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1.
中国西南丘陵旱地气候冬干春旱且速效磷缺乏,是冬小麦生产的主要限制因素。为明确秸秆覆盖与施磷对西南丘陵旱地小麦小花发育与结实特性的影响,以川麦104为供试材料,采用裂区设计,主区为玉米秸秆覆盖(SM)和不覆盖(NSM),裂区为0、75和120 kg P2O5·hm-23个施磷水平,比较分析了不同处理下小麦小花分化及结实特性的差异。结果表明,秸秆覆盖与施磷均可提高小麦小花分化数和可孕小花数,且磷素效应大于秸秆覆盖效应。与不施磷相比,施磷75和120 kg·hm-2条件下最大分化小花数分别增加了17.4%和78.0%,可孕小花数分别增加27.0%和94.1%,小花存活率提高了16.5个百分点。施磷后穗基部可孕小花数和结实粒数增幅较大,穗中部和顶部增幅较小。与不施磷相比,施磷75和120 kg·hm-2条件下,穗基部可孕小花数均极显著增加,增幅分别为100.0%和127.2%;结实粒数显著增加,增幅分别为186.4%和193.2%。秸秆覆盖后产量较不覆盖提高20.5%;施磷75和120...  相似文献   

2.
《Plant Production Science》2013,16(2):189-198
Abstract

Grain number per spike of wheat is lower in early sowing than in the conventional standard cultivation in Yamaguchi, Prefecture, Japan. Components of the grain number per spike in five cultivars were analyzed with respect to temperature during the spike development period throughout three growing seasons 2001/2002, 2002/2003 and 2003/2004 to find the cause of the problem of early sowing cultivation. The plants sown in early-October and late-November were called the early sown group and the standard group, respectively, in the following. Three of the five cultivars, Hokushin, Akitakko and Nanbukomugi, showed a strong winter habit, which requires very cold temperatures for spike differentiation. The other two cultivars, Iwainodaichi and Airakomugi, had a moderate winter habit. Grain number per spike and grain yield were decreased by early-sowing (compare with the standard group) in almost all cultivars throughout the three growing seasons. The three cultivars which had a strong winter habit had fewer spikelets per spike in the early-sown group than in the standard group. The other two cultivars which had a moderate winter habit had fewer grains per spikelet in the early-sown group. The higher the temperature during the spikelet formation phase, which is from flag leaf initiation to terminal spikelet initiation, the higher the number of spikelets per spike in the standard group. The spikelet number per spike in the early-sown group increased with the increase in productive tillers under fertile conditions. Such conditions also increased the grain number per spike.  相似文献   

3.
冬、春性小麦品种早播(9月30日)、适播(10月30日)的总小花数、可孕小花数及结实粒数均极显著高于晚播(3月2日)。晚播对春性品种小花分化发育与结实的不利影响小于冬性品种。穗粒数的多少与可孕小花数及其结实率密切相关,而与总小花数及其结实率无明显联系;同时大穗多粒基因型也以较高的可孕小花结实率为生理基础。孕穗期小花数均与叶面积、叶片重、叶鞘重和总干物重呈显著或极显著正相关,而与茎高的相关不显著。此外,冬、春性品种的结实粒数均与成熟期茎叶重、总单茎重、结实小穗数、穗长和穗粒重之间呈极显著正相关,表明良好、协调的营养生长与生殖生长的关系是改善小花发育质量、提高穗粒数的根本保证。  相似文献   

4.
《Plant Production Science》2013,16(4):283-290
Abstract

The spike of the main culm in winter wheat was examined by scanning electron microscopy from the double ridge to 6 days after the terminal spikelet stage to quantitatively evaluate the effects of shading and nitrogen supply at the spikelet phase on the numbers of spikelets and floret primordia, and the development of florets. Positional differences on a spike in grain setting at maturity were also investigated. Nitrogen supply affected neither the rate nor duration of spikelet initiation, the number of spikelets remaining unchanged. Although nitrogen supply positively affected the initiation and development of florets, it slightly reduced the grain weight per spike at maturity due to a decrease in the number of grains per spike and the reduced grain weight. These results suggested that under the field condition, nitrogen supply at the double ridge stage is too late to have a significant effect on the spikelet number, and might induce competition for nitrogen between the main culm and tillers, or induce mutual shading between plants, resulting in lighter grain weight per spike. Shading decreased the rate of spikelet initiation, resulting in a significant decrease in spikelet number. The initiation and the development of florets were also decreased by shading. Lower non -structural carbohydrate content at the terminal spikelet stage suggested that the limited assimilate supply by shading was likely responsible for the decreases in the initiation and development of spikelets and florets.  相似文献   

