2013). Soleimani (2006) reported marked increase in number of grains spike-1 of wheat for foliar application of boron and zinc, respectively. Soleimani (2006) reported increase in biological yield for foliar application of zinc. Grewal et al. (1997) reported increased wheat production with application of zinc and boron over control. Grain protein content and baking quality highly depend on genetic background and environmental factors, especially influence of drought and heat stress, during the grain filling period. Storage protein is a method to investigate genetic variation and to classify plant varieties (Isemura et al. 2001). During the growing season may have their roots in the upper soil profile where the density is greater than a dry face, but the plant is able to continue its vital work. So in this case the lower part of the soil, root density at low but adequate moisture, they are responsible to provide water for the plants (Li, et al. 2006). In other words, when faced with stress the ability of plant roots to absorb the increase in dry matter allocated to the root system will (Mohamadi et al. 2004; Michele et al. 2009). As a result of changes in morphological parameters, such as root elongation occurs (Aerts et al. 1999) . Many plants by increasing the proportion of assimilates allocated to root growth and thus increasing the ratio of root to shoot and enjoying more water available to the lack of moisture will respond (Michele et al. 2009; Kaffi et al. 2000) . Therefore this study was planned to examine effect of drought stress and Zinc fertilizer on some root traits of chickpea cultivars.
tosynthesis. Drought stress also causes membrane damage, which can be severe enough to lead to plant death . Furthermore, drought stress increases the oxidative stress on plants . All of these affect photosynthesis negatively. Thus, the mean SPAD value of a group can be used to examine its resistance to drought stress: the higher the mean SPAD value is, the more resistant the plant is to drought stress. As Graph 3 shows, the relatively less affected groups shifted from the 2 mM group and the 10 mM group before the simulated drought stress, to the 10 mM group and the 20 mM group after the simulated drought stress. This means that an increase in Calcium concentration may facilitate maize seedlings withstand drought stress. However, the effects of 20 mM Calcium seem to be less than that of 10 mM Calcium, suggesting that contrary to common knowledge, higher than normal Calcium concentrations may have little effect helping maize seedlings resist drought stress.
ABSTRACT: Daily courses of the actual transpiration of a forest stand were determined by an experimentally verified mathematical Soil – Vegetation – Atmosphere Transfer model. The results refer to the Norway spruce (Picea abies [L.] Karst.) monoculture situated in the highest locations of the Beskids Mts. Drought-free transpiration was estimated as a model simulation run for nonlimiting soil moisture exceeding the level of decreased availability of water. Drought-induced reduction in transpiration was quantified as a difference between actual transpiration and simulated transpiration for moist soil. The results led to conclusions that dry soil causes a significant reduction in actual evapotranspiration and its components in comparison with moist soil. Simultaneously, the effect of soil desiccation was compensated by extremely high evaporative demands of the atmosphere, so that the daily totals of evapotranspiration and its components remained sufficiently high. The high values of global radiation and saturation deficit in the air favourably influenced the water regime of the analysed forest stand in the dry period.
Drought stress is one of the most important abiotic stress factors which are generally accompanied by heat stress in dry season (Dash and Mohanty, 2001). Water deficit stress due to drought, salinity or extremes in temperature is the main limiting factors for plant growth and productivity resulting in large economic losses in many regions of the world (Borsani et al, 2001). Plants respond to water stress through a number of biochemical, physiological and developmental changes (Pattanagul, 1999). Drought is perceived as the most significant environmental stress in agriculture worldwide, and improving yield under drought is therefore a major goal of plant breeding (Cattivelli et al., 2008). With a projected increase in drought with climate change, the breeding for drought-tolerant crops is even more emphasised (Witcombe et al., 2008). Water is essential at every stage of plant growth and agricultural productivity is solely dependent upon water and it is essential at every stage of plant growth, from seed germination to plant maturation (Turner, 1991). Drought stress is one of the most important abiotic stress factors which are generally accompanied by heat stress in dry season (Dash and Mohanty, 2001). Water deficit stress due to drought, salinity or extremes in temperature is the main limiting factors for plant growth and productivity resulting in large economic losses in many regions of the world (Borsani et al., 2001). Plants respond to water stress through a
The foliar application of B had a highly significant effect on total plant B content. Plants grown under high ML resulted in highest B uptake and low ML resulted in lowest B uptake. It might be due to the fact that plants grown under low ML might have received lower amount of water from the soil compared to plants grown under medium and high MLs. Because of the water scarcity to transpire, there might be the formation of waxes in the cuticle layer of the transpiring leaves of the plants grown under low ML to minimise the water loss from the transpiration which might prevent the foliar-applied B to enter inside the leaf. The significant effect of the B treatment on total plant B content under different soil moisture levels indicates that the plants were able to take up foliar-applied B.
