甜高粱叶绿素荧光特性对生物有机液体混合肥的响应

为揭示生物有机液体混合肥对陕北农牧交错区青贮饲草作物光合作用的影响,以甜高粱(Sorghum bicolor L.)为研究对象,通过盆栽控制试验,设置4种浓度的生物活性水(BMW)(B1、B2、B3和B4,分别为稀释600、400、200和100倍的BMW溶液)和3种浓度的Aidoora溶液(A1、A2和A3,分别为稀释1000、500和300倍的Aidoora溶液)的生物有机液体肥处理,测定比较了不同生物有机液体混合肥下甜高粱叶片叶绿素荧光特性。结果表明:在大多数单一液体肥和混合液体肥下,适宜浓度水平的BMW和Aidoora溶液均能显著提高甜高粱幼苗叶片的PSⅡ最大光量子效率(F_v/F_m)、PSⅡ实际光化学量子效率(ΦPSⅡ)、光化学淬灭系数(qP)和表观光合电子传递速率(ETR),并降低了其非光化学淬灭系数(NPQ),且以有机液体混合肥的促进作用更显著,这说明施加生物有机液体肥后均能提高其叶片PSⅡ光化学效率和光合电子传递速率,而降低了非辐射性热能量耗散。综上分析表明,B2A2相对于其他BMW和Aidoora混合液体肥有利于促进甜高粱幼苗叶片PSⅡ光化学活性。     

铅胁迫对蔬菜根系形态的影响研究

通过营养液培养试验,铅胁迫对三种蔬菜根系生物量及根系形态影响表现为低浓度下（≤1 mg/L）的促进作用,随着处理浓度的提高（﹥2mg/L）,根系生物量及根长,根表面积,根体积均随之下降,抑制了根系的生长与发育。     

山西省小麦苗期根系性状及抗旱特性分析

小麦苗期根系形态是成株期根系分布的基础,与抗逆和产量密切相关,全面认识苗期根系及抗旱特性,对于抗旱优异种质的利用和早期筛选具有重要意义。采用239份山西省小麦品种(系)在土培条件下,研究了苗期根系性状及对水分胁迫的响应。结果表明,正常生长下山西小麦苗期根系性状多样性丰富,地方种变异最大;不同年代品种中,除最大根长随年代略下降外,其他性状均呈先升后降的趋势;不同根系性状对水分胁迫响应存在差异,总根长对水分最敏感,其次为根表面积、根体积和根生物量,最大根长和平均根数不敏感。苗期根系综合抗旱能力随年代呈先降后升的趋势,地方种和20世纪70年代品种多为中抗,80和90年代的品种抗旱性较低,2000年以后审定品种的抗性较高,其中旱地品种抗性最好。苗期根系抗旱特性与产量性状相关分析发现,最大根长、总根长、根体积和根生物量与雨养条件下的千粒重和产量显著正相关,最大根长和根生物量与成株期抗旱性也显著正相关。因此苗期最大根长和根生物量可作为半干旱地区旱地育种过程中抗旱性和产量的早期筛选指标。     

甬优系列籼粳杂交稻根系形态与生理特征

以甬优籼粳杂交稻群体(A)为研究对象,在稻麦两熟制机插高产栽培条件下,以三系杂交粳稻群体(B)、超级常规粳稻(C)和超级杂交籼稻群体(D)为对照的试验,旨在揭示甬优系列籼粳杂交稻超高产根系形态生理特征。结果表明:(1)在生育中、后期,A的根系干重、地上部干重、根尖数、根系长度、根系表面积、根系体积及根冠比均显著高于B、C和D。(2)抽穗期不定根(根径0.3 mm)的根尖数、根系长度、根系表面积和根系体积占总根的比例表现为A大于B和C,小于D;细分支(根径≤0.1 mm)与粗分支(0.1 mm根径≤0.3 mm)的根尖数、根系长度、根系表面积和根系体积占总根的比例均表现为A大于D,小于B和C。抽穗期土层0~5 cm、5~10 cm和10~15 cm范围根干重占根系总干重的比例表现为A大于B和C,小于D;土层15~25 cm、25~35 cm、35~45 cm、45~55 cm范围根干重占根系总干重的比例表现为A大于D,小于B和C。(3)A抽穗后根系总吸收面积、根系活跃吸收面积、根系伤流强度以及根系氧化力和根系还原力均高于B、C和D。与杂交粳稻、常规粳稻和杂交籼稻相比,甬优系列籼粳杂交稻具有根冠协调水平高、群体根量大、分支结构优、根系深扎性好以及中、后期生理活性强等优势,这种根系特征为其超高产的实现提供了重要保障。     

