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Foliar Nutrition and Post-Harvest of Onion Seed: Effects of storage temperatures, storage period and foliar nutrition
29-47.Views:202The 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.
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Pollen viability of ‘Besztercei plum' clones depending on the effect of the year
115-121.Views:149The percentage of dark staining pollen grains was higher in spring of 1996 than in the previous year. Data in 1998 resemble those of 1995, concerning the large amount of medium staining pollen grains in the majority of clones. Some clones produced excellent quality pollen also in the third year. whereas there were significant differences in other clones in various years.
The warmer February-March period in 1995 induced an early blooming, and frost affected the orchard not only in winter months, but also immediately before and during blooming. Thus, frost was the possible cause of weaker quality pollen this year. In 1996 warming began a bit late, but it was not broken by drastic falls in temperature, except for the middle of April, when a smaller frost affected the orchard. It is likely that this frost did not influence pollen quality of `Besztercei' and 'Early Besztercei' plum clones significantly. In 1998 warming was continuous and steady, the orchard was not affected by frost immediately before blooming. In March, however, there was frost almost every day, according to daily minimum temperatures.
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Comparison of frost damages in apple plantations cultivated with environmental friendly growing technology
21-24.Views:169The global changes in climate and meteorological conditions have many negative consequences, which may diminished with adequate measures. In our continental climate, the winter frosts but also the late spring frosts are always threatening. There are technologies to avoid late frost damages (with spray irrigation or with smoking), but against winter minima, we are nearly helpless. The different damages experienced recently called our attention on the question of optimal condition, which is a delicate balance between the vegetative activity and the provision of nutrients. The excesses on both ends are increasing the danger of damages (Zatykó, 1980). Our examination was performed in the plantation, which was cultivated according to ecological and integrated technologies. The variable condition of the trees gave opportunity to evaluate the effects of cold temperatures as frost damages. Our results will represent not only the differences between varieties but also the effects of the growing technologies – which influence the condition of the plants – consequently, the measure of frost damages.
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Sweetcorn production from transplants
45-48.Views:156In our trial we tried to find out how the time of propagation and transplanting influenced the growing season of sweet corn along with some major properties relevant to quality. The following technological variations were compared with the help of the variety Spirit (normal sweet, very early ripening): transplanted plants with floating row cover (with 2 planting dates); transplanted plants with no row cover: direct seeded plants with no row cover. The 21 day transplant growing period reduced the growing period by 16 to 20 days, compared to the technology used in the existing practice of production. Earliness had a negative influence on ear size, nonetheless it is worth while to attempt since the market is not so exacting with new products in the early period. Covering the seedlings in the early season was clearly beneficial, as the floating row cover provided protection for plants against lower night temperatures which are common in this period.
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Contributions to the resumption of growth in ecodormant buds of apple
35-40.Views:119The resumption of development in ecodormant buds in terms of establishing a functional vascular connection between the inflorescence primordia and spur tissues in apple trees was investigated. Differentiation of the xylem elements could be observed first in the pedicel of the flower primordium, in the middle of January. Much later (at the beginning of April) there were mature xylem vessels in the wall of the receptacle and, merely a procambial strand for the ovule primordium which was at this time an undifferentiated protrusion of meristematic cells, only. As for phenological development of buds incubated at a temperature of 20 °C, it was the slowest in buds sampled in January, faster in buds sampled in the middle of February and, buds from the middle of March responded very quickly. The function of temperatures needed both for xylem differentiation and for the flower primordium to achieve maturity is pointed out. The nature of frost damage in vessel elements, as well the relationship between chilling requirement and growth features of apple cultivars will be discussed.
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In vitro investigation of King Oyster Mushroom [Pleurotus eryngii (DC.: Fr.) Quel.] strains in vegetative growing phases
47-53.Views:193The king oyster mushroom ( Pleurotus eryngii) is more and more popular amongst the producers due to its excellent taste and relatively easy cultivation . In the course of our work we collected 15 king oyster mushroom strains from various habitats in Hungary in order to get a better picture about the growth of the vegetative mycelia of the species and its different strains. In the in vitro experiments we investigated the growth of the strains at various temperatures and pH. incubated them in light and darkness and in aerobic and anaerobic atmosphere. In addition to these we measured the weight of dry mycelia produced in a given time by the strains. Our results showed that the above mentioned environmental conditions resulted in a very different growth rate of the vegetative mycelia of the various P. eryngii strains. These results may provide valuable data about the vegetative phase of the cultivation.