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growth[25, 26]. These results coincide withthose of, [27, 28, 10] on Vigna sinensisCymbopogon flexuosus and Catharanthus roseus respectively.The shoot fresh and dry weight, root fresh and dry weights are also reduces in drought stress condition. The reason of this the reduction of shoot length, root length and number of number of nodules directly effect on fresh and dry masses of shoot and root and due to the deficiency of water in the plant causes the senescence. The following results are collaborated by the effect of drought on various crops [29, 30, 31]. However, by the application of Pam increases the shoot length, root length, number of nodules, shoot fresh weight, root fresh weight, shoot dry weight and root dry weight under drought stress conditions. When Pam is applied to the soil, it gets adsorbed water 500 times more than its own weight [32, 33, 34] thereby improving the porosity, aeration, thermo and water regime, water holding capacity, fertility and stability of soil, which in turn delays senescence, improve the growth and development of plants [18,19]. The other reason for the improvement in these parameters may be due to the nutrients made readily available by this polymer, which have been reported to increase the activity of cell division, cell expansion and cell elongation . These results are collaborated on soyabeen .
Plants encounter biotic and abiotic stresses that imperil their survival. Plant framework grows and creates to its most extreme potential just under an ideal scope of factors like water, temperature, light and so on. At whatever point there is a shortage among these factors, the result is diminished development and advancement higher plants are in this manner regularly subjected to a few, harsh environmental stresses, which antagonistically influence their development, digestion and yield. Drought, salinity, low and high temperatures, surge, contaminations and radiation are the essential factors constraining the productivity of the yield plants. A few biotic (creepy crawlies, microbes, organisms and viruses) and abiotic (water accessibility, temperature and nutrients) stresses influence the development in higher plants. Among them, drought stress is a noteworthy abiotic factor constraining the development and influencing the productivity of the plants.
Drought stress and drastic condition of the Northern region of Saudi Arabia especial high temperature in summer season affect widely on the chemical component of plant and its biological actively plant grow in these condition adapt to this stress by accumulation different compound, T. orientalis it is tree grow in garden and farms, when it grows in desert habitat show different content, Gc-Ms analysis of the terpenoid fraction of the plant where it is best fraction given high antimicrobial and Larvicidal activity was done and show the presence of many promising diterpene compounds, Ferruginol, Torulosol, dihydro, 18-Oxo-kauran-17-yl acetate and Andrographolide. The antibacterial testing showed that, the tested gram-positive bacteria exhibited good susceptibility to the terpenoid fraction of methanol extract, which was Staphylococcus epidermidis and Staphylococcus aureus, recorded 13.0±0.7 and 11.0±0.0 mm inhibition zones, respectively. Indicating promising antibacterial activity against the gram-positive pathogens. While all the tested gram-negative bacteria recorded weak or no susceptibility. The larvicidal activity of plant was studied on Spodoptera littoralis, The lethal concentration was 27.63 % of terpenoid fraction of Thuja orientalis. The plant can considered as a good herbal insecticide instead of synthetic insect side after further studies where the IC 50 :
It is suggested that several explicit mechanisms, termed ‘biodiversity effects’, underlie diversity–ecosystem functioning relationships and it is likely that these mechanisms also mediate the response to environmental perturbation. These consist of three components: the sampling effect, functional complementarity and positive species interaction or facili- tation. 2, 10 – 12 The sampling effect is the dominance of par- ticular species. This component is suggested based on the theory that a highly diverse ecosystem is likely to contain some superior species, which have strong effects on ecosystem functioning. 12,13 Complementarity arises through niche parti- tioning between species, resulting in the alleviation of inter- specific competition over limiting resources. 1, 2, 11, 14 – 16 Ecosystem stability should be correlated with biodiversity if resources limit the growth of species in a community and if the resource partitioning allows for the increased efficiency in total resource use over temporal and spatial scales. Facilitation (positive interspecific interaction) occurs when a certain species has the ability to mitigate the harsh environ- mental conditions to which a community is exposed or when there is a supply flow of resources from one species to others which is beneficial to the survival of the recipients. Thus, productivity is enhanced with increased diversity if facilitative interactions increase. 1, 17, 18 If the effect of facili- tation was predominant under perturbed conditions, it would lead to an increase in ecosystem stability. 18 Individual instances or combinations of these biodiversity effects have been shown in experimental work under controlled environ- ments. It might be expected that these effects would also be observed in the perturbed environment.
