为了研究软腐病的抗性基因，我们筛选出了一份易感软腐病大白菜A03、一份抗软腐病小白菜华冠以及一份抗软腐病突变体sr。本研究以感病大白菜A03与抗软腐病小白菜华冠为亲本进行杂交，获得F₂代分离群体来定位大白菜抗软腐病数量性状位点（QTLs）。利用构建的高密度遗传图谱检测到3个QTL位点，共包含166个基因。基于已有的转录组数据，在大白菜受Pc侵染的重要防御调控期，我们对这166个基因在感病大白菜A03和抗病突变体sr内的表达量进行了分析，共筛选出6个候选基因与白菜软腐病防御反应相关。其中，基因TIFY10B (JAZ2，BraA07g038660.3C) 位于A07连锁群的主效QTL位点DRQTL-3上，推测可能是白菜软腐病防御机制中起主效作用的关键基因之一。本研究为进一步研究白菜类作物中软腐病抗性机理奠定了基础。

丝束蛋白（fimbrin）是肌动蛋白细胞骨架的调节因子，参与并控制多种组织和细胞的生理生化和发育过程。然而，fimbrin在对病原菌防御中，特别是在小麦抗条锈病中的作用研究匮乏，其机制尚待阐明。本研究以小麦品种水源11（Suwon 11）与条锈菌（Puccinia striiformis f. sp. tritici，Pst）生理小种CYR23组成非亲和互作，与生理小种CYR31组成成亲和互作，利用实时荧光定量 PCR 技术（qRT-PCR）对TaFIM1基因参与小麦抗条锈病的功能进行初步分析；对在非生物胁迫和施用外源激素处理TaFIM1基因的表达特征进行分析；通过病毒诱导的基因沉默（BSMV-VIGS）技术，验证TaFIM1在小麦抗条锈病中的功能。获得以下研究结果：TaFIM1在非亲和互作中的表达量显著上调，且在48 h表达量达到峰值，是对照0 h的6.0倍；在亲和互作中，TaFIM1的表达量无明显变化。TaFIM1能够响应不同非生物胁迫，在高温（Hot）、低温（Cool）、盐（NaCl）和干旱（PEG6000）胁迫下诱导TaFIM1基因表达量上调。BSMV-VIGS试验结果显示，借助大麦条纹花叶病毒对TaFIM1基因进行诱导沉默。对沉默成功的小麦植株分别接种条锈菌CYR23和CYR31。在非亲和互作中，沉默植株的抗病性降低，叶片上出现少量的夏孢子堆；在亲和互作中，与对照相比，叶片上的夏孢子堆数量增加，沉默植株的感病性增强。组织学观察发现，在48 h和120 h，TaFIM1沉默植株叶片中菌丝分支数和菌丝长度高于对照，在120 h基因沉默植株叶片中菌落面积显著高于对照组，表明TaFIM1沉默后小麦植株与对照相比感病性增强，进一步说明TaFIM1参与植物的抗病性。因此，TaFIM1与植物抗病性相关，在小麦抵抗条锈病的侵染过程中响应正调控作用。本研究为理解fimbrin在小麦中的作用提供了新的见解。

    Covered smut, which is caused by Ustilago hordei (Pers.) Lagerh., is one of the most damaging diseases of highland barley (Hordeum vulgare Linn. var. nudum Hook. f) in Tibetan areas of China. To understand the molecular diversity of U. hordei, a total of 27 isolates, which were collected from highland barley plants from Tibet, Sichuan, Qinghai, and Gansu provinces/autonomous region, were analyzed using random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers. Among the 100 RAPD primers used, 24 primers exhibited polymorphism. A total of 111 fragments were amplified, of which 103 were polymorphic with a polymorphic rate of 92.79%. The average observed number of alleles (Na), effective number of alleles (Ne), Nei’s genetic diversity (H), Shannon’s information index (I) and polymorphism information content (PIC) value in the RAPD markers were 1.9279, 1.5016, 0.2974, 0.4503 and 0.6428, respectively. For the SSR markers, 40 of the 111 primer pairs exhibited polymorphism and provided a total of 119 bands, of which 109 were polymorphic and accounted for 91.60% of the total bands. The Na, Ne, H, I and PIC values of the SSR markers were 1.9160, 1.4639, 0.2757, 0.4211 and 0.4340, respectively. The similarity coefficients ranged from 0.4957 to 0.9261 with an average of 0.7028 among all the 27 isolates used. The dendrogram, which was developed based on the RAPD and SSR combined marker dataset showed that the 27 U. hordei isolates were divided into 3 clusters at similarity coefficient of 0.7314. We determined that RAPD and SSR markers can be successfully used to assess the genetic variation among U. hordei isolates. The RAPD markers revealed higher levels of genetic polymorphism than did the SSR markers in this study. There existed a moderate genetic difference among isolates. The molecular variation and differentiation was somewhat associated with geographical origin but not for all of the isolates.

