世界范围内有各种品种、类型的鸡，它们的品种特征各不相同，是宝贵的遗传资源。目前，对影响这些鸡品种的特异性表型的遗传决定因素的研究还有待进一步加深。深入了解品种特异性表型变异的潜在遗传机制可以帮助育种者培育和改良鸡品种。本研究对7个来自山东省的本地品种共140只鸡和20只引进的隐性白羽鸡的全基因组进行了重测序。基于常染色体单核苷酸多态性(SNPs)的群体基因组比较结果揭示了鸡群基于地理距离的聚类模式。通过全基因组范围内的选择性清除分析，本研究确定了甲状腺刺激激素受体(TSHR，繁殖性状，生理节律)，红细胞膜蛋白带4.1 样 1 (EPB41L1，体型大小)和烷基甘油单加氧酶(AGMO，攻击行为)是主要候选的鸡品种特异性决定基因。此外，本研究利用机器学习分类模型，基于与品种特征显著相关的SNPs对鸡的品种进行判别，预测准确率为92%，可有效实现莱芜黑鸡的品种鉴定。本研究首次提供了山东地方鸡种的完整基因组数据，相关的分析揭示了山东地方鸡种的地理模式和鸡的品种特异性性状相关的潜在的候选基因。此外，本研究开发了一个基于机器学习的预测模型，使用SNPs数据进行品种判别，该部分内容为利用机器学习方法开发品种分子身份证提供了参考。本研究揭示的地方鸡品种遗传基础有助于更好地理解鸡资源特性的内在机制。

 

近几十年来，保护性农业（conservation agriculture，CA）因其有利于农业可持续性发展而获得广泛推广，但其对田间生物多样性和作物生产力的综合影响尚不清楚。本研究通过调查传统耕作（conventional tillage，CT），免耕（no tillage，NT）和少耕（reduced tillage，RT）三种耕作方式下稻田生物多样性和病、虫、草害等指标发现，降低耕作强度能显著降低稻田虫害、病害和杂草的发生，同时增加田间捕食性天敌数量，进而提高水稻产量。连续两年的调查结果显示，在CT模式下稻田主要害虫如稻飞虱和福寿螺发生量分别为74.78和9.91 m^-2，而在RT模式分别为14.69和5.16 m^-2，发生量显著降低，并且在RT模式下病害发生率和杂草密度也均有明显下降。同时，实施RT的稻田水稻产量（7477.01 kg ha^-1）相比于CT（6489.19 kg ha^-1）增加15.22%。此外，在CT模式下稻田害虫捕食性天敌的平均密度为11.22 m^-2，而RT和NT模式下分别为19.73和20.48，虫口数显著增加，同时丰富度也显著增加，说明CA对促进农业生态系统生物多样性有重要作用。综上所述，实施RT有利于水稻病虫草害防治，提高水稻产量和农业生态系统可持续性。

草地贪夜蛾于2018年12月中旬入侵中国西南地区后，已对国家农业生产构成了重大威胁。秦岭-淮河一线是中国南北气候过渡带，也是玉米和小麦的主产区。本研究基于2019年草地贪夜蛾在该地区的发生特点，利用日平均地面气温和925百帕的夜间风场数据，采用顺推轨迹分析方法模拟了秦岭-淮河地区虫源的发生和迁出路径。研究结果表明该地区羽化成虫的迁飞活动始于6月下旬，受复杂的地形地貌的影响，秦岭山区草地贪夜蛾在9月中旬之前以北迁为主，宁夏和内蒙古自治区是其主要迁入地；在地势平坦的淮河流域，草地贪夜蛾8月中旬之前主要随季风向北迁移，华北平原是主降区但可能波及到东北平原，8月中旬开始向南回迁至长江流域。本研究预测了秦岭-淮河地区草地贪夜蛾种群随季风的迁出路径，为区域性监测预警和综合防治提供了理论依据。

Lipoxygenases (LOXs) are a group of non-heme, iron-containing enzymes and extensively involved in plant growth and development, ripening and senescence, stress responses, biosynthesis of regulatory molecules and defense reaction. In our previous study, 18 LOXs in melon genome were screened and identified, and five 13-LOX genes (CmLOX08, CmLOX10, CmLOX12, CmLOX13 and CmLOX18) were predicted to locate in chloroplast. Phylogenetic analysis result showed that the five genes have high homology with jasmonic acid (JA) biosynthesis-related LOXs from other plants. In addition, promoter analysis revealed that motifs of the five genes participate in gene expression regulated by hormones and stresses. Therefore, we analyzed the expressions of the five genes and LOX activity in leaves of four-leaf stage seedlings of oriental melon cultivar Yumeiren under abiotic stress: wounding, cold, high temperature and hydrogen peroxide (H2O2), and signal molecule treatments: methyl jasmonate (MeJA), abscisic acid (ABA) and salicylic acid (SA). Real time qPCR revealed that wounding and H2O2 induced the expressions of all the five genes. Only CmLOX08 was induced by cold while only CmLOX13 was suppressed by high temperature. ABA induced the expressions of CmLOX10 and CmLOX12 while inhibited CmLOX13 and CmLOX18. MeJA increased the 3 genes expressions except CmLOX08 and CmLOX13, whereas SA decreased the effect, apart from CmLOX12. All the abiotic stresses and signal molecules treatments increased the LOX activity in leaves of oriental melon. In summary, the results suggest that the five genes have diverse functions in abiotic stress and hormone responses, and might participate in defense response. The data generated in this study will be helpful in subcellular localization and transgenic experiment to understand their precise roles in plant defense response.

