scholarly journals Study of drought tolerance of hybrid material of home plum in southern Russia

2020 ◽  
pp. 94-98
Author(s):  
A. A. Kochubey ◽  
R. Sh. Zaremuk

Relevance. The aim of the research was to determine the physiological characteristics of the manifestation of resistance to stress factors (drought) of new hybrid forms of domestic plum and the allocation of the most drought-resistant in the environmental conditions of southern gardening.Methods. The article presents the results of drought tolerance studies of six promising hybrid forms of home plum (17–1-55, 17–1-69, 17–2-64, 17–2-78, 17–2-81, 17–3-79), concentrated in the genetic collection of SKFNTSVV. The main indicators characterizing the varieties and hybrids of home plum were determined as drought tolerant — the water content of the leaves and the water holding capacity of the leaves under conditions of summer moisture deficiency.Results. The water content of leaf tissue of hybrid forms in the hottest period (second — third decade of July) was heterogeneous. The highest water content in tissues was observed in hybrid seedlings 17–2-64 (63.1%) and 17–2-81 (59.6%). The smallest value was observed in the hybrid 17–3-79 and amounted to 49.7%. According to the data obtained, it was concluded that the studied hybrid forms do not differ in high water content, with the exception of hybrid 17–2-64, in which the water content can be characterized as above average. It was found that the water retention capacity of most hybrid forms is average. The total water content after withering in the studied hybrids was more than 80%. The greatest decrease in the amount of water in the leaves was observed in hybrids 17–1-55 (18.9%), 17–2-64 (18.5%), 17–3-79 (18.4%); the smallest — in hybrids 17–1-69 (13.3%), 17–2-78 (13.6%), which indicates a highwater retention capacity of the last two hybrids. With a general assessment of the hybrid fund of home plum, it was found that most hybrids studied have low hydration of leaf tissue and average water retention capacity. Based on this, two drought-resistant hybrid forms were identified: 17–1-69 and 17–2-78, which, despite the low water content, are distinguished by good water-holding ability in comparison with other hybrids and, as a consequence, the conservation of leaf turgor.

Author(s):  
Anthony S. R. Juo ◽  
Kathrin Franzluebbers

Allophanic soils are dark-colored young soils derived mainly from volcanic ash. These soils typically have a low bulk density (< 0.9 Mg/m3), a high water retention capacity (100% by weight at field capacity), and contain predominantly allophanes, imogolite, halloysite, and amorphous Al silicates in the clay fraction. These soils are found in small, restricted areas with volcanic activity. Worldwide, there are about 120 million ha of allophanic soils, which is about 1% of the Earth's ice-free land surface. In tropical regions, allophanic soils are among the most productive and intensively used agricultural soils. They occur in the Philippines, Indonesia, Papua New Guinea, the Caribbean and South Pacific islands, East Africa, Central America, and the Andean rim of South America. Allophanic soils are primarily Andisols and andic Inceptisols, Entisols, Mollisols, and Alfisols according to the Soil Taxonomy classification. Allophanic soils generally have a dark-colored surface soil, slippery or greasy consistency, a predominantly crumb and granular structure, and a low bulk density ranging from 0.3 to 0.8 Mg/m3. Although allophanic soils are apparently well-drained, they still have a very high water content many days after rain. When the soil is pressed between fingers, it gives a plastic, greasy, but non-sticky sensation of a silty or loamy texture. When dry, the soil loses its greasiness and becomes friable and powdery. The low bulk density of allophanic soils is closely related to the high soil porosity. For example, moderately weathered allophanic soils typically have a total porosity of 78%, with macro-, meso-, and micropores occupying 13%, 33%, and 32%, respectively. Water retained in the mesopores is readily available for plant uptake. Water retained in the micropores is held strongly by soil particles and is not readily available for plant use. The macropores provide soil aeration and facilitate water infiltration. The high water retention capacity is also associated with the high soil porosity. In allophanic soils formed under a humid climate, especially those containing large amounts of allophane, the moisture content at field capacity can be as high as 300%, calculated on a weight basis. Such extremely high values of water content seem misleading.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Lu Zhang ◽  
Jichang Han

Abstract The Mu Us sandy land in China’s Shaanxi Province faces a critical water shortage, with its aeolian sandy soil endangering the regional eco-environment. Here we investigated the effects of feldspathic sandstone on water retention in an aeolian sandy soil from the Mu Us sandy land. Feldspathic sandstone and aeolian sandy soil samples were mixed at different mass ratios of 0:1 (control), 1:5 (T1), 1:2 (T2), and 1:1 (T3). Soil-water characteristic curves were determined over low- to medium-suction (1–1000 kPa) and high-suction (1000–140 000 kPa) ranges, by centrifuge and water vapor equilibrium methods, respectively. Results showed that the addition of feldspathic sandstone modified the loose structure of the aeolian sandy soil mainly consisting of sand grains. The van Genuchten model described well the soil-water characteristic curves of all four experimental soils (R2-values > 0.97). Soil water content by treatment was ranked as T2 > T3 > T1 > control at the same low matric suction (1–5 kPa), but this shifted to T2 > T1 > T3 > control at the same medium- to high-suction (5–140 000 kPa). T2 soil had the largest saturated water content, with a relatively high water supply capacity. This soil (T2) also had the largest field capacity, total available water content, and permanent wilting coefficient, which were respectively 17.82%, 11.64%, and 23.11% higher than those of the control (P-values < 0.05). In conclusion, adding the feldspathic sandstone in an appropriate proportion (e.g., 33%) can considerably improve the water retention capacity of aeolian sandy soil in the study area.


