Determination of Local Barley (Hordeum Vulgare) Crop Coefficient and Comparative Assessment of Water Productivity for Crops Grown Under the Present Pond Water in Tigray, Northern Ethiopia

SUMMARYAquaCrop, the FAO water productivity model, is used as a tool to predict crop production under water limiting conditions. In the first step AquaCrop was calibrated and validated for barley (Hordeum vulgare L.). Data sets of field experiments at seven different locations in four countries (Ethiopia, Italy, Syria and Montana, USA) with different climates in different years and with five different cultivars were used for model calibration and validation. The goodness-of-fit between observed and simulated soil water content, green canopy cover, biomass and grain yield was assessed by means of the coefficient of determination (R2), the Nash–Sutcliff efficiency (E), the index of agreement (d) and the root mean square error (RMSE). The statistical parameters indicated an adequate accuracy of simulations (validation regression of yield: R2 = 0.95, E = 0.94, d = 0.99, RMSE = 0.34). Subsequently, sowing strategies in the semi-arid environment of northern Ethiopia were evaluated with the validated model. Dry sowing had a probability of 47% germination failure attributable to false start of the rainy season. On the other hand, delay sowing at the start of the rainy season to eliminate germinating weeds should be kept as short as possible because grain yields strongly reduce in the season due to water stress when sowing is delayed on shallow soils. This research demonstrates the ability of AquaCrop to predict accurately crop performance with only a limited set of input variables, and the robustness of the model under various environmental and climatic conditions.

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Cereals and cereal products. Determination of Besatz in wheat (Triticum aestivum L.), durum wheat (Triticum durum Desf.), rye (Secale cereale L.) and feed barley (Hordeum vulgare L.)

10.3403/30156349 ◽

2008 ◽

Keyword(s):

Triticum Aestivum ◽

Hordeum Vulgare ◽

Secale Cereale ◽

Triticum Durum ◽

Triticum Aestivum L ◽

Hordeum Vulgare L ◽

Cereal Products ◽

Secale Cereale L ◽

Triticum Durum Desf

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Comparative assessment of informational content of the equations of F.P. Hadlock and the computer program of V.N. Demidov in determination of term of gestation and fetal weight in the III trimester of gestation

10.21516/2413-1458-2017-16-2-145-150 ◽

2017 ◽

Author(s):

E.A. Derkach , O.I. Guseva

Keyword(s):

Computer Program ◽

High Precision ◽

Gestational Age ◽

Computer Programs ◽

Comparative Assessment ◽

Fetal Weight ◽

Informational Content ◽

Third Trimester ◽

The Third

Objectives: to compare the accuracy of equations F.P. Hadlock and computer programs by V.N. Demidov in determining gestational age and fetal weight in the third trimester of gestation. Materials: 328 patients in terms 36–42 weeks of gestation are examined. Ultrasonography was performed in 0–5 days prior to childbirth. Results: it is established that the average mistake in determination of term of pregnancy when using the equation of F.P. Hadlock made 12,5 days, the computer program of V.N. Demidov – 4,4 days (distinction 2,8 times). The mistake within 4 days, when using the equation of F.P. Hadlock has met on average in 23,1 % of observations, the computer program of V.N. Demidov — 65,9 % (difference in 2,9 times). The mistake more than 10 days, took place respectively in 51,7 and 8,2 % (distinction by 6,3 times). At a comparative assessment of size of a mistake in determination of fetal mass it is established that when using the equation of F.P. Hadlock it has averaged 281,0 g, at application of the computer program of V.N. Demidov — 182,5 g (distinction of 54 %). The small mistake in the mass of a fetus which isn't exceeding 200 g at application of the equation of F.P. Hadlock has met in 48,1 % of cases and the computer program of V.N. Demidov — 64,0 % (distinction of 33,1 %). The mistake exceeding 500 g has been stated in 18 % (F.P. Hadlock) and 4,3 % (V.N. Demidov) respectively (distinction 4,2 times). Conclusions: the computer program of V.N. Demidov has high precision in determination of term of a gestation and mass of a fetus in the III pregnancy.