5.
Water and nitrogen (N) availability are the main factors influencing crop growth globally. Poorly distributed or insufficient water for crop growth requirements decreases yields in drought-prone areas such as those with a Mediterranean type environment. Cereal grain yield is a complex trait of interrelated components: plants per unit land area, spikes per plant, spikelets per spike, grains per spikelet, and single grain weight (SGW). The effect of water limitation and timing on development of yield components was studied in detail at the spike level in spring wheat (Triticum aestivum L.) cultivar Amaretto. An experiment with three watering treatments (control watering, CONT; drought prior to pollination, DR1 and terminal drought, DR2) was arranged in a large greenhouse (20 m × 30 m), with the use of standard field-trial machinery. Automated blackout curtains were used to control day length, which was set to correspond to that at 40°N. With watering treatments, two N application rates (60 and 120 kg N ha−1) were used to investigate the N effect and potential watering × N interaction on yield formation and realisation. The water deficit effect exceeded the effect of N on fertile floret and grain number and SGW. DR1 strongly reduced the number of fertile florets and grains, whereas terminal drought reduced the number of grains per spike. Resuming the watering at pollination markedly enhanced photosynthesis, and hence grain filling capacity, resulting in the highest SGW in DR1. Enhancement in availability of key resources was associated with reduced rate of fertile floret and grain abortion, which resulted in higher grain to fertile floret ratio in DR1. Spikelets in the mid-section of the spike dominated yield formation in all treatments. In DR1 this was especially emphasised as 53% of the grain yield was produced in spikelets 4–6, whereas in DR2 and CONT this was 45 and 41%, respectively. Grains in proximal position in the spikelets produced about 80% of the spike grain yield, the proportion being slightly higher in stressed plants and plants receiving 60 kg N. No marked N × water deficit treatment interaction occurred for any of the measured parameters.  相似文献   

6.
为了研究紫外线辐射对作物生长发育的影响,采用人工增加紫外线辐射的方法,研究了紫外线强度(UV-B)增加对小麦节间大维管束条数及穗部性状的影响,并分析了UV-B增加条件下,小麦节间大维管束条数与穗部性状的相关关系。结果表明:UV—B增加则每穗粒数显著减少,主要是由于每穗小穗数和每小穗小花数减少,而结实率无显著变化,同时UV-B增加小麦穗颈节间大雄管束条数也显著减少.穗下第二节间与穗颈节间大维管束条数百分率显著下降.在UV-B增加条件下,每穗小穗数和每穗粒教与穗颈节的节间大维管束条数呈极显著正相关.因此我们认为UV-B增加导致小麦节间大维管束条数的减少是每穗粒数下降的重要原因之一。  相似文献   

7.
为了解小麦小花发育成粒特性与同化物分配间的关系,以大穗型品种周麦16和多穗型品种豫麦49-198为材料,分析了两种穗型小麦小花发育成粒特性及同化物分配的差异。结果表明,周麦16的小花退化、败育速率较豫麦49-198缓慢,且在小穗结实率、小花结实率和可孕小花结实率上均高于后者。在小花发育中后期,大穗型品种周麦16转移到穗部的同化物比多穗型品种豫麦49-198多。经相关分析,花期完善小花(有完整绿色花药的小花)数与穗干重、穗氮积累量、茎干重、茎氮积累量呈微弱的正相关,与穗茎干重比、穗茎氮积累量比呈显著正相关,与穗干重/穗氮积累量比呈极显著正相关。周麦16的穗茎干重比、穗茎氮积累量比显著高于豫麦49-198,二指标均与穗干重/穗氮积累量比呈极显著正相关。进一步分析发现,周麦16的开花期单位面积完善小花数与成熟期单位面积粒数分别较豫麦49-198增加3.85%和4.65%,且品种间差异均达到极显著水平。  相似文献   

