Origin of and resulting floristic composition from seedbanks in agroforestry systems of Tomé‐Açu,Eastern Amazon

The objective of this study was to verify the origin of and resulting floristic composition from seedbanks in different agroforestry systems in Tomé‐Açu, Brazil. The seedbanks were sampled in three smallholder farmers (Demonstration Units = DU), each with three agroforestry treatments and secondary forest as control. Seedling emergence in a glasshouse was used to quantify and identify the seeds collected in 2008. The floristic composition of the above‐ground community was characterised with annual floristic surveys from 2008 to 2011. The total densities and diversity of the seedbanks were not different among the treatments within a given DU, but differences occurred among DU. The most abundant woody species had higher seed densities in the secondary forests than in DU. Conversely, among the herbaceous species, two groups were differentiated: species with similar densities between the DU and the secondary forest and species with higher density in the DU. In the DU, the similarity between the floristic composition of the seedbank and the flora surveyed in 2008 was high, but decreased in subsequent years. The species present in the seedbank of agroforestry systems are highly influenced by the secondary forest, but provide little information about the floristic composition that will arise in the future.     

3,4,5-三羟基苯甲酸甲酯防治番茄青枯病的物理作用方式及其对番茄根系次生代谢物质的影响

通过生物学方法测定3,4,5-三羟基苯甲酸甲酯(MG)防治番茄青枯病的物理作用方式,采用气相色谱-质谱联用方法分析该化合物对番茄根系组织次生代谢物质的影响。结果表明,3,4,5-三羟基苯甲酸甲酯对番茄青枯病有较好的预防作用,持效期较长,施药15d后接种青枯病菌,防效仍达52.12%;该化合物可快速扩散到番茄根系组织内,但其向植株顶部和基部的输导作用弱,对番茄青枯病的治疗效果差。番茄根系中共鉴定出36种次生代谢物质,与对照相比,3,4,5-三羟基苯甲酸甲酯处理对番茄根系次生代谢产物的组成和相对含量有明显影响,其中与抑菌活性相关的物质有香叶醇、豆甾醇、β-谷甾醇和木栓醇等4种,前3种物质在3,4,5-三羟基苯甲酸甲酯处理植株体内表现为含量显著升高,木栓醇则为苗期用3,4,5-三羟基苯甲酸甲酯处理后番茄根系新增的化合物。     

院系二级管理模式下高职专业建设主体角色探析

高校的功能在于人才培养、科学研究、服务社会和文化传承,而高职院校更加侧重人才培养,其核心竞争力的最终体现是其产出（技能型专业技术人才）的岗位适应性,通过专业建设持续提升人才培养质量是构筑核心竞争力的根本途径。立足于当前高职院校普遍采用的二级管理模式,从专业建设的内在逻辑出发,分析高职院校各专业建设主体的角色分工及协作关系。     

多倍体育种对植物次生代谢影响的研究

多倍体育种是提高植物次生代谢产物产量的手段之一。从次生代谢产物、次生代谢途径及其基因调控方面综述了近年来国内外研究人员关于多倍体育种对植物次生代谢产生影响的研究进展,探讨了在研究过程中尚需解决的问题,并展望了多倍体育种的研究前景。     

植物内生放线菌及其作为微生物农药开发的潜力

植物内生放线菌广泛存在于各种植物中,具有丰富的多样性。许多植物内生放线菌具有杀虫、杀菌及除草活性。一些植物内生放线菌还具有促进植物生长的活性。植物内生放线菌还产生结构多样的具有农药活性的次生代谢产物。植物内生放线菌具有开发成为微生物农药的潜力,其代谢产物可望为新农药的创制提供先导结构。     

应用电子档案袋进行中职数学课堂评价初探

随着信息技术的普及和智能化校园的推进,中职数学教学与信息技术的整合迎来新契机,本文利用电子档案袋来促进中职数学课堂教学评价,并以之来促进教师对教学设计的完善,提高学生参与度,期待为推动中职数学的课堂教学改革提供有益的尝试。     

