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山西省地处东经110°17′—114°30′,东西经度差4°13′,北纬35°25′—40°25′,南北纬度差为5°20′,全省境内直线距离将近600公里,南北距离远,太阳辐射有很大差别。又因在黄土高原二级阶梯内,境内丘岗起伐,峁梁逶迤,地势的垂直高差悬殊,形成“一地不同天”的立体农业。大麦广布全省:无论山峦盆地均有种植,尤以盆地为多。由于进行了山西省大麦品种的征集、整理和鉴定,初步认定山西省大麦品种的形态生态特点为;(一)类型与变种:在山西省大麦品种中,以棱形分:二棱大麦亚种占6.96%,多棱大麦亚种占93.04%(内四棱大麦占86.95%,六棱大麦占6.08%);以皮裸分:皮大麦占77.39%,裸大麦占22.61%以株型分:半松型占66.95%,紧凑型和松散型各占16.52%。(表1) 相似文献
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本庄公社地处我县西北部,北纬27°31′—27°38′,东径107°52′—107°59′。水稻是该社的主要粮食作物,其产量占粮食总产的60.4%。水稻一般分布在海拔560—800米之间,以种植一季中稻(晚、中熟品种)为 相似文献
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从江“禾”资源的研究初报 总被引：1，自引：0，他引：1
禾是一种特殊的气候生态型稻类,属粳糯,品质特优。它在黔湘桂三省(区)交界处有十来个县种植,以贵州省从江、黎平、榕江三县种植较多形成所谓禾区。禾虽然产量较低,亩产300千克左右,但抗逆性强,高度适应禾区自然条件。少数民族聚居的从江县每年种禾10万亩左右,约占稻田面积一半,在该县粮食生产中占重要地位。从江县位于东经108°14′—109°11′,北纬25°19′—26°2′,处云贵高原的边缘,气候 相似文献
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望谟地处东径105°50′～106°22′,北纬24°5′～25°31′,海拔270～1700米,东高西低;年降水量为1081.2～1339.7毫米;主要集中在6～10月份。冬春干旱,特别是近几年来的春旱严重,雨水来得迟,除给水稻育秧带来困难外,大部分高螃田无水打田,或移栽推迟,甚至改种粗粮或丢荒,若能把杂稻直播在高塝田中获得高产,将给我县在干旱的影响下夺取稻谷增产开辟新的途径。 相似文献
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(一) 贵州位于东经103°36′—109°33′,北纬24°38′—29′14′之间,是一个低纬度、高海拔的高原山区。总面积17.61万平方公里,约占全国面积1.81％。全省平均海拔1100米左右。地势由西向东呈阶梯状大斜坡逐级下降,海拔由西部高原2200米降到中部丘原的1400～1000 相似文献
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糜黍是古老的粮食作物,我省栽培面积约240万亩,主要分布在长城沿线风沙区、陕北丘陵沟壑区、渭北高原区及关中平原区。我省位于北纬31°42′—39°35′之间,跨纬度7°53′,南北狭长,地理环境复杂,气候条件 相似文献
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一、前言湖南省处北纬24°39′～30°08′,东经108°47′～114°15′。属中亚热带季风湿润气候。南北和东西相差五个纬度和五个经度,加之地形起伏,最大高程差达1900多米,形成复杂多样的自然气候条件。全省土地总面积31,777.35万亩(1981年统计数,下同),耕地5,131,97万亩,稻田3,994.11万亩,为耕地的77.8％,种植业以稻作为主。 相似文献
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评价全球气候变化对我国玉米生产的可能影响 总被引：54，自引：6，他引：54
利用我国玉米带１２个有代表性地点的作物、土壤和天气资料，验证了ＣＥＲＥＳ－Ｍａｉｚｅ在我国的适用性，确定了各地有代表性品种在模型中的遗传参数，还对模型进行了敏感性分析，之后，将ＣＥＲＥＳ－Ｍａｉｚｅ在各地当前气候以及在３中由平衡ＧＣＭｓ生成的气候变化情景下分别运行，通过分析与比较模拟结果，评价了当ＣＯ２倍增时，气候变化国各地玉米产量和灌溉需要量的可能影响，对Ｃ煌直接影响也做了考虑。还应用若干农业气 相似文献
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Ho-Young Ban Dana Sim Kyu-Jong Lee Junhwan Kim Kwang Soo Kim Byun-Woo Lee 《Journal of Crop Science and Biotechnology》2015,18(4):265-272
It would be preferable to use a reliable crop growth model for studies on climate change impact assessment. The objectives of this study was to evaluate simulation performance for two maize models, including CERES-Maize and IXIM models, included in the DSSAT model (version 4.6) in terms of phenology and yield. Two early maturing cultivars, Chalok#1 and Junda# 6, were grown under controlled environment in plastic houses at Suwon, Korea. Each cultivar, which was sown at four different date in 2013 and 2014, was subjected to four sets of temperature conditions including ambient (AT), AT+1.5°C, AT+3°C, and AT+5°C. In simulations of phenology under given conditions, the anthesis date and grain filling ratio were underestimated, especially when temperature was unusually