旱地高产小麦品种籽粒锌含量差异与产量构成和锌吸收利用的关系

【目的】 明确旱地条件下高产小麦品种籽粒锌含量差异与产量构成及锌吸收利用的关系,对通过品种选育和施肥调控提高旱地小麦籽粒产量和锌营养,实现小麦高产优质生产有重要意义。 【方法】 于2013—2016年连续三年在黄土高原典型旱地进行了小麦裂区田间试验。 以我国主要麦区的123个小麦品种为试材,每个品种设置不施肥和施N 150 kg/hm2、P₂O₅ 100 kg/hm2两个处理。分析了高产小麦籽粒锌含量差异及其与干物质累积、产量构成、锌吸收和分配之间的关系。 【结果】 施肥条件下,高产小麦品种籽粒锌含量存在显著差异,小麦籽粒锌含量与籽粒产量间无显著相关性,但与千粒重、锌吸收量、锌收获指数和籽粒锌形成效率呈显著正相关,与穗粒数呈显著负相关。在高产品种中,无论施肥与否高锌品种的籽粒锌含量均显著高于低锌品种;高锌品种的籽粒锌含量因施肥而显著提高,低锌品种却降低。施肥条件下,高锌品种的籽粒产量、生物量和收获指数与低锌品种相比无显著差异,穗数却显著降低;高锌品种的籽粒锌吸收量、地上部锌吸收量、锌收获指数和籽粒锌形成效率均显著高于低锌品种。且高锌品种的产量、生物量、穗数、穗粒数和锌吸收量因施肥引起的提高幅度均亦显著高于低锌品种。 【结论】 在黄土高原旱地低锌土壤上,无论是品种选育还是施肥调控,促进小麦锌的吸收和向籽粒的转移是提高小麦籽粒锌含量的关键。      

多小穗小麦10-A EMS突变株系的农艺性状评价

为深入了解多小穗小麦种质10-A EMS突变株系的表现,对经0.8%甲基磺酸乙酯(EMS)诱变种子产生的M₄突变株系群体的12个农艺性状进行了评价。结果表明,222个突变株系间在株高、穗长、总小穗数、总分蘖数、有效分蘖数、穗粒数、单株产量等性状上差异极显著,群体具有丰富的变异。其中,突变株系群体中单株产量、总分蘖数、有效分蘖数、千粒重和穗粒数的变异系数均大于20%,而抽穗期、小穗数、籽粒直线宽和籽粒直线长的变异系数均小于10%。多重比较表明,在株高、穗长、总小穗数、总分蘖数、有效分蘖数、穗粒数和单株产量等性状上均能筛选到与10-A差异显著或极显著的突变株系。简单相关分析表明,突变株系的穗长与小穗数、穗粒数、抽穗期呈极显著正相关,与单株产量、千粒重、籽粒投影面积呈极显著负相关;突变株系的小穗数与穗粒数呈极显著正相关,与千粒重、籽粒投影面积呈极显著负相关。聚类分析可将所有突变株系材料分为七类,其中192份突变株系与10-A聚为类Ⅰ,其中亚类ⅠA和ⅠC材料的穗粒数和千粒重都较高,25份材料聚为类Ⅱ,而其他五类每类均只含有1份突变株系。本研究结果为深入了解小麦农艺性状的遗传规律和突变株系的遗传研究与育种利用提供了参考。     

Chlorophyll meter as nitrogen management tool in malting barley

Abstract

Variable precipitation in many regions makes it difficult to predict yield goals and nitrogen (N) rates for malting grade barley (Hordeum vulgare L.). During years with below normal growing season precipitation, barley fertilized at the recommended rate often exhibits grain protein concentrations exceeding what is acceptable for malting. A study was conducted to evaluate the chlorophyll meter as a N management tool. Barley was grown under several N rates in the field. Chlorophyll meter readings and N additions were made at the Haun 4 to 5 growth stage, and grain yield and protein concentrations were evaluated at maturity. Chlorophyll meter readings, normalized as meter reading from treatment plot divided by that from a plot receiving a full N treatment at the Haun 4 to 5 growth stage, were correlated with grain yield (r²=0.67). Stands having normalized chlorophyll meter readings below 95% responded to N additions with yields equivalent to the fully fertilized stand and grain protein concentrations acceptable for malting. A N management strategy is proposed whereby 40 to 50% of the N calculated for the yield goal is applied at planting and a fully fertilized reference strip is included for each variety or soil type. At the Haun 4 to 5 growth stage, chlorophyll meter readings are taken in the reference strip and in the field. Normalized chlorophyll meter readings below 95% of the reference strip indicate a need for additional N fertilizer. This strategy will provide producers with additional time (up to a month) to evaluate growing season conditions before investing in additional crop inputs and will improve the likelihood that a barley crop acceptable for malting will be produced.     

