根结线虫病是农业生产上的毁灭性病害，每年造成巨大的经济损失。南方根结线虫是一种寄生范围广、危害严重、防治困难的根结线虫，其防治主要依赖化学农药，不仅污染环境、危害人类健康，而且大大增加线虫的抗药性。解析根结线虫的致害分子机制，对于制定环保、经济、高效的防治策略具有重要研究价值。研究发现，根结线虫在寄生过程由食道腺表达、通过口针分泌出许多效应子，在线虫侵染和寄生阶段发挥重要作用。不同种类效应子与寄主植物之间产生错综复杂的相互作用，功能机制有待深入解析。在本研究中，我们鉴定了一种新的南方根结线虫效应子Minc03329，对氨基酸序列分析发现，其包含用于分泌的信号肽序列和一个C型凝集素结构域。酵母信号序列捕获实验表明Minc03329的信号肽是有功能的，具有分泌功能；原位杂交实验结果表明Minc03329在南方根结线虫亚腹食道腺中特异表达；实时荧光定量PCR结果证实 Minc03329 在线虫寄生初期表达量显著升高；病毒介导的基因沉默干扰线虫 Minc03329 表达，显著降低了南方根结线虫的致病性；相反，Minc03329转基因拟南芥接种南方根结线虫后根结数和卵块数显著增加，表明效应子Minc03329在植物细胞中表达，可以显著增加植物对南方根结线虫的敏感性；Minc03329 在本氏烟草叶片细胞中瞬时表达能抑制由小鼠促凋亡蛋白BAX引发的细胞程序性死亡；通过对Minc03329转基因拟南芥和野生型拟南芥进行转录组数据比较分析，发现Minc03329转基因拟南芥中许多防御相关基因表达显着下调；此外，一些差异表达基因可能参与了南方根结线虫摄食位点的形成，但是其分子机制有待深入解析。本研究是在揭示凝集素效应子MiCTL1功能机制后，解析的第二个南方根结线虫凝集素类效应子的功能。验证了凝集素类效应子在线虫与植物互作过程通过抑制植物免疫反应，帮助线虫寄生的分子机制。研究结果为揭示根结线虫致病分子机理，以及根结线虫防治分子靶标利用提供了重要理论依据。

研究西北地区（西宁、武威）玉米间作豆科绿肥系统中豆科绿肥的生物固氮量及其向玉米的氮素转移量，探讨间作条件下玉米利用豆科绿肥生物固氮的可能性。试验处理包括玉米单作、绿肥（箭筈豌豆和毛叶苕子）单作、玉米和绿肥间作。与绿肥单作相比，间作绿肥的生物固氮效率无显著变化（西宁毛叶苕子除外）；但西宁、武威两地箭筈豌豆生物固氮量分别从1.16和1.10 g/盆显著降低至0.77和0.55 g/盆，西宁毛叶苕子生物固氮量从1.02 g/盆显著降低至0.48 g/盆。西宁和武威间作系统中，箭筈豌豆氮素转移量分别为21.54和26.81 mg/盆，占玉米吸氮量的32.9和5.9%；毛叶苕子的氮素转移量分别为39.61和46.22 mg/盆，占玉米吸氮量的37.0和23.3%。路径分析结果表明，绿肥生物固氮量主要与土壤养分与地上部干物质量相关，氮素转移量主要与土壤δ¹⁵N相关。结果表明，玉米吸氮量的5.9～37.0%来自于豆科绿肥生物固氮，毛叶苕子的氮素转移量高于箭筈豌豆。综上所述，与豆科绿肥间作，是玉米有效利用豆科绿肥生物固氮的可能途径。

Synthetic hexaploid wheat (SHW), possesses numerous genes for drought that can help breeding for drought-tolerant wheat varieties.  We evaluated 10 root traits at seedling stage in 111 F₉ recombinant inbred lines derived from a F₂ population of a SHW line (SHW-L1) and a common wheat line, under normal (NC) and polyethylene glycol-simulated drought stress conditions (DC).  We mapped quantitative trait loci (QTLs) for root traits using an enriched high-density genetic map containing 120 370 single nucleotide polymorphisms (SNPs), 733 diversity arrays technology markers (DArT) and 119 simple sequence repeats (SSRs).  With four replicates per treatment, we identified 19 QTLs for root traits under NC and DC, and 12 of them could be consistently detected with three or four replicates.  Two novel QTLs for root fresh weight and root diameter under NC explained 9 and 15.7% of the phenotypic variation respectively, and six novel QTLs for root fresh weight, the ratio of root water loss, total root surface area, number of root tips, and number of root forks under DC explained 8.5–14% of the phenotypic variation.  Here seven of eight novel QTLs could be consistently detected with more than three replicates.  Results provide essential information for fine-mapping QTLs related to drought tolerance that will facilitate breeding drought-tolerant wheat cultivars.

