[Response of grain filling characteristics of maize to sowing date.] / 玉米籽粒灌浆特性对播期的响应.

To study the effect of different sowing dates on the process of grain filling characteristics, Jingke 528 (JK528) and Zhengdan 958 (ZD958) were used in the field experiment with two sowing dates (10th April and 14th May). The results showed that the 100-grain dry mass and yield of JK528 and ZD958 with the early spring sowing were significantly higher than that with the spring sowing date, which increased by 6.8% and 10.1%, 17.8% and 9.2%, respectively. The maximum grain filling rate (Gmax) and the average grain filling rate (Gave) were higher with the early spring sowing than that with the spring sowing date, while the active grain filling period (P) showed an opposite trend. The 100-grain mass and yield of JK528 were significantly improved by 7.4 g and 1189.6 kg·hm-2 compared to ZD958, with the increase of 21.6% and 10.8%, respectively. The P of ZD958 was higher than that of JK528, while Wmax, Gmax, Gave and Tmax of JK528 were higher than that of ZD958. The average grain filling rate of JK528 during early and mid grain filling stages was higher than that of late grain filling stages, which was also higher than that of ZD958 at the same sowing date. Furthermore, correlation analysis revealed that the mean temperature and the accumulated temperature were significantly positively correlated with the grain dry matter accumulation. Therefore, the full use of hot-ray resources and the increase of the mean grain-filling rate could improve maize grain yield. The higher grain filling rate during early and mid grain filling stages in JK528 could compensate for the short active grain filling period, leading to higher yields under different sowing dates.

Tanshinone IIA therapeutically reduces LPS-induced acute lung injury by inhibiting inflammation and apoptosis in mice.

AIM: To study the effects of tanshinone IIA (TIIA) on lipopolysaccharide (LPS)-induced acute lung injury in mice and the underlying mechanisms. METHODS: Mice were injected with LPS (10 mg/kg, i.p.), then treated with TIIA (10 mg/kg, i.p.). Seven hours after LPS injection, the lungs were collected for histological study. Protein, LDH, TNF-α and IL-1ß levels in bronchoalveolar lavage fluid (BALF) and myeloperoxidase (MPO) activity in lungs were measured. Cell apoptosis and Bcl-2, caspase-3, NF-κB and HIF-1α expression in lungs were assayed. RESULTS: LPS caused marked histological changes in lungs, accompanied by significantly increased lung W/D ratio, protein content and LDH level in BALF, and Evans blue leakage. LPS markedly increased neutrophil infiltration in lungs and inflammatory cytokines in BALF. Furthermore, LPS induced cell apoptosis in lungs, as evidenced by increased TUNEL-positive cells, decreased Bcl-2 content and increased cleaved caspase-3 content. Moreover, LPS significantly increased the expression of NF-κB and HIF-1α in lungs. Treatment of LPS-injected mice with TIIA significantly alleviated these pathological changes in lungs. CONCLUSION: TIIA alleviates LPS-induced acute lung injury in mice by suppressing inflammatory responses and apoptosis, which is mediated via inhibition of the NF-κB and HIF-1α pathways.