Effect of Elevated [CO2] on Assimilation,Allocation of Nitrogen and Phosphorus by Maize (Zea Mays L.)

To estimate the effect of elevated [CO₂] on nitrogen (N) and phosphorus (P) dynamics and productivity in summer maize, a field experiment was conducted in open-top chambers (OTCs) at different [CO₂] (550 μmol/mol, T1; 750 μmol/mol, T2 and a control, CK) in Nanjing in Jiangsu Province, China. The results showed that maize total N and P accumulation were 13.23–66.56% higher in the elevated [CO₂] treatments than in the CK plots during the jointing, anthesis and maturity stages. There was only a significant difference in total N accumulation between the T2 treatment and CK at maturity (P < 0.05). However, rising [CO₂] decreased the N and P concentrations in each biomass fraction. Elevated [CO₂] increased the amounts of N and P translocation, resulting in the contribution of translocated N to grain N. Similarly, rising [CO₂] increased N and P translocation efficiencies, N or P harvest index, and N or P utilization efficiency based on grain yield and N or P utilization efficiencies based on biomass in both growing seasons. In addition, elevated [CO₂] significantly increased aboveground biomass at three stages, including 4.73–12.34% at maturity. The grain yields of summer maize increased by 21.28% and 29.07% in the two elevated [CO₂] plots. Furthermore, spike numbers, kernels per spike and 100-grain weight were increased by elevated [CO₂] treatments. Kernels per spike and grain yield showed obvious differences between elevated [CO₂] treatments and CK (p < 0.05).     

Late spring nitrogen applications on wheat on a poorly drained soil

Many of the poorly drained clayey soils of the Mississippi River delta region in Arkansas are used for soft red winter wheat (Triticum aestivum L.) production. Oftentimes, excessive rainfall occurs between the last N application and physiological maturity, resulting in soil conditions conducive to denitrification. Studies were conducted in 1989 and 1990 to evaluate late N applications on five wheat cultivars on a Sharkey silty clay (very fine, montmorillonitic, nonacid, thermic, Vertic Haplaquepts) at Keiser, AR. A linear‐move irrigation system was used to maintain excessive soil moisture conditions throughout the spring growing season to best insure denitrification conditions. After the recommended spring N was applied, N as urea was applied at rates of 0, 34, and 68 kg ha^‐1 at growth stage (GS) 9 in 1989 and GS 10 in 1990. Ammonium nitrate was also evaluated at the 34 kg N ha^‐1 rate. Grain yield, yield components, whole‐plant N concentration, grain N content, and whole‐plant N uptake were evaluated. Grain yield increased each year with late N applications. The optimum N rate was 34 kg ha^‐1 with no difference between the N sources, urea and ammonium nitrate. The yield component accounting for this grain yield increase were kernels per spike in 1989 and kernel weight and kernels per spike in 1990. Whole plant N concentration increased each year and grain N content increased in 1990 with the late N application. The N sources affected N nutrition similarly.     

不同地区大麦种质资源农艺性状分析与评价

为了筛选综合性状优异的大麦种质并探究其主要农艺性状的遗传基础，以57份大麦种质资源为材料，对在张掖、兰州两地的57份大麦种质资源的株高、穗长、穗粒数、总分蘖数、有效分蘖数和千粒重等农艺性状进行鉴定，结果表明，两地区6个性状的平均变异系数为23.08%和26.19%，且张掖地区种植的大麦材料6个农艺性状均优于兰州。通过系统聚类，将参试的57份材料分别分为3个类群，第I类群分别为半矮秆型材料(张掖地区)和中高秆材料(兰州地区)，第II类群和第III类群均为中高秆材料。在主成分分析中，选取累计贡献率为80.072%和75.501%的前3个主成分来评价57份大麦资源。揭示了不同大麦资源的表型特异性。     