Abstract: This study was conducted to assess rangeland resource utilization and management practices, specifically to assess the effect of drought and conflicts over rangeland resource, expansion of unwanted plants species, in Afdem district located in sitti zone, Somali regional state of Ethiopia. In this study, Pastoralist rangeland resource utilization practices were assessed using structured questionnaire (50 households), visual observation and group discussions, The data obtained through the questionnaire from assessment of rangeland resource utilization and management practice were analyzed by using SPSS version 16 by using description statistics like frequency, percentage then presented in the form of tables. Nearly, majority of the respondents were lack of education (illiterate) and pastoralism was the most dominant production system in the study area. The natural grazing land was more important and only source of livestock feed and there is no privately owned land and also most of the respondents preferred communal ownership of the grazing land for the period of time that is to come. The most common rangeland and livestock management practice strategies adopted by the pastoralists included seasonal migration, herd splitting, range classification and soft grazing as mentioned by the majority of the respondents. So strengthening of the pastoralists’ indigenous knowledge through giving attention and recognition, as well as organizing awareness creation programs on proper rangeland management and improvement measures which suitable to the area must be undertaken. In the district, expansion of rain fed crop production might be full of risks, because of the uncertain of the rainfall as well as the nature of the community.
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Groundnut (Arachis hypogaea L.), is one of the most important oilseed crops grown as a major source of vegetable oil and protein, both for human consumption and as a fodder crop. Because groundnut is usually grown in rain fed condition, it has been hypothesized that improving growth under water limited conditions will serve better cultivation in water scarce areas also. The objectives of the present study were to understand the effect of drought, PBZ, ABA and in combination on the photosynthetic pigments constituents of A. hypogaea under field conditions. MATERIALS AND METHODS
et al., 2002). The propiconazole (PCZ) is a triazole group of systematic fungicide. The triazole compounds, such as pacloputrazole and PCZ, have a growth regulating properties. It induced many morphological and metabolic changes such as reduction in shoot elongation, stimulating of rooting, inhibiting gibberellins biosynthesis, increased chlorophyll content change in carbohydrate status and increased cytokinin synthesis (Fletcher and Hofstra, 1988). The triazole treatments to change the morphological and physiological effects in plants include inhibition of plant growth, elongated chloroplast and increased the photosynthetic pigment contents, thicker leaf tissue, increased root and shoot ratio (Jaleel et al., 2008). Salicylic acid (SA) is a phenolic compound synthesized throughout the plant kingdom via the phenylpropanoid pathway. SA plays an important role in abiotic stress tolerance, and considerable interests have been focused on SA due to its ability to induce a protective effect under stress. SA significantly alleviated growth inhibition induced by drought and manifested by less decreased fresh and dry mass, plant height, root length, chlorophyll and many physiological roles (Kang et al., 2013).
The SPI and SPEI for time scales of 12 - months were applied to all stations so that the severity of the drought can be estimated for a long term effect. As established earlier, a drought event is defined when the SPI value reaches a value of -1.0 or less and the drought occurrence terminates with the SPI reaches a positive value. Initially, descriptive statistics for the five (5) stations were computed. The descriptive statistics which consists of Mean, Standard Error, Median, Mode, Standard Deviation, Sample Variance, Kurtosis, Skewness, Range, Minimum and Maximum values, Sum and Count were computed and a simple regression analysis was carried out to determine the Coefficient of Determination, R 2 between SPI values and time series data from
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Regarding the results of this study can be concluded that the drought stress through the impact on photosynthesis system (maximum quantum efficiency Mtv systm II) reduces the yield components and ultimately yield in a tangible form. Therefore, also it seems that the increased content of chlorophyll meter and keeping it in drought conditions causes to increase the effect severity of stress on the plant and reduce more the leaf area. In fact, the plant by reducing the leaf surface in stress conditions reduced the transpiration level to prevent the wasted water and therefore, despite reducing the total amount of chlorophyll in leaves, the chlorophyll content increases per unit of leaf area . Therefore, to evaluate drought tolerance, traits such as Fv and Fv/Fm are more reliable that even with the yield also has a high correlation. the F v / F m parameter is a well characteristic to
Today, considering the important role of groundwater and due to the severe loss in its level, predicting the changes in the level of groundwater is an important issue in the management of water resources, particularly in arid and semi-arid areas. In the present age, population growth and factors related to it on the one hand, and the occurrence of drought on the other hand have always caused more efforts on the part of human to find appropriate solutions for supplying and water and its optimized consumption. Therefore, in this study it was tried to study the effect of drought on groundwater and pistachio products in Zarand.