high, e.g., in 2013. The maize models also had poor accuracy in grain yield, which resulted from the fact that these models had relatively large errors in simulation of kernel number and kernel weight under elevated temperature conditions. In addition, both models were not able to simulate the drastic decrease of kernel number due to heat stress around flowering periods. These results indicated that two maize models would need improvements in simulation of crop response to supra-optimal temperature before they would be used to assess the impact of the climate change on maize yield. This studies merits further study to improve algorithms in phenology simulation at supraoptimal temperature. 相似文献
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黄淮海夏玉米品种脱水类型与机械粒收时间的确立 总被引：5，自引：0，他引：5
黄淮海一年两熟模式下玉米成熟和熟后籽粒脱水的热量资源紧缺, 是制约机械粒收在该区域发展的关键因素。本文尝试建立黄淮海一年两熟制地区玉米机械粒收适宜品种筛选和以授粉至生理成熟积温和生理成熟期籽粒含水率为指标, 运用双向平均法将参试品种划分为晚熟高含水率(I)、早熟高含水率(II)、早熟低含水率(III)和晚熟低含水率(IV)4种类型。基于玉米生长进程及籽粒含水率动态测试, 估算不同品种播种至适宜机械粒收含水率(28%、25%)所需活动积温, 以黄淮海区夏玉米常年播种日期为起点, 结合历史气象资料的累积计算, 利用地统计分析技术明确不同类型品种适宜机械粒收的时空分布规律, 建立适宜机械粒收时期的预测方法, 为机械粒收在黄淮海区域推广提供指导。选择27个主推品种, 播种至籽粒含水率下降到28%、25%所需要积温分别为, 类型I 2982°C d、3118°C d, 类型II 2770°C d、2873°C d, 类型III 2729°C d、2845°C d, 类型IV 2860°C d、2980°C d。类型III品种降至28%、25%含水率时间分别较类型II品种早2~3 d、约2 d, 较类型IV品种早7~9 d、7~10 d, 较类型I品种早13~17 d、16~17 d。各类型品种籽粒由28%含水率降至25%水平, 所需时间约6~8 d。在当前玉米种植模式及下茬小麦适期播种条件下, 黄淮海南部的豫南、皖北地区, 各类玉米品种均能满足籽粒脱水至适宜机械粒收含水率的要求, 而在黄淮海北部、关中西部以及山东半岛地区, 现有品种很难降至适宜含水率, 需通过选择早熟和籽粒脱水快的适宜品种加以实现。本研究建立的以积温预测籽粒含水率动态变化及其适宜机械粒收时间的预测方法, 为各地合理配置玉米粒收品种、确定适宜机械粒收时间提供了可行的技术方法。 相似文献
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千瓣莲品种资源的RAPD分析 总被引：1，自引：0，他引：1
1School of Life Science, Northwest A & F University, Yangling 712100; 2Wuhan Institute of Vegetable Science, Wuhan 430065 相似文献
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Global warming has lengthened the theoretical growing season of spring maize in Northeast China (NEC), and the temperatures during the growing season have increased. In practise, crop producers adjust sowing dates and alternate crop cultivars to take advantage of the lengthening growing season and increasing temperatures. In this study, we used crop data and daily weather data for 1981–2007 at five locations in NEC to quantify the utilization of the lengthening growing season and increasing temperatures by adjusting sowing dates and cultivar selection for spring maize production. If these two positive factors are not fully utilized, then it is important to know the potential impacts of these climatic trends on spring maize grain yields. The results show that in NEC, both the actual and theoretical growing seasons are lengthening, i.e., the sowing dates have been advanced and the maturity dates have been delayed. The actual sowing dates are 1–8 days later and the actual maturity dates are 6–22 days earlier than the theoretical perspective. Advancing sowing dates and changing cultivars led to 0–5 days and 6–26 days