生育后期干旱对冬小麦产量和生理特性的影响

盆栽试验的结果表明:后期干旱明显降低冬小麦叶片光合速率和蒸腾速率,并导致保护酶活性下降,MDA累积,叶片衰老加速,硝酸还原酶活性下降,干物质生产受到显著影响。但中度干旱会提高籽粒中酸性转化酶、蔗糖合成酶、碱性转化酶的活性,有利于同化物向籽粒库转运分配;而严重干旱会降低籽粒的代谢活性,不利于同化物向籽粒库转运分配。后期中度干旱对穗粒数、千粒重无影响,对籽粒产量的影响较小,提高了收获指数和水分利用效率。严重干旱显著降低了株高、有效穗数、穗粒数和千粒重,显著降低了产量;同时收获指数和水分利用效率也降低。     

Nitrogen Uptake by Malting Barley Grown under Conditions Found in Buenos Aires Province,Argentina

Abstract

There is a lack of data associated with applications of nitrogen (N) fertilizer to increase yield while not increasing seed protein to levels exceeding those acceptable for malting barley (Hordeum vulgare L.) in the Buenos Aires province of Argentina. The effect of rates and timing of N application on yield and grain N concentration of malting barley was evaluated at eight sites in 1999 and 2000. Aboveground dry matter accumulation and N‐uptake pattern through the growing season were evaluated. Dry matter production and N-uptake were measured at four sampling times: tillering, head emergence, grain filling, and maturity. The N fertilizer increased grain yield, but its response varied between sites. Under appropriate conditions, the yield increased and maintained the grain N concentration within a desirable range for malting barley. Split applications were as effective in increasing grain yield as one addition at emergence, but they invariably increased grain N concentration. The season affected the yield response to N fertilizer and its levels in the grain, but the nitrogen harvest index was not affected by the rate of N application.     

小麦收获指数和其它几个农艺性状的基因效应分析

本利用Ｈａｙｍａｎ的双列杂交法对９个产量性状进行了遗传分析。结果表明：籽粒产量、生物学产量、每穗小穗数和穗长存在上位性效应，收获指数、每穗粒数、株高、千粒重和每穗不孕小数符合加－显遗传模型。株高以加性效应为主，表面为部分显性；收获指数、每穗粒数、千粒重和每穗不孕小穗数以显性效应为主，表面为超显性。多数产量性状的显性基因为增效基因。株高的狭义遗传率最高，其次为收获指数和千粒重。株高在早代选择就有效     

Effect of biochar-amended urea on nitrogen economy of soil for improving the growth and yield of wheat (Triticum Aestivum L.) under field condition

A field experiment was conducted to evaluate effect of biochar-amended urea on nitrogen economy of soil for improving the growth and yield of wheat under field condition. Experiment plan was comprised of twelve treatments with four replications including treatments without application of urea and biochar (control) and urea only. Biochar was applied at 1–10% of the weight of urea fertilizer applied each treatment. Results showed that application of biochar at 10% with recommended dose of urea significantly improved plant height, spike length, number of tillers, number of spikelet per spike, 1000 grain weight, grain yields, biomass yield, harvesting index, nitrogen (N) concentration and uptake in grain and straw, and agronomic efficiency of nitrogen by 6.0%, 11.1%, 32.0%, 55.3%, 5.4%, 38.0%, 19.0%, 9.0%, 19.0%, 26.0%, 65.0%, 50.0%, and 63.0%, respectively, as compared to treatment comprised of recommended rate of nitrogen without biochar.     

