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Improved the utilization of fertilizer while maintaining the increased of grain yield was the focus of Chinese researchers. Nutrient uptake, distribution, and remobilization are important factors affecting the fertilizer utilization and grain yield of maize. This study aimed to provide a theoretical and practical basis for science-based, high-yielding, and high-efficiency cultivation practices by examining differences in biomass and nutrient uptake, distribution, and remobilization characteristics under three cultivation patterns. We set 12 treatments as follows: super high-yielding cultivation pattern (SH), optimized nutrient management cultivation pattern (ONM), local farmer's practice cultivation pattern (FP), and a series of nutrient omission plots, which excluded nitrogen (N), phosphorus (P), or potassium (K) from the three patterns. The results demonstrated that SH and ONM increased the yield and actual harvested ears by 35.4, 20.7 and by 20.2, 17.6%, respectively. Compared with the FP, SH and ONM increased biomass, N, P, and K accumulation at silking (R1 stage) by 24.4, 31.2, 39.4, and 34.8%, and by 21.7, 22.2, 31.7, and 34.8%, respectively. SH and ONM significantly increased biomass and nutrient distribution to the grains. ONM significantly increased N use efficiency. P and K use efficiency under the ONM pattern was significantly higher than under SH, but was lower than under the FP pattern over two years. This research demonstrates that ONM may significantly reduce fertilizer rates, effectively improve the nutrient remobilization efficiency and uptake at post-silking without negatively affecting grain yield, thereby increasing N use efficiency. [ABSTRACT FROM AUTHOR]

In pursuit of maximum grain yield farmers in the North China Plain usually apply excessive N fertilizer, resulting in wasted resources and environmental pollution. To assess the economic and environmental performances of different nitrogen rates will be conductive to sustain cleaner crop production. An 8-year field experiment was carried out with four treatments, N0 (0 kg ha−1 for winter wheat and summer maize), N1 (168 kg ha−1 for winter wheat and 129 kg ha−1 for summer maize), N2 (240 kg ha−1 for winter wheat and 185 kg ha−1 for summer maize) and N3 (300 kg ha−1 for winter wheat and summer maize), on the double cropping at Dawenkou research field (36°11'N, 117°06'E), Shandong Province, China. The crop production, soil physical-chemical parameters, and greenhouse gas emission are measured and the economic and environmental performances are assessed. The optimal nitrogen rate obtained the highest grain yield of summer maize in 4 of 8 year and was equivalent to conventional N rate in the other years. The nitrogen partial factor productivity and agronomic efficiency of optimal nitrogen rate was 63% and 58% higher than that of conventional nitrogen rate. The optimal nitrogen rate effectively decreased soil bulk density and increased weight percentage of water-stable aggregate and activities of urease and invertase compared to conventional nitrogen rate, which improved soil productivity. The fertilizer nitrogen loss and global warming potential of optimal nitrogen rate reduced by 76% and 35% compared to conventional nitrogen rate. The annual greenhouse gas intensity of optimal nitrogen rate decreased by 14–35% compared to others. The net ecosystem economic budget under optimal nitrogen rate is 252–604 $ ha−1 yr.−1 higher than other addition levels. The optimal nitrogen rate produces more grains and obtains higher economic and environmental benefits. [ABSTRACT FROM AUTHOR]

Agrotis ipsilon (Lepidoptera: Noctuidae) is a major underground pest that damages many agricultural crops in China and other countries. A diet-incorporation-based bioassay was conducted to evaluate the sublethal effects of the novel anthranilic diamide chlorantraniliprole on the nutritional physiology, enzymatic properties and population parameters of this cutworm. Chlorantraniliprole exhibited signs of active toxicity against third instar larvae of A. ipsilon, and the LC50 was 0.187 μg.g−1 of artificial diet after treatment for 72 h. The development time of the larval, pupal and adult stages was significantly affected after chlorantraniliprole exposure, compared to the control treatment. Relative to the control treatment, chlorantraniliprole decreased pupal and adult emergence rates, fecundity and fertility and increased the proportions of developmental deformities, the adult preoviposition period (APOP) and the total preoviposition period (TPOP). Furthermore, compared to those treated with the control, A. ipsilon larvae treated with low doses of chlorantraniliprole decreased food utilization and nutrient content (protein, lipid, carbohydrate, trehalose), showed lower pupal weights and growth rates. Compared with the control treatment, chlorantraniliprole significantly reduced digestive enzyme activities and observably increased detoxifying and protective enzyme activities and hormone titers. Importantly, these chlorantraniliprole-induced changes affected life table parameters of the cutworm. These results suggest that chlorantraniliprole at low concentrations can impair A. ipsilon development duration, normal food consumption and digestion process, enzymatic properties, hormone levels, fecundity and population levels. Chlorantraniliprole exhibit the potential to be exploited as a control strategy for this cutworm. [ABSTRACT FROM AUTHOR]

Various literatures have demonstrated that overexpression of Metadherin (MTDH) is correlated with tumor metastasis and it can predict poor survival outcomes in female reproduction malignancies. In order to enhance the statistical power and reach a recognized conclusion, we conducted a systematic review and meta-analysis to thoroughly investigate the association of MTDH expression with tumor metastasis and survival outcomes following PRISMA guidelines. Odds ratios (ORs) and hazard ratios (HRs) were used to demonstrate the impact of MTDH on tumor metastasis and prognosis respectively. Data were pooled with appropriate effects model on STATA12.0. Our results indicated that high MTDH expression is significantly correlated with higher mortality for breast, ovarian and cervical cancer. High immunohistochemical expression of MTDH is remarkably associated with shorter disease-free survival (DFS) in breast cancer but not in ovarian cancer. The pooled results suggested that high level of MTDH significantly predicted distant metastasis and lymph node metastasis in breast cancer. Strong associations were observed between MTDH expression and lymph node metastasis in ovarian and cervical cancer. In conclusion, MTDH might be a novel biomarker which can effectively reflect metastasis status and prognosis of breast cancer. However, its application in clinical practice needs more prospective studies with large samples. [ABSTRACT FROM AUTHOR]