缺磷胁迫对黑籽南瓜幼苗根系生长和根系分泌物的影响

采用营养液培养方法,以1/2单位日本园试配方为基本营养液,在温室内培养黑籽南瓜(Cucurbita ficifolia B.)幼苗,测定正常供磷处理和缺磷胁迫下黑籽南瓜幼苗在根系生长、根系形态和根系分泌物等方面的差异,以期为南瓜磷高效种质创新和耐低磷机制研究提供理论依据.结果表明,缺磷胁迫后21 d,黑籽南瓜幼苗地上部生物量显著降低,根系生物量与正常供磷处理相比没有明显差异,根冠比增大;总根长和根表面积显著增加,根数、根横径和根体积与正常供磷处理相比没有明显的差异;根系吸磷量和磷转运率下降,根系吸磷量占总吸磷量的百分数增加,根系磷利用效率显著增高.总根长和根表面积增加可能与其磷吸收效率密切相关,是黑籽南瓜幼苗对缺磷胁迫的适应性变化.与正常供磷处理相比,缺磷胁迫后21 d,黑籽南瓜幼苗根系分泌的化合物种类组成类似,主要由酚类、芳香烃类、酯类、胺类、烯烃类和烷烃类化合物组成.但缺磷胁迫后根系分泌物中的化学成分多于正常供磷处理,邻苯二甲酸二(1丁基2异丁基)酯等8种化合物是缺磷胁迫下黑籽南瓜根系分泌物的特有成分.缺磷胁迫后黑籽南瓜的自毒作用增强.     

玉米自交系幼苗生物量积累及根系形态对两种氮素水平的反应及聚类分析

为探讨低氮胁迫对玉米自交系幼苗生物量和根系形态的影响,以35份玉米自交系为材料,测定了两个氮素水平处理后14d玉米幼苗的单株干重、地上部干重、根干重、根冠比、总根长、根表面积、根体积、根平均直径、侧根数和初生根长。结果表明,低氮胁迫下玉米幼苗根干重、根冠比、根总表面积、根体积、侧根数、根平均直径和初生根长显著增加,地上部干重和单株干重显著减小,而总根长没有明显变化。通过主成分分析和聚类分析发现,同一氮素水平下,玉米幼苗各性状的综合表现存在基因型差异,且在正常氮素和低氮条件下均可以分为6组。低氮处理后,选取的9个自交系地上部氮素积累量均显著降低,PH4CV、B73和XY4的根系氮素积累量显著增加,其余6个自交系显著降低。此外,只有XY4的氮素吸收和利用效率均较高。综合分析表明,XY4是低氮高效型玉米自交系。     

籼、粳超级稻品种根系形态及若干生理特征的差异

为阐明籼、粳超级稻根系干物质积累与分布特征和主要形态生理性状指标的差异及其与产量形成的关系,以当地主体且具有代表性的2个超级杂交籼稻组合和2个常规粳型超级稻品种为试验材料,对麦稻两熟制条件下籼、粳超级稻单茎和群体根干重、总根长、根数、根体积、根系吸收面积、发根力、抽穗后根系伤流强度及根冠比、每条根长、根直径、根密度、颖花根流量、抽穗期根系在土层中的分布和产量构成等方面进行了系统的比较研究。结果表明：(1)整个生育期,粳稻的根冠比、每条根长、发根数、发根体积、发根干重及颖花根流量、穗数、群体颖花量、结实率和实收产量均高于籼稻,而根直径、每穗粒数和千粒重低于籼稻,其中根冠比、每条根长、颖花根流量、穗数、每穗粒数、结实率和实收产量差异达显著或极显著水平;(2)粳稻抽穗前(含抽穗期)单茎根干重、总根长、根数、根体积和根系总吸收表面积及根密度均低于籼稻,但差异不显著,而成熟期这6个指标粳稻均显著或极显著高于籼稻;(3)粳稻拔节前单茎活跃吸收表面积和活跃吸收表面积比均小于籼稻,而拔节后(含拔节期)两者差异趋势与之相反,差异显著或极显著;(4)除拔节期群体根干重、拔节期和抽穗期群体根数外,其他群体形态生理特征指标粳稻均显著或极显著高于籼稻;(5)无论是单茎还是群体,粳稻抽穗后0~35 d根系伤流量均显著或极显著高于籼稻;(6)粳稻0~10 cm土层根系干重所占比例极显著低于籼稻,10 cm以下土层根系干重占根系总干重的比例极显著高于籼稻,粳稻扎根更深,进一步强化了植株抗倒防早衰能力。与超级杂交籼稻相比,常规粳型超级稻抽穗后根系生长优势不断加大,特别是群体生长优势,成熟期粳稻所有根系形态生理特征指标均优于籼稻,是粳稻高产形成的重要原因和保障。     

