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Controversy exists regarding the distraction resistance of priority items in visual working memory (VWM). The protection account proposes that high‐priority items resist distraction more than low‐priority items, while the vulnerability account proposes that distractors impair high‐priority items more. We proposed another available resource threshold account: distraction will not impair items if available resources exceed their threshold needed for sufficient processing. Using a change‐detection paradigm, we manipulated item priority by color similarity and inserted distractors during VWM retention. We investigated the effect of similarity on distraction resistance of relevant (color) and irrelevant (shape) feature representations (Experiments 1–2), and the neural mechanism of this effect using event‐related potentials (ERPs; Experiment 3). Behavioral results showed distractors impaired the accuracy of dissimilar items when relevant features were memorized and of similar items when irrelevant features were memorized under simultaneous presentation of similar and dissimilar items. Moreover, distractors impaired the accuracy of dissimilar items when relevant features were memorized and of both similar and dissimilar items when irrelevant features were memorized under separate presentation of items. ERP results showed a smaller negative slow wave and P2 but larger N2 under the similar condition. Similarity protected relevant features of similar items against distraction by reducing memory load, decreasing attentional resources allocated to distractors, and strengthening inhibition of distractors. However, similarity did not protect irrelevant features of similar items. Our results support the available resource threshold account, suggesting that VWM is a flexible and intelligent system despite its limited capacity. To reconcile the controversy over distraction resistance of high‐priority items in visual working memory, we proposed and provided evidence for an available resource threshold account. This account claims that the distraction resistance of high‐priority items depends on whether available resources of the items exceed the required resource threshold needed for their sufficient processing or not. [ABSTRACT FROM AUTHOR]

Rational water and fertiliser management have an important impact on alfalfa production. This research aimed to explore the effects of water and phosphorus (P) fertiliser on water‐use efficiency (WUE) and phosphorus‐recovery efficiency (PRE) of each cut of alfalfa under drip irrigation and to determine the optimal interaction ratio of water and phosphorus to improve the quality and yield of alfalfa. Different irrigation levels were set, i.e., 5250, 6000 and 6750 m3/ha (referred to as W1, W2, W3, respectively), and P fertiliser levels (0, 50, 100 and 150 kg/ha P2O5 referred to as P0, P1, P2, P3, respectively) were set to determine the hay yield and nutrient quality of each cut of alfalfa under drip irrigation. The hay yield of each cut of alfalfa increased first and then decreased with increased P fertiliser under the same irrigation amount. WUE decreased gradually with an increasing amount of irrigation under the same P application rate. The WUE of alfalfa increased first and then decreased with the increase of P application rate under the same irrigation amount, and WUE was 0.20%–4.75% (2016) and 1.31%–6.22% (2017) higher in the P treatments than in the non‐phosphorus treatments. PRE decreased gradually with increasing P application rate under the same irrigation amount. Therefore, we concluded that moderate irrigation (6000 m3/ha) and P fertiliser (100 kg/ha) optimised WUE, PRE, hay yield and nutrient quality. [ABSTRACT FROM AUTHOR]

Appropriate fertilization is an important management practice for optimizing the nutritional quality and increasing the phosphorus use efficiency (PUE) of field‐grown alfalfa (Medicago sativa L.). A 2‐yr field experiment in 2017 and 2018 in Xinjiang, China, involving fertilization with different amounts of N (0, 105, and 210 kg ha−1, referred to as N0, N1, and N2, respectively) and P (0, 50, 100, and 150 kg ha−1, referred to as P0, P1, P2, and P3, respectively) was established and resulted in the production of high‐quality alfalfa under drip irrigation. The crude protein (CP) content in the N1 treatment was greater than that in the N2 treatment under the P0, P2, and P3 treatments. Compared with that in the N1P0 and N2P3 treatments, the relative feed value (RFV) in the N1P2 treatment increased by 9−21% and 8−18%, respectively. The annual total CP yield in the N1P2 treatment was the greatest. Compared with that in the N1P3 treatment, the total PUE in the N1P2 treatment increased by 76.69−99.69%. At each clipping, the CP yield and PUE of alfalfa were significantly different between the N and P treatments. Therefore, we conclude that when N was applied at 105 kg ha−1 and P was applied at 100 kg ha−1, alfalfa presented the greatest nutritional quality and PUE under drip irrigation. [ABSTRACT FROM AUTHOR]

Alfalfa (Medicago sativa L.) is an important forage legume in arid areas, but limited water resources and low fertilizer utilization have restricted its agricultural development. Meanwhile, studies on the effects of integrated water and phosphorus on production performance and water‐use efficiency and phosphorus‐use efficiency of alfalfa, especially on hay yield, phosphorus accumulation, and total phosphorus uptake are rarely reported under drip irrigation. The treatments were a factorial combination of three irrigation rates (5,250, 6,000, and 6,750 m3/ha per year) and four P rates (0, 50, 100, and 150 kg/ha per year) and consisted of 12 treatments for water and P management, arranged in a randomized complete block design with three replicates. Total hay yield and water‐use efficiency and phosphorus‐use efficiency of alfalfa in P2 treatment were significantly greater than those in the P1 and P3 treatments (p <.05), and the total hay yield of alfalfa with phosphorus application increased by 7.43%–29.87% compared with that in the nonphosphorus (P0) treatment under the same irrigation amount. The total phosphorus and available phosphorus concentrations in the 0–20 cm soil layer were greater than those in the 20–40 cm and 40–60 cm soil layers compared with those in the P0 treatment. Correlation analyses showed that total hay yield was significantly positively correlated with total phosphorus uptake and water‐use efficiency (p <.01). The accumulated phosphorus concentration was significantly positively correlated with total phosphorus and available phosphorus concentration (p <.01) and was positively correlated with the phosphorus‐use efficiency (p <.05). The membership function method was used to evaluate all the indicators, and the three treatments that had the greatest influence on the production performance of alfalfa were, in order, W2P2 > W3P2 > W1P2. Therefore, an irrigation rate of 6,000 m3/ha and a phosphorus application rate of 100 kg/ha per year should be considered as the best management for both high yield and water‐use efficiency and phosphorus‐use efficiency of alfalfa. [ABSTRACT FROM AUTHOR]