施氮对不同种植密度下夏玉米产量及子粒灌浆的影响

以夏玉米杂交种郑单958为材料,在不同种植密度(52500、67500、82500株/hm2)及不同供氮水平(0、120、240、360kg/hm2)下对玉米子粒产量、产量构成、植株地上部干物质积累、子粒灌浆动态及灌浆过程中的物质代谢状况进行了研究。结果表明,不同施氮水平及种植密度下子粒产量的差异主要是由穗粒数所决定。产量及穗粒数的形成与植株地上部干物质积累密切相关,施氮可明显促进植株地上部干物质积累量的增加。穗顶部与中下部子粒的灌浆动态及物质代谢具有明显的不同,授粉后5～20d,顶部子粒灌浆体积、干重、灌浆速率、总可溶性糖、蔗糖、淀粉含量均明显低于中下部子粒;同化物供应的差异是导致顶部与中下部子粒发育差异的一个重要原因。顶部子粒灌浆体积、干重、总糖、淀粉含量施氮处理高于不施氮处理;施氮可明显促进同化物的积累及向顶部子粒的供应,促进顶部子粒灌浆,减少败育,增加有效粒数,提高产量。     

高密植条件下玉米杂交种主要农艺性状与产量的灰色关联度分析

运用灰色关联度分析方法,对高密植条件下14个玉米杂交种的产量与9个农艺性状之间的关系,以及农艺性状之间的关系进行了关联度分析。结果表明,产量与农艺性状的关联度大小依次为穗粒重、百粒重、生育期、穗长、行粒数、穗粗、穗行数、轴粗、秃尖长。在育种工作中,应首先选择单穗粒重、百粒重高的杂交种,在产量相当的情况下生育期短、穗长长、行粒数多的杂交种。     

不同播期冬小麦小花发育特性与同化物代谢的相关性

【目的】推迟播期能够维持单位面积粒数已在前期研究中得到证实,本研究进一步探讨不同播种期冬小麦小花发育特征及分化、退化的差异性,分析植株同化物积累、分配与小花发育和结实的关系,旨在为提高小麦穗粒数以及丰富小麦高产栽培理论提供参考。【方法】试验于2014—2015年和2015—2016年连续两个小麦生长季,在山东省泰安市岱岳区大汶口镇东武村山东农业大学试验田 (35°57′N,117°3′E) 进行,以泰农18和济麦22为试验材料,设置9月24日、10月1日、10月8日、10月15日和10月22日共5个播期处理,观察记载小花发育过程中分化和退化数量动态以及最终结实粒数,测定开花期穗部和茎秆的干物质和氮素积累量,计算小花退化阶段整株和穗部的干物质和氮素积累速率。【结果】播期推迟条件下,单位面积可孕花数和单位面积结实粒数获得了维持,单位面积最大分化小花数明显降低,小花存活率显著提高。推迟播期明显减少了小花退化数量,小花退化速率明显降低。在小花退化阶段,推迟播期加速了整株和穗部的干物质和氮素积累,从而为开花期穗干重的维持以及干重穗茎比和氮素穗茎比的提高提供了保证。相关分析表明,开花期单位面积可孕花数分别与穗干物重、干物重和氮积累量穗茎比、整株和穗的干物质和氮的积累速率以及小花存活率均呈极显著正相关。推迟播期明显减少了有效茎蘖和无效分蘖所产生的退化小花数,尤其无效分蘖产生的退化小花数下降幅度更加明显。提高主茎在群体中同化物所占比例能够有效维持单位面积可孕花数和减少退化小花数,降低了小花死亡消耗。此外,推迟播期提高了可孕花累积生长度日生产效率,降低了退化小花累积生长度日生产效率。【结论】推迟播期明显降低了小花的退化,从而提高了小花存活率,开花期单位面积可孕花数的维持与植株同化物代谢密切相关。适期晚播提高了主茎在群体中的比重,有利于减少无效消耗和提高资源利用效率。     

Grain phosphorus and phytate contents of wheat genotypes released during last 6 decades and categorization of selected genotypes for phosphorus use efficiency

Grain phosphorus (P) and phytate contents are important for early growth and quality of wheat, respectively. We studied seed P and phytate contents of 57 wheat genotypes released during last 6 decades. The grain total P and phytate P concentrations ranged from 2.0 to 8.9 mg g^?1 and 1.6 to 4.7 mg g^?1, respectively. Grain P was higher in genotypes released in current or last decade than pre-green revolution period and it correlated well with grain phytate contents. Indicating that breeders worked only for increased grain P and did not consider the phytate contents. Twenty-five genotypes were selected based on differences in grain P and phytate contents to observe the P use efficiency under field conditions. Genotypes differed significantly for grain P and yield at both 0 and 60 kg ha^?1 P levels. In conclusion, phytate fraction in grains of recent wheat genotypes was more as compared to old genotypes and genotype Inqlab-91 and Chakwal-86 had maximum grain total P. Moreover, number of productive tillers, spikelet per spike, grain weight, harvest index and grain P concentration and uptake were found responsible for P tolerance under P deficiency.     

