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Development Traits Affecting Time to Low Ear Moisture in Maize 总被引：2，自引：0，他引：2
A diallel cross of six inbred lines of maize (Zea mays L.) from the Corn Belt of the USA and one inbred line (NZ1A) with characteristics of maize from the highlands of Mexico was grown in a cool, temperate environment. The objective was to investigate interrelationships and combining abilities of plant development traits likely to influence the time required to reach low ear moistures in the field. The traits were days to silking, days to physiological maturity, ear moisture at physiological maturity, grain filling duration and ear drying rate after physiological maturity. Grain yield and grain moisture at harvest were also considered. Differences among the hybrids of this diallel cross for ear and grain moisture at the usual harvest time were largely determined by differences in ear drying rate after physiological maturity, and not by differences in days to silking, days to physiological maturity, or in ear moisture at physiological maturity. General combining ability (GCA) effects were much larger than specific combining ability (SCA) effects for all traits. NZ1A had positive GCA effects for grain filling duration and negative GCA effects for ear moisture at physiological maturity which were outside the range of the Corn Belt lines suggesting that this line, or similar Mexican germplasm, could be useful for developing hybrids with high grain yields and low ear moistures at harvest in cool, temperate environments. 相似文献
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旨在明确玉米果穗乳熟期穗轴、籽粒、苞叶、穗柄水分运动变化。本文利用生育期一致，乳熟期籽粒脱水速率差异的品种‘先玉696’、‘合玉29’为供试材料，采用烘干减重法（《ISTA水分测定手册》2007）测定乳熟期穗轴、苞叶和籽粒含水量与不同时期变化量与吸湿法测定穗柄中水分运动，结果显示不同脱水类型品种玉米穗轴、苞叶和籽粒展现出相同的趋势苞叶＞籽粒＞穗轴，先玉696快于合玉29。脱水快品种先玉696表现出随着生育期推移茎秆向果穗输水逐渐下降，苞叶含水量前期快速降低，籽粒含水量下降较快。脱水慢品种合玉29茎秆向果穗输水量高于先玉696并且输水量没有发生变化，苞叶水分降低缓慢，籽粒含水量下降缓慢。本研究也显示籽粒脱水与苞叶、穗轴的脱水速率密切相关。籽粒生理成熟后自然脱水过程中水分并没有由果穗向茎秆转移，茎秆对果穗脱水起负效应，但不同品种输水量和变化量不同（差异不显著）。 相似文献
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为研究施氮量对春玉米籽粒脱水特性与灌浆特性的影响,确定冀东地区春玉米品种的适宜施氮量,以低氮型玉米品种京农科728和高氮型玉米品种先玉335为供试材料,大田条件下设置N 1(120 kg·hm-2)、N 2(180 kg·hm-2)、N 3(240 kg·hm-2)、N 4(300 kg·hm^(-2))、NCK(360 kg·hm-2)5个施氮量处理,构建了两品种在不同施氮量下籽粒、苞叶和茎秆含水率与授粉后活动积温的关系模型。结果表明,京农科728籽粒含水率下降所需要的积温均低于先玉335,京农科728在N 1水平下收获时籽粒、苞叶和茎秆含水率最低,脱水速率最快,籽粒灌浆速率高;先玉335在N 4水平下收获时籽粒含水率最低,生理成熟后脱水速率最快,N 3水平下苞叶和茎秆含水率最低,籽粒灌浆速率最高。生理成熟前注重灌浆速率的提高,收获期籽粒含水率与生理成熟后籽粒平均脱水速率呈负相关,与籽粒总脱水速率呈极显著负相关,说明收获期籽粒含水率主要由生理成熟后籽粒平均脱水速率和籽粒总脱水速率决定。低氮型玉米品种京农科728适宜施氮量为120 kg·hm-2,此时脱水与灌浆特性表现较好;高氮型玉米品种先玉335适宜施氮量为300 kg·hm-2,此时脱水与灌浆特性表现较好。 相似文献
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不同玉米自交系子粒脱水速率及其与主要影响性状的相关分析 总被引：2，自引：0，他引：2
为了明确不同群体玉米自交系子粒脱水特征差异和影响玉米脱水速率的主要性状与子粒脱水间的关系,以陕A群、陕B群选育的8份玉米自交系和2份骨干自交系（昌7-2和PH4CV）为试验材料,分析了不同玉米自交系的子粒脱水速率、收获期子粒含水率、子粒灌浆速率、苞叶性状、果穗性状、叶面积、叶绿素含量、株高、穗位高及产量构成等变化特征及其与子粒脱水间的相互关系。结果表明：不同玉米自交系子粒脱水速率呈现“快–慢–较快–慢–较快–慢”的变化趋势。子粒脱水速率与收获期子粒含水率、苞叶平均含水率、苞叶层数、苞叶长度、穗粗、粒长、粒宽、叶面积、SPAD值、子粒灌浆天数等性状呈显著负相关关系,与苞叶脱水速率存在显著正相关关系,与株高、穗位高和子粒产量间相关性不显著。不同自交系间的子粒脱水速率、收获期子粒含水率、苞叶含水率、苞叶脱水速率等指标差异明显,KB043、KA105和KB024自交系的子粒脱水速率快、产量较高,可在宜机收品种选育时作为快速脱水材料加以考虑。 相似文献
