国家大豆品种区域试验对照品种的生育期组归属

以38个分属MG000~MGVIII的北美大豆生育期组标准品种的生育期表现为参考, 通过多点对比试验, 对来自16个试验组的国家大豆品种区域试验19个对照品种进行生育期组鉴定与划分。所有品种均在北京、武汉两地春播, 并选用部分代表性品种在18个国家大豆品种区域试验点进行补充试验。结果表明, 国家大豆品种区域试验对照品种的生育期组介于MG0~MGVI之间。不同区域的对照品种可归属相同的生育期组。北方春大豆区晚熟组、西北春大豆区、黄淮海夏大豆区及西南山区春大豆区的对照品种均属MGIII;长江流域春大豆区、热带亚热带夏大豆区对照品种属MGV或MGVI。热带亚热带春大豆区2个对照品种福豆301和泉豆7号所在生育期组差异较大, 分别归属MGII和MGIV。根据生育期组并考虑其他因素, 建议将黄淮海夏大豆品种区域试验组由目前3个组以黄河为界划分为2个组, 并对南方部分试验组进行调整。北方春大豆晚熟组和西北春大豆区对照品种尽管生育期组相当, 但因品种抗旱性要求不同, 建议分别设置区域试验。     

夏播大豆生育期结构对农艺性状的影响

在北京生态条件下，选取生育期在100d以内的我国南方及国外38个大豆品种，进行生育期结构与农艺性状遗传变异方面的研究，试验结果表明：遗传力较高的有大豆主茎分枝始节R1、生育前期、全生育期、荚长、主茎节数、主茎分枝数、单株粒数。筛选出一批对光温反应不敏感、早熟、高产大豆品种。     

生育期结构不同的大豆品种的光周其反应和农艺性状

分别选用成熟期相近、开花期不同及开花期相近、成熟期不同的南方春、夏大豆品种,研究了生育期结构与开花前、后光周期反应敏感性的关系。结果表明,大豆品种生育前、后期长短与它们在该期的光周期反应敏感性正相关。在生育期相近的前提下,前期长度与开花促进率（ＦＨＲ）、后期长度与成熟促进率（ＭＨＲ）正相关;开花期相近的品种,后期长度与ＭＨＲ值正相关。部分品种不符合以上趋势,反映出上述相关的复杂性。在生育期相近的南     

不同播种期对大豆产量及相关农艺性状的影响

为了筛选适合陕西省延安市不同播种时期救灾补种的品种及探索大豆最适播种时期,试验选用10个大豆品种(系),分4期播种,调查相关农艺和产量性状。结果表明,不同播种期对大豆农艺性状及产量的影响明显,随着播种期的延迟各大豆品种(系)的株高、主茎节数、单株结芙数、单株拉数、百拉重均呈递减趋势,且总生育日数也随播种期的延迟而呈现缩短的趋势。其中,第I播种期(5月21日)参试大豆品种(系)的农艺性状和产量性状整体表现均最好,为陕西省延安市的最适播种期;晋豆42和汾豆78的4个播种期生育期、农艺性状及产量均较其他品种(系)表现良好,可作为陕西省延安市不同播种时期救灾补种的最适品种。     

大豆落花落荚率与品种生育阶段的关系

以 2 4个栽培品种为试材 ,研究不同大豆品种生育阶段的遗传差异对大豆花荚脱落的影响。结果表明 :不同品种各生育阶段的生育日数 ,遗传差异达极显著平准 ;不同结荚习性的大豆品种落花落荚时期基本相同 ,但出现的高峰期有差异 ;落花落荚率不仅与品种的开花阶段、结荚阶段日数呈极显著负相关 ,并均有显著的回归线性效应。     

安徽淮北地区主栽大豆品种生育期组划分的研究初报

为了明确安徽淮北地区主栽大豆品种生育期组的划分,方便大豆不同地区之间的引种,于2012、2013年以13份北美大豆标准品种MG(maturity group)Ⅱ-MGⅤ生育期组为参照,通过2年对比试验,对安徽淮北地区22份主栽品种和最近几年新育成品种的生育期组进行划分。结果表明,13个北美标准品种在宿州均能正常成熟,22份试验品种的生育期组介于MGⅡ-MGⅤ。其中,在MGⅡ组和介于MGⅣ-MGⅤ组的品种各有1个,均占参试品种数的4.5%;MGⅢ组和介于MGⅢ-MGⅣ组的品种各有8个,均占参试品种数的36.4%;;MGⅣ组有4个,占参试品种数的18.1%。综合2年的试验结果,安徽淮北地区的主栽品种主要集中在MGⅢ和MGⅣ两个生育期组内。     