8.
The objective of this study was to identify physiological processes that result in genotypic and N fertilization effects on rice yield response to elevated atmospheric CO2 concentrations ([CO2]). This study conducted growth and yield simulations for 9 rice genotypes grown at 4 climatically different sites in Asia, assuming the current atmospheric [CO2] (360 ppm) and elevated [CO2] (700 ppm) using 5 levels of N fertilizer (4, 8, 12, 16, 20 g m−2 N fertilizer). A rice growth model that was developed and already validated for 9 different genotypes grown under 7 sites in Asia was used for the simulation, integrating additional components into the model to explain the direct effect of [CO2] on several physiological processes. The model predicted that the relative yield response to elevated [CO2] (RY, the ratio of yield under 700 ppm [CO2] to that under 360 ppm [CO2]) increased with increasing N fertilizer, ranging from 1.12 at 4 g m−2 N fertilizer to 1.22 at 20 g m−2 N fertilizer, averaged overall genotypes and locations. The model also predicted a large genotypic variation in RY at the 20 g N treatment, ranging from 1.08 for ‘WAB450-I-B-P-38-HB’ to 1.41 for ‘Takanari’ averaged overall locations. Combining all genotypes grown at the 5N fertilization conditions, a close 1:1 relationship was predicted between RY and the relative [CO2] response in spikelet number for crops with a small number of spikelets (less than 30,000 m−2) under the current atmospheric [CO2] (n = 18, r = 0.89***). In contrast, crops with a large number of spikelets under the current atmospheric [CO2] showed a significantly larger RY than the relative [CO2] response for spikelet number per unit area. The model predicted that crops with a larger number of spikelets under the current atmospheric [CO2] derived great benefit from elevated [CO2] by directly allocating increased carbohydrate to their large, vacant sink, whereas crops with a smaller number of spikelets primarily required an increased spikelet number to use the increased carbohydrate to fill grains. The simulation analyses suggested that rice with a larger sink capacity relative to source availability under the current atmospheric [CO2] showed a larger yield response to elevated [CO2], irrespective of whether genotype or N availability was the major factor for the large sink capacity under the current [CO2]. The model predicted that the RY response to nitrogen was brought about through the N effects on spikelet number and non-structural carbohydrate accumulation. The genotypic variation in RY was related to differences in spikelet differentiation efficiency per unit plant N content. Further model validation about the effects of [CO2] on growth processes is required to confirm these findings considering data from experimental studies.  相似文献   

9.
施氮量对小麦穗花发育及穗粒数的影响   总被引:2,自引:0,他引:2  
为了解小麦穗发育与氮素营养的关系,通过田间试验,设置90、180、270kg·hm-2三个施氮量水平(分别用N1、N2和N3表示),选用半冬性小麦品种豫麦49和弱春性品种太空6号为材料,研究了施氮量对小麦主茎幼穗长度、第九小穗小花发育进程、每穗总小穗数、不孕小穗数、小穗结实率、产量及其构成的影响。结果表明,随着时间的推移,小麦主茎幼穗长度对施氮量响应逐渐明显,豫麦49和太空6号分别表现为N3N2N1和N2N3N1。豫麦49第九小穗第4~6朵小花发育进程对施氮量响应差异显著,且分化程度随施氮水平的提高而增加;太空6号第3~6朵小花进程对施氮量响应差异显著,其中第3朵小花在发育进程前期N2处理快于N1、N3处理,中期和后期N2、N3处理快于N1处理,第4~6朵小花分化程度则一直表现为N2N3N1。不同施氮处理间总小穗数、不孕小穗数、小穗结实率、产量、穗粒数等指标差异亦显著,且品种之间对施氮反应存在差异,其中豫麦49的总小穗数、小穗结实率、产量、穗粒数呈N3N2N1,而太空6号呈N2N3N1;豫麦49小穗结实率呈N3N2N1,而太空6号呈N2N3N1。由此可见,施氮量对小麦产量的影响与其对小穗中部小花发育、每穗总小穗数、不孕小穗数和单穗结实率的影响相一致。  相似文献   