基于旱地小麦高产优质的氮肥用量优化

  【目的】  探讨长期定位施氮条件下小麦产量与籽粒养分含量的变化,及土壤硝态氮、有效磷和速效钾的变化,为旱地小麦合理施用氮肥,保持土壤肥力,提高产量和改善品质提供理论依据。  【方法】  本研究基于2004年在黄土高原开始的长期定位施肥试验,2015—2017连续3年取样,研究了施氮量对土壤硝态氮、有效磷、速效钾含量,小麦氮磷钾素吸收利用,籽粒氮、磷、钾含量,地上部生物量、籽粒产量及其构成的影响。  【结果】  与不施氮相比,长期施氮小麦平均增产67.1%,生物量提高52.0%,收获指数提高9.5%;穗数和穗粒数平均分别提高32.5%和40.0%,千粒重下降7.1%。施氮量与产量、生物量呈抛物线关系,获得最高产量6587 kg/hm2的施氮量为N 215 kg/hm2。籽粒氮含量随施氮量增加而增加,磷含量降低,钾含量变化较小。土壤硝态氮含量与施氮量呈显著正相关,小麦获得最高产量时播前和成熟期硝态氮含量分别为7.2和10.3 mg/kg;有效磷含量随施氮量增加而降低,速效钾含量变化较小。氮收获指数、生理效率、偏生产力、农学效率均随施氮量增加而降低。  【结论】  综合考虑小麦的籽粒产量和籽粒关键养分含量,研究区域旱地冬小麦产量目标应为6300 kg/hm2,施氮量为N 150 kg/hm2、施磷量为P₂O₅ 100 kg/hm2,播前或收获期表层 (0—20 cm) 土壤硝态氮保持在6.0～8.0 mg/kg、土壤有效磷12.0～15.0 mg/kg、土壤速效钾139～140 mg/kg。     

黄淮地区稻茬小麦超高产群体特征研究

为探讨黄淮地区稻茬小麦超高产(9 000 kg·hm-2)群体的生长发育特性,以该区域推广面积较大的半冬性小麦品种‘连麦6号’、‘济麦22’和‘烟农19’为材料,在试验总结出包括基本苗调控和氮肥运筹等一套适宜黄淮地区稻茬麦超高产栽培技术的基础上,建立稻茬小麦高产和超高产群体,对其系列生育、生理特性以及产量要素进行调查分析。结果表明,与高产小麦群体(产量为7 380~7 889 kg·hm-2)相比,超高产(9 000 kg·hm-2)小麦群体单位面积穗数差异不显著,但穗粒数和千粒重显著增加;超高产小麦抽穗前茎蘖数较高产群体少,但分蘖成穗率较高;超高产群体小麦的叶面积指数,生育前期较高产群体低,抽穗后则显著高于高产群体,两者干物质积累生育前期无明显差异;超高产小麦抽穗期、乳熟期与蜡熟期的根冠比、根系伤流量均显著高于高产群体;超高产小麦粒叶比、茎鞘物质运转率和收获指数均高于高产群体。因此,本文提出了黄淮地区稻茬小麦超高产(9 000 kg·hm-2)群体的产量结构与群体指标:单位面积穗数(700±20)×104·hm-2,每穗实粒数32,千粒重42 g,茎蘖成穗率45%;抽穗期叶面积指数6.5~7.0;成熟期总干重20 700 kg·hm-2,粒叶比14 mg·cm-2;抽穗期根冠比0.28,根系伤流量7.1 g·m-2·h-1;收获指数0.45。     

Yield variability related to landscape properties of a loamy soil in central Belgium