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以山西省中晚熟区大面积推广、生育期基本相同的20个玉米品种为试验材料,对穗部相关性状与收获期子粒含水率进行相关性分析和通径分析。相关性分析结果表明,收获期子粒含水率与穗粗、轴粗、粒厚、苞叶总面积、收获时苞叶含水率呈极显著正相关,与粒宽呈显著正相关,与行粒数呈极显著负相关。通径分析结果表明,对收获期子粒含水率直接作用大小排列为穗行数>穗粗>苞叶含水率=粒厚>轴粗>行粒数>粒宽>穗长>苞叶总面积。因此,要选育收获期子粒含水率低的玉米新品种,应着重选育苞叶总面积小、收获时苞叶含水率低、穗粗与轴粗、子粒厚度薄、子粒宽度窄、行粒数多的基因型。 相似文献
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玉米生理成熟后倒伏变化及其影响因素 总被引：15，自引：0，他引：15
针对机械粒收玉米生理成熟后田间站秆脱水期间的倒伏问题, 本研究通过多点试验调查夏玉米和春玉米生理成熟后倒伏发生类型和规律, 分析影响玉米生理成熟后倒伏发生的关键因素。结果表明, 玉米生理成熟后, 茎折率升高是倒伏增加的主要原因; 茎折率随抗折力降低而升高, 抗折断力降低至14.3 N时, 茎折率超过5%; 植株重心高度逐渐降低, 茎秆基部第3节间穿刺强度(RPS)、第4节间压碎强度(CS)、第5节间弯曲强度(BS)均逐渐降低, 基部节间单位长度干重(DWUL)和含水率也逐渐降低; 茎秆抗折断力与RPS、CS、BS、DWUL和含水率均呈极显著正相关, RPS、CS和BS均与DWUL和含水率呈极显著正相关。本研究表明, 玉米生理成熟后植株自然衰老导致的茎秆干物质降低和水分含量下降, 是茎秆机械强度降低、茎折率增加的主要原因。因此应适期收获, 避免田间站秆时间过长引起倒伏率增加导致的收获产量损失。 相似文献
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荔枝和龙眼种子发育过程发芽率与脱水忍耐力变化 总被引：3，自引：0，他引：3
荔枝和龙眼种子发育成熟时不经历脱水干燥过程，成熟采收时种子含水量（fwb）分别达44．6％，42．5％。荔枝和龙眼新鲜种子不经脱水干燥处理即可萌发，并且在所有发育时期均不能忍耐较大程度的脱水。但对部分脱水的忍耐力在发育中有所升高，种子生理成熟时最大，然后略有下降。初步探讨了荔枝和龙眼种子发育过程脱水忍耐力与顽拗性种子采后生理行为的关系． 相似文献
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极早熟玉米品种籽粒脱水特性的初步研究 总被引：13，自引：2，他引：11
采用裂区设计方式,对5个极早熟玉米品种的籽粒含水率及脱水速率进行了研究,结果表明品种间生理成熟时的籽粒含水率存在显著差异,变化幅度为35.61%～42.17%;收获时的籽粒含水率品种间差异极显著,变化幅度为15.49%～28.50%。抽丝后35d至生理成熟前籽粒平均脱水速率品种间差异显著,变化范围为0.5296%/d～0.9007%/d;生理成熟后至收获期籽粒的平均脱水速率品种间差异显著,变化范围为0.4246%/d～0.5935%/d。出苗至抽丝的天数、株高、灌浆期绿叶数、单穗产量等性状与籽粒含水量存在显著的相关关系,穗长和穗粗等性状对脱水速率有显著影响。另外试验条件下相对湿度对生理成熟后部分品种的脱水速率影响显著。 相似文献
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北疆玉米大田机械粒收质量调查 总被引：1，自引：0，他引：1
北疆是我国玉米机械粒收率最高的区域,为了解北疆玉米大田粒收质量现状,2012-2017年在新疆奇台总场、伊犁新源71团、伊宁县和温泉县等地农户田块调查了机械粒收质量,共获得269组样本,结果表明：（1）子粒破碎率均值为6.38%,高于5%的国家标准[玉米收获机械技术条件（GB/T 21961-2008）]要求;杂质率和产量损失率均值分别为0.41%和0.96%,分别低于3%和5%的国家标准要求,子粒破碎率高是当前北疆玉米大田机械粒收存在的主要质量问题。（2）收获玉米子粒含水率均值为23.3%,其与破碎率呈显著相关,可用二次函数y=0.0263x 2-1.0433x+15.867（R 2=0.108,n=269）拟合。（3）在子粒含水率相同条件下,不同品种之间子粒破碎率表现出明显差异,其中,新引M751子粒破碎率明显低于KWS2564,而KX3564介于两者之间。（4）筛选早熟、脱水快、耐破碎品种,实施玉米密植高产全程机械化绿色生产,可以有效改善机械粒收质量,实现玉米高产高效协同。 相似文献
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为筛选适合陇东旱塬区耐密高产且宜机械粒收的玉米品种,于2019-2021年在甘肃平凉泾川高平试验基地对引进不同生态区的玉米品种采用福田雷沃谷神收割机进行籽粒直收。结果表明,参试品种平均产量接近于吨粮田,2019、2020和2021年产量分别为14 424.0、14 295.0和14 737.5kg/hm2,品种间产量存在显著差异,产量极差分别为3826.5、4992.0和3699.0kg/hm2。参试品种含水率变幅较大,最大相差7.2%、10.6%和5.2%。不同玉米品种延迟收获,籽粒含水率呈线性下降,以生理成熟后22.7d为适宜粒收期,且收获期含水率为25.0%、20.0%和13.9%时,籽粒破碎率依次为2.82%、1.68%和1.20%。品种MC703和先玉335破碎率3年平均分别为3.84%和2.99%,杂质率分别为0.49%和0.35%,迪卡519破碎率和杂质率2年平均为4.66%和0.12%,均符合国家粒收标准。因此,陇东旱塬适宜粒收的含水率为<25.0%。机械粒收相比机械收穗和人工收获分别节省成本1800和3600元/hm2。综合评价,推荐收获期含水率（<25.0%）低、耐破碎性能好和单产水平高的迪卡519、MC703和先玉335作为陇东旱塬区适宜机械粒收品种。 相似文献
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鲜食糯玉米鲜果穗生长规律研究 总被引：3，自引：1，他引：2