10.
为了明确种植密度对冬小麦结实特性和产量的影响,于2020-2021年以大穗型品种衡观35和多穗型品种济麦22为试验材料,设置4个种植密度水平,分别为每公顷基本苗180万(D180)、300万(D300)、420万(D420)和540万(D540)株,比较分析了不同种植密度下冬小麦小花结实、籽粒空间分布特征和产量的差异。结果表明,随着种植密度的降低,衡观35主茎穗上部和I分蘖穗下部、济麦22主茎和I分蘖穗中上部小穗位的结实粒数呈增加的趋势。降低种植密度促进了两个品种穗中部小穗位弱势小花、上部和下部小穗位强势小花的结实。衡观35主茎穗中上部和I分蘖穗中部小穗位的结实粒数均高于济麦22。开花期穗干重与可孕小花数呈显著正相关。低种植密度处理下开花期穗干重的增加为其获得较高的穗粒数奠定了良好的物质基础。种植密度对千粒重影响不显著,但显著降低了衡观35的穗数。由于产量构成三要素的协调作用,两个品种均在D300处理下获得了最高产量,但与其余种植密度处理间差异均不显著。综合来看,在保证穗数的前提下,适当降低种植密度会促进冬小麦主茎和分蘖穗结实,进而增加穗粒数和产量,可节约生产成本,有利于冬小麦绿色高产高效生产。  相似文献   

11.
Success in “super” rice breeding has been considered a great progress in rice production in China. This study aimed to test the hypothesis that an improved root system may contribute to better shoot growth and consequently to higher grain yield in “super” rice. Two “super” rice varieties Liangyoupeijiu (an indica hybrid) and Huaidao 9 (a japonica inbred) and two elite check varieties Yangdao 6 (an indica inbred) and Yangfujiang 8 (a japonica inbred) were field-grown at Yangzhou, China in 2006 and 2007. Root and shoot dry weight (DW) was significantly greater in “super” rice varieties than in check ones throughout the growth season in both years, so was the root length density. Root oxidation activity (ROA) and root zeatin (Z) zeatin riboside (ZR) content, in per plant basis, were significantly greater in “super” rice than check varieties before and at heading time. However, both ROA and root Z + ZR content, either in per plant basis or per unit root DW basis, were significantly lower in ‘super’ rice than in check varieties at the mid- and late grain filling stages. Grain yield of the two ‘super’ rice varieties, on average, was 10.2 t ha−1 in 2006 and 11.4 t ha−1 in 2007, and was 13% and 21% higher than that of check varieties, respectively. The high grain yield was mainly due to a larger sink size (total number of spikelets) as a result of a larger panicle. The percentage of filled grains of the two “super” rice varieties, on average, was 72.9% in 2006 and 79.0% in 2007, and was 19.4% and 12.9%, respectively, lower than that of the check varieties. The mean ROA and root Z + ZR content during the grain filling period significantly correlated with the percentage of filled grains. Collectively, the data suggest that an improved root and shoot growth, as showing a larger root and shoot biomass and greater root length density during the whole growing season and higher ROA and root Z + ZR content per plant at early and mid-growth stages, contributes to the large sink size and high grain yield in the “super” rice varieties. The data also suggest the yield of “super” rice varieties can be further increased by an increase in filled grains through enhancing root activity during grain filling.  相似文献   

12.
为了解燕麦穗粒数形成过程与源、库特征之间的关系,连续两年以10个不同来源、熟期、穗型、株型、小穗数的燕麦品种为试验材料,测定三叶期至拔节期的幼穗分化阶段及抽穗期源库特征,采用方差分析、聚类分析、逐步回归分析等方法,分析不同燕麦基因型源库特征及对穗粒数形成过程的影响。结果表明,燕麦穗粒数形成过程存在基因型差异,幼穗分化较好品种的穗粒数较全部品种平均值高11.22%~65.43%;幼穗分化较好品种的光合势、干物质量、粒数叶比、收获指数显著高于幼穗分化较差品种,其中粒数叶比和收获指数是影响穗粒数形成的主要因素,粒数叶比和收获指数较全部品种平均值分别高0.99%~68.74%和0.85%~13.80%。综上所述,源库协调是燕麦幼穗分化良好的生理基础,可通过提高光合势和干物质量达到增源的目的,进而提高穗粒数。  相似文献   

