不同灌水量对水、旱稻营养生长和光合特性及其产量的影响

以中旱3号（常规旱稻）和汕优63（杂交水稻）为材料,研究5种不同灌水量处理对水稻和旱稻营养生长、光合特性以及产量的影响。结果表明,不同的灌水量处理明显影响水稻和旱稻的营养生长,光合特性以及产量。汕优63在处理A（灌溉水量为对照的25%）和处理B（灌溉水量为对照的43.75%）时,产量受到严重影响,分别比对照（处理E）减产80.58%和42.98%,差异极显著;在处理C（灌溉水量为对照的62.5%）和处理D（灌溉水量为对照的81.25%）时,与对照产量差异不显著。中旱3号在处理A时比对照减产68.42%,差异极显著;籽粒产量在处理B～E之间没有显著差异。这一特点在所有测定的其他营养生长和光合指标上也表现的非常明显。汕优63、中旱3号获得最高产量的灌溉需水量分别为每公顷7 500 m3和每公顷5 250 m3。超过此值,随着灌水量的增加,产量将有所下降。旱稻获得最高产量的灌溉水量比水稻约可节约30%,节水潜力巨大。在所有灌溉水量处理下,旱稻的产量比水稻的产量均低,有效穗数少是其主要原因。     

水稻减数分裂期颖花中激素对水分胁迫的响应

以旱A-3 (HA-3, 抗旱性品种)和武运粳7号(WY-7, 干旱敏感品种)为材料, 在减数分裂期(抽穗前15~2 d)进行充分灌溉(WW)和土壤水分胁迫(WS)处理。结果表明, WS处理显著降低叶片水势, 但穗水势没有变化。WS处理的颖花不孕率, WY-7较WW增加58.5%~50.9%, HA-3仅较WW增加12.6%~12.8%。颖花中的玉米素＋玉米素核苷、吲哚-3-乙酸和赤霉素(GA₁+GA₄)浓度在WW与WS处理间以及在两品种间无显著差异。WS显著增加颖花中脱落酸(ABA)、乙烯和1-氨基环丙烷-1-羧酸浓度。WY-7乙烯的增加超过ABA的增加, 而HA-3乙烯与ABA增加量大致相等。在减数分裂早期对WS稻穗施用氨基-乙氧基乙烯基甘氨酸(乙烯合成抑制剂)和ABA, 颖花的不孕率显著降低; 施用乙烯利(乙烯释放促进物质)和氟草酮(ABA合成抑制物质), 结果则相反。上述结果说明, 在减数分裂期遭受水分胁迫, 内源ABA和乙烯的相互拮抗作用调控颖花的育性, 较高ABA与乙烯的比值是水稻适应水分逆境的一个生理特征。     

结实期灌溉方式对水稻品质和不同器官镉浓度与分配的影响

旨在探讨在土壤镉（Cd）污染条件下,能否通过合适的灌溉方式改善稻米品质并减少Cd在籽粒中的分配。盆栽扬粳9538（粳稻）和扬稻6号（籼稻）,于移栽前加Cd 150 mg kg-1（Cd处理）,以未加Cd为对照（CK）。自抽穗后7 d至成熟设置3种灌溉方式,即保持水层(WW);轻干-湿交替灌溉(MD,土壤落干至土壤水势为－20 kPa时复水);重干-湿交替灌溉(SD,土壤落干至土壤水势为－40 kPa时复水)。结果表明,在土壤Cd浓度相同条件下,与WW比较,MD显著增加结实率、千粒重、产量、稻米的出糙率、精米率和整精米率,显著降低垩白度,SD的结果则相反。Cd处理对结实率、千粒重和稻米品质各指标无显著影响。在Cd处理条件下,与WW相比,MD和SD显著增加Cd在根系的浓度和分配比例,降低Cd在茎叶的浓度和在籽粒的分配比例。籽粒和精米中Cd浓度,SD显著高于WW,MD与WW无显著差异。Cd在精米的分配比例则SD显著低于MD和WW。两品种结果趋势一致。说明结实期轻干-湿交替灌溉可以增加产量、改善稻米的加工和外观品质,并可不增加甚至降低Cd在籽粒中的浓度及分配比例。从根系活性、叶片光合特性以及Cd的转运等方面分析了在不同灌溉方式下产量、品质及不同器官Cd浓度与分配差异的原因。     