摘 要：本文通过对两个鲜食糯玉米品种津农3和津农0802授粉后不同时期时,籽粒中可溶性糖含量以及水分含量的变化研究发现,在授粉后21-27天收获的鲜食糯玉米,可溶性糖含量与水分含量较高且较稳定。 相似文献
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Grain moisture in maize at harvest depends on the grain drying rate (GDR) after physiological maturity. The maize plants with high GDR can reduce grain moisture rapidly, which will shorten the drying time after harvest and prevent the grain to be mildew and enhance maize quality. In this study, A total of 280 recombinant inbred lines that were derived from a cross between Ji846 (high drying rate, 1.18 % day−1) and Ye3189 (slow drying rate, 0.39 % day−1) were used to construct genetic linkage map and identify QTL underlying GDR in different environments. A genetic linkage map was constructed containing 97 SSR and 49 AFLP markers, which covered 2356.8 cM of the maize genome, with an average distance of 16.1 cM. Composite interval mapping identified 14 QTL for GDR after physiological maturity located on chromosomes 2, 3, 5, 6 and 8. The additive effects of QTL were all from Ji846. The range of phenotypic variation explained by the QTL was 5.05–16.28 %. But only two QTL (qKdr-2-1, qKdr-3-6) were identified across both locations. qKdr-2-1 positioned between the markers phi090-umc1560 on chromosome 2 explained 15.59 % of the phenotypic variance, and the other qKdr-3-6 positioned between the markers phi046-bnlg1754 on chromosome 3 explained 10.28 % of the phenotypic variance. 相似文献
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渐密种植条件下玉米植株形态特征及其相关性分析 总被引：10，自引：0，他引：10
在大田条件下,以郑单958、先玉335、登海661和益农103为试验材料,采用行距固定(80 cm×40 cm大小行)、株距从1 m开始由大至小的“渐密”种植方式,形成1.67~16.67株 m-2共13个种植密度,在拔节期、大喇叭口期和生理成熟期分别测定株高、茎粗、穗位高、产量等指标,研究密度对玉米植株形态特征的影响及其相互作用效应。结果表明,随着密度的增加,株高呈先增加后降低的抛物线变化,穗位高和穗株比不断增高,当穗株比大于0.4时植株易倒伏,降低穗位高可明显减少植株倒伏率;穗下各节间呈伸长趋势,而穗上各节间呈缩短趋势,整株自下而上各节间粗均呈减小趋势,而各节间宽窄比无显著变化。植株株高、穗位高、茎粗等形态指标间对密度协调反应,共同对密度变化作出响应。茎部的伸长主要表现在穗位以下各节间,穗位高、穗株比与各时期的茎粗均成极显著负相关(r = –0.7701**以上)。 相似文献
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Effect of Time of Harvest and Storage Conditions on Germination of Nutmeg (Myristica fragrans Houtt)
U. R. Sangakkara 《Journal of Agronomy and Crop Science》1993,170(2):97-102
Nutmeg ( Myristica fragrans ) is a valuable tropical spice crop, which is not easily propagated vegetatively. As the seeds of this species lose viability soon after harvest, storage for research causes problems, especially due to the seasonality of production. Thus, a study evaluated the characteristics of nutmeg seeds, and the relationship between time of harvest, drying temperature, and storage condition on germinability. Seeds were picked at full maturity, full ripeness or were collected within 2 hours after falling from the tree. Seed moisture contents, germination characters and germination indices were determined soon after harvest. The freshly fallen seeds were used for the drying and storage due to their better germination characters and higher germination index.