不同磷效率大豆基因型根形态构型对低磷胁迫的响应

探讨大豆根系形态构型指标在低磷胁迫下的适应性反应,研究根系形态构型指标与磷效率的关系。本试验选用3个“磷低效”大豆基因型D3、D17和D18及“磷高效”大豆基因型D34、D37和D38,采用田间试验,设高、低磷两个处理,对大豆基因型磷效率与根形态构型指标的关系进行了研究。结果表明,在高磷处理下,供试大豆根系各形态构型指标和根干生物量均无显著差异,在低磷处理下,各基因型间差异达到显著水平。相关分析表明,根长、根表面积和根生物量与地上部干生物量达到显著或极显著正相关,根直径与磷效率相关系数未达到显著水平。低磷胁迫时,根长、根表面积与根生物量影响植物的磷效率,而根直径对磷效率的影响较小。因此可以把根长、根表面积作为大豆磷效率筛选的重要指标,把根生物量作为辅助筛选指标。     

玉米根系分泌碳、氮动态及与根系特征的关系

为深入认识玉米根系分泌碳、氮规律及其与根系特征的关系,以玉米品种‘迪卡653’为材料,采用土培-水培相结合的方法,测定了玉米根系形态指标和根系分泌物中碳、氮的含量。结果表明,玉米根系碳、氮分泌比强度(EI_root-C、EI_root-N)在生育前期高于生育后期,与比根长、比根表面积、比根体积呈显著正线性相关,而与根系C/N比呈显著负线性相关;玉米单株碳、氮分泌强度(EI_plant-C、EI_plant-N)在生育期内呈先升高后降低的趋势,累积分泌碳15.71 g/plant,累积分泌氮0.75 g/plant;EI_plant-C与根长、根表面积、根体积、根干重、根冠比、叶面积之间均存在极显著二次曲线关系,而EI_plant-N仅与根冠比之间有显著二次曲线关系。依据玉米根系特征与根系分泌碳、氮的定量关系,可为估算大田种植下玉米根系分泌碳、氮量提供参考。     

利用“永久F2”群体进行小麦幼苗根系性状QTL分析

为了研究小麦苗期根系性状的遗传,以小麦品种花培3号和豫麦57的杂交DH群体组配了一套含168个杂交组合的“永久F₂”群体。利用WinRHIZO根系分析系统测定四叶一心期小麦水培幼苗根系总长度、直径、表面积、体积、根尖数、最大根长、茎叶干重、根干重及根茎干重比9个性状。采用复合区间作图法分析幼苗根系8个性状的QTL,定位了7个加性效应QTL和12对上位性互作QTL,包括加性效应、显性效应,加加互作、加显互作和显显互作,分布在1A、1D、2A、2B、2D、3A、3B、5D、6D和7D染色体上,单个QTL可解释0.01%~11.91%的遗传变异。在染色体2D上XWMC41至XBARC349.2区间检测到同时控制总根长和根干重的一个QTL。上位性对苗期根系生长发育有重要作用。试验结果表明,苗期根系性状的遗传机制较复杂, 因此在育种中要综合考虑根系各性状之间的关系,保证根系协调统一、发达健壮。     