温敏核不育系株1S籼粳属性研究

温敏核不育系株1S是生产上广泛应用的水稻优良早籼型不育系品种。以典型籼稻和粳稻为对照,采用ISSR、SRAP和TRAP三种分子标记方法对株1S核DNA进行分子遗传学分析,结果表明,株1S核DNA以籼型基因为主,但含有部分粳型特异性片段,具有一定的粳型血缘;3种分子标记方法都能建立株1S所特有的分子指纹。对株1S叶绿体DNA中ORF100、ORF29-TrnC^GCA、TrnT^UGU–TrnL^UAA、rps16基因内含子等序列分析表明,株1S为籼型叶绿体,对照材料培矮64S、准S为粳型叶绿体;株1S在TrnT^UGU–TrnL^UAA片段中存在两个特异碱基。利用籼型细胞质和含有适量粳稻血缘的两用核不育系可能是长江中下游双季稻区高产稳产早稻组合的育种途径。     

Using profitable chrysanthemums for phytoremediation of Cd- and Zn-contaminated soils in the suburb of Shanghai

Purpose

We studied the profitable phytoremediation method with commercial chrysanthemum (Chrysanthemum indicum L.) in order to remediate the soils contaminated with heavy metals and generate economy income from the contaminated sites.

Materials and methods

A field experiment was carried out to remediate the contaminated soil through growing the commercial chrysanthemum plants in a farmland polluted with heavy metals of Cd and Zn due to application of creek sediments in the western suburb of Shanghai, Southeast China, since June 2013.

Results and discussion

After the consecutive 3 years of phytoremediation, Cd and Zn contents in the soil were reduced by 78.1% and 28.4%, respectively. We also found that the rice grain growing on the 3-year phytoremediated soil met the requirements of dietary safety, so did the vegetable growing on the 5-year phytoremediated soil.

Conclusions

Growing chrysanthemum plants as a method of phytoremediation can not only remove a large amount of toxic heavy metals from the contaminated soil but also be highly profitable from the sales of chrysanthemum flowers.

     

水杉种子挥发物质的鉴定及其抗菌活性测定

采用气质联用仪(GC-MS)测定水杉种子挥发油的化学组成,并采用生长速率法测定水杉种子挥发油对梨黑斑病菌(Alternaria kikuchiana)、苹果霉心病菌(A.alternata)、大蒜叶枯病菌(Stemphylium botryosum)、莴苣灰霉病菌(Botrytis cinerea)、小麦赤霉病菌(Fusarium graminearum)、茶轮斑病菌(Pestalotiopsis theae)、构骨炭疽病菌(Colletotrichum sp.)和大葱紫斑病菌(A.porri)8种植物病原真菌生长的影响。结果表明:水杉种子挥发油的主要成分为1R-α-蒎烯(46.355%)、柠檬烯(13.663%)、(1S-内型)-1,7,7-三甲基-二环[2.2.1]庚-2-醇乙酸酯(6.941%)、石竹烯氧化物(6.924%)、β-蒎烯(4.902%)、(1S)-6,6-二甲基-2-亚甲基-二环[3.1.1]庚烷(4.807%)等。水杉种子挥发油对8种植物病原真菌均有一定的抑制作用,其中100μL·培养皿-1剂量对大蒜叶枯病菌、小麦赤霉病菌、茶轮斑病菌的抑菌率在60%以上。本研究表明,水杉种子挥发物质中含有多种活性成分,在医药化工等方面有着广阔的应用前景,在农业上有一定的开发价值。     

Genetic variation within and among populations of <Emphasis Type="Italic">Orychophragmus violaceus</Emphasis> (Cruciferae) in China as detected by ISSR analysis

Orychophragmus violaceus, a ground covering plant that is widely distributed in China. It has both high economical value in food, forage, health care and ornamental value in gardening. In this study, the genetic diversity of 245 individuals from nine populations in China were investigated using the inter-simple sequence repeat markers. Of the 100 primers screened, eight were highly polymorphic. Using these primers, 162 discernible DNA fragments were generated with 150 (92.59%) being polymorphic, indicating a pronounced genetic variation at the species level. Also, there were high levels of polymorphism at the population level with the percentage of polymorphic bands ranging from 85.74 to 90.06%. Analysis of molecular variance showed that the genetic variation within populations was 80.80% and the variance among populations was 16.43%. The Nei’s G _ST (0.1643) and gene flow among populations (Nm = 2.5760) revealed large gene exchanges among populations. O. violaceus belongs to out-crossing plants. It is capable of reproducing by self-sowing, thus can influence population genetic structure. The pronounced genetic variation within populations tells us that O. violaceus is a proper plant for genetic research and that there is great potential of breeding this species for gardening.     