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THE WATER RELATIONS AND IRRIGATION REQUIREMENTS OF SUGAR CANE (SACCHARUM OFFICINARUM): A REVIEW

Experimental Agriculture ◽

10.1017/s0014479710000645 ◽

2011 ◽

Vol 47 (1) ◽

pp. 1-25 ◽

Cited By ~ 47

Author(s):

M. K. V. CARR ◽

J. W. KNOX

Keyword(s):

Water Stress ◽

Water Relations ◽

Sugar Cane ◽

Root Zone ◽

Water Productivity ◽

Crop Coefficient ◽

Saccharum Officinarum ◽

Irrigation Scheduling ◽

Background Information ◽

Technology Choice

SUMMARYThe results of research on the water relations and irrigation needs of sugar cane are collated and summarized in an attempt to link fundamental studies on crop physiology to irrigation practices. Background information on the centres of production of sugar cane is followed by reviews of (1) crop development, including roots; (2) plant water relations; (3) crop water requirements; (4) water productivity; (5) irrigation systems and (6) irrigation scheduling. The majority of the recent research published in the international literature has been conducted in Australia and southern Africa. Leaf/stem extension is a more sensitive indicator of the onset of water stress than stomatal conductance or photosynthesis. Possible mechanisms by which cultivars differ in their responses to drought have been described. Roots extend in depth at rates of 5–18 mm d−1 reaching maximum depths of > 4 m in ca. 300 d providing there are no physical restrictions. The Penman-Monteith equation and the USWB Class A pan both give good estimates of reference crop evapotranspiration (ETo). The corresponding values for the crop coefficient (Kc) are 0.4 (initial stage), 1.25 (peak season) and 0.75 (drying off phase). On an annual basis, the total water-use (ETc) is in the range 1100–1800 mm, with peak daily rates of 6–15 mm d−1. There is a linear relationship between cane/sucrose yields and actual evapotranspiration (ETc) over the season, with slopes of about 100 (cane) and 13 (sugar) kg (ha mm)−1 (but variable). Water stress during tillering need not result in a loss in yield because of compensatory growth on re-watering. Water can be withheld prior to harvest for periods of time up to the equivalent of twice the depth of available water in the root zone. As alternatives to traditional furrow irrigation, drag-line sprinklers and centre pivots have several advantages, such as allowing the application of small quantities of water at frequent intervals. Drip irrigation should only be contemplated when there are well-organized management systems in place. Methods for scheduling irrigation are summarized and the reasons for their limited uptake considered. In conclusion, the ‘drivers for change’, including the need for improved environmental protection, influencing technology choice if irrigated sugar cane production is to be sustainable are summarized.

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Hemodynamic control using models of electroacoustic signals of an oxygenated neuron

Доклады Адыгской (Черкесской) Международной академии наук ◽

10.47928/1726-9946-2021-21-3-50-54 ◽

2021 ◽

Vol 21 (3) ◽

pp. 50-54

Author(s):

B.G. Tsugkiev ◽

◽

L.Ch. Gagieva ◽

T.V. Tsugkieva ◽

M.M. Chegaev ◽

...

Keyword(s):

Heavy Metals ◽

Nutritional Value ◽

Growing Season ◽

Comparative Assessment ◽

Biologically Active ◽

Onobrychis Viciifolia ◽

Iron Copper ◽

Calcium Phosphorus ◽

Active Substances

The paper presents a comparative assessment of the nutritional value depending on the phenological phase of Onobrychis viciifolia Scop., as well as the determination of the regularity of the accumulation of biologically active substances and heavy metals in the herb of the species. The yield of green mass of plants was determined. From each hectare of sowing, 9,7 centners of protein can be obtained; the yield of fiber is 13 centners, BEV is 22,9 centners, fat is 1,6 centners, ash is 4 centners and carotene is 13.0 kg. Depending on the growing season, the chemical composition in the grass of Onobrychis viciifolia changes. The content of calcium, phosphorus increases, and the presence of iron, copper, cobalt, zinc, manganese and molybdenum and amino acids decreases.

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