细胞死亡是多细胞生物生命中一种重要的生理现象。当呼吸和新陈代谢等正常功能停止时，将会发生细胞死亡。细胞死亡可分为程序性细胞死亡和非程序性细胞死亡。正常组织中发生的程序性细胞死亡，通常是维持组织机能和形态所必须的。非程序性细胞死亡则通常由非生物或生物胁迫引起。近年来，大量研究报道植物在抵御病原菌时出现了细胞死亡现象。通过分析调控植物免疫反应和细胞死亡的蛋白（PICD），发现PICD主要参与丝裂原活化蛋白激酶（MAPK）级联、活性氧（ROS）、植物激素、泛素-蛋白酶体系统、Ca²⁺信号、物质转运等六种主要的反应过程，且这些反应过程存在内在的联系。同时，PICD主要分为八类，如：含有核苷酸结合结构域和富含亮氨酸重复序列的蛋白（NLR）蛋白、受体或类受体激酶、E3泛素连接酶和其相关蛋白、ATP和GTP相关蛋白、转录因子、14-3-3蛋白和其相关蛋白、类eEF1A蛋白和丝氨酸蛋白酶抑制子，部分PICD类型具有单、双子叶植物特异性。植物细胞死亡不仅与病原相关分子模式激发的免疫反应（PTI）、效应因子激发的免疫反应（ETI）紧密相关，也与系统获得性抗性（SAR）存在重要关联。PICD在细胞外基质、细胞膜、细胞质、细胞核、线粒体、叶绿体、内质网膜、多囊泡体等众多细胞结构中均有分布，表明细胞在应对病原菌侵染和调控自身死亡时存在精妙地协同调控作用。此外，植物在抵御病原菌时的细胞死亡，通常对其自身的生长发育不利。通过筛选优异的等位变异和基因编辑等技术手段，期望达到植物免疫和生长发育间的平衡，以此增强PICD在植物应用领域中的潜力。

一方面，中国亚热带红壤区水稻土母质和肥力水平多变；另一方面，细菌多样性和群落组成在土壤生态系统过程和功能中发挥关键作用。但是水稻土的母质和肥力对细菌多样性和群落组成的影响如何仍不清楚，不同母质和肥力水平条件下驱动水稻土细菌多样性、群落组成和特异微生物种群变化的关键因素尚不明确。因此，本研究采集亚热带红壤区具有不同母质（第四纪红黏土或第三纪红砂岩）和不同肥力水平（高肥力或低肥力）的典型样地水稻土样品，通过454高通量测序测定细菌16S rRNA基因的V4−V5区，分析细菌多样性指数和群落组成变化。采用two-way ANOVA和two-way PERMANOVA探明母质和肥力对细菌多样性和群落组成的影响；主坐标分析（PCoA）、冗余分析（RDA）和多元回归树分析（MRT）明确细菌群落的变化，以及驱动该变化的关键土壤因子；共现网络分析阐明属水平特异细菌种群和关键土壤因子的关系；宏基因组差异分析工具（STAMP）确定不同土壤样品间差异物种。结果显示，母质和肥力对水稻土细菌多样性指数变化的贡献相似。但是肥力水平对细菌群落组成的影响要远大于母质。土壤因子，特别是土壤质地与细菌多样性指数密切相关。RDA分析发现土壤有机碳（SOC）是影响细菌群落组成的首要因素，并且25.5 g kg⁻¹有机碳含量是驱动高肥力和低肥力土壤细菌群落组成分异的关键阈值。共现网络分析暗示高肥力水平下，由于土壤环境的改善，细菌趋向于合作关系，并且富营养型细菌占主导地位。STAMP分析发现高肥力水稻土中Massilia和Rhodanobacter等富营养型细菌大量富集；而低肥力土壤中Anaerolinea等贫营养型细菌占主导。研究结果表明，不同母质和肥力水稻土中，土壤质地影响细菌多样性指数变化；而养分水平，特别是有机碳水平决定细菌群落组成的变化。

The optimized nitrogen fertilization location differs in different rice-growing regions.  We optimized nitrogen deep-point application in root-growing zone (NARZ) for transplanted rice in subtropical China.  Field plot experiments were conducted over two years (2014–2015) in a double-rice cropping system to evaluate the effects of nitrogen (N) fertilizer location on grain yield and N use efficiency (NUE).  Four different nitrogen deep-point application methods (DN) were compared with traditional broadcast application (BN) using granular urea.  The results showed that grain yield,  recovery efficiency of N (RE_N), agronomic efficiency of N (AE_N), and partial factor productivity of N (PFP_N) significantly increased 10.3–63.4, 13.7–56.7, 24.7–201.9 and 10.2–63.4%, respectively, in DN treatment compared to BN, respectively.  We also find that DN treatments increased grain yield as well as grain N content, and thus grain quality, in comparison with conventional BN treatment.  Correlation analysis indicated that significant improvement in grain yield and NUE mainly resulted from increases in productive panicle number and grain N content.  In our proposed NARZ method, granular urea should be placed 0 to 5 cm around the rice seeding at a 12-cm depth druing rice transplanting.  In NARZ, balanced application of N, P and K further improved grain yield and NUE over treatments with a single N deep-point application.  High N uptake by the rice plant did not cause significant soil fertility depletion, demonstrating that this method could guarantee sustainable rice production.    
 

The Hina gene is one of the two known Hin genes for hardness, and its RNA expression is correlated with grain hardnessand dry matter digestibility variation. In this study, only one clone of Hina gene was obtained from one barley accession.A total of 121 Hina gene sequences were isolated from 121 wild barley (Hordeum spontaneum) accessions in Israel, Iran,and Turkey, and then their molecular characteristics were compared with 97 Hina gene sequences from 74 cultivatedbarley (H. vulgare) lines in Europe and 23 landrace (H. vulgare) with global distribution and other 26 Hina gene sequencesfrom cultivated barleys (H. vulgare) with unknown global distribution. Cis-acting regulatory element (CARE) searchingrevealed that there were different types of regulatory element for the Hina gene in wild and landrace/cultivated barleys.There were six consistent cis-acting binding sites in wild and landrace/cultivated barleys, whereas 8 to 16 inconsistentTATA-boxes were observed. In addition, three special elements (E2Fb, Sp1, and boxS) were only observed in wild barley,while one (AT1-motif) was only found in landrace/cultivated barley. Forty-four deduced amino acid sequences of HINAfrom wild and landrace/cultivated barleys were obtained by deleting repetitive amino acid sequences, and they wereclustered into two groups on the basis of Neighbor-Joining analysis. However, there was no obvious difference in theamino acid sequences of HINA between wild and landrace/cultivated barleys. Comparing to protein secondary structureof wheat PINA, it was indicated that HINA also existed a signal peptide. In addition, HINA was a hydrophilic protein onthe basis of the protein properties and composition.