  The safety of feeding transgenic cry1Ab/cry1Ac rice (a genetically modified (GM) rice variety) to broilers was examined from an immunological perspective. Hatchling Arbor Acres chickens (240) were assigned to two dietary treatments (diets containing GM or non-GM rice) with 12 replicates per group and 10 birds per replicate. Traits were measured on one randomly selected bird from each replicate at d 21 and 42. The 42-d feeding trial revealed that cry1Ab/cry1Ac rice had no significant effect relative to non-GM rice on body weight and the immune organ indices. No significant pathological lesion in the spleen and bursa of Fabricius was found in the GM rice group. There were no significant differences in serum concentrations of immunoglobulin Y (IgY), IgM, interleukin 4 (IL-4) and IL-6 between the two groups at d 21 or 42, except for IL-6 being higher (P<0.05) in the GM-fed chickens at d 42. There were no differences in the T and B lymphocyte transformation rate and CD4+/CD8+ ratio between the two groups at d 42. Additionally, there was no significant difference between the two diets in expression of relevant genes viz. the major histocompatibility complex class II beta chain (BLB2), interferon beta 1 (IFNβ), tumour necrosis factor alpha-like (TNFα) and toll-like receptor 4 (TLR4) in the spleen and bursa of Fabricius. All the data demonstrated that transgenic cry1Ab/cry1Ac rice had no adverse effect on these aspects of immune function of broilers during 42-d feeding trial. Transgenic rice was therefore indistinguishable from non-GM rice in terms of short-term feeding in chickens.  

Potato late blight, caused by the oomycete pathogen Phytophthora infestans, is the most serious disease of potato worldwide. The adoption of varieties with resistance genes, especially broad-spectrum resistance genes, is the most efficient approach to control late blight. Solanum demissum is a well-known wild potato species from which 11 race-specific resistance genes have been identified, however, no broad-spectrum resistance genes like RB have been reported in this species. Here, we report a novel reisistance locus from S. demissum that potentially confer broad-spectrum resistance to late blight. A small segregating population of S. demissum were assessed for resistance to aggressive P. infestans isolates (race 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11). This coupled with nucleotide binding site (NBS) profiling analyses, led to the identification of three fragments that linked to the potential candidate resistance gene(s). Cloning and sequence analysis of these fragments suggested that the identified resistance gene locus is located in the region containing R2 resistance gene at chromosome 4. Based on the sequences of the cloned fragments, a co-segregating sequence characterized amplified region (SCAR) marker, RDSP, was developed. The newly identified marker RDSP will be useful for marker assisted breeding and further cloning of this potential resistance gene locus.

A comparative slaughter trial and a metabolism trial were conducted to determine the requirement of net energy (NE) and metabolizable energy (ME) by the crossbreed of German Mutton Merino×Inner Mongolia Merino for fattening from 35 to 50 kg of body weight (BW). 49 crossbred female lambs ((33.9±2.3) (SD) kg BW) of German Mutton Merino×Inner Mongolia Merino were used. 34 lambs were randomly chosen for comparative slaughter, which were offered an identical mixture diet (concentrate:roughage=55:45) at 100, 75 or 55% of ad libitum intake, whereas the remainders were used in the metabolism trial to evaluate the ME of the diet after methane production was measured by open-circuit respirometry. As feed intake decreased from 100 to 75 and 55% of ad libitum intake, the apparent digestibility of dry matter (DM) linearly increased (P=0.010) from 60.8 to 63.6 and 66.9%, respectively, and methane production decreased from 52.1 to 44.3 and 39.9 L d-1, respectively, but the ratio of methane energy to gross energy intake increased linearly (P=0.010) from 8.20 to 8.96 and 10.97%, respectively. Consequently, the ME values of the diet increased from 9.35 to 9.64 and 9.85 MJ kg-1 DM, respectively. The NE requirement for maintenance (NEm) was 255 kJ kg-1 BW0.75, and the ME requirement for maintenance (MEm) was 352 kJ kg-1 BW0.75, with a partial energy efficiency for maintenance (km) of 0.72. The NE requirement for growth (NEg) ranged from 1.26 to 4.66 MJ d-1 as average daily gains increased from 100 to 300 g d-1, with a partial energy efficiency for growth (kg) of 0.45. These results indicated that the NEg required by crossbred female lambs of German Mutton Merino×Inner Mongolia Merino was lower than the recommendation of the American or British nutritional system.

In previous experiment, we isolated a compound dibutyl phthalate (DBP) from Vaccaria segetalis which had galactopoieticfunction on mammary gland epithelial cells of dairy cow (DCMECs). In this experiment, we ascertained the metabolicregulation function of DBP on DCMECs. Many genes related to lactation including Stat5, AMPK, â-casein, Glut1, SREBP-1,PEPCK, and ACC were detected by real-time PCR. Furthermore, Stat5 and AMPK were detected by Western blot andimmunofluorescence co-localization, respectively. The results showed that DBP stimulates the expression of Stat5 andp-Stat5, thus activates Stat5 cell signal transduction pathway and stimulates â-casein synthesis. DBP also raises theactivities of Glut1 and AMPK to stimulate glucose uptake and glycometabolism and activates the expression of AMPKdownstream target genes PEPCK and ACC and expression of SREBP-1 to stimulate milk fat synthesis. In addition, theactivities of HK, G-6-PDH, ICDH, ATPase, and energy charges were stimulated by DBP to increase the energy metabolismlevel of DCMECs. The results showed DBP stimulates energy metabolism related to galactopoietic function in DCMECs.