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Impact of planting dates on yield and pod quality traits of snap bean under short-temperate season climates
57-63.Views:140Snap bean, a warm-season crop, have low frost tolerance. The optimal temperature for seed emergence and plant growth is important. Therefore, appropriate planting dates for adapted varieties has paramount significance in improving pod yield and quality of snap bean under short cool season climates. Three snap bean cultivars planted at 3 different dates were examined to evaluate the effects of planting dates on snap bean pod yield and quality traits in a 2-year study in a short season climate in Manitoba, Canada. Results of this study showed that three, two weeks apart, planting dates had a non- significant effect on marketing yield of three different cultivars tested in this study. Planting dates showed significant effect on un-marketable yield, pod fresh weight, pod length and total soluble solids. Higher marketable and un-marketable yields along with longer pod length and soluble solids, in all three cultivars, were more profound when seeded at mid and late planting dates. Snap bean grew under higher temperature and accumulated more growing degree days (GDD) when planted in mid June and early July when compared to early June planting. These results conclude that marketable yields of snap bean were not significantly affected by planting dates when seeded-two weeks apart-in shorter growing environments which allow commercial and market gardeners, in northern areas with shorter growing seasons to optimise planting snap bean, without reducing pod yield and quality.
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Relationship beetwen the phenological features of pear cultivars and the main meteorological parameters in a gene bank with 555 pear
59-63.Views:172The trees observed are grown at Ujfehert6, Eastern Hungary in a gene bank with 555 pear cultivars. Each of the cultivars was monitored for its dates of: the beginning of bloom, main bloom and the end of bloom and ripe phenophasis separately between I 984 and 2002. We analyzed the statistical features, frequency, distribution of these phenophasis and its' correlation the meteorological variables bet ween the interval. During this period the meteorological database recorded the following variables: daily mean temperature (°C), daily maximum temperature (0C), daily mini m um temperature (0C), daily precipitation (mm), daily hours of bright sunshine, daily means or the differences between the day-time and night-time temperatures (0C). For the analysis of data the cultivars have been grouped according to dates of maturity, blooming period as well as types of the seasons. Groups of maturity dates: summer ripe, autumnal ripening, winter ripe cultivars. Groups of blooming dates: early blooming, intermediate blooming, late blooming cultivars. At all the separated groups we analyzed the relationship between phenophasis and meteorological variables. During the 18 years of observation , the early blooming cultivars started blooming on 10-21 April, those of intermediate bloom date started flowering bet ween 20 April and 3 May, whereas the late blooming group started on 2- 10 May. Among the meteorological variables of the former autumn and winter periods, the winter maxima were the most active factor influencing the start dates of bloom in the subsequent spring. For the research of fruit growing-weather relationships we used simple, well known statistical methods, correlation and regression analysis. We used the SPSS 1 1.0 software for the linear regression fitting and for calculation of dispersions as well. The 1ables made by Excel programme.
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Relations of phenometrical indices of apple fruits with weather variation in the assortment of varieties of an apple gene bank
115-120.Views:195The purpose of phenometry is to examine the measurable parameters of the plants in order to follow up the consequences of weather processes. We should fi nd the reasons, why the diameter of fruits grows larger in one season and smaller in the next. Variation may occur as a response to insuffi cient provision of water or nutrients, but also because of pathological effects and of extremely high or low temperatures, moreover, of extraordinary heavy fruit load. There are phenometrical characteristics, which consider the fi nal consequences (density of fl owers, fruits set, drop of fruits), whereas other parameters could be followed up (size, length and width of fruits) as the dynamic components of growth. The quantitative parameters of growth are functionally related to each other, where the weather conditions, soil humidity and nutrients are on the input side, thus it is possible to model the growth of fruits as a function of the environment. Initially, the relations between the main weather variables and the phenometrical data have to be cleared. In the present study, the interactions between the mentioned phenomena are presented and numerically defi ned.
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Study on the time of emergence of the first generation of raspberry cane midge (Resseliella theobaldi BARNES)
43-45.Views:172The raspberry cane midge (Resseliella rheohaldi BARNES) is a major pest of raspberry in Europe. The accurate prediction of adult midge emergence is an important part of integrated raspberry protection. Calculation of the accumulated effective temperature may be used in prediction. The values of the critical accumulated effective temperature needed for the first flight of the midge differ in the European regions. In our experiments we investigated the first generation of the midge in Hungary. Our results show that the critical accumulated effective temperature for the first flight was the lowest compared with results received in other European countries. The emergence of males of the first generation was found at 145-194 day °C, and females started laying eggs a few days later.
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Flower density and winter damage of apricot and peach varieties
53-56.Views:224Hungary is located on the northern boundary of economical apricot and peach production. The present assortment of varieties and the actual, not adequately selected growing sites cause a permanent risk of winter and spring frosts in their cultivation. The field observations are performed at Debrecen, the Experiment Station Pallag, on 20 apricot and 21 peach varieties. The flower density among the varieties attained 3-4-fold differences. Three categories have been suggested for both species. The density was inferior in Hungary established varieties compared with the new varieties of foreign origin. The minimum temperatures of January 9, 2009 was –17,6 °C , and of December 21, 2009 also –17,6 °C. In some varieties the damage of buds attained 100%. For estimating the yield security, we need to consider also the flower density and the frost damage together. For a mediocre yield, we need a flower density in both species of at least 0.2 living bud/cm. The results confirm the statement that in Hungary, the revision of growing sites is indispensable in order to develop a profitable and competitive apricot and peach growing industry.