Agriculture is facing great challenge in meeting global food security and is expected to face even greater challenge under climate change. The overall goal of this paper is to examine how finance can be used to achieve the joint objectives of development, mitigation of and adaptation to climate change in agriculture in developing world based on literature review. The results show that agriculture is much under invested and foreign aid also has not increased appropriately to assist developing countries to maintain sustainable agriculture under climate change. There are a wide range of areas in mitigation of and adaptation to climate change that need substantial investment. Major areas and successful cases mitigation of and adaptation to climate change in agriculture that have worked in developing countries are examined. A list of areas that have worked, could work and be scaled up or transferred is identified and discussed. This study concludes that mainstreaming agricultural mitigation and adaptation into agricultural development programs, enhancing local capacity, and considering different stakeholders’ needs are major experiences for successfully financing sustainable agriculture under climate change.

Under climate change, rising frequency and serious extreme weather events have challenged agricultural production. Designing appropriate adaptation measures to the extreme weather events require rigorous and empirical analysis. The overall goals of this study are to understand physical adaptation measures taken by farmers and the impacts of household and community assets on farmers’ adaptation when they face drought. The analyses are based on a unique data set collected from a household survey in three provinces in China. The survey results show that though not common on annual basis, some farmers did use physical adaptation measures to fight drought. Regression analysis reveals that both household and community assets significantly affect farmers’ adaptation behaviors. Improving households’ social capital and wealth, communities’ network and access to government’s anti-drought service can facilitate farmers’ adaptation to drought. Results indicate that community’s irrigation infrastructure and physical adaptation taken by farmers can substitute each other. Further analysis shows that the households taking adaptation measures have higher crop yields than those without taking these measures. The paper concludes with several policy implications.

The matrix metalloproteinase 23 (MMP-23), which might play a role in ovulation in mammals, was one of the promising candidate genes for litter size traits in pigs. In the present research, partial sequence of porcine MMP-23 (pMMP-23) gene, including exons 2-8 (GenBank: EU360790), was obtained. Real-time PCR analysis revealed that pMMP-23 gene was highly expressed in ovary. PCR-Sau3A I-RFLP and PCR-Acc II-RFLP assay were established to detect a C/T mutation in exon 3 (EU360790: g. 269C>T) and an A/G mutation in exon 4 (EU360790: g. 505A>G), respectively. Association study for these two SNPs with litter size was assessed in three independent populations (Minzhu, Landrace I and Landrace II). Statistical analysis demonstrated that for second and subsequent litters, TT sows produced more TNB than CC pigs in Landrace breed (P<0.05) at g. 269C>T locus, and the additive effect was significant (P<0.05); GG sows produced more TNB and NBA than AA pigs in Minzhu (P<0.01) and Landrace breeds (P<0.05) at g. 505A>G locus, and the additive effect was significant (P<0.01 or P<0.05). Our study suggested that the pMMP-23 gene might be a novel candidate gene for litter size traits, and g. 505A>G locus might be a useful molecular marker for marker assisted selection (MAS).

The carbon (C), nitrogen (N) and phosphorus (P) variations of a temperate wetland soil under continuous cultivation for 40 yr were determined and evaluated in the Sanjiang Plain, Northeast China. The results showed that the soil organic carbon (SOC) and total nitrogen (TN) contents in each soil layer decreased sharply after cultivation for 2-3 yr, and exhibited minor differences after cultivation for 11 yr, which showed an exponential decline curve with the increase of cultivation years. The reduction rates of carbon and nitrogen reserves were 14.79% and 28.53% yr-1 at the initial reclamation stages of 2-3 yr and then decreased to 2.02-3.08% yr-1 and 1.98-2.93% yr-1 after cultivation for 20 yr, respectively. Soil total phosphorus (TP) reserves decreased within cultivation for 5 yr, and then gradually restored to the initial level after cultivation for 17 yr. Both SOC and TN could be restored slightly when the farmland was left fallow for 8 yr after reclamation for 11 yr, whereas TP had no significant difference. These results demonstrated that wetland cultivation was one of the most important factors influencing on the nutrient fate and reserves in soil, which could lead to the rapid nutrient release and slow restoration through abandon cultivation, therefore protective cultivation techniques preventing nutrients from loss should be immediately established after wetland reclamation.