共查询到18条相似文献，搜索用时 109 毫秒
1.
遮荫对夏玉米产量和品质的影响 总被引：12，自引：2，他引：10
研究在夏玉米不同生育时期遮荫对产量和品质的影响。结果表明：不同时期遮荫都显著降低玉米子粒产量,花粒期遮荫对玉米子粒产量影响最显著,农大108遮荫50%和90%的分别减产67.5%和79.4%,花粒期遮荫主要降低了千粒重;其次是穗期遮荫,农大108遮荫50%和90%的分别减产34.1%和55.3%,穗期遮荫主要减少了穗粒数;苗期遮荫对其影响相对较小,农大108遮荫50%减产16.9%。玉米子粒产量随着光照强度的减小而显著降低,不同时期遮荫对玉米子粒产量的影响显著大于不同遮荫程度(光照强度)的影响。苗期遮荫对玉米子粒品质没有显著影响;穗期和花粒期遮荫玉米子粒的粗蛋白和赖氨酸含量显著升高,粗脂肪、淀粉含量显著降低。随着光照强度的减小,对子粒品质的影响加剧。不同时期遮荫对玉米子粒品质的影响显著地大于不同遮荫程度的影响。 相似文献
2.
玉米遮荫胁迫研究进展 总被引：6，自引：3，他引：3
遮荫是对玉米生长期间持续阴天寡照的一种模拟,可明显改变玉米的生长环境,限制营养器官和生殖器官发育。遮荫造成叶片出生速度延缓,比叶面积增加,光合性能变差,光合生产能力降低,使雌穗数目减少,雄花退化,雌雄间隔期拉长,结实性下降甚至出现空株。根据近年来国内外玉米遮荫的研究成果,分析遮荫胁迫对玉米形态、生长发育、光合作用、生理特性及产量的影响,探讨玉米遮荫研究方面存在的问题及今后的研究方向。 相似文献
3.
4.
在大田条件下,研究耐密型玉米品种中单909和非耐密型玉米品种丹玉405穗期不同遮荫条件下(S0,自然光照;S1,遮荫44%;S2,遮荫66%)玉米茎秆抗倒伏能力与产量的关系。结果表明,穗期遮荫后,两种类型玉米品种株高和穗位高升高;茎基部茎节单位长度、干重、穿刺强度、压碎强度、折断力度、产量和穗粒数均随遮荫程度的增加而减小,且非耐密型玉米品种下降幅度大于耐密型玉米品种。随弱光胁迫程度的增加,非耐密型玉米品种倒伏率明显高于耐密型玉米品种,非耐密型玉米品种较耐密型玉米品种对弱光反应敏感,千粒重和结实率下降是导致非耐密型玉米品种产量大幅降低的重要原因。 相似文献
5.
6.
7.
以41个玉米自交系为材料,采用大田试验方法,在植株形态建成期设置15%遮荫和不遮荫两种处理方式,研究不同处理下玉米自交系植株形态、物质生产、产量等11个指标以及各指标耐荫系数的变化,并对自交系的耐荫性进行评价。结果表明,遮荫不仅会增加玉米自交系的株高和穗位高,延缓生育进程,而且会降低植株叶面积指数及叶绿素含量,最终影响玉米物质积累及产量的提升。进一步对各指标的耐荫性进行数学统计分析,表明茎干物质、叶面积指数和产量的耐荫系数可作为评价玉米自交系耐荫性指标。筛选出M173、豫82、DH382、618B、P6874、昌7-2、8612A、M753、ZY608、豫1122、PH6WC和M109高度耐荫型玉米自交系;ZY602、ZY606、658、HT60、ZY601、C70、外引-2、四-144、KW7M14、NS501和PH4CV是弱光敏感型玉米自交系。 相似文献
8.