Seed moisture contents were high in the seeds. These values decreased and germinability increased with increasing seed maturity. Germination percentages were lost at higher moisture contents at a faster rate when dried at higher temperatures. All seeds lost germinability at moisture contents below 45 % (dry wt basis) when dried at the selected temperatures. Germination of stored seed were maintained for a longer period of time when stored at 5 °C in sealed transparent polythene packs, in contrast to when stored at room temperature. The results suggest the recalcitrant nature of nutmeg seeds and present possible methods of storage for short period of time while maintaining some degree of germinability. 相似文献
Seed moisture contents were high in the seeds. These values decreased and germinability increased with increasing seed maturity. Germination percentages were lost at higher moisture contents at a faster rate when dried at higher temperatures. All seeds lost germinability at moisture contents below 45 % (dry wt basis) when dried at the selected temperatures. Germination of stored seed were maintained for a longer period of time when stored at 5 °C in sealed transparent polythene packs, in contrast to when stored at room temperature. The results suggest the recalcitrant nature of nutmeg seeds and present possible methods of storage for short period of time while maintaining some degree of germinability. 相似文献
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为了探究玉米籽粒含水量和脱水速率在各个生长时期变化趋势及其相关性,本研究以‘浚单1538’、‘高玉1668’、‘浚单18’共3个不同玉米单交种为材料,利用相关分析和回归分析模型对主要农艺性状进行了分析。结果表明不同类型品种籽粒含水量和脱水速率差异较明显,变化趋势不尽相同。籽粒含水量、整穗含水量和穗部叶片含水量呈显著正相关,与穗上节和苞叶含水量有较强的正相关,与地上第三节和穗上节穿刺力有较强的负相关性,但均未达到显著水平。籽粒脱水速率与整穗脱水速率呈显著正相关,与地上第三节和穗部叶片脱水速率负相关性较强,但未达到显著水平。利用探针式水分测定仪测量玉米整穗含水量与烘干法水分数据呈显著正相关,建立了计算玉米籽粒真实水分读数的数学模型：y=1.565x-91.455 (R 2=0.63),优化了利用探针式水分测定仪进行籽粒含水量测定的方法,利用籽粒水分校正值分析籽粒脱水速率相关性状与烘干法结果基本一致。利用探针式水分测定仪测定茎秆含水量和叶片含水量与烘干法相关性较小。 相似文献
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Moisture content influences harvest timing and the consequent drying process and drying costs, and the development of spoilage fungi during pre- and post-harvest phases. Maize kernel development in the field can be partitioned into three phases: i) lag phase, ii) grain filling and maturation drying, and iii) post-maturity dry-down. A model simulating maize kernel moisture content during maturation can help either monitoring or foreseen maize kernel humidity during the harvest period. Also, it would be useful in simulation studies via crop models to estimate the infield feasibility of harvest but also the interaction with diseases responsible for mycotoxin production, against weather scenarios.A process-based model was developed, called MIMYCS.Moisture. When the hybrids were analyzed all together, MIMYCS.Moisture showed a good general predictive capability with an average error in moisture estimation of ±3.28% moisture (considering the root mean square error – RMSE). The model efficiency (EF) was positive (0.85) and the model was able to explain the 89.7% of variation. When the two sub-models were analyzed separately, the RMSE remained approximately at the same level of the general model, while the other indicators changed revealing the different characteristics of the two models. The developmental moisture sub-model has a slight tendency to overestimate, while the dry-down sub-model tended to underestimate final moisture content.However, when the model was analyzed separately for each hybrid, both calibration and validation results suggested that more data are needed to improve the model likely with respect to kernel characteristics of hybrids. Finally, the equilibrium moisture content equation used, taken from industrial drying models, might not be adequate for simulating the field conditions where temperature is well below the one in dryers and environmental air humidity may vary considerably across sites and harvest periods. 相似文献