灌溉水质与灌溉沟坡度对华北土壤径流和侵蚀的影响

Irrigation-induced soil erosion seriously affects the sustainability of irrigated agriculture. The effects of irrigation water quality and furrow gradient on runoff and soil loss were studied under simulated furrow irrigation in laboratory using a soil collected from an experimental station of China Agricultural University, North China. The experimental treatments were different combinations of irrigation water salt concentrations of 5, 10, 20, and 30 mmol_c L^-1, sodium adsorption ratios (SAR) of 0.5, 5.0, and 10.0 (mmol_c L^-1)^0.5, and furrow gradients of 1%, 3%, and 5%, with distilled water for irrigation at 3 furrow gradients as controls. The experimental data indicated that total runoff amount, sediment concentration in runoff, and total soil loss amount generally decreased with increasing salt concentration in irrigation water but increased with its sodicity and furrow gradient. The effects of water quality and furrow gradient on soil loss were greater than those on runoff, and the increase of furrow gradient decreased the influence of water quality on soil loss. When the salt concentration increased from 5 to 30 mmol_c L^-1 at SAR of 10.0 (mmol_c L^-1)^0.5, total runoff amount, sediment concentration, and total soil loss amount decreased by 3.89%, 52.1%, and 53.92%, and 10.57%, 38.86%, and 42.03% at the furrow gradients of 1% and 5%, respectively. However, they respectively increased by 3.37%, 45.34%, and 55.36%, and 3.86%, 10.77%, and 13.91% when SAR increased from 0.5 to 10.0 (mmol_c L^-1)^0.5 at the salt concentration of 5 mmol_c L^-1. Irrigation water quality and furrow gradient should be comprehensively considered in the planning and management of furrow irrigation practices to decrease soil loss and improve water utilization efficiency.     

水稻第2染色体上抗旱相关性状QTL的精细定位

水资源危机使得水稻抗旱性的遗传与育种研究成为当今的研究热点之一。鉴定与水稻抗旱性直接相关的性状和产量的QTL,可为通过标记辅助选择培育抗旱水稻品种提供标记信息。以从供体IRAT109渗入到珍汕97B背景的269个高代回交渗入系中筛选出覆盖第2染色体目标区段的87个近等基因系为材料,在抗旱鉴定大棚中采用控制式供水,精细定位了水处理(对照)与干旱胁迫条件下影响水稻水分生理及产量相关性状的QTL。共检测到20个影响叶水势(LWP)、冠层温度(CT)、茎基粗(BCT)等性状相关QTL和百粒重(HGW)、每穗颖花数(SN)、着粒密度(SPD)等产量相关QTL。根据在不同环境下的表达情况,将其分为3类,第1类7个QTL,在两种环境下均被检测到;第2类4个,只在对照条件下检测到;第3类2个,分别控制叶水势和颈基粗,受干旱胁迫诱导,只在胁迫条件下被检测到,其中,叶水势定位在RIO02037-RIO02038约8.2 kb的区段上, 其加性效应和贡献率分别为-1.0361和13.03%,增效等位基因来自IRAT109;茎基粗定位在RIO02017-RIO02022约37.7 kb的区段内,加性效应和贡献率分别为0.2682和49.20%,增效等位基因来自珍汕97B。在水、旱2种条件下均检测到的相对稳定的7个QTL及干旱胁迫条件下的2个QTL可能对抗旱性有直接贡献。     

不同播种技术对非林地人参育苗的种苗质量的影响

非林地人参育苗是非林地种植人参成功的关键,为获得非林地人参高产优质种苗,本文通过研究不同播种技术对非林地人参育苗及种苗质量的影响,确定最适宜播种技术为机械播种,播种密度为3cm×3cm。