inflorescence of pear cultivars on the effectiveness of bee pollination; the nectar production of flowers of pear cultivars; intensity of honeybee visitation and their foraging behaviour at the flowers of pear cultivars; flower constancy of honeybees to pear plantations; competition by weeds in bloom for bee pollination in flowering pear orchards; and some aspects to the bee pollination strategies of pear plantations (the effect of the limitation of bee pollination period on the set and the yield, possible compensation of frost damage of flowers by bee pollination in pear orchards, the optimal size of single cultivar block in pear plantations). The results of these studies are reviewed in this paper and some important aspects that need further studies are outlined.


Effect of modified atmosphere package on apricot fruit storability

The aim of this work was to study the effect of modified atmosphere package (MAP) on apricot storability. Apricots (Prunus armeniaca L.) cultivar Jumbo cot were harvested at commercial ripening stage. The fruits were treated with different storage treatments as following: i) control storage for 13 days at 1 °C, ii) stored fruit at 1 °C for 10 days then 3 days at shelf at 25 °C, iii) fruit stored in MAP at 1 °C for 13 days and iv) fruit stored in MAP at 1 °C for 10 days then 3 days at shelf at 25 °C. Data showed the positive effect of MAP in keeping the apricot fruit for long time with better quality than the control fruit. MAP showed positive effect by recording the lowest fruit weight loss, the highest firmness and lowest chilling injury and fruit decay.

Effect of different flower thinning techniques on annual fluctuation of macro and micronutrients in sweet cherries

The seasonal dynamic of macro- and micronutrients uptake of a sweet cherry cultivar cv. 'Katalin' (Prunus avium L.) was studied according to apply different flower thinning techniques. Beside control treatment, three thinning treatments were performed: (I) thinning for I flower/inflorescence, (2) thinning for 2 flower/inflorescence, (3) thinning for 3 flower/inflorescence. Soil examination was carried out to establish the growing conditions of orchard site. Moreover, for studying the temporal dynamic of nutrient uptake plant analytical examination was performed four times per year based on leaf collecting according to the phenological phases. It was found that the macro- and micronutrients contents of leaves were showed significant differences between treatments before ripening, at ripening and after ripening stage. It was found that thinning has influence on mineral composition of leaf. Flower removal unbalanced the equilibrium of generative and vegetative processes. The applied manual flower thinning treatment resulted improving vegetative processes like nutrient uptake and storage.