12个HoCP系列甘蔗种质资源初步鉴定和评价

为了解甘蔗(Saccharum spp.)亲本特性,以ROC22为对照,对12个重要Ho CP系列亲本种质进行了初步鉴定与评价。结果表明,Ho CP系列品系具有出苗率高、分蘖性好、有效茎数多、早熟高糖等特性。Ho CP01-564含糖量最高,Ho CP00-1142产量最高,Ho CP02-610发芽率和有效茎数最高,Ho CP07-613蔗糖分最高。聚类分析表明,12个Ho CP系列品系(种)可分为4类。因此,根据这些品系(种)特性可以合理配制杂交组合。     

橄榄种质资源花序表型性状遗传多样性研究

为了解橄榄[Canarium album(Loureiro)Raeuschel]花序表型性状的遗传多样性,对90份橄榄种质资源的花序性状进行观测分析。结果表明,橄榄花序的类型、支轴紧密度、着生位置和花性等表现出较丰富的多样性;从数量性状看,花序花朵数的变异系数最大,其次为支轴花朵数,变异系数最小的是花蕾直径,此外橄榄雄花花序的多样性较雌花丰富。花蕾直径与花瓣长度呈极显著正相关关系,与花序长度、花序支轴数、花序花朵数和支轴花朵数呈极显著负相关。聚类分析结果表明,橄榄种质资源的花序类型可分为3类,大部分雄花和雌花类群间差异较明显。因此,橄榄花序表型性状存在多样性和复杂性,且花序重要单一性状可能影响整体表型。     

应用多种教学方法,建设活跃的生物化学课程

生物化学授课过程中,教师通过丰富课堂资源、进行问题导向式教学、加强在线学习、建立多元化的课程考核方式及设定定时答疑制度等多种方法,激发学生学习兴趣,提升生物化学教学和学习效果,建设"笑起来""动起来"的活跃的课程。同学们普遍认为,生物化学课程内容充实有趣,教学形式多样,并且在课堂上学到了很多前沿知识。     

贵州喀斯特区C4植物物种组成与水分生态型划分

该研究通过查阅文献、核对贵州大学林学院标本库及现场群落调查与标本采集,并运用碳同位素比值法研究典型C_4植物水分利用特性,探索C_4植物在喀斯特植被恢复中的地位,进而揭示贵州喀斯特地区C_4植物资源的基本特征。结果表明:贵州喀斯特区共有C_4植物141种,隶属于74属15科,分别占全国科属种的62.50%、46.25%、24.48%,以禾本科(Gramineae)和莎草科(Cyperaceae)为主;区内C_4植物种均为一年生或多年生草本,多年生植物种略多于一年生植物种;水分生态型整体偏旱生,旱生和中生植物分别占总数的24.82%和31.21%;喀斯特区C_4植物具有高水分利用效率,但不同水分生态型间差异不显著;贵州喀斯特区C_4植物资源具有资源丰富、利用途径广泛、能长期利用、竞争力强、能大面积分布、偏旱生且水分利用幅度广的基本特征,适合喀斯特区生境,自然状态下多为恢复早期物种,有利于喀斯特区生态恢复。在贵州喀斯特恶劣生态环境下C_4植物有较好的生态适应性,并表现出较高的药用、食用、饲用、景观应用等价值,对其开发利用对贵州经济、社会发展及生态恢复有重要意义。     

药用白及资源再生策略初探

白及为兰科白及属植物。作为著名中药,白及功效多样、用途广泛,具有较高的药用价值和经济价值。随资源利用强度的增加,野生白及资源日渐萎缩,人工规模化种植是实现白及药用资源可持续利用的必由之路。优良种质及繁育技术是种植业的关键问题。为了更好地推动白及资源研究和可持续利用,本文就白及种质及快繁技术研究进展作一综述,并就白及资源再生策略进行初步探讨,为相关研究和生产提供参考。     

马铃薯种质资源的晚疫病抗性鉴定

采用离体叶片接种法,对43份马铃薯种质资源进行晚疫病抗性鉴定、比较和评价。以接种5 d后的感病品种‘Désirée’和抗病品种‘加湘1号’叶片症状为对照,鉴定出5份表现为高抗的种质资源,其中包含3个Solanum phurejia和2个S. tuberosum ssp. andigena材料。另外,还鉴定出14份中抗材料(No. 7～20)。结果表明,野生种和安第斯山栽培亚种马铃薯资源的抗性材料较为丰富,可作为晚疫病抗病育种的亲本。     

Resource conflicts and the anthropology of the dark and the good in highlands Papua New Guinea

In this article I consider why individuals sacrifice their lives for the collective. In the Porgera Valley of highlands Papua New Guinea, young men who are called ‘Rambos’ engage in sustained tribal conflicts due to increasing social inequalities in an area that is supposedly benefiting from socioeconomic development. The opening of the Porgera Gold Mine in 1990 ushered in an era of anticipated benefits that were hoped to transform the lives of the region's subsistence horticulturalists. Yet, anticipated flows of mining money and social benefits have largely failed to materialise. The abjection experienced by young men eventuated into a series of tribal fights, resulting in deaths, displacements, and the destruction of most infrastructure. I examine the fighting and its aftermath in relation to anthropologies of the dark and the good and argue that these polar opposites can hinder more subtle understandings of value plurality among Porgerans.     

Effects of soil nitrogen on diploid advantage in fireweed,Chamerion angustifolium (Onagraceae)

In many ecosystems, plant growth and reproduction are nitrogen limited. Current and predicted increases of global reactive nitrogen could alter the ecological and evolutionary trajectories of plant populations. Nitrogen is a major component of nucleic acids and cell structures, and it has been predicted that organisms with larger genomes should require more nitrogen for growth and reproduction and be more negatively affected by nitrogen scarcities than organisms with smaller genomes. In a greenhouse experiment, we tested this hypothesis by examining whether the amount of soil nitrogen supplied differentially influenced the performance (fitness, growth, and resource allocation strategies) of diploid and autotetraploid fireweed (Chamerion angustifolium). We found that soil nitrogen levels differentially impacted cytotype performance, and in general, diploids were favored under low nitrogen conditions, but this diploid advantage disappeared under nitrogen enrichment. Specifically, when nitrogen was scarce, diploids produced more seeds and allocated more biomass toward seed production relative to investment in plant biomass or total plant nitrogen than did tetraploids. As nitrogen supplied increased, such discrepancies between cytotypes disappeared. We also found that cytotype resource allocation strategies were differentially dependent on soil nitrogen, and that whereas diploids adopted resource allocation strategies that favored current season reproduction when nitrogen was limiting and future reproduction when nitrogen was more plentiful, tetraploids adopted resource allocation strategies that favored current season reproduction under nitrogen enrichment. Together these results suggest nitrogen enrichment could differentially affect cytotype performance, which could have implications for cytotypes’ ecological and evolutionary dynamics under a globally changing climate.