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Water relations composition among Egyptian cotton genotypes under water deficit
5-15Views:154Background: 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.
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Study of animal welfare status and heat stress measures applied in dairy cow herds in Hungary
79-82Views:91The following material focuses on dairy production and climate related issues in Hungary. All the data was gathered during PhD
project: Study of animal welfare status in dairy cow herds in Hungary. Relations between animal welfare and climate changes expressed by
increase in temperature are described. Extremely hot weather creates hard conditions for milking cows when animal welfare is highly
compromised. From the preliminary results obtained one might formulate hypothesis that there are still areas on the farms where immediate
actions should be taken to give a relief to cows in hot seasons. There was found significant number of farms with too many animals per one
water trough, dirty water troughs, limited access to water troughs and hazardous surface for cows in critical places where many animals are
gathered. Calves with not sufficient amount of water in hot days and other parts of the year were reported. Silage exposure to the sun and
mouldy food in a silage clump was also found to be an important factor in monitoring impact of warm weather. Half of the farms letting
animals to spend time on the pasture or paddock did not provide shade for animals. Low conception rate of first insemination was predicted
to be influenced by heat stress, what is proved by lack of heat decreasing measures taken on the farms. -
Heavy Metals in Agricultural Soils
85-89Views:69The soil constitutes the basis of the food chain. To keep soil conditions in a good trim is very important, it’s part of the sustainable development and of producing food supply harmless to health.
In some cases, soil productivity is the only important part, qualitative requirements or economical characteristics can improve it. The soil is threatened by two danger factors: the soil degradation and the soil pollution. The accumulation of different harmful and/or toxic substances in the soil is well known. Heavy metals constitute a part of it. Metals in the soil and in the soil-solution are balanced. This balance depends on the type of the metal, on the pH, on the cation-band capacity of the soil, on the redox relations and the concentration of cations in the soil.
To be able to handle the metal contamination of the soil, it is important to estimate the form, the possible extension and the concentration of metals.
Of course, the different types of soils have different physical-chemical, biological and buffer capacity, they can moderate or reinforce the harmful effects of heavy metals. To draw general conclusion of the dispersion and quantitative relations on the metals originated from different contamination sources is hard, because in some emissive sources contamination is limited in small areas but on a high level, some others usually expand on larger areas, and as a result of equal dispersion, the contamination’s level is lower.
Heavy metals – unlike alkali ions – strongly bond to organic materials, or infiltrate in a kelát form. Their outstanding characteristic is the tendency to create metal-complex forms. Kelats take part in the uptaking and transportation of heavy metals. Heavy metals exert their effects mostly as enzyme-activators.
The metals cannot degrade in an organic way, they accumulate in living organisms, and they can form toxic compounds through biochemical reactions.
Lot of the heavy metals accumulate on the boundaries of the abiotic systems (air/soil, water/sediment), when physical or chemical parameters change, and this influences their remobilization.
Human activity plays a great part in heavy metal mobilization, results in the human origin of most biochemical process of metals.
To understand the toxic influence of accumulated metals of high concentration, their transportation from soils to plants or their damage in human health, must clearly defined and investigated.
For effective protection against soil pollution, the types and levels of harmful pollution to soil must identified, regarding legal, technical and soil-science aspects, preferable in a single way. Difficulties in this area mean that toxicity depends on loading, uptake, soil characteristics and living organisms (species, age, condition etc.), furthermore, local and economic conditions considerably differ. -
Ecological Conditions of Agricultural Land Use in Transcarpathia
190-194Views:64The unbalanced anthropogenic effects for several decades resulted in significant technogen damages in the ecosystem of Ukraine. Excessive land development, including the use of slopes, effected the disintegration of the natural balance of lands – arable-lands, meadows, forests, and watershed areas – producing quite a negative effect on the landscape’s nature itself. It has to be stressed that according to other indexes, too, agricultural lands show a tendentious deterioration.
Erosion, caused by water and wind, is one of the most influential factors in the degradation of agricultural soils and in the reduction of the productiveness of benefital lands. Nowadays the degree erosion became significant and it directly endangers the existence of the soil which is a principal chain-link of the agricultural cultivation as well as an irreplaceable element of the biosphere.
The social and political changes in Ukraine’s life demand fundamental modernization in the land utilization both in ecological and in economical aspects. However, these aims can be realized only if, during the developments, we base on the up-to-date results of agronomics, and we do further research in the relations of agricultural land use and environmental protection. According to the latest theories, rational and environmental-safe agricultural production relates to the optimum correlation of the natural- and agricultural- ecosystems as well as to the reconstruction of agricultural areas built on the basis of environmental protection.