苗期遮荫对大豆茎秆形态和物质积累的影响 总被引：4，自引：0，他引：4
麦/玉/豆套作模式下,玉米的株型直接关系着低层大豆前期生长的荫蔽程度.采用室外盆栽模拟试验,设置遮荫35%、45%、55%三个处理,以不遮荫为对照,研究了苗期不同遮荫程度对大豆茎秆形态和物质积累的影响.结果表明,遮荫35%可能是贡选1号盆栽条件下茎正常生长的临界光强.苗期遮荫程度越大,干物质在茎中的积累速率越快,向茎中的分配比例越大,但基部节间(子叶节、基部第一节、基部第二节)单位干重增长越慢.V9期恢复自然光照后,苗期遮荫的影响逐渐减弱,干物质在茎中的积累速率及在茎中的分配比例、基部节间单位干重增长速率均逐渐恢复到对照水平,且子叶节、第一节单位干重的增长在R4～R6期出现补偿效应.在苗期遮荫条件下,茎粗、茎干重、茎(主茎、基部节间)单位干重、主茎纤维素含量与倒伏率显著负相关,主茎木质素含量与倒伏率极显著负相关.可见,苗期遮荫显著影响了大豆茎秆的形态发育和物质积累,荫蔽程度小,大豆茎秆发育良好,不易倒伏.在实际生产中,应选择株型较为紧凑的玉米品种,以减缓大豆生长过程中的弱光胁迫. 相似文献
9.
采用大田试验方法，在大喇叭口期对渍水条件下的36个玉米自交系玉米进行50%遮荫和不遮荫处理，研究遮荫胁迫对自交系农艺性状及干物质积累的影响，对自交系的耐阴性进行评价。结果表明，渍水条件下的玉米自交系遮荫后雌雄间隔期延长，穗位叶叶绿素含量显著增加，地上部干物质显著减少，16个自交系的雄穗主轴长度显著降低，大部分自交系的雄穗分支数无显著变化，株高、穗位高变化不一致。雌雄间隔期延长天数与地上部干物质量减少的百分率呈极显著相关。以雌雄间隔期延长天数与地上部干物质量减少的百分率为主要指标，筛选出11个耐阴性强且具有一定耐涝性的自交系LH01、LH04、LH14、LH17、LH21、LH23、LH24、LH27、LH28、LH32、LH33，可作为豫中南阴雨寡照地区的基础育种材料。 相似文献
10.
以容易发生空秆和不容易空秆的成对近等基因系、易发生空秆的杂交种、正常杂交种、自交系为试材,采用人工遮荫方法进行光照胁迫,对诱发空秆的光照因子及其胁迫效果进行研究。结果表明,试验初步验证了玉米存在遗传缺陷性空秆现象,弱光胁迫对不同品种均会造成空秆并随着遮荫强度增大而增加,品种间差异很大。抽雄期至吐丝末期是玉米空秆对弱光胁迫的最敏感时期,雌穗不能正常吐丝是造成品种异常性高比率空秆的主因,结穗率降低是次要原因。易空秆近等基因系沈农98A空秆的光胁迫强度应在遮荫38%以下;不空秆近等基因系沈农98B与正常自交系昌7-2的耐荫性相近,诱发其空秆的光胁迫强度范围应在遮荫38%~60%之间;在遮荫75%左右时,东单90、东单80与郑单958之间,空秆率有明显区别。 相似文献
11.
采用人工模拟荫湿环境,比较不同基因型玉米在荫湿环境与自然环境条件下穗位叶面积及其叶绿素含量的差异。结果表明,荫湿环境对玉米穗位叶面积、叶绿素及其组分含量具有明显影响,穗位叶面积及其叶绿素a/b值均呈下降趋势,叶绿素相对含量和叶绿素b含量呈明显上升趋势,这些性状的变化基因型间存在显著或极显著差异。用穗位叶面积及其叶绿素含量计算出18个杂交种的综合耐荫湿系数平均值为0.751 1,标准差为0.178 5,变异系数为23.76%;30个自交系的综合耐荫湿系数平均值为0.678 1,标准差为0.155 4,变异系数为22.91%。根据综合耐荫湿系数,采用t检验选出耐荫湿性强的杂交种有8个,自交系有12个;耐荫湿性中的杂交种有5个,自交系有9个;耐荫湿性弱的杂交种有5个,自交系有9个。 相似文献
12.