extension of the growing season. For the potential thermal time (TT), adjusting the sowing dates decreased the unutilized TT before sowing, while the cultivar selection increased the utilized TT and decreased the unutilized TT after maturity. On average, the unutilized heating resource before sowing is less than that after the maturity date (0.3–1.9% vs. 2.1–7.8%). During 1981–2007, for per day extension of the growing season, the spring maize grain yield increased by 75.2 kg ha−1. The spring maize grain yields have increased by 7.1–57.2% when both early sowing and changing cultivars during 1981–2007. In particular, adjusting the sowing dates increased the grain yield by 1.1–7.3%, which was far less than the increase effect (6.5–43.7%) from switching to late maturing cultivars. Therefore, selecting late maturing cultivars is an important technique to improve maize grain yields in NEC under the global warming context. Nevertheless, if the currently unutilized TT were fully explored, the local spring maize grain yield would have increased by 12.0–38.4%. 相似文献
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优质蛋白早熟玉米单交种陕单17的选育研究 总被引：6，自引：2，他引：4
优质蛋白早熟玉米单交种陕单17是西北农林科技大学农学院专用玉米研究室,1996年用高赖氨酸自交系Y77QPM为母本,用高赖氨酸自选自交系Y76QPM为父本杂交育成。经过2000—2001年国家玉米区试黄淮海A组试验,2002年国家玉米区试黄淮海夏玉米组生产示范试验,表现出赖氨酸含量0.46%,蛋白质含量11.53%,较普通玉米对照农大108早熟6天,综合抗性好,产量与普通玉米对照接近,可籽粒饲用和粮饲兼用等特点。推荐国家审定,适宜在陕西乃至黄淮海区夏播或春播地区推广种植。陕单17QPM早熟、抗倒、抗病,采用普通玉米骨干杂优模式“黄改系×兰卡斯特群”,采取回交、自交交替转育,其亲本导入亚热带种质,组材新,方法优,它的籽粒品质是本届区试中唯一达到国家普通玉米一等,食用玉米一等,饲用玉米一等,优质蛋白玉米二等的品种,黄淮海夏播区新一代优质蛋白玉米接班品种,该品种已申报国家植物新品种保护。 相似文献
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Susan G. Njeri Dan Makumbi Marilyn L. Warburton Alpha Diallo MacDonald B. Jumbo George Chemining’wa 《Euphytica》2017,213(11):261
Maize (Zea mays L.) is an important source of carbohydrates and protein in the diet in sub-Saharan Africa. The objectives of this study were to (i) estimate general (GCA) and specific combining abilities (SCA) of 13 new quality protein maize (QPM) lines in a diallel under stress and non-stress conditions, (ii) compare observed and predicted performance of QPM hybrids, (iii) characterize genetic diversity among the 13 QPM lines using single nucleotide polymorphism (SNP) markers and assess the relationship between genetic distance and hybrid performance, and (iv) assess diversity and population structure in 116 new QPM inbred lines as compared to eight older tropical QPM lines and 15 non-QPM lines. The GCA and SCA effects were significant for most traits under optimal conditions, indicating that both additive and non-additive genetic effects were important for inheritance of the traits. Additive genetic effects appeared to govern inheritance of most traits under optimal conditions and across environments. Non-additive genetic effects were more important for inheritance of grain yield but additive effects controlled most agronomic traits under drought stress conditions. Inbred lines CKL08056, CKL07292, and CKL07001 had