施磷量对黑木相思苗木生长的影响

为探究黒木相思苗木生长变化对磷肥的反映机制,本研究对1a生黑木相思(Acacia melanoxylon)苗木采用随机区组设计,设置了7个不同施肥量处理(0、50、75、100、125、150、200 mg P/株),测定并分析其苗高、地径、生物量及根系形态指标。结果表明：不同施磷量对苗木高生长、地径、生物量(地上部分、地下部分生物量)以及根系的生长都起促进作用,随时间和施磷量的增加,黑木相思根长、根平均直径、根表面积、根体积、苗高、地径、生物量总体表现均有所增加,总量为100 mg/株的等量施磷量对苗木生长促进作用效果最佳,试验结束时(即施肥第12 wk),该处理的根长、根表面积、根平均直径、根体积、苗高、地径、生物量(地上、地下部分)分别为417.09 cm、35.16 cm2、0.46cm、0.48cm3、36.2mm、2.30mm、1.236g(地上部分)、0.227g(地下部分),其中根长、根表面积、根平均直径、根体积分别比对照增加了81.2%、110.7%、61.2%和127.1%。     

Comparison of Drought Tolerance of Maize,Sweet Sorghum and Sorghum‐Sudangrass Hybrids

In drought‐prone environments, sweet sorghum and sorghum‐sudangrass hybrids are considered worthy alternatives to maize for biogas production. The biomass productivity of the three crops was compared by growing them side‐by‐side in a rain‐out shelter under different levels of plant available soil water (PASW) during the growing periods of 2008 to 2010 at Braunschweig, Germany. All crops were established under high levels of soil water. Thereafter, the crops either remained at the wet level (60–80 % PASW) or were subjected to moderate (40–50 % PASW) and severe drought stress (15–25 % PASW). While the above‐ground dry weight (ADW) of sweet sorghum and maize was insignificantly different under well‐watered conditions, sweet sorghum under severe drought stress produced 27 % more ADW than maize. The ADW of sorghum‐sudangrass hybrids significantly lagged behind sweet sorghum at all levels of water supply. The three crops differed markedly in their susceptibility to water shortage. Severe drought stress reduced the ADW of maize by 51 %, but only by 37 % for sweet sorghum and 35 % for sorghum‐sudangrass hybrids. The post‐harvest root dry weight (RDW) in the 0–100 cm soil layer for maize, sweet sorghum and sorghum‐sudangrass hybrids averaged 4.4, 6.1 and 2.9 t ha^?1 under wet and 1.9, 5.7 and 2.4 t ha^?1 under severe drought stress. Under these most dry conditions, the sorghum crops had relatively higher RDW and root length density (RLD) in the deeper soil layers than maize. The subsoil RDW proportion (20–100 vs. 0–20 cm) for maize, sweet sorghum and sorghum‐sudangrass hybrids amounted to 6 %, 10 % and 20 %. The higher ADM of sweet sorghum compared with maize under dry conditions is most likely attributable to the deep root penetration and high proportion of roots in the subsoil, which confers the sorghum crop a high water uptake capacity.     

重金属铅镉对甜高粱生长的影响及其积累特性研究

旨在为甜高粱在修复土壤重金属污染领域的应用提供理论支撑。以甜高粱品种‘辽甜1 号’为供试材料,采用土壤盆栽试验研究不同浓度铅、镉及其复合污染作用下甜高粱的生长响应及重金属吸收、富集和迁移特征变化。结果表明：低浓度Pb(≤100 mg/kg)、Cd(≤1 mg/kg)处理促进了甜高粱的生长,高浓度Pb(≥1000 mg/kg)、Cd(≥10 mg/kg)则呈现出抑制效应,根长、株高、穗长和生物量均显著减小。甜高粱各部位重金属含量随着土壤Pb、Cd处理浓度的升高而增加,其中重金属Pb的含量大小顺序为根＞叶＞茎＞穗,重金属Cd的含量大小顺序为根＞茎＞叶＞穗,且甜高粱对Cd的富集系数和转运系数均显著高于Pb。由此可知,甜高粱品种‘辽甜1 号’对重金属Pb、Cd具有较强的抗逆性和较好的吸收积累和转运能力,其在Pb、Cd单一及其复合污染土壤修复方面具有潜在的应用价值。     

Genetic variation for maize root architecture in response to drought stress at the seedling stage