A field was investigated with precision farming techniques to delineate zones with different yield potential due to previous soil erosion. Winter wheat (Triticum aestivum L.) grain yield, straw yield, biomass and harvest index were measured with a combine harvester. Fuzzy clustering of grain and straw yield provided good delineation of zones in the field with different yield potential. Entropy and fuzziness calculations for different number of classes resulted in a division of the field into five clearly differentiated yield potential zones. Straw yield, biomass and harvest index were significantly different among zones. Grain yield was significantly different for all zones, except for two. Elevation and slope of the field were measured from a global positioning system (GPS) unit on the combine. Both were related to yield variability in the field. Average elevation, slope and soil type were calculated per cluster class. High grain yield, straw yield and biomass could be related to flat, high places in the field with little erosion. Good grain yield, low straw yield and high harvest index were found on relatively steep slopes subjected to erosion. High straw yield and low grain yield were found at low places in the field on relatively steep slopes. Lowest grain yield, straw yield and biomass were located on steepest slopes with high erosion and in depressions where accumulation of eroded soil took place and slumping and crusting of the soil were present. This information suggests that variable management on a site-specific basis would optimize yield and inputs.     

Phosphorus seed coating as starter fertilization for spring malting barley

Abstract

Experiments were conducted with malting barley (Hordeum vulgare L.) cultivars in 2003 and 2004 in central, western and southern Lithuania to test phosphorus (P) availability at early seedling growth stage with P seed coating. Phosphorus seed coating resulted in alteration to plant stand structure traits. Despite the fact that seedling emergence sometimes decreased, the number of total and productive stems, number of grains per ear and 1000-grain weight increased. The positive effect of P seed coating on grain yield was revealed when the growth conditions during post-anthesis were favourable for exploiting the potential that was obtained during the pre-anthesis phase. In our experiment favourable conditions were considered those that generated a grain yield over 6 t ha^?1. According to path coefficients analyses the significant positive effect of P seed coating on malting barley yield increase was related to seed weight increase. Although P seed coating slightly increased single grain N concentration and thus grain protein concentration, grain protein concentration ranged from 8.6% to 10.2% and met the quality standard requirements for malting barley in all trials and treatments.     

Genotypic Differences in Dry Bean Yield and Yield Components as Influenced by Nitrogen Fertilization and Rhizobia

Dry bean (Phaseolus vulgaris L.) is an important legume worldwide and nitrogen (N) is most yield limiting nutrients. A field experiment was conducted for two consecutive years to evaluate response of 15 dry bean genotypes to nitrogen and rhizobial inoculation. The N and rhizobia treatments were (i) control (0 kg N ha^?1), (ii) seed inoculation with rhizobia strains, (iii) seed inoculation with rhizobia strains + 50 kg N ha^?1, and (iv) 120 kg N ha^?1. Straw yield, grain yield, and yield components were significantly influenced by N and rhizobial treatments. Grain yield, straw yield, number of pods m^?2, and grain harvest index were significantly influenced by year, nitrogen + rhizobium, and genotype treatments. Year × Nitrogen + rhizobium × genotype interactions were also significant for these traits. Hence, these traits varied among genotypes with the variation in year and nitrogen + rhizobium treatments. Inoculation with rhizobium alone did not produce maximum yield and fertilizer N is required in combination with inoculation. Based on grain yield efficiency index, genotypes were classified as efficient, moderately efficient, and inefficient in nitrogen use efficiency (NUE). NUE defined as grain produced per unit N applied decreased with increasing N rate. Overall, NUE was 23.17 kg grain yield kg^?1 N applied at 50 kg N ha^?1 and 13.33 kg grain per kg N applied at 120 kg N ha^?1.     

施氮量对不同品质类型小麦产量、品质和旗叶光合作用的调节效应

采取田间试验,研究了施氮量对强筋小麦临优145和中筋小麦临优2018产量、品质、灌浆进程及旗叶光合作用的影响。结果表明,施氮使成穗数、穗粒数和结实小穗增加,千粒重降低,产量提高,以成穗数对产量贡献最大;施氮使平均灌浆速率降低,灌浆持续时间延长,灌浆后期灌浆速率下降相对较慢;旗叶叶绿素相对含量和净光合速率提高。临优145施氮量225.kg/hm2和临优2018施氮量150.kg/hm2时,2个品种的营养品质和加工品质均得到改善,蛋白质各组分均有所提高,达到产量与品质的协调。综合考虑施氮对2个不同品质类型小麦产量和品质的影响,施氮量对成穗数、穗粒数和产量影响作用大,千粒重和品质主要决定于品种遗传特性。