甜瓜株型性状的遗传分析

为了明确了甜瓜(Cucumis melo L.)主要株型性状的遗传模型与基因的作用方式,并估测了主基因遗传效应与遗传力,本研究以网纹甜瓜RE-19(Cucumis melo var.cantalupensis Naudin)和哈密瓜AM-5(Cucumis melo var.ameri Pangalo)为亲本,构建4世代群体(P1、P2、F1和F2),对甜瓜4个株型性状采用植物数量性状主基因+多基因混合遗传模型分析法进行了遗传分析。结果表明,节间长和侧枝长遗传符合E-2模型,即两对加性-显性主基因+加性-显性多基因模型,主茎直径遗传符合E-1模型,即两对加性-显性-上位性主基因+加性-显性多基因遗传模型,叶面积遗传符合C-0模型,即加性-显性-上位性多基因遗传模型。节间长、侧枝长和主茎直径的主基因遗传率分别为75.03%、54.86%和42.83%。节间长、侧枝长、主茎直径和叶面积的多基因遗传率分别为2.68%、6.41%、2.1%和55.47%。4个性状遗传变异平均值分别占其表型变异的77.68%、61.06%、50.25%和55.47%,表明甜瓜株型相关的4个性状主要受遗传因子控制,且甜瓜节间长与侧枝长主基因遗传力较高,主茎直径主基因遗传力较低,而叶面积受多基因控制,无主效基因。因此,在甜瓜株型育种中,在早期世代进行节间长与侧枝长的选择是有效的,而对主茎直径和叶面积的选择,宜在高代进行选择。本研究为甜瓜的株型改良育种提供了理论基础。     

土壤与植物中的硫素营养研究进展

综述了土壤与植物硫素营养的近期研究进展,包括土壤中硫的转化;植物体中硫酸盐的吸收途径;植物的缺硫症状;硫素对植物生理功能的影响;硫与植物其他营养元素的互作关系等。以期为硫素研究提供参考。     

沼液施用对土壤与植物中磷分布的影响

以余杭青菜地潮土、红壤为例,选取未施加沼液、正常施加沼液以及加倍施加的土壤剖面各3条,研究沼液施加对土壤和植物磷(P)分布的影响,为畜禽废弃物资源化利用和瓜果合理施肥提供科学依据。结果表明:(1)沼液施加能够提高表层土壤的总P含量,而对深层土壤的总P含量影响不大;(2)沼液施加后,土壤中的Fe-P含量会有显著增加;(3)青菜茎和叶中的总P含量随沼液施加量的增加而增加,其中叶增加的趋势最明显。     

Fungal and bacterial N2O production regulated by soil amendments of simple and complex substrates

Fungal N₂O production results from a respiratory denitrification that reduces NO₃⁻/NO₂⁻ in response to the oxidation of an electron donor, often organic C. Despite similar heterotrophic nature, fungal denitrifiers may differ from bacterial ones in exploiting diverse resources. We hypothesized that complex C compounds and substances could favor the growth of fungi over bacteria, and thereby leading to fungal dominance for soil N₂O emissions. Effects of substrate quality on fungal and bacterial N₂O production were, therefore, examined in a 44-d incubation after soils were amended with four different substrates, i.e., glucose, cellulose, winter pea, and switchgrass at 2 mg C g⁻¹ soil. During periodic measurements of soil N₂O fluxes at 80% soil water-filled pore space and with the supply of KNO₃, substrate treatments were further subjected to four antibiotic treatments, i.e., no antibiotics or soil addition of streptomycin, cycloheximide or both so that fungal and bacterial N₂O production could be separated. Up to d 8 when antibiotic inhibition on substrate-induced microbial activity and/or growth was still detectable, bacterial N₂O production was generally greater in glucose- than in cellulose-amended soils and also in winter pea- than in switchgrass-amended soils. In contrast, fungal N₂O production was more enhanced in soils amended with cellulose than with glucose. Therefore, fungal-to-bacterial contribution ratios were greater in complex than in simple C substrates. These ratios were positively correlated with fungal-to-bacterial activity ratios, i.e., CO₂ production ratios, suggesting that substrate-associated fungal or bacterial preferential activity and/or growth might be the cause. Considering substrate depletion over time and thereby becoming limited for microbial N₂O production, measurements of soil N₂O fluxes were also carried out with additional supply of glucose, irrespective of different substrate treatments. This measurement condition might lead to potentially high rates of fungal and bacterial N₂O production. As expected, bacterial N₂O production was greater with added glucose than with added cellulose on d 4 and d 8. However, this pattern was broken on d 28, with bacterial N₂O production lower with added glucose than with added cellulose. In contrast, plant residue impacts on soil N₂O fluxes were consistent over 44-d, with greater bacterial contribution, lower fungal contribution, and thus lower fungal-to-bacterial contribution ratios in winter pea- than in switchgrass-amended soils. Real-time PCR analysis also demonstrated that the ratios of 16S rDNA to ITS and the copy numbers of bacterial denitrifying genes were greater in winter pea- than in switchgrass-amended soils. Despite some inconsistency found on the impacts of cellulose versus glucose on fungal and bacterial leading roles for N₂O production, the results generally supported the working hypothesis that complex substrates promoted fungal dominance for soil N₂O emissions.     