Responses to shade and subsequent recovery of soya bean in maize-soya bean relay strip intercropping
Yushan Wu Wanzhuo Gong Feng Yang Xiaochun Wang Taiwen Yong 《Plant Production Science》2016,19(2):206-214
In relay intercropping systems, late-planted crops often grow under the shade of the canopy of early-planted tall crops and then transfer to full sunlight after the harvest of the early-planted crops. In order to know the effects of recovery growth of the late-planted soya bean in maize–soya bean relay intercropping, a field experiment was carried out to observe architectural, morphological, physiological and anatomical traits of soya bean plants related to shade and subsequent removal in intercropping before and after maize harvest, respectively. During shade period, soya bean biomass was severely reduced, and stem elongation was stimulated. Typical features of shade grown leaves were found, such as lower LMA (leaf mass per unit area), thinner thickness, higher chlorophyll content, lower chlorophyll a:b ratio. Whole-plant leaf area analysis found that soya bean increased leaf area ratio by adjusting leaf morphology rather than by dry mass allocation. After maize harvest, leaf area and leaf mass increased rapidly, contributing to compensation growth in intercropped soya bean. Meanwhile, physiological and anatomical traits of leaf went back to similar levels as grown in sole cropping. However, stem morphological traits were irreversible after removal of shade. Finally, no difference on seed weight per plant of soya bean was observed between relay intercropping and sole cropping. Based on these findings, we speculated the recovery growth might be the direct determining factor on pod formation in soya bean, and improvement on the capacity of recovery growth could increase yield of relay intercropped soya bean. 相似文献
13.
不同耐阴性玉米雌穗幼穗分化对遮荫胁迫的反应差异 总被引：1，自引：1，他引：0
以易空秆和不易空秆的成对近等基因系沈农98A、沈农98B和易发生空秆的玉米杂交种D90、不易发生空秆的品种郑单958为试材,在田间种植条件下,通过人工遮荫方法进行不同强度的光照胁迫处理,研究不同耐阴性材料雌穗幼穗分化对光胁迫的反应差异。结果表明,不同耐阴性材料在遮荫胁迫下雌穗幼穗发育均受到很大影响,但不同耐阴性材料之间差异很大。易空秆的杂交种及自交系在轻度胁迫下,D90幼穗长度减少38.2%,结穗率减少17.0个百分点;沈农98A幼穗长度减少35.8%,结穗率降低78.7个百分点。与杂交种相比,自交系的反应更为敏感,在38%遮荫胁迫下,沈农98A与沈农98B的幼穗长、结穗率、穗行数、行粒数和败育率产生明显差异;郑单958与D90在60%遮荫胁迫下幼穗长和结穗率差异开始明显,其他性状在75%遮荫胁迫下才有明显区别。 相似文献
14.
Varinderpal-Singh Yadvinder-SinghBijay-Singh H.S. ThindAjay Kumar Monika Vashistha 《Field Crops Research》2011
Large field to field variability restricts efficient fertilizer N management when broad based blanket recommendations are used in maize (Zea mays L.). To achieve higher yields and to avoid nitrogen (N) deficiency risks, many farmers apply fertilizer N in excess of crop requirement in maize. Field experiments were conducted for five years (2005–2009) to establish and evaluate threshold leaf colour to guide in-season need based fertilizer N topdressings in four maize genotypes. Colour (of the first top maize leaf with fully exposed collar) as measured by comparison with different shades of green colour on a leaf colour chart (LCC) and maize grain yield was significantly correlated. The Cate–Nelson plot of chlorophyll (SPAD) meter/leaf colour chart values against relative grain yield of 0.93 for the experiments conducted during first two years indicated that LCC shade 5 during vegetative growth stages and LCC shade 5.5 at silking stage (R1) can guide crop demand driven N applications in maize. Evaluation of the established threshold leaf greenness during the next three years revealed that fertilizer N management using LCC 5 starting from six-leaf (V6) stage to before R1 stage resulted in improved agronomic and N recovery efficiency in different maize genotypes. There was no response to fertilizer N application at R1 stage. The study revealed that in maize, fertilizer N can be more efficiently managed by applying fertilizer N dose based on leaf colour as measured by LCC than blanket recommendation. 相似文献
15.
以 35个玉米品种为材料，花期利用遮光度为 50%遮阳网人工模拟寡照环境，测量雌雄间隔期、株高、穗位高、雄穗分枝数、雄穗长度、产量等 14个性状，运用相关性分析、主成分分析、聚类分析、回归分析等多元统计分析方法对玉米品种进行耐荫性评价，筛选出玉米品种耐荫性评价关键指标，根据鉴定指标对玉米品种进行耐荫性划分。利用主成分分析和逐步回归优化出产量、行粒数、雌雄间隔期、穗粗 4个耐荫性评价指标，以产量、行粒数、雌雄间隔期、穗粗 4个性状平均隶属函数值进行聚类分析，将 35个玉米品种分成耐荫性强、耐荫性弱两大类型。通过分析建立玉米品种花期耐荫性评价体系，产量、行粒数、雌雄间隔期、穗粗作为玉米品种花期耐荫性鉴定指标。 相似文献
16.
