Genetic diversity of sugar beet under heat stress and deficit irrigation

In the light of climate changes and globalwarming, as well as the rapid expansion in sugar beet (Beta vulgaris L.) cultivation in Egypt, the development of sugar beet varieties with improved tolerance to high temperature and deficit irrigation is of great importance. The objective of this studywas to evaluate sugar beet genotypes under high temperatures and deficit irrigation conditions for further identification and selection of heat and drought tolerant genotypes. In the current study, a panel of 18 sugar beet breeding lines produced at the USDA–ARS–NWISRL, Kimberly, ID, and the commercial sugar beet cultivar Kawimera were evaluated for yield and quality under high temperature. Six promising lines in terms of yield and quality were further evaluated under both high temperature and deficit irrigation for two growing seasons. All lines performed differently under deficit irrigation, indicating a high degree of genetic variability in the evaluated lines. Additionally, yield traits showed negative effect due to deficit irrigation. A significant positive correlation was observed between stress tolerance index (STI), and average root and sugar yields under stressed and non-stressed conditions. A linear relationship between STI and average root and sugar yields indicates that STI is a reliable stress index to select high yielding genotypes under both optimum- and deficit-irrigation conditions. USKPS25 and USC944-6-68 breeding lines are most likely adapted to deficit irrigation and high temperature and suitable to be utilized in the proposed sugar beet breeding programs in Egypt

Hydrothermal Carbonization Technology for Wastewater Treatment under the “Dual Carbon” Goals: Current Status, Trends, and Challenges

Hydrothermal carbonization (HTC) technology transforms organic biomass components, such as cellulose and lignin, into valuable carbon materials, gases and inorganic salts through hydrolysis, degradation and polymerization, with significant advantages over traditional methods by reducing energy consumption, lowering pollutant emissions and enhancing carbonization efficiency. In the context of global climate change, HTC plays a critical role in water environment management by addressing industrial, agricultural, and domestic wastewater challenges. The application of HTC extends to wastewater treatment, where hydrochar effectively adsorbs heavy metals, organic compounds, and anions, thereby improving water quality. However, challenges remain, such as optimizing the process for diverse raw materials, managing economic costs, and addressing environmental and social impacts. Future research and policy support are essential for advancing HTC technology. By enhancing reaction mechanisms, developing catalysts, and promoting international cooperation, HTC can significantly contribute towards achieving carbon neutrality goals and fostering sustainable development

Modeling of Phosphorus Nutrition to Obtain Maximum Yield, High P Use Efficiency and Low P-Loss Risk for Wheat Grown in Sandy Calcareous Soils

Fertilization with high levels of phosphorus increases the risk of environmental pollution. Identification of critical values of P in soil (SOP) and in plant tissues (PiP) is essential for achieving the maximum wheat yield without P loss. The critical value is the value of P which gives the optimum yield; the response of crop yield to P fertilization above this value is not predictable or nil. Here, a 4-year field experiment was conducted to identify the SOP and PiP for achieving maximum yield of bread wheat using 11 rates of P fertilization (0, 15, 30, 45, 60, 75, 90, 105, 120, 135, and 150 kg P2O5 ha−1). The linear–linear and Mitscherlich exponential models were employed to estimate the PiP and SOP. The degree of phosphorus saturation (DPS) was used to assess the potential environmental risk; furthermore, phosphorus use efficiency (PUE) was also calculated under the studied fertilization levels. Phosphorus in soil and wheat plant was affected by the application rates and growing seasons. Increasing P fertilization rates led to gradual increases in soil and plant P. The SOP ranged between 21 and 32 mg kg−1, while the PiP ranged between 6.40 and 7.49 g kg−1. The critical values of P calculated from the Mitscherlich exponential models were 20% higher than those calculated from the linear–linear models. Adding levels of P fertilization ≥90 kg P2O5 ha−1 leads to higher potentials of P runoff and leaching, in addition, PUE decreased sharply under high P fertilization levels. The response of wheat yield to P fertilization in sandy calcareous soil is predictable below Olsen P values of 21 mg kg−1. Identification of critical P values for wheat production is of great importance to help policy makers improve P use efficiency and attain optimum wheat yield under eco-friendly environmental conditions by eliminating the accumulation of excess P fertilizers in soil and water

Conservation and divergence of autonomous pathway genes in the flowering regulatory network of Beta vulgaris

The transition from vegetative growth to reproductive development is a complex process that requires an integrated response to multiple environmental cues and endogenous signals. In Arabidopsis thaliana, which has a facultative requirement for vernalization and long days, the genes of the autonomous pathway function as floral promoters by repressing the central repressor and vernalization-regulatory gene FLC. Environmental regulation by seasonal changes in daylength is under control of the photoperiod pathway and its key gene CO. The root and leaf crop species Beta vulgaris in the caryophyllid clade of core eudicots, which is only very distantly related to Arabidopsis, is an obligate long-day plant and includes forms with or without vernalization requirement. FLC and CO homologues with related functions in beet have been identified, but the presence of autonomous pathway genes which function in parallel to the vernalization and photoperiod pathways has not yet been reported. Here, this begins to be addressed by the identification and genetic mapping of full-length homologues of the RNA-regulatory gene FLK and the chromatin-regulatory genes FVE, LD, and LDL1. When overexpressed in A. thaliana, BvFLK accelerates bolting in the Col-0 background and fully complements the late-bolting phenotype of an flk mutant through repression of FLC. In contrast, complementation analysis of BvFVE1 and the presence of a putative paralogue in beet suggest evolutionary divergence of FVE homologues. It is further shown that BvFVE1, unlike FVE in Arabidopsis, is under circadian clock control. Together, the data provide first evidence for evolutionary conservation of components of the autonomous pathway in B. vulgaris, while also suggesting divergence or subfunctionalization of one gene. The results are likely to be of broader relevance because B. vulgaris expands the spectrum of evolutionarily diverse species which are subject to differential developmental and/or environmental regulation of floral transition.Peer reviewedFinal Published versio