Although the root system is indispensable for absorption of nutrients and water, it is poorly studied in maize owing to the difficulties of direct measurement of roots. Here, 103 maize lines were used to compare root architectures under well-watered and water-stressed conditions. Significant genetic variation, with medium to high heritability and significant correlations, was observed for root traits. Total root length (TRL) and total root surface area (TSA) had high phenotypical diversity, and TRL was positively correlated with TSA, root volume, and root forks. The first two principal components explained 94.01% and 91.15% of total root variation in well-watered and water-stressed conditions, respectively. Thus, TRL and TSA, major contributors to root variation, can be used as favorable selection criteria at the seedling stage. We found that stiff stalk and non-stiff stalk groups (temperate backgrounds) showed relatively higher mean values for root morphological diversity than the TST group (tropical/subtropical background). Of the tested lines, 7, 42, 45, and 9 were classified as drought sensitive, moderately sensitive, moderately drought tolerant, and highly drought tolerant, respectively. Seven of the 9 extremely drought tolerant lines were from the TST group, suggesting that TST germplasms harbor valuable genetic resources for drought tolerance that could be used in breeding to improve abiotic stress tolerance in maize.     

不同施钾量条件下甘薯块根形成的内源激素变化及其与块根数量的关系

In order to explore the changes of endogenous hormones on storage root formation and its relationship with storage root number under different potassium application rates of sweet potato root, sweet potato varieties ‘Yanshu 25’ and ‘Beijing 553’ with significant differences in storage root number were used as experimental materials, potassium oxide (K₂O) was used as fertilizer, and four potassium fertilizer gradients of 0 (K0), 120 (K2), 240 (K3), and 360 kg hm^-2 (K4) were set. The effects of different potassium application rates on the contents of endogenous hormones, the activity of related metabolic enzymes, the number of storage root and root evenness in swelling roots of sweet potato during root formation and harvest stage were studied. Compared with the treatment without potassium fertilizer (K0), the application of potassium fertilizer decreased the enzyme activities of indoleacetic acid oxidase (IAAO) and peroxidase (POD), increased the content of indole-3-acetic acid (IAA), increased the content of zeatin riboside (ZR) and decreased the content of gibberellins (GA₃). Potassium application enhanced the activity of primary cambium and promoted the differentiation from adventitious root to storage root by regulating the content of endogenous hormones in swelling roots of sweet potato. Compared with the control, the application of potash fertilizer significantly increased the number and weight of storage roots per plant and root yield of ‘Yanshu 25’ and ‘Beijing 553’. The number of storage roots per plant of ‘Yanshu 25’ and ‘Beijing 553’ increased by 3.16%-25.40% and 3.85%-33.11%, respectively, and the yield increased by 4.22%-17.31% and 3.94%-18.45%, respectively. Compared with the potassium application treatments of the two varieties, the K2 treatment had the highest storage roots number per plant, the highest weight and yield of storage roots, with the best root evenness.     

钠盐胁迫对甜高粱种子萌发及幼苗生长的探究

为探讨甜高粱种子在不同钠盐胁迫下的萌发特性,本研究以‘辽甜1号’甜高粱种子为材料,采用不同浓度钠盐(NaCl,Na HCO3,Na2SO4及其复合钠盐)溶液进行处理,分析比较甜高粱种子萌发阶段对不同钠盐胁迫的响应特性。结果表明,随着盐浓度的增加,总体上甜高粱种子的发芽率、发芽势、发芽指数、活力指数等萌发指标呈现逐渐降低趋势,不同浓度的钠盐胁迫均显著抑制甜高粱种子的干物质转移和早期幼苗的生长(p<0.05),对幼根的抑制高于幼芽。主成分分析(PCA)结果表明,PC1主要包含芽干重、根干重、根长、活力指数,代表"生长综合因子"(85.87%),PC2主要包含发芽率、发芽势、发芽速度,代表"速率综合因子"(8.36%)。二者共同解释12个萌发指标的94.23%的信息。运用隶属函数法评价不同浓度钠盐胁迫下甜高粱种子的毒害作用,在Na+浓度相同的条件下,不同组成钠盐对甜高粱种子萌发的抑制程度高低为NaHCO3>复合钠盐>NaCl>Na2SO4。     