10%氰氟草酯水乳剂防除水稻移栽田禾本科杂草效果研究

以新型环境友好型的新制剂10%氰氟草酯水乳剂为供试药剂,于2013年在我国具有代表性的5个水稻主产区进行了水稻田除草药效试验。结果表明,10%氰氟草酯水乳剂对水稻田禾本科杂草具有良好的防除效果且对水稻生长安全,推荐使用制剂用药量为50～70mL/667m2（有效成分75～100g ai/hm2）。     

Plant–soil interactions in metal contaminated soils

The legacy of industrialization has left many soils contaminated. However, soil organisms and plant communities can thrive in spite of metal contamination and, in some cases, metabolize and help in remediation. The responses of plants and soil organisms to contamination are mutually dependent and dynamic. Plant–soil feedbacks are central to the development of any terrestrial community; they are ongoing in both contaminated and healthy soils. However, the theory that governs plant–soil feedbacks in healthy soils needs to be studied in contaminated soils. In healthy soils, negative feedbacks (i.e. pathogens) play a central role in shaping plant community structure. However to our knowledge, the nature of feedback relationships has never been addressed in contaminated soils. Here we review literature that supports a plant–soil feedback approach to understanding the ecology of metal-contaminated soil. Further, we discuss the idea that within these soils, the role of positive as opposed to negative plant–soil feedbacks may be more important. Testing this idea in a rigorous way in any ecosystem is challenging, and metal contamination imposes an additional abiotic constraint. We discuss research goals and experimental approaches to study plant–soil interactions applicable to metal-contaminated soils; these insights can be extended to other contaminated environments and restoration efforts.     

Evaluation of the RZWQM-CERES-Maize hybrid model for maize production

The root zone water quality model (RZWQM) was developed primarily for water quality research with a generic plant growth module primarily serving as a sink for plant nitrogen and water uptake. In this study, we coupled the CERES-Maize Version 3.5 crop growth model with RZWQM to provide RZWQM users with the option for selecting a more comprehensive plant growth model. In the hybrid model, RZWQM supplied CERES with daily soil water and nitrogen contents, soil temperature, and potential evapotranspiration, in addition to daily weather data. CERES-Maize supplied RZWQM with daily water and nitrogen uptake, and other plant growth variables (e.g., root distribution and leaf area index). The RZWQM-CERES hybrid model was evaluated with two well-documented experimental datasets distributed with DSSAT (Decision Support System for Agrotechnology Transfer) Version 3.5, which had various nitrogen and irrigation treatments. Simulation results were compared to the original DSSAT-CERES-Maize model. Both models used the same plant cultivar coefficients and the same soil parameters as distributed with DSSAT Version 3.5. The hybrid model provided similar maize prediction in terms of yield, biomass and leaf area index, as the DSSAT-CERES model when the same soil and crop parameters were used. No overall differences were found between the two models based on the paired t test, suggesting successful coupling of the two models. The hybrid model offers RZWQM users access to a rigorous new plant growth model and provides CERES-Maize users with a tool to address soil and water quality issues under different cropping systems.     

《园艺植物栽培学》实验教学改革与实践

在分析《园艺植物栽培学》实验教学现状的基础上,提出从教学方法、实验内容设置以及考核方法等方面对园艺植物栽培学实验教学进行改革,并阐述了实验教学改革取得的成效。     

EMS诱变谷子‘长农35号’突变体成熟期株型的鉴定与分析

[目的]建立谷子突变体库,以便在谷子分子生物学研究中应用。[方法]以生产上主要推广种植的谷子品种‘长农35号’干种子为实验材料,采用0.8%和1.0%甲磺酸乙酯（EMS）进行了诱变处理,并对所得突变体成熟期株型的7个表型形状进行考察,并据此对突变体进行分类。[结果]试验共收获株型相关的M1代突变体材料共282份,其中,0.8%EMS诱变‘长农35号’获得株型突变体材料100个单株,可分为10个组;1.0%EMS诱变‘长农35号’获得株型突变体材料182个单株,可分为17个组。M1代成熟期株型相关性状突变体分析结果表明：1.0%EMS处理‘长农35号’所获突变体,在株高、穗下节粗、穗下第一节间粗和茎节数4个性状与对照有显著差异,而0.8%处理与对照差异不显著。[结论]对于‘长农35号’来讲,采用1.0%EMS进行诱变处理更有利于多类型大量突变单株的获得。     

样品预处理方法对小麦和玉米叶子中内源激素质量分数的影响

高效液相色谱法已成为应用较为广泛的一种测定植物内源激素的方法,然而,植物体内其他内含物的存在常常干扰和影响检测结果,因而对植物材料预处理方法也提出了更高的要求。本试验以小麦和玉米叶片为材料,对目前几种常用的预处理方法进行比较。从高效液相色谱的测定结果来看,不同的预处理方法显著影响小麦叶子中IAA、GA和6-BA以及玉米叶子中IAA、GA、ZT、6-BA和ABA的检测质量分数。其中,仅用甲醇提取就进行高效液相色谱检测,得到激素质量分数不高;用甲醇提取、石油醚脱色后,加入PVP或PVPP去除杂质,经乙酸乙酯萃取,最后检测的激素质量分数也较低;而将样品用甲醇提取、经石油醚脱色和乙酸乙酯萃取、再过C18小柱的预处理过程,得到的各种激素质量分数最高。主效应分析结果表明,植物材料和处理方法对5种内源激素质量分数的影响均达到显著水平(P0.05),且植物材料的影响效应大于处理方法。因此,检测不同植物中的不同种类内源激素需要不同的方法;对小麦和玉米叶片,最后一种预处理过程是一种较为适宜的方法,其测定结果可能会更为准确地反映内源激素的质量分数。