渤海湾天津近岸海域大型底栖动物群落结构及次级生产力的初步研究

为了解渤海湾天津近岸海域大型底栖动物现状,于2014年5月和8月分两个航次对该海域14个站位大型底栖动物栖息密度、生物量和生物多样性进行调查,同时用Brey(1990年)经验公式计算年次级生产力(P)以及年次级生产力与年生物量(B)的比值(P/B)。结果表明:渤海湾天津近岸海域大型底栖动物隶属7门9纲29种,包括软体动物、节肢动物、多毛类、棘皮动物和其他底栖动物;年平均栖息密度为56.07 ind./m~2,年平均生物量(湿质量)为52.98 g/m~2,Shannon-Weiner多样性指数平均为1.64,Margalef物种丰富度指数平均为0.59,Pielou均匀度指数平均为0.88,年平均生物量为9.54 g/m~2(去灰分干质量),年平均次级生产力为6.12 g/(m~2·a)(去灰分干质量),P/B值平均为0.70 a~(-1)。研究表明:本调查海域的次级生产力与整个渤海湾相近,高于南黄海和东海,低于海坛海峡和胶州湾;P/B值较其他海域偏低,说明渤海湾近岸海域大型底栖动物群落中,生活史短、代谢快的小型种类所占比例低于其他海区;整个渤海湾天津近岸海域(63 km~2)大型底栖动物年次级生产力约为386 t(去灰分干质量),或是2144 t(鲜质量)。     

Relationship between the number of tapping-induced secondary laticifer lines and rubber yield among Hevea germplasm

The lack of suitable early selection parameters means that traditional rubber breeding for yield is time-consuming and inefficient. Laticifer is a tissue specific for natural rubber biosynthesis and storage in rubber tree. The number of the secondary laticifers in the trunk bark tissues is positively correlated with rubber yield in the matured rubber trees that are regularly tapped. In the present study, the rubber yield from 280 of 4–5 year-old virgin trees from 7 cross combinations was compared with the number of newly differentiated secondary laticifers caused by tapping. Results showed that the number of tapping-induced lines of secondary laticifers varied in different germplasm and was positively related to the rubber yield, indicating this could be used as a suitable parameter for early evaluation of yield potential of rubber trees.     

Silages containing bioactive forage legumes: a promising protein‐rich feed source for growing lambs

Forage legumes that contain secondary compounds are considered to be less susceptible to proteolysis than other legumes, with improved silage quality and possibly improved animal performance. This was investigated feeding five groups of growing lambs for 10 weeks, five silages composed of pure timothy (T; Phleum pratense), mixtures of T with red clover (Trifolium pratense; T‐RC, 50/50 on DM basis), sainfoin (Onobrychis viciifolia; T‐SF), or both (T‐RC‐SF, 50/25/25), or a mixture of the two legumes (RC‐SF). Including SF and/or RC in silages improved silage fermentation as shown by higher lactic acid and lower soluble N and NH₃ contents than in T silage. Voluntary intakes were higher with all the RC‐containing silages than with T and T‐SF. The T‐SF silage had the lowest, and RC‐containing silages the highest average values for daily gain, feed conversion efficiency, live weight and carcass weight. The differing effects of these silages cannot be totally explained by differences in their nutritive value and so may be due to their bioactive compounds impacting differently on feeding motivation and digestive efficiency. These results suggest that including RC in silages is a promising strategy to combine improved animal performance with reduced environmental pressure.     

南方早熟梨二次开花的成因及防治研究进展

南方早熟梨二次开花常导致翌年挂果率低、小果率增多,影响产量和经济效益,是目前生产上面临的主要问题之一。研究证实,气候条件、栽培管理措施、品种生理特性是引起南方早熟梨二次开花的主要原因。通过选择适宜品种、加强病虫害防治、合理肥水供应、科学整形修剪及调控挂果量,可有效防治南方早熟梨二次开花。对于已二次开花的梨树,可采取加强营养供给、及时剪除已抽生花枝的枝梢、内接花芽等措施,以更新树体、恢复树势,提高坐果率和产量。加强抗性品种选育,在坚持＂预防为主,综合防治＂原则的基础上,强化植物激素、酶学及分子生物学研究,是未来研究工作的重点。