Or Sperling

Agricultural Research Organization ARO | aro

Mango's irrigation is typically applied regardless of the fertigation regime, mostly due to a lack of knowledge regarding the fertigation effect on plants' water uptake. From 2017 to 2020, we investigated the seasonal dynamics of mango's water uptake using flushing lysimeters under five different nitrogen (N) fertigation treatments: 2, 10, or 20 mg...

Precision fertilization is crucial for sustainable and efficient world farming. However, traditional chemical mineral analyses are costly and time-consuming, which limits the amount of data that can be collected and...

Recent economic, environmental, and regulative concerns force farmers to precise their fertilization practices. Yet, a critical knowledge gap concerning the temporal variability in perennials’ nutritional requirements renders most fertilization applications inefficient. While mass balance studies could illustrate the dynamics of crops’ mineral upta...

Irrigation's mineral composition affects plants’ water utilization. However, limited data concerning minerals’ interactive effects on transpiration hinder the integration of the mineral matrix into irrigation planning. Hence, we set to (1) characterize the effects of mineral availability on almond trees’ transpiration and (2) integrate climatic var...

Jojoba (Simmondsia chinensis (Link) Schneider) holds high industrial value and an extended cultivation trend. Despite its increased importance, there is a lack of fundamental information about its metabolic reserves and development. Our objective was to characterise metabolite allocation and fluctuations in the carbohydrate and nutrient balance of...

Precise phosphorus (P) application requires a mechanistic understanding of mineral effects on crops' biology and physiology. Photosynthates assimilation, metabolism, and transport require phosphorylation, and we postulated that P is critical for the bloom and fruit-set of almond trees that rely on stored carbohydrate reserves. Hence, we studied the...

Plants in temperate environments experience periods with minimal photosynthetic capacity, be it winter chills or summer droughts. Hence, perennial plants manage an annual energetic cycle of non-structural carbohydrates that regularly sustains metabolism. Plants also sync their phenological shifts with the seasonal carbohydrate availability to ensur...

Precise nitrogen (N) fertilization requires new indices of plants’ nutritional status. Non-structural carbohydrates (NSC) are the energetic currency of plants and can, thus, serve as a physiological indicator for their condition. Nevertheless, only a few records exist about NSC composition and allocation in crops, and their relationship with N upta...

Precise nitrogen (N) fertilization requires new indices of plants’ nutritional status. Non-structural carbohydrates (NSC) are the energetic currency of plants and can, thus, serve as a physiological indicator for their condition. Nevertheless, only a few records exist about NSC composition and allocation in crops, and their relationship with N upta...

Mineral fertilization through irrigation (fertigation) could optimize resource allocation and eliminate wastes in agriculture. Nevertheless, the fertigation of almond plantations is currently inefficient (50% nitrogen (N) recovery by yields) due to the limited empirical data to support field applications. For precise fertigation in horticulture, we...

Plants optimize water use and carbon assimilation via transient regulation of stomata resistance and by limiting hydraulic conductivity in a long‐term response of xylem anatomy. We postulated that without effective hydraulic regulation plants would permanently restrain water loss and photosynthetic productivity under salt stress conditions. We comp...

Despite non-structural carbohydrate (NSC) importance for tree productivity and resilience, little is known about their seasonal regulations and trade-off with growth and reproduction. We characterize the seasonal dynamics of NSC in relation to the aboveground phenology and temporal growth patterns of three deciduous Mediterranean species: almond (P...

Cassava (M. esculenta Crantz), feeding countless people and attracting markets worldwide, is a model for traditional crops that need physiology-based fertigation (fertilization through irrigation) standards in intensive cultivation. Hence, we studied the effects of 10 to 200 mg L-1 nitrogen (N) fertigation on growth and yields of cassava and target...

Horticulture nitrogen (N) runoffs are major environmental and health concerns, but current farming practices cannot detect ineffective N applications. Hence, we set to recognize high N conditions and characterize their effects on the physiology of almond trees grown in drainage lysimeters. Water and nutrients mass balances exhibited that N benefitt...

A typical olive (Olea europaea L.) inflorescence consists of about 20 flowers. However, in many cultivars, only one fruit develops. This is due to massive abscission of flowers and fruitlets, which occurs during the first month after anthesis. In this study, we used the olive cultivar 'Barnea' to characterize the abscission mechanism and to try to...

Inexpensive determination of starch and total soluble sugar levels in plant tissues

Main conclusion: During spring, bud growth relies on long-distance transport of remotely stored carbohydrates. A new hypothesis suggests this transport is achieved by the interplay of xylem and phloem. During the spring, carbohydrate demand of developing buds often exceeds locally available storage, thus requiring the translocation of sugars from...

Trees experience two distinct environments: thermally-variable air and thermally-buffered soil. This generates intra-tree temperature gradients, which can affect carbon metabolism and water transport. In this study, we investigated whether carbohydrate allocation within trees is assisted by temperature gradients. We studied pistachio (Pistacia inte...

Main conclusionCold acclimation is revealed through induced stem respiration during pre-winter frost of nativePistacia integerrimatrees in continental semi-arid environments. Semi-arid environments challenge vegetation by simultaneous abiotic stresses. In this study, we examine the combined effects of water stress and frost on the physiology of Pis...

The arid and semi-arid drylands of the world are increasingly recognized for their role in the terrestrial net carbon dioxide (CO2) uptake, which depends largely on plant litter decomposition and the subsequent release of CO2 back to the atmosphere. Observed decomposition rates in drylands are higher than predictions by biogeochemical models, which...

Cellular respiration depletes stored carbohydrates during extended periods of limited photosynthesis, e.g. winter dormancy or drought. As respiration rate is largely a function of temperature, the thermal conditions during such periods may affect non-structural carbohydrate (NSC) availability and, ultimately, recovery. Here, we surveyed stem respon...

Respirational response to a change in temperatures of 11 organisms presented in Fig 1A and their bibliographic references. (DOCX)

Percent increase from the projected stem respiration at -2°C in P. integerrima saplings and excised segments showed no significant differences between the methods (unpaired two-ways T-test, p>0.68, df = 9). (DOCX)

Coastal redwood (Sequoia sempervirens), the world's tallest tree species, rehydrates leaves via foliar water uptake during fog/rain events. Here we examine if bark also permits water uptake in redwood branches, exploring potential flow mechanisms and biological significance. Using isotopic labeling and microCT imaging, we observed that water entere...

During the summer, evaporative demand at midday often exceeds the transport capacity of most desert plants. However, date palms maintain their ecological dominance with sustained and uniquely high rates of transpiration. This high rate of flow cannot be attributed to soil water supply alone. In order to quantify intra-plant water allocation in irri...

Irrigation of crops in arid regions with marginal water is expanding. Due to economic and environmental issues arising from use of low-quality water, irrigation should follow the actual crop water demands. However, direct measurements of transpiration are scant, and indirect methods are commonly applied; e.g., the Penman–Monteith (PM) equation that...

In a world of diminishing water reservoirs and a rising demand for food, the practice and development of water stress indicators and sensors are in rapid progress. The heat dissipation method, originally established by Granier, is herein applied and modified to enable sap flow measurements in date palm trees in the southern Arava desert of Israel....

Soil water moments are a set of statistical characteristics calculated from the water-content values of a soil profile. The moments indicate the water's center of mass location on the x and z axes and the water distribution around those axes, thereby producing a clear and unique temporal and spatial description of water location using only four par...