施用2种牛粪发酵肥对甜高粱生长量的影响

为探讨牛粪沼液和堆肥对饲用甜高粱(Sorghum bicolor)生长量等指标影响程度,确定种植甜高粱的适宜肥料,通过大区对比试验,观测分析施用牛粪沼液和堆肥的甜高粱株高、茎粗和叶宽的生长率。结果表明,施用牛粪堆肥和沼液的甜高粱株高生长率约为不施肥处理的1.12倍和1.02倍,施牛粪堆肥的甜高粱株高的平均生长率是施用沼液的1.09倍,施沼液的甜高粱株高高度有2个时期大于施用牛粪堆肥的,但是施用牛粪堆肥的甜高粱总株高较大。施用沼液的甜高粱茎粗生长率是对照的2.8倍,是牛粪堆肥的1.87倍。施牛粪堆肥的平均叶宽生长率是沼液的1.09倍,且生长持续时间较长。牛粪堆肥的腐殖酸和全氮量较大,增加了甜高粱株高及叶生长率,适宜做基肥;沼液速效钾、硝态氮和铵态氮的量较大,增加了甜高粱茎粗生长率,能短期促进生长,既可做基肥也可做追肥施用。     

Einfluß von Form und Plazierung der N- und P-Düngung auf Wurzelentwicklung, Phosphat-Aufnahme und Wachstum von Sonnenblumen (Helianthus annuus) und Zuckerhirsen (Sorghum bicolor)

Influence of form and placement of N- and P-fertilisation on the root development, the P-uptake, and the growth of sunflower ( Helianthus annum ) and sweet sorghum ( Sorghum bicolor ).
In pot- and rhizotrone-experiments with Sorghum bicolor and Helianthus annuus , a higher P-uptake was achieved by placement of diammonphosphate (DAP) than by either placement of triplesuperphosphate (TSP) or by broadcasting DAP or TSP, respectively. Dual placement of TSP and ammonia increased the P uptake but it was less effective than placement of DAP for sunflowers, but not for sweet sorghum. Placement of nitrogen resulted in a local root accumulation, where ammonia had a greater effect than nitrate for both of the species. Single placement of TSP had no effect on either P uptake or root development.
Thus, the higher P uptake at DAP placement could be attributed to three main factors: the local root accumulation caused by the placement of nitrogen, a specific physiological ammonia-effect, and the lower binding intensity of the phosphate in the DAP-band compared with placed TSP (W erner and S trasser 1993). The improvement in spatial availability caused by the NH₄⁺ -induced root accumulation was of a greater importance for the P-uptake than was the improvement of chemical availability in the DAP-band. The better response of sunflowers in comparison with sweet sorghum was attributed to better acquisition ability in sweet sorghum.     

尾巨桉幼苗根系分布及生物量特征研究

为了探讨不同肥料种类、施肥量对尾巨桉1年生幼苗根系生长的影响,为桉树生态经营提供科学依据,采用4因素3水平进行正交试验,4因素为氮肥、磷肥、钾肥和桉树专用肥,3水平为磷肥2 g、6 g、12 g,氮肥、钾肥和桉树专用肥为1 g、3 g和6 g。对尾巨桉根系采取全根挖掘法,测定根系垂直分布和水平分布范围,称其鲜质量,进行生物量测定,统计分析数据。结果表明：（1）对尾巨桉根系垂直分布范围影响最大的为磷肥,其他3种肥料对其分布的影响差异不显著,远小于磷肥的影响。各种施肥根系的垂直分布为32~57 cm;（2）对尾巨桉根系水平分布范围最大的为桉树专用肥。根系水平分布为57~86 cm;（3）对尾巨桉根尖数量影响最大的为氮肥,是最主要因素,其他3种影响相差不大。根尖数量为47~71个;（4）对尾巨桉根系1级侧根的根长影响最大的为桉树专用肥,是最主要因素。根系1级侧根的根长范围15.2~30.5 cm;（5）根系直径在0~2.0 mm、2.1~5.0 mm、5.1~10.0 mm及大于10.1 mm的根系生物量分别为0.879~2.718 g、2.141~3.663 g、0.841~7.268 g和5.179~17.628 g,呈现出随根系直径增加而递增的趋势;（6）不同施肥处理根系总生物量达14.739~29.336 g。施磷肥对尾巨桉根系总生物量的影响最显著。