desirable GCA effects for grain yield across drought stress and non-stress conditions. Prediction efficiency for grain yield was highest under optimal conditions. The classification of 139 inbred lines with 95 SNPs generated six clusters, four of which contained 10 or fewer lines, and 16 lines of mixed co-ancestry. There was good agreement between Neighbor Joining dendrogram and Structure classification. The QPM lines used in the diallel were nearly uniformly spread throughout the dendrogram. There was no relationship between genetic distance and grain yield in either the optimal or stressed environments in this study. The genetic diversity in mid-altitude maize germplasm is ample, and the addition of the QPM germplasm did not increase it measurably. 相似文献
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优质蛋白玉米籽粒性状的遗传效应 总被引：2，自引：0，他引：2
选用8个胚乳性状差异显著的优质蛋白玉米(QPM)自交系, 采用Griffing I交配设计组配, 通过对亲本、F1和F2的鉴定, 探讨主要籽粒性状的遗传效应和杂种优势, 为有效利用热带硬质QPM种质改良、扩增我国温带QPM种质以及QPM籽粒性状改良和硬质QPM品种选育提供依据。结果表明, 籽粒百粒重、百粒体积、胚乳修饰度和籽粒密度在F1和F2代都表现一定的正向杂种优势; 胚乳修饰度在F1代存在正反交差异, 母体效应明显; 4个性状的F2代表型值与中亲值的相关性最大; 百粒重和百粒体积主要受母体效应控制, 基因效应以显性效应为主; 胚乳修饰度主要受种子直接效应控制, 基因效应以加性效应为主; 籽粒密度主要受母体效应控制, 基因效应以加性效应和显性效应同等重要。这4个籽粒性状的细胞质效应均较小, 主要受核基因控制。 相似文献
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Maize is the major staple food in southern Africa with human consumption averaging 91 kg capita?1 year?1, and normal maize is nutritionally deficient in two essential amino acids: tryptophan and lysine. Despite the development of quality protein maize (QPM) with high tryptophan and lysine, stunting and kwashiorkor remain high in sub-Saharan Africa due to lack of high yielding and adapted QPM varieties. This study aimed at evaluating a new generation of QPM varieties for yield and related agronomic traits. Before the QPM varieties were validated on-farm, they were simultaneously selected on-station under five different management conditions. In the 2014/2015 season, 10 elite QPM varieties were selected from on-station trials based on high grain yield and stability, and were compared with the best commercial check varieties on-farm. During the 2015/2016 season, some poorly performing QPM varieties were dropped while new ones were added, resulting in 12 elite QPM varieties being evaluated on-farm. Analysis of variance for the 2014/2015 season showed non-significant hybrid × management condition interaction. Mean grain yields across management conditions ranged from 1.5 to 4 t ha?1 and were higher under mild stress (2.3–5.5 t ha?1) compared to random stress conditions (1.1–2.9 t ha?1). Broad sense heritability estimates were low to moderate (11–69%), and thus could still permit effective selection of better genotypes. Yield advantage ranged from 12 to 25% across the 2 years, suggesting effective genetic gains in QPM breeding. QPM hybrids CZH132044Q, CZH142238Q and CZH142236Q were stable and high yielding. Promotion of such QPM hybrids may help reduce protein energy malnutrition. 相似文献