Search

• The increase of potassium(K) promoted total soluble sugar up to 38.3 % under 75 %Ep. • Low water combined with high nitrogen(N) and K achieved the largest irrigation water use efficiency. • The N and K contents in fruits significantly affected yield based on path analysis. • Medium water combined with high N and low K performed best in balancing yield, quality, and efficiency. Appropriate deficit irrigation and nutrient supply are key to efficient agricultural water use in arid and semi–arid regions. An experiment was conducted to evaluate the effects of the combined nitrogen and potassium application on the growth of cherry tomatoes under deficit irrigation across 2021 spring(S) and fall(F). A quadratic orthogonal rotation design with three factors and three levels was adopted, for the following treatments: irrigation levels of W1 (50 % evaporation(Ep)), W2 (75 % Ep), and W3 (100 % Ep); the nitrogen application levels of N1 (S:183.8 kg/ha, F:131.3 kg/ha), N2 (S:367.5 kg/ha, F:262.5 kg/ha), and N3 (S:551.3 kg/ha, F:393.8 kg/ha); and the potassium application levels of K1 (S:98.6 kg/ha, F:70.5 kg/ha), K2 (S:197.3 kg/ha, F:140.9 kg/ha), and K3 (S:295.9 kg/ha, F:211.3 kg/ha). The results revealed that increasing the nitrogen and potassium application significantly promoted the element accumulation in fruits under W1 application, with nitrogen content increasing by 31.6 % and 24.7 %, and potassium content increasing by 25.4 % and 53.7 % in the two study seasons, respectively. When W2 was applied, increased potassium application promoted a 36.2 % and 38.3 % increase in total soluble sugar in the two study seasons, respectively. Nitrate nitrogen residue in the soil showed a downward trend with the deepening of the soil layer. The increased application of nitrogen and potassium enhanced irrigation water use efficiency, but reduced the partial factor productivity of fertilizer. Correlation and path analyses revealed that the application of nitrogen and potassium significantly affected potassium content in fruits, yield, and nitrate nitrogen residue in the 0–15 cm soil layer. The nitrogen and potassium contents in fruits significantly affected yield, with maximum path coefficients of 0.768 and 0.352, respectively. A comprehensive evaluation system consisting of five indicators was constructed, and yield obtained the maximum combined weight of 0.390 and 0.330 in the two seasons, respectively. W2N3K1 exhibited the best balancing in yield, quality, and efficiency based on the TOPSIS model. The proposed strategy offers a theoretical basis for the water–use–efficient and sustainable production of cherry tomatoes in arid and semi–arid regions. [ABSTRACT FROM AUTHOR]

We study a class of real robust phase retrieval problems under a Gaussian assumption on the coding matrix when the received signal is sparsely corrupted by noise. The goal is to establish conditions on the sparsity under which the input vector can be exactly recovered. The recovery problem is formulated as residual minimization in the $\ell _{1}$ -norm. The main contribution is a robust phase retrieval counterpart to the seminal paper by Candes and Tao on compressed sensing ($\ell _{1}$ regression) [Decoding by linear programming. IEEE Transactions on Information Theory, 51(12):4203–4215, 2005]. The analysis depends on a key new property of the coding matrix called the Absolute Range Property (ARP) which is the analogue to the Null Space Property (NSP) in compressed sensing. When the residuals are computed using squared magnitudes, we show that ARP follows from a standard Restricted Isometry Property (RIP). However, when the residuals are computed using absolute magnitudes, a different kind of RIP or growth property is required. We conclude by showing that the robust phase retrieval objectives are sharp with respect to their minimizers with high probability. [ABSTRACT FROM AUTHOR]

