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  • Water relations composition among Egyptian cotton genotypes under water deficit
    5-15
    Views:
    154

    Background: water shortage is one of the major factor effects on growth characters and yield of most crops. Objective: this study was conducted to get to know the reactions of some Egyptian cotton genotypes to water deficit. Methods: The genetic materials used in this study included thirteen cotton genotypes belonging to Gossypium barbadense L., from the Cotton Research Institute (CRI), which was devoted to establishing the experimental materials for this investigation. Results: the ratio of GCA/SCA was less than unity for all studied indices, indicating predominance of non-additive gene action (dominance and epistasis), which is an important in exploitation of heterosis through hybrid breeding. Results: The data showed significant reduction in water relationship characters for all parental genotypes under stress conditions. The Egyptian variety Giza 68 gave high values for most water relationship characters. Data revealed that the greater the value of tolerance index is, the larger the yield reduction is under water deficit conditions and the higher the stress sensitivity is becoming. The parental genotypes Giza 96 showed the highest reduction in yield under water deficit conditions. At the same time, the cross combination Minufy x Australy showed higher values of yield reduction followed by the combinations Giza 67 x Australy. Of the male parents, the Russian genotype 10229 recorded the best GCA values for most water relationship characters. At the same time, the female parents, the old Egyptian genotype Giza 67 recorded the best values and exhibited good general combined for most water relationship characters. The cross combinations Giza 86 x Pima S6, Giza 77 x Pima S6, Giza 94 x Dandra and Giza 96 x Australy showed significant desirable SCA effect for most characters. Conclusion: relative water content %, osmotic pressure, chlorophyll and carotenoids content indicates better availability of water in the cell, which increases the photosynthetic rate. Also, the higher level of proline accumulation in the leaves which was recorded under deficit water suggests that the production of proline is probably a common response of plant under water deficit conditions.

  • The impact of cultivar and irrigation on yield, leaf surface temperature and SPAD readings of chili pepper
    103-108
    Views:
    183

    Paprika is an extremely popular and widespread plant species in Hungary. Chili peppers belongs to paprika and it can be consumed fresh or processed. The production of peppers began with the cultivation and control of some parameters for good results of paprika production. The aim of this article is to compare the water supply of four chili pepper hybrids ("Habanero", "Hetényi Parázs", "Unikal" and "Unijol") by means of investigation on open field and to examine how different temperatures and water stress factors influence the yield of chili peppers. The experiment area consisted of four different hybrids in three different irrigation treatments (control, deficit- and regular irrigation). The chlorophyll content was estimated with SPAD and the leaf surface temperature with Raytek MX4 TD. Our research concluded that deficit irrigation produced the highest yields for all cultivars and the lowest yields for the highest water supply.

  • Effect of arginine, putrescine and spermidine on the polyamine, proline and chlorophyll content of tobacco (Nicotiana tabacum L.)
    39-43
    Views:
    117

    Polyamines, such as spermidine (Spd) spermine (Spm) and their direct precursor, the diamine putrescine (Put) are vital and essential aliphatic amines which are also present in plants. Although ethylene and polyamines are also involved in fruit ripening, the genes coding them must also take part in other biosynthetic pathways. In the ethylene and polyamines play an important role in development of salt stress tolerance, and in responses for biotic and abiotic stresses. Exogenous application of all three main polyamines (Put, Spd, Spm) increase salt tolerance of plants, but, accordingly to previous experiments, spermidine has the main effect on the enhancement of salt tolerance. Nicotiana tabacum L. plants were grown in vitro on MS medium, the treatments were as follows: arginine (150 mg l-1), putrescine (10 mg l-1), spermidine (10
    mg l-1). Proline, chlorophyll a, b and polyamine contents were measured. The obtained results show that the arginine decarboxylase and the spermidine synthase genes involved in polyamine metabolism, cannot be enhanced by exogenous addition of their precursor molecules. On the contrary, the spermine synthase gene has a positive effect to the lower-class forms of polyamines.

  • Physiological examination on cadmium sensitvity of some maize and sunflower varieties
    169-173
    Views:
    95

    Cadmium is one of the most dangerous heavy metals, which may cause serious problems in certain physiological processes of living organisms even in small amounts. In our work we analysed how cadmium affects some physiological parameters of different maize and sunflower hybrids. The chlorophyll contents and the morphological changes of the root were examined. We received different results in terms of the cadmium tolerance of these two plants.