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Determination of the cold tolerance off sour cherry cultivars with frost treatments in climatic chamber
49-54.Views:203Nowadays, sour cherry buds can be seriously damaged by spring and winter frosts. Unlike other fruit species threatened by high frost damage, sour cherry cultivars have not been assessed for frost tolerance. The aim of .our survey was to establish the relative cold tolerance of the Hungarian cultivars after treatment in a climatic chamber, and to optimize the methodology formerly elaborated for the frost treatment of apricot. Fourteen cultivars of Hungarian sour cherry (Prunus cerasus) were used in the experiments, which spanned the winters of 2005/2006 and 2006/2007. Our data were used to rank cultivars in two groups according to their levels of cold resistance. We also recommend critical temperatures and treatment times for the testing of sour cherry cultivar resistance to cold in climatic chambers.
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Damages caused by winter frosts, their temporal variation and frequencies in the main fruit growing region of Transdanubia and of the East Tisza regions of Hungary
89-97.Views:200The aim of the study was the study of winter frost damages, especially their changes expressed in temporal frequencies on the main fruit growing regions of the country. In our earlier paper, we introduced the calculation with the term LT50 as the quantitative expression of temperature threshold, when the lethality halves the survival of plant organs, buds or cells causing 50% death rate. The damage is highly dependent on the temperature and on its duration (length of time), but not at least on the frost tolerance of the fruit trees. The incidence and severity of damage is analysed according to the apricot and peach varieties of their different susceptibility or tolerance too. Four fruit growing regions, two of the in Transdanubia and two belonging to the regions east of the Tisza river have been selected to trace the incidence and severity of frost damages. For that purpose, we analysed the history of the past 60 year period, 1951–2010, utilising the database of the network of 16 meteorological stations of the countrywide service. Being aware of the values of LT50 during the rest period and afterward, the compulsory dormancy caused by low temperature, the number of days, the probability of frost damage could be predicted. The role of the orographical profi le, the height above sea level and the exposition of plantations are also decisive. Within the same plantation, 20–30 m difference of level may cause large diversity in temperature and frost damage. Air circulation and regular incidence of winds within the Carpathian basin modify the occurrence and severity of damages. Lowlands near the southern and northern country borders are particularly exposed to winter frosts. Most damages are reported in February, as temperatures below –20 °C especially if the fi rst part of the winter was mild, or in January was a warm period. With the end of the physiological rest period of the trees, the frost-susceptibility increases signifi cantly, and a cold period of –15 °C may cause heavy damage. This study proves that tolerance of varieties infl uence the damages substantially. By planting frost tolerant varieties, winter frost damages could be diminished by 40–50% at the same growing sites. Present results may also offer a tool to estimate the risk of frost damages and express the security of yields at a given site based on the data accumulated in the database over many years.
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Erratic fruit set in almond under warm climates
59-64.Views:256The cause for the erratic yields of the two main almond cultivars grown in Morocco has been searched in order to recommend possible solutions for a high and stable production. The lack of sufficient bloom overlap between ‘Marcona’ and ‘Fournat de Brézenaud’ in many years may be one of the reasons of this erratic behavior, but not the only one, as the same behaviour may be observed in two simultaneously blooming cultivars, ‘Ferragnès’ and ‘Ferraduel’. The relatively high temperatures observed during the blooming period
significantly reduced the stigma receptivity of these cultivars and, as a consequence, their effective pollination period, showing that stigmatic receptivity is a limiting factor for fruit set in ‘Marcona’ and ‘Ferragnès’ and their subsequent yield reduction under warm conditions. Thus, in the present context of global warming, the search for cultivars tolerant to heat stress during flowering will acquire a special interest, as well as the combination of cultivars with the same chilling and heat requirements to ensure a simultaneous bloom. -
Biochemical changes in pear (Pyrus communis L. depending on different phases of the dormancy
47-50.Views:145Pear cultivars of variable frost tolerance were tested as for frost injuries suffered as a consequence of artificial freezing temperatures during the endodormancy as well as the ecodormancy. Damages were registered according to a visually defined scale, then peroxidase and polyphenol-oxidase activity was checked in buds, spurs and limbs. According to our results, 'Packham's Triumph' was the most frost tolerant cultivar. Regarding enzyme activity of both enzymes, the performance of cultivars displaying different susceptibility was also different in spurs as well as in buds. Results referring to the endodormancy were especially instructive. During the ecodormancy, data obtained at the same time indicated the differences existing between the developmental stages of dormancy in the respective cultivars.