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Slow-release N fertilizer is considered an eff ective method of improving the N use effi ciency (NUE). To investigate yield and N uptake of bowl-seedling machine-transplanted rice (Oryza sativa L.) with slow-release N fertilizer, three fertilizers treatments including slow-release fertilizer blend (SFB), polymercoated urea (PCU), and sulfur-coated urea (SCU), and two fertilizer methods including single basal application (B), and combined with tillering urea (BT) were performed from 2013 to 2014 in Jiangsu Yellow Sea Farm of China. Conventional split fertilization (CK) and zero N treatment (N0) are controls. Yield and NUE improvement was found in PCU under both fertilization methods in both years when compared with the CK. Th e SCU only showed a slight yield increase in 2014, while SFB increased the yields and NUEs under both fertilization methods in both years. Th e BT-SFB got the highest yields as 13.6 and 13.3 Mg ha -1 , as well as increased 7.9 and 10.8% compared with CK in both years, respectively. Th e recovery effi ciency of N was also the highest for BT-SFB with 52.7 and 38.5% for 2013 and 2014, respectively. Th e results indicated that SFB can meet the rice N demand and improve the yield and NUE, and the combined application of tillering urea and SFB was better than that of single basal application with SFB.

Water-saving and drought-resistant rice (WDR) is widely grown in central China in recent years. However, studies have not explored the interaction effect of WDR and irrigation regimes on drought-resistance capacities under severe drought at sensitive growth periods. A pot experiment was conducted using a WDR cultivar Hanyou73 (HY73) and traditional high-yielding and drought-sensitive cultivar Huiliangyou 898 (HLY898). Three irrigation regimes, including flooding irrigation (W1), mild wetting-drying alternation irrigation (W2), and severe wetting-drying alternation irrigation (W3), were applied before heading. At heading, severe drought with À50 KPa soil water potential was established for all treatments and cultivars. The findings showed that cultivar HY73 under W2 treatment had the highest yield, 1000-grain yield, filled grain, relative water content, and photosynthesis potential compared with the other combinations. The higher net photosynthetic rate (P n ) was attributed to larger mesophyll conductance (g m ) in drought for cultivar HY73 under W2 treatment compared with that for cultivar HLY898 and the other water treatments. Enhanced photo-respiration rate may be an important photoprotection mechanism for achieving high P n for cultivar HY73 coupled with W2 treatment than for other combinations in drought. The relative expression level of OsPIP1;1 gene was significantly down-regulated during drought in all cultivars and water regimes. But OsPIP1;2, OsPIP2;3, OsTIP2;2, and OsTIP3;1 genes were upregulated to alleviate the significant decrease in g s and g m under drought. These results suggest that WDR and mild wetting-drying alternation irrigation (W2) have significant interaction effects in improving photosynthetic production potential by maintaining higher g m under severe drought.