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suffering from frequent natural disasters. Among the most expensive natural disasters, drought is a chronic natural disaster that can have severe and long-lasting impacts on water resources, agriculture, ecosystems, and human societies . The impact of drought events is often worst in developing countries because their economies are driven mainly by agricultural products that are adversely affected by meteorological droughts . Drought may generally be defined as a scarcity of water in a region over a prolonged period of time triggered by a lack of rainfall. Presently, great effort needs to be expended on researching future changes in rainfall patterns, which are the major causes of drought in Bangladesh and can lead to adverse changes in economic and social development. The effects of gradual climate changes and extreme weather events may negatively impact overall socio-economic development in many regions, and therefore, the scientific community and policymakers need more information about the probability of future occurrences of such events [7,8].
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Another plant mechanism to suppress consequences of drought conditions is by accumulation of osmoprotective compounds which have an important role in osmoregulation and in the maintenance of the water regime. Proline, like immino acid, due to its polarity is very often referred to as one of the main osmoprotectants. In this study, the concentration of free proline was significantly increased under the non-irrigated conditions both in oaks (increase of 28%) as well as in hornbeams (increase of 30.7%) compared to watered controls. Our findings are consistent with the results reported by Hu et al.  who evidenced that foliar proline levels were enhanced in the drought plus air warming treatment across three oak species (Quercus robur, Quercus petraea and Quercus pubescens). Similarly, the simultaneous measurement of proline and related compounds on the leaves of drought stressed Quercus robur plants showed that fifty-six days of water deficit exposure resulted in increased foliar free proline levels of drought stressed oak compared to well-watered control . Finally, Topić  found that free proline content in the leaves Quercus robur seedlings subjected to drought stress was almost twice higher in comparison to control treatment. Our findings are in accordance with the results that were gained from other tree species as well. For example, studying the influence of three different water regimes (100, 50, and 25% of the field capacity) on two contrasting populations of Populus przewalskii, Lei at al.  found that drought not
The increased use of cement is essential in attaining a higher compressive strength. But, cement is a major source of pollution. The use of nanomaterials by replacement of a proportion of cement can lead to a rise in the compressive strength of the concrete as well as a check to pollution. Since the use of a very small proportion of Nano SiO2 can affect the properties of concrete largely, a proper study of its microstructure is essential in understanding the reactions and the effect of the nanoparticles. The existing papers show the use of admixtures in concrete mix. In the present study, no admixture has been used in order to prevent the effect of any foreign material on the strength of the concrete. This study is an attempt to explain the impact of a nano-silica on the compressive strength of concrete by explaining its microstructure.
indicating Ho was rejected in other words there was a positive direct effect of Environmental-Based Alo Village Potential Management. Thus it is clear that the Management of Environment-Based Alo Village Potential for the community will have an impact on improving the quality of the community and can foster community participation in the development of Alo Village in bone raya sub-district, bone bolango district. The results showed that the Management of Alo-based Village Potential for the community on indicators of natural resource management in the fields of alo waterfalls and LA (lundua lo Alo), for respondents are very high, showing that the public interest in increasing household incomes and improving the welfare of the community is very big to answer the instrument questions in management on indicators of natural resources is very high , but the obstacle is pad a road access, funding and bell um priority alo village program and district government, and not yet become a regional and even national target, because the road access cannot be reached by vehicle facilities, which must be covered by walking for an hour and a half. But in terms of selling value for tourist destinations is very expensive, because it has a river that has clean water quality from a spring with a waterfall from Mount LA. Agriculture in alo village, has very good fertility land , which is distributed in three hamlets, namely; Dusun Tindahiya, Bondula and Tilayo village, thus most of the livelihoods of the people are farming , so that the agricultural products become a lot of capital and become a source of welfare for the people of the village of Alo. The fishery and marine fields of Alo village are surrounded by tombilato beaches and blue sea villages, which produce high nutritional marine fish. This shows that if the management of the Environment-Based Alo Village Potential is managed properly for the community, it will have an impact on improving the quality of the village community in Alo.
It is found from test results that only PPFRC-0.25% and PPFRC-0.5% showed an increase of 7.1% and 8.29% of tensile strength in 28-days strength. And remaining PPFRC specimens had less tensile strength as compared to PCC. The cause of reduction in tensile strength of the mix is may be due to the presence of fibers in mixture which introduce more air voids and this also cause consolidation and compaction problems. The effect of various amounts of PP fibers (Vf) on concrete mixand average strength-time curves for these concrete mixtures is shown in Figure 10- 3.5.