13.
Abstract

The number of grains per spikelet and the number of spikelets per spike are important factors that influence grain yield in wheat. Three wheat genotypes in four foreign groups (OA, OC, OH and OJ) differing in spike type and Japanese cultivars (cvs) were grown under various combinations of seeding densities and fertilization levels. In all groups, the spikelet number per spike and the spike length at maturity were highest at low seeding densities and high levels of fertilization. The OA group (Nepal) and Haruyutaka (Japanese cv) gave a weak response in spikelet number per spike, while the OJ group (Xinjiang Uygur, China) gave a weak response in spike length. The OC group (except for T6), the OH group (Tibet) and Japanese cvs (except for Haruyutaka) responded to treatments in both spikelet number per spike and spike length. The T6 genotype in the OC group (Nepal) gave a weak response in both spikelet number per spike and spike length. Although the OA group had the longest spikes and the OJ group had the shortest spikes, there was no difference in the duration of spike elongation between the OA group and the OJ group. Spike length appeared to be determined mainly by the rate of spike elongation and was not restricted by the dry weight of the spike during the growth phase of the spike.  相似文献   

14.
The critical period for yield determination in barley (Hordeum vulgare L.) is situated in the pre-heading phases. During the latest part of the critical period one of the most important yield components (i.e. the number of grains per spike) is set in two- and six-rowed barley. In wheat, much is known about the role of the spike in assimilate acquisition for the establishment of grains per spike, but not in barley. This paper evaluates how biomass partitioning between vegetative and reproductive organs impacts floret development and primordia survival in response to radiation during different periods in the crop cycle, in barley lines. Field experiments were carried out using two- and six-rowed near isogenic barley lines differing only in spike type. Shading treatments were applied at different periods during the crop cycle (from 60 to 15 days before and after heading) reducing the intercepted radiation (ca. 70%). Dynamics of floret primordia initiation and mortality and of floret development for different spikelet positions along the spike were measured, and biomass partitioning between vegetative and reproductive structures was calculated.

Pre-heading shading reduced fertile florets per spike (P < 0.001). In the immediate pre-heading treatment, distal floret primordia could not reach a fertile floret stage due to a low rate of floral development.

The amount of assimilates partitioned to the spike at heading affected the number of fertile florets per spike in both barley types. However, when spike biomass at heading was corrected by nitrogen concentration, the fitness of the relationship did not improve in relation to the first one. In relative terms, radiation restrictions during the immediate pre-heading phase increased the amount of biomass partitioned to the growing spike.  相似文献   


15.
安徽沿淮和淮北地区小麦穗粒重研究   总被引:2,自引:0,他引:2  
为给重穗型小麦新品种选育及高产育种提供参考依据,以24个小麦品种(系)为材料,对穗粒重与产量、产量三要素及其他18个性状间的关系进行了分析。结果表明,供试品种间穗粒重、收获指数、产量及产量三要素存在着极显著差异;穗粒重与产量呈显著正相关,与穗粒数、收获指数、单茎生物产量、单茎草重呈极显著正相关,与倒三叶的面积呈显著正相关,与穗数、籽粒容重呈极显著负相关。根据穗粒重把小麦品种划分为三大类:重穗型,穗粒重≥1.8g;中穗型,穗粒重为1.4~1.8g;轻穗型,穗粒重≤1.4g。沿淮和淮北地区可通过着重提高穗粒数、同步提高单茎生物产量与收获指数的途径提高穗粒重。  相似文献   

16.
为了明确不同种植密度下小麦主要性状与产量和蛋白质含量的关系,以4种种植密度下4个小麦新品系(种)的11个性状为指标,运用灰色关联度分析其主要性状对产量和蛋白质含量构成的影响.结果表明,在不同密度下各主要性状对产量的关联度从大到小依次是:穗长>可孕小稳数>穗下节长>株高>蛋白质舍量>整齐度>不孕小穗数>成穗数>穗重>千粒重>穗颈长.在不同的密度下各主要性状对蛋白质含量的关联度从大到小依次是:株高>可孕小穗数>穗重>千粒重>穗长>整齐度>产量>穗下节长>不孕小穗数>成穗数>穗颈长.表明不同种植密度下影响产量和蛋白质含量的主要性状各有侧重,在高产优质新品种选育中应重视可孕小穗数和株高这两个主要性状.  相似文献   