中国大豆遗传资源的分析研究——Ⅰ.不同栽培区大豆遗传资源的生育期

本文分析了中国各大豆栽培区大豆遗传资源的生育期表现,东北春大豆区的大豆品种多为早熟和极早熟种。黄淮夏大豆品种以中热种居多。长江流域夏大豆品种成熟期分布比较分散,晚熟和极晚熟种多于早熟和中熟种。秋大豆则以中熟种占多数,大豆是以不同生育期和播期类型适应各地条件的,不同生育期的大豆遗传资源极为丰富。     

不同遮光胁迫对大豆生长发育进程及形态性状的影响

通过遮光处理,研究不同遮光强度及持续时间对大豆的生育进程和形态性状的影响,结果表明,大豆播种后遮光20%~50%,时间持续到V3期以后,大豆各生育阶段所需生育日数减少,生育期缩短。遮光20%时间持续到V3以后,遮光30%时间持续到R1以后,遮光50%时间持续到R5以后,大豆生育期显著或极显著缩短。同一遮光持续时间,遮光强度的加强会导致R5-R8生育日数增加,使大豆生育期(VE-R8)延长。遮光强度及遮光持续时间对大豆株高、子叶节高度、茎粗和主茎节数影响显著。遮光50%持续到R5期以后,植株形态由直立变成蔓生型。     

不同播期对伊大豆1号产量及生育进程的影响

本文研究了不同播种期对伊大豆1号产量及生育进程的影响,结果表明,6月4日前播种对大豆产量影响较小,6月14~25日播种产量有所下降,但均达到了2 250 kg/hm2。另外,播期对大豆生育期影响较大,6月4日前播种的大豆生育期在95 d左右,6月9~25日播种的大豆生育期在91~92 d。     

夏播大豆品种的生育期特性与农艺性状的关系分析

从 339个大豆品种中选取生育期小于 1 0 0d的 1 0 3个品种进行生育期结构特性与农艺性状的分析。结果表明 :①R1最长的为华北品种 ,最短的为外国品种 ;②R7最长的为东北品种 ,最短的为南方品种 ;③R1与生育前期即营养生长阶段 ,高纬地区长于低纬地区 ;R7与生育后期即生殖生长阶段 ,低纬地区长于高纬地区 ;④R1、生育前期长的品种 ,单株荚数、单株粒数多 ,株高较高 ;R7、生育后期长的品种 ,百粒重高 ;⑤筛选出一批对光温不敏感的品种     

不同播种期花椰菜生长发育特性

在露地条件下研究了2个品种的花椰菜在7个播种期下的生长发育特性，同时探讨了环境条件对花球形成的影响。结果表明，在不同播种期下，花椰菜的生长发育状况存在很大差异，但现球期和成熟期之间存在极显著的正相关；在一定播种期内，叶片数可作为花球形成的一个形态指标；在不适宜的花球诱导条件下，影响花球形成的因素极其复杂，高温和减少光照时间均能抑制或推迟花球的形成。     

江苏不同熟期粳稻品种的齐穗期和安全播期预测

为明确当前江苏各地不同熟期粳稻品种的安全播期,以江苏的4个熟期类型的5个常规粳稻品种为材料,在江苏连云港(34°83′N)、淮安(33°34′N)、扬州(32°25′N)和苏州(31°18′N)等4地,进行自5月10日起每10天1期,共8个播期的播种试验,得出各播期的相应齐穗期。以齐穗期温光预测模型y=a＋b₁x₁＋b₂x₂拟合其实得的播期与齐穗期资料。用该模型拟合4个试验点、5个供试品种计20组数据,得出20个预测式,其拟合度R²在0.9927~0.9998之间,均达极显著水平。用各试点所在地近25年各年粳稻品种安全齐穗期及逐日平均温度,依齐穗期光温模型预测式经多次迭代推得各年的安全播期,进而求得90%保证率的安全播期并作各地生产应用分析。在江苏淮北的北部,麦稻两熟田水稻的可播栽始期为6月15日,中熟中粳的安全播期为6月21日,此类品种可用于该地直播;其他各熟期类型品种安全播期均早于当地可播栽始期,故不能用于直播。在淮北南部稻麦两熟田的可播栽始期为6月12日左右,中熟中粳和迟熟中粳的安全播期分别在7月4日和6月22日,此两类品种可用于该地麦茬直播;早熟晚粳安全播期在6月17日、18日,在大面积生产中因接茬时间过紧应慎用于麦茬直播;中熟晚粳的安全播期为6月8日,不可用于直播。在苏中南部,水稻可播栽始期为6月8至11日,中熟中粳、迟熟中粳、早熟晚粳类型两品种的安全播期分别在7月12日、3日、6月25日和28日,可用于该地直播;中熟晚粳的安全播期为6月11日,用于直播接茬时间太紧,不可应用。在苏南,水稻的可播栽始期为6月5日,供试4熟期类型品种的安全播期分别为7月18日、13日、9日至10日和7月3日,仅考虑安全齐穗各熟期类型品种均可用于麦茬直播,但因中粳类型品种直播稻生育期过短、产量不高,不宜应用。     