The quality of strawberry fruits is a key factor in consumer choice. This study investigated the effect of potassium coupled with water and nitrogen on multiple strawberry fruits quality categories over two growing seasons (from August 2021 to April 2022 and August 2022 to April 2023) in China, to aid in the determination of water and fertilizer decisions based on consumer-orientation. In particular, a composite quadratic orthogonal rotation design with three factors and five levels was adopted to characterize volume water content (W), nitrogen (N) and potassium (K). Twelve quality indicators at three harvest stages were measured respectively. The indicators related to commodity quality, flavor quality and nutritional quality of strawberry fruits were assigned weights based on consumer orientation using analytic hierarchy process. Total soluble solid was regarded as the most important quality indicator with the weight value of 0.1387, followed by single fruit weight (0.1183). All the quality indicators of strawberry fruits were systematically evaluated based on grey relational analysis, and the response model of the comprehensive quality to the combined application of W, N and K was established for each harvest stages. The response trends of consumer-oriented quality were shown as negative parabolas basically to W, N and K in all the three harvests, except a negative linear trend to W in the third harvest and an increased linear to K in the second harvest. Notably, the low level of K supply limited the quality of strawberries, regardless of the input amount of W and N. And the coded values of the optimal combinations for W, N and K were (−0.728, 0, 0.512), (−0.440, 0, 1.682) and (−1.682, 0, 0.834) for the three harvest stages, respectively. By weighting the comprehensive quality based on the corresponding yield of strawberry for the three harvest stages over the two study seasons, the optimal application interval of W, N and K for the entire growth period was determined as: 55.05–76.45%, 3.32 – 4.49 g N/plant and 4.06 – 5.47 g K 2 O/plant, respectively. The results of this experiment provide a theoretical basis for water and fertilizer management, as well as the in-depth research of strawberry. • Total soluble solid was the most important quality indicator for strawberry based on consumer preferences. • The response of comprehensive quality to the water, N and K varied with the harvest time. • The low level of K supply limited the quality, regardless of the input amount of water and N. • Optimal combination of water, N and K was determined for strawberry quality meet to consumer-orientation. [ABSTRACT FROM AUTHOR]

Rising CO 2 concentration in the atmosphere may modulate the response of plants to water and nitrogen, and the existing research is not sufficient to support the fine management of water and nitrogen under CO 2 rise. To determine the optimal water and nitrogen strategy for melon production under CO 2 enrichment in the future, we conducted an experiment with 12 treatments over three growing seasons. The effects of water nitrogen coupling on the yield, quality, and water−nitrogen use efficiency of oriental melon (Cucumis melo L. Qianyu No. 6) under CO 2 enrichment were investigated and evaluated comprehensively. The treatments included two CO 2 concentrations, C 1 (400 ppm) and C 2 (800 ppm), three irrigation levels, I 1 (80% evaporation (Ep)), I 2 (100% Ep), and I 3 (120% Ep); two nitrogen levels, N 1 (S: 184.77 kg ha–1, F: 147.21 kg ha–1) and N 2 (S: 369.54 kg ha–1, F: 294.42 kg ha–1). The result showed that the yield increased with increasing levels of irrigation and nitrogen, and enriched CO 2 significantly increased the yield by 10.3 − 22.9%. N 2 showed a significant promoting effect on the ratio of marketable fruit in the two spring seasons. Enriched CO 2 significantly increased free amino acid of I 1. C 2 coupled with I 1 significantly reduced nitrate content by 30.9%, 14.9% in 2020 F and 2021 S, respectively. The interaction of C*I was significant in irrigation water−use efficiency (IWUE) and nitrogen−use efficiency (NUE). In particular, C 2 coupled with I 2 increased IWUE by 40.5%, 18.7% and NUE by 43.9%, 13.9% in the two spring seasons, respectively. Ten indicators from three categories of yield, quality, and efficiency were used to establish the evaluation system of melon and were comprehensively evaluated based on Fuzzy−Borda model combined three single models. Based on the combined evaluation model, intermediate irrigation combined with higher nitrogen input was best for melon production under CO 2 enrichment. This finding suggested that melon sustainable production should control irrigation and adequately increase nitrogen fertilizer to trade−off fruit, quality, and efficiency for the expected future higher CO 2 concentrations. [Display omitted] • Fuzzy−Borda model was used to balance yield, quality, efficiency of melon. • Enriched CO 2 improved yield by 10.3 − 22.9%. • Enriched CO 2 improved free amino acid of low irrigation in all study seasons. • Intermediate irrigation and higher N input were best for melon under CO 2 enrichment. [ABSTRACT FROM AUTHOR]