17.
为了解温光敏核不育小麦不同播期及不同蘖位、花位的育性变化,通过多年分期播种试验,研究了小麦温光敏细胞核雄性不育系C338S不同播期下的育性表现及不同蘖位和花位的育性差异。结果表明,随着播期的调整,C338S分别表现完全不育、高度不育、半不育、低不育、可育的不同育性状态,具有育性转换特性。主茎穗与分蘖穗之间、主茎穗不同部位的小穗之间以及不同位次的小花之间的育性存在差异。发育较晚的后生分蘖的育性高于主茎穗和早生分蘖;主茎穗的下部小穗育性>中部小穗>上部小穗;早播不育植株发育较晚的3、4位小花的育性较好,而晚播可育植株发育较早的1、2位小花的育性较高。  相似文献   

18.
超高产冬小麦四种微量元素的积累及其与产量性状的关系   总被引:1,自引:0,他引:1  
为了明确超高产冬小麦锰、锌、铜、硼的吸收积累特点及与产量相关性状的关系,于2005-2006年冬小麦成熟期测定了不同小麦品种产量相关性状及植株和籽粒中锰、锌、铜、硼的含量与积累量。结果表明,成熟期不同冬小麦品种植株和籽粒中4种元素的含量和积累量存在不同程度的差异,但都表现为锰>锌>铜>硼。植株锰积累量与穗粒数呈显著正相关,植株锰含量和积累量与单株成穗数呈显著负相关。植株和籽粒锌含量和积累量与每穗小穗数、结实小穗数和穗粒数呈正相关,与不孕小穗数呈负相关,但相关均未达到显著水平。植株铜含量与每穗小穂数、结实小穗数、穗粒数和产量均为正相关,且相关达到显著或极显著水平。植株铜积累量与总小穗数、结实小穗数呈显著正相关,与不孕小穗数呈显著负相关。植株硼积累量与产量达到显著正相关水平。综合分析可知,4种微量元素在增加产量和优化产量构成因素中起着不同的作用,在小麦生产中应针对具体的限制因素确定不同微量元素肥料的施用技术。  相似文献   

19.
为探究C、N供给时期和供给水平对小麦籽粒建成及蛋白质含量的影响,以冬小麦品种济麦22为材料,采用离体穗培养的方法,设置了三个蔗糖浓度(C1:20 g·L-1;C2:40 g·L-1;C3:80 g·L-1)和四个硝酸铵水平(N1:0.57g·L-1;N2:1.14g·L-1;N3:2.28 g·L-1;N4:4.56g...  相似文献   

20.
This paper applies linear mixed model and pattern analyses to 122 on-farm trials of commercial and near-commercial sunflower (Helianthus annuus L.) hybrids grown over 15 years in 32 locations of central Argentina to determine the contributions of change in characteristics of germplasm pools to increases in oil yield. The ‘Relative Peak Performance’ (best linear unbiased predictors, BLUPs) of 49 hybrids released for the conventional market between 1983 and 2005 showed genetic gains of 11.9 kg ha−1 year−1, 0.19% year−1 and 16.1 kg ha−1 year−1 for oil yield, grain-oil concentration and grain yield, respectively. Oil yield improvement was consistent across three market segments and a biplot of genotype-by-attribute BLUPs summarised 20 years of breeding to demonstrate how the merging of two germplasm pools of differing maturity, achene type and grain-oil concentration resulted in step-wise improvements in grain yield and grain-oil concentration and a move toward an intermediate maturity. The analysis of general combining ability within a breeding program shows that the female and male germplasm pools were improved in different ways over time. On the female side, much of this improvement was to encompass different combinations of the determining traits of oil yield, while on the male side the improvement was more linear in terms of exploitation of genotypic variance for oil yield per se.  相似文献   

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