2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Karol Fijałkowski ◽  
Rafał Rakoczy ◽  
Anna Żywicka ◽  
Radosław Drozd ◽  
Beata Zielińska ◽  
...  

The aim of the study was to assess the influence of rotating magnetic field (RMF) on the morphology, physicochemical properties, and the water holding capacity of bacterial cellulose (BC) synthetized by Gluconacetobacter xylinus. The cultures of G. xylinus were exposed to RMF of frequency that equals 50 Hz and magnetic induction 34 mT for 3, 5, and 7 days during cultivation at 28°C in the customized RMF exposure system. It was revealed that BC exposed for 3 days to RMF exhibited the highest water retention capacity as compared to the samples exposed for 5 and 7 days. The observation was confirmed for both the control and RMF exposed BC. It was proved that the BC exposed samples showed up to 26% higher water retention capacity as compared to the control samples. These samples also required the highest temperature to release the water molecules. Such findings agreed with the observation via SEM examination which revealed that the structure of BC synthesized for 7 days was more compacted than the sample exposed to RMF for 3 days. Furthermore, the analysis of 2D correlation of Fourier transform infrared spectra demonstrated the impact of RMF exposure on the dynamics of BC microfibers crystallinity formation.


2007 ◽  
Vol 33 (4) ◽  
pp. 231-245
Author(s):  
Christian Nielsen ◽  
Oliver Bühler ◽  
Palle Kristoffersen

Soil water dynamics were studied in 100 street tree planting pits and in the soil surrounding five park trees. Volumetric soil water content and stem cross-sectional area increment were measured on both park and street trees. Different levels of irrigation were implemented on the 100 street trees. Winter assessments of soil wetness at field capacity showed that the water retention capacity was lower in street planting pits than in the park soil attributable to the rather coarse substrate used in the planting pits. High variability among street tree planting pits in regard to water retention capacity was determined and may be related to poor standardization of the substrates, but may also be affected by varying drainage conditions. The rate of water loss in the street tree planting pits was very high immediately after rainfall or irrigation and decreased exponentially during the first 10 days after water input. This was attributed to rapid drainage. The water loss rate in the park soil was on average slightly higher than in the nonirrigated control street pits but showed a more linear decrease over time. We concluded that the water loss in the park soil during summer was primarily driven by transpiration of trees (above 10 L/day [2.6 gal/day]), which complies with common Danish forest experience. The relationship between water loss and tree growth was reversed in the street tree planting pits. The street trees did consume water for growth, but growth and transpiration of the street trees were not a noticeably driving mechanism in the planting pit hydrology. The large variation in street tree increment is attributed to the variation among street planting pits in their ability to retain water. The faster the water loss rate, the slower the tree growth. Irrigation did not prevent final depletion of the soil water resource in planting pits, but irrigation elevated the water content for limited periods during the growing season and thereby enhanced tree growth. Besides the obvious possibilities for improved water balance by horizontal and vertical expansion of the rooting zone, we also suggest improving the water retention capacity of planting pit soil by adding clay nodules. Options for continuous monitoring of tree vitality and soil water content to optimize maintenance are discussed.


2021 ◽  
Vol 29 ◽  
pp. 123-129
Author(s):  
Hao Fu ◽  
V.S. Lyutenko ◽  
V.V. Zhmurko ◽  
R. L. Bohuslavskyi

Aim. On the basis of multivariate analysis, to differentiate einkorn wheat accessions by the water-holding capacity of leaves and ears and the parameters of these organs at the level of species and genotypes. Methods. The water-holding capacity was assessed by the moisture-yielding coefficient which was determined by the method of N.N. Kozhushko (Kozhushko, 1988). Differentiation of einkorn samples was carried out by the method of principal components in the interpretation of A.V. Korosov (Korosov, 1996). Results. Triticum monococcum UA0300113, Syria, and UA0300282, Hungary were characterized by the lowest specific moisture-yielding coefficients: for the second and flag leaves, respectively, (mg / cm2) 10.9, 7.0 and 11.4, 10.7; ears – the same samples as well as Triticum boeoticum UA0300401, Ukraine-Crimea: (mg / cm) 29.6, 28.2, 25.4. With an increase in the size of the lamina, there is a tendency to a decrease in its specific moisture yield. The samples of eincorn are differentiated into 4 clusters corresponding to the species. Conclusions. T. monococcum UA0300113, Syria, and UA0300282, Hungary are relatively drought tolerant. The complex of features characterizing leaf and spike size in combination with the moisture-yielding coefficients processed by the method of principal components makes it possible to differentiate einkorn oaccessions by species and genotype. Keywords: einkorns, moisture yield, drought resistance, leaf, ear.