  • Integrated nutrient supply and varietal difference influence grain yield and yield related physio-morphological traits of durum wheat (Triticum turgidum L.) varieties under drought condition
    111-121
    Views:
    107

    The ever-growing world population entails an improvement in durum wheat grain yield to ensure an adequate food supply, which often gets impaired by several biotic and abiotic factors. Integrated nutrient management, such as nitrogen rate × foliar zinc × sulphur fertilization combined with durum wheat varieties were investigated in order to examine the dynamics of yield and yield related physio-morphological traits under drought conditions. The four durum wheat varieties, three-level of nutrient supply (i.e. control, sulphur, and zinc), and two nitrogen regimes (i.e. zero and 60 kg ha−1) were arranged in split-split plot design with three replications. Zinc and sulphur were applied as foliar fertilisation during the flag leaf stage, both at a rate of 3 and 4 liters ha-1, respectively. Results showed existence of genetic variability for grain yield, plant height, NDVI, SPAD and spike density. Foliar based application of zinc and sulphur at the latter stage improved the plant height. Nitrogen fertilized varieties with lower spike numbers showed to better yield formation. Co-fertilization of nitrogen and zinc improved grain yield of responsive varieties like Duragold by about 21.3%. Spikes per m2 were statistically insignificant for grain yield improvement. It could be inferred that the observed positive effect of sulphur, nitrogen and zinc application on physio-morphology and yield formation substantiates the need to include these essential nutrients in the cultivation system of durum wheat.

  • Relationships between nutrientsupply, genotype and some physiological properties of winter wheat
    141-145
    Views:
    131

    The chlorophyll content (SPAD), leaf area index (LAI) and leaf area duration (LAD) of three winter wheat varieties have been investigated on a chernozem soil. Three winter wheat varieties (GK Öthalom, Pannonikus and Genius) in three different nutrient-supply levels have been involved in our experiment in the crop-year of 2010/2011. The investigated physiological properties have been set against to the yield results. Upon the results of this comparison it has been stated that there is a close relationship between the investigated physiological properties and yield averages. The SPAD-values showed a growing tendency parallel to the growth of the nutrient-supply levels. The varieties have the highest SPAD-values at the nutri ent-level of N120+PK. Compared to the yield averages we have stated that varieties that have higher SPAD-values have realized higher yields as well. Higher nutrient dosages have increased in the leaf area. In case of all the three varieties the highest LAI-values were measured at the flowering stage (23. 05.) in the treatment whit N120+PK. Varieties with higher leaf area have produced higher yields as well. Parallel to the increasing nutrient-supply levels the value of leaf area duration increased as well. We measured the highest LAD-values in the treatment of N120+PK nutrient-level. By the LAD-values it can be stated that more durable and larger leaf area has been produced in the flowering and ripening phenophases, due to the higher nutrient-dosages. Analysing the relationships between the results it can be stated that there is a strong positive relationship between fertilizer treatments and SPAD-, LAI- and LAD-values. The genotype showed a strong positive correlation to SPAD-values. Yield averages showed strong positive correlation to SPAD-, LAI- and LAD-values as well.

  • Study of some physiologic properties of different genotype sweet corn hybrids
    105-110
    Views:
    96

    The effect of nutrient-supply (control, N120+PK) and two different genotypes on the physiologic properties of sweet corn has been investigated in the crop-year of 2011 on chernozem soil in the Hajdúság region. The experiments were carried out at the Experimental Station of the University of Debrecen in Debrecen-Látókép. The experiment was sewn in two different sowing times: the 21st April can be considered as an early, while the 19th May as a late sowing time. The two involved hybrids were Jumbo and Enterprise. The applied plant density was 65 000 plants per hectare.
    Our aim with this experiment was to study the plant production, just as the main affecting factors of its development and dynamics, like nutrient-supply and genotypes. We aimed to study and analyse the relationships between these factors and plant production. In this study following parameters were measured and calculated: photosynthetic activity, chlorophyll-content (SPAD-value), leaf area index (LAI) and leaf area duration (LAD). Regarding the analysis of photosynthetic activity values no obvious relationship between the measured values and the applied hybrids, just as nutrient-supply has been revealed. 
    Analysing the SPAD-values it can be stated that the chlorophyll-content of the measured leaves showed an increasing tendency due to the nutrient-supply. The highest values have been measured in the intensive cob development phase of the early sowing time plots.
    Regarding the LAI-values we have found significant differences between the fertilizer treatments in both sowing time treatments. In case of the leaf area duration values – that is derived from the LAI values – nutrient-supply has positively affected the duration of the assimilation area.