Shade effects on coffee rust are controversial, possibly because shade helps to prevent high fruit loads, which decreases leaf receptivity to the pathogen but, at the same time, might provide a better microclimate for germination and colonization. These two probable antagonistic pathways are combined under natural conditions. In order to clarify their individual effects, we dissociated the two factors by manually homogenising fruit loads under two light exposure situations, under shade and in full sunlight. The trial was set up in Turrialba, Costa Rica at 600 m of elevation, in a coffee plot initially under shade provided by the tree legume Erythrina poeppigiana. The plot was subdivided into two subplots: one was maintained under shade, whereas shade was eliminated in the second subplot. In each subplot, we removed fruiting nodes from 40 coffee plants in order to obtain the following four levels: none, 150, 250, and 500 fruiting nodes per coffee plant. Coffee rust incidence and severity, along with plant growth and defoliation, were assessed on these coffee plants over a period of two years. Air and leaf temperatures, leaf wetness and relative humidity were also monitored. As expected, the intensity of the coffee rust epidemic increased in line with fruit load. We quantified a 28.9% increase in coffee rust incidence and a 129.2% increase in severity on plants with 500 fruiting nodes as compared to plants with no fruits. With the homogenised fruit load, the intensity of the coffee rust epidemic was greater in the shaded subplot, with a 21.5% increase in incidence and a 22.4% increase in severity. Two mechanisms were suggested. Firstly, we highlighted a dilution effect due to host growth which was 25.2% and 37.5% greater in full sunlight when considering new leaves or new leaf area respectively. Secondly, the microclimate was more conducive to coffee rust under shade, with lower intra-day temperature variations, due to lower maxima, and a higher leaf wetness frequency. We concluded that shade has antagonistic effects on coffee rust. Coffee rust is reduced by shade because shade reduces the fruit load. However, with an equivalent number of fruiting nodes, coffee rust incidence and, to a lesser extent, severity were greater under shade. The service provided by shade in controlling coffee rust is necessarily associated with a disservice that consists in reducing yield in the short term. 相似文献
17.
玉米作为世界种植最为广泛的作物之一，其起源问题一直争议不断。主要有两个假说，一个是保罗·芒格尔斯多夫提出的“三成分起源说”，另一个是乔治·比德尔提出的“大刍草单一起源假说”。分子生物学技术的发展，为单一起源假说提供了直接证据，从而得到了科学界的共识。随着科学技术不断进步，许多研究发现，玉米的大刍草单一起源假说存在诸多解释不通的现象。综合利用考古学、分子生物学、群体遗传学等研究手段，中美学者联合提出了玉米起源的新模型，即“二次起源假说”。约9 000年前，玉米单一起源于小颖大刍草亚种；6 000年前后，玉米又与墨西哥高原亚种发生了一次杂交，发生了第二次驯化，现代玉米都是来自两个不同大刍草的后代。二次起源极大地提高了现代玉米的适应性，墨西哥高原亚种为现代玉米提供了高原适应性和广泛的抗性基因，这为今天玉米成为全球适应性最广和种植面积最大的作物奠定重要的物质基础。该模型为理解人为机制对作物驯化起源的影响提供了良好范例，并为利用野生资源进行作物遗传改良奠定重要理论基础。 相似文献
18.
玉米株型和幅宽对套作大豆碳氮代谢及产量的影响 总被引：3，自引：0，他引：3
在玉/豆套作模式下,采用玉米株型与种植幅宽二因素裂区设计,研究了不同田间配置对套作大豆碳氮代谢与产量的影响。结果表明,较大幅宽和紧凑型玉米下,大豆被荫蔽的程度有所减缓,碳氮代谢变化趋势朝着利于产量形成的方向发展。主要表现为,茎叶中的碳氮含量和关健酶在各时期保持在较高的水平;R4期后叶片中的淀粉迅速降解为糖运至籽粒,而氮的下降速率缓慢。结合前期的研究,我们得出,R2是大豆经历光照转换的重要时期,该时期植株的碳氮代谢能力对大豆后期产量的形成起着重要的作用。而R6期大豆表现出来的碳、氮代谢水平,又能一定程度的反映产量水平。本试验条件下,对玉米、大豆两季作物的经济效益进行分析后得出,利于大豆生长,且保证全年高产,高效的最优组合为：与紧凑型玉米套作,大豆幅宽1.17m,玉米幅宽0.83m。 相似文献