2020 ◽  
Vol 202 (11) ◽  
pp. 2-13
Author(s):  
Svetlana Denisova ◽  
Antonina Reut

Abstract. Purpose. Study of the effect of anti-stress adaptogens on the water regime of some varieties of chrysanthemum in the conditions of the Bashkir Pre-Urals. Methodology and methods. The analysis of indicators of water regime is based on the method of artificial wilting (V. N. Tarenkov, L. N. Ivanova) and the method of saturation of plant samples (V. P. Moiseev, N. P. Reshetskiy). Plants were processed once, and samples were taken in three terms. Calculations were carried out by standard methods using statistical packages of the Microsoft Excel 2003 and the Agros 2.13. Results. The dynamics of indicators of the water regime during the treatment with the preparations “Gumi-20” and “Oberig” is analyzed. An assessment of the total water content, water retention capacity, daily moisture loss and water deficit of ten varieties of chrysanthemum bred by the South-Ural Botanical Garden-Institute of UFRC RAS (SUBGI UFRC RAS) in the period under study is given. Studies have shown that varieties of chrysanthemum in the Bashkir Ural under the same soil-climatic and agrotechnical conditions had the following indicators: total water content ‒ 69.4–86.9 %, water-holding capacity ‒ 25.6–53.8 %, daily moisture loss ‒ 17.2–61.0 %, water deficit ‒ 10.9–13.2 %. The use of anti-stress adaptogens did not have a significant effect on the parameters of the water regime, or their effect was variety-specific. As a result of the correlation-regression analysis, inverse relationships were revealed between the indicators of water deficit and the total water content, as well as between the daily water loss and water retention capacity. Scientific novelty. For the first time, the water regime of varieties of chrysanthemum of the SUBGI UFRC RAS selection was studied, the dependences of the water regime indicators were revealed, and the assessment of the expediency of using anti-stress adaptogens for certain varieties in the conditions of the Bashkir Pre-Urals was given.


2012 ◽  
Vol 32 (4) ◽  
pp. 775-783 ◽  
Author(s):  
Leandro da Conceição Oliveira ◽  
Maurício Oliveira ◽  
Volnei Luiz Meneghetti ◽  
Simone Mazzutti ◽  
Luciane Maria Colla ◽  
...  

Oats have received attention because of their nutritional characteristics, especially their high-quality content of β-glucan. The drying process reduces water content; therefore they can be preserved for long periods. However, high-temperature drying process may affect the physical, chemical, and functional properties of the grains. The objective of this study was to evaluate the effect of different drying temperatures on β-glucan quality in oat grains. Grains of oats (Avena sativa, L.), cultivar Albasul, harvested at harvest moisture content of 23% were submitted to stationary drying at air temperatures of 25, 50, 75, and 100 ºC until they reached 13% moisture content. The β-glucan content was determined in samples of oat grains and extraction was performed using water as solvent at 90 ºC. The β-glucan extract was evaluated for water holding capacity, water retention capacity, capacity of displacement, and gelation properties. Stationary of oat grains at air temperatures above 25 ºC decreased the water holding capacity, whereas the content of β-glucan and the water retention capacity of β-glucan extract was affected at temperatures above 50 ºC. Physical changes such as increased gelation capacity of the β-glucan extract occurred following drying at air temperature over 75 ºC.


Water ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1674
Author(s):  
Hsin-Fu Yeh ◽  
Tsien-Ting Huang ◽  
Jhe-Wei Lee

Rainfall infiltration is the primary triggering factor of slope instability. The process of rainfall infiltration leads to changes in the water content and internal stress of the slope soil, thereby affecting slope stability. The soil water retention curve (SWRC) was used to describe the relationship between soil water content, matric suction, and the water retention characteristics of the soil. This characteristic is essential for estimating the properties of unsaturated soils, such as unsaturated hydraulic conductivity function and shear strength. Thus, SWRC is regarded as important information for depicting the properties of unsaturated soil. The SWRC is primarily affected by the soil pore size distribution (PSD) and has unimodal and bimodal features. The bimodal SWRC is suitable for soils with structural or dual-porous media. This model can describe the structure of micropores and macropores in the soil and allow the hydraulic behavior at different pore scales to be understood. Therefore, this model is more consistent with the properties of onsite soil. Few studies have explored the differences in the impact of unimodal and bimodal models on unsaturated slopes. This study aims to consider unimodal and bimodal SWRC to evaluate the impact of unsaturated slope stability under actual rainfall conditions. A conceptual model of the slope was built based on field data to simulate changes in the hydraulic behavior of the slope. The results of seepage analysis show that the bimodal model has a better water retention capacity than the unimodal model, and therefore, its water storage performance is better. Under the same saturated hydraulic conductivity function, the wetting front of the bimodal model moves down faster. This results in changes in the pressure head, water content, and internal stress of the soil. The results show that the water content and suction stress changes of the bimodal model are higher than those of the unimodal model due to the difference in water retention capacity. Based on the stability of the slope, calculated using the seepage analysis, the results indicate that the potential failure depth of the bimodal model is deeper than that of the unimodal model.


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