Based on the sequence of a novel expressed sequence tag (EST), the full-length cDNA of 1 017 nucleotides was cloned from Brassica napus cv. Xiangyou 15 through rapid amplification of cDNA ends (RACE). The gene was designated as Bnhol34 (HQ585980), encoding a protein of 338 amino acids. BLAST analysis showed no high degree of sequence identity to any known gene. The calculated molecular weight of the Bnhol34 protein was 36.23 kDa, and the theoretical isoelectric point was 8.74. The Bnhol34 was also cloned from a high oleic acid mutant 854-1 through homologous cloning. There was no difference between the two Bnhol34 genes. Bnhol34 was localized in a tissue-specific manner in B. napus, and its expression level was about eight-fold greater in Xiangyou 15 seeds than in 854-1. The promoter region sequences of Bnhol34 were then isolated from Xiangyou 15 and 854-1, and a 93-bp deletion was found to occur in the Bnhol34 promoter region of 854-1. Three abscisic acid-responsive cis-elements (ABRE) were identified in the promoter region of Xiangyou 15. Real-time PCR analyses revealed that exogenous abscisic acid increased Bnhol34 expression by about four-fold in Xiangyou 15 seeds, yet did not change Bnhol34 expression in 854-1. It appeared that Bnhol34 might be abscisic acid insensitive in 854-1.

Our previous studies demonstrated that the region around markers BMS470 and BMS1242 on BTA6 showed a linkage to 305-d milk yield and composition traits in the Chinese Holstein population. We herein focused on such narrow region to fine map milk production QTLs with 15 SNPs across 25 Mb with each SNP in 1 Mb within most regions in a Chinese Holstein population with daughter design. 1 449 Holstein cows and 11 sires were genotyped for such SNPs by using TaqMan probe and RFLP assays. Multipoint linkage analysis across family revealed a QTL affecting milk yield between PPARGC1A C4075T and SLC34A2 T1713C. Meanwhile, within family analysis found three milk yield QTLs (two in CR T60984131G-CEP135 C501T and one in PDLIM5 A106C-OPN T3907, a fat yield QTL in UGDH T1670C-CR T60984131G region, and two protein yield QTLs in TBC1D1 G501C-UGDH T1670C and PPARGC1A C4075T-SLC34A2 T1713C, respectively. Associations between aforementioned significant SNP markers and milk production traits were further implemented. We found significant associations of PPARGC1A C4075T, SLC34A2 T1713C with milk yield (P<0.05, P<0.01, P<0.01), UGDH T1670C, and CR T60984131G with fat yield (P<0.01, P<0.01), and PPARGC1A C4075T, SLC34A2 T1713C, UGDH T1670C and OPN T3907 with protein yield (P<0.01, P<0.01, P<0.01, P<0.01). Our findings implied that QTLs affecting milk production traits on BTA6 were pleictropism or multigenic effect and PPARGC1A and OPN may be the causal mutations behind milk production QTLs on BTA6 in the Chinese Holstein population.

To understand genetic structure and diversity of parental cultivars involved in China Mainland sugarcane breeding programs, 92 elite parents and 4 wild relatives were genotyped with 18 microsatellite DNA markers. The genetic similarity (GS) values among the cultivars ranged from 0.346 to 0.960 with an average of 0.533. Among the introduced cultivars, India accessions had the closest genetic distance to China Mainland accessions (0.447), while Australia accessions have the furthest distance (0.503). A comparison of allelic diversity among geographical origins showed that there were 22 China Mainland specific alleles, of which 28% were derived from native S. spontaneaum germplasm in China. Model-based genetic structure, clustering, and principal components analyses consistently revealed there were five groups within the 96 accessions. Groups 1, 2, 4, and 5 consisted of all cultivars and group 3 only contained wild germplasm. Group 2 was characterized as the Introduction group with 46 cultivars predominantly introduced from Australia, Taiwan of China, India, and USA. Groups 1, 4, and 5 consisted of cultivars mostly originated from China Mainland, defined as the Complex group, Yacheng lines group, and F134/CP72-1210 group, respectively, upon their pedigree. By understanding the genetic relationships among the parental cultivars, breeders can gain a rational basis for expanding the gene pool and select the best parental accessions for crossing.