四川地区彩色花生一年两熟种植时期研究

为解决四川花生新品种繁育加代慢、鲜食花生供应周期短的问题,试验探究了四川地区花生一年两熟的可行性。试验以‘蜀花1号(SH1)’、‘蜀彩花1号(SCH1)’、‘蜀彩花2号(SCH2)’3个彩色花生品种为材料,在四川攀西仁和试验基地对其在全年不同月份播种的生长发育状况、产量相关性状及繁殖系数进行了研究。结果表明：各个品种自身产量最高的种植时期有所不同,但时期差异不大,种植时间对各品种生长性状和产量性状均产生显著性影响,在1—9月播种期间出苗率、成熟株高、单株结果数、繁殖系数呈现先升高后降低的表现趋势,生育期则与之相反,因积温过低等气候条件限制,10—11月播种3个品种均未结果。进一步分析发现：5月播种‘SCH1’的单季繁殖系数为试验最高值,加权平均计算结果显示,3月播种‘SH1’和‘SCH2’时的全年繁殖系数最高,1月播种‘SCH1’的全年繁殖系数最高,最适宜一年两熟种植。结果证明：在攀西地区进行花生一年两熟种植可行,尤其是使用生育期较短的品种效果更好,可延长四川地区鲜食花生供应时长,同时为四川花生新品种本地快繁加代提供可能。     

在不同环境条件下优质蛋白玉米品种的物候期模型

传统农业研究方法的结果通常具有地域性, 且周期长, 且投入大, 用作物生长模型模拟技术, 是解决这一问题的理想方法. 为了用CERES玉米生长模型预测栽培管理措施对不同品种生长发育的影响, 在泰国北部清迈大学农学院的多熟种植中心(北纬18°47′, 东经99°57′, 海拔300m)进行品种×播种期的双因素试验, 参试种为:Across 8763(     

不同生育时期遮阴对大豆形态性状和产量的影响

间套作是提高土地利用率,促进农作物高产的重要技术,而遮阴限制间套作大豆产量,且间作和套作大豆被遮阴的生育时期不同。为明确不同生育时期遮阴对大豆形态性状和产量的影响,2010-2012年用透光率50%的遮阳网对桂夏2号、南豆12、南冬抗22、E61和C103遮阴处理,结果表明,不同生育时期遮阴对各形态指标影响程度不同,前期遮阴(VER1和VER2)对主茎长、主茎长/茎粗等主茎形态性状有(极)显著影响,主茎长、主茎长/茎粗比值平均比对照分别高45.75%,93.64%;后期遮阴(R1R8和R2R8)对分枝数和底荚高度等形态性状有(极)显著影响,分枝数平均比对照低29.97%,底荚高度平均比对照高28.59%;各品种产量受前后期遮阴影响程度不同,R/V比值低于1.4的品种产量受前期遮阴影响更大,R/V比值大于等于1.5的品种产量受后期遮阴影响更大;相关分析和通径分析结果表明,主茎长、第一节间长、分枝高、主茎长/茎粗比值和主茎长/分枝数比值与单株产量呈极显著负相关,分枝数与单株产量呈极显著正相关,主茎长/茎粗比值和主茎长/分枝数比值是间接反映大豆产量高低的重要指标。     

Rice reproductive growth duration increased despite of negative impacts of climate warming across China during 1981–2009

Changes in rice phenology during 1981–2009 were investigated using observed phenological data from hundreds of agro-meteorological stations across China. Spatiotemporal changes of rice phenology across China, as well as the relations to temperature, day length and cultivars shifts were analyzed and presented. We found that major rice phenological dates generally advanced while rice growing period changed diversely for different rice cultivation systems in different agro-ecological zones. Length of vegetative growth period (VGP) increased at 59 (67.0%) stations for single-rice, however, decreased at 36 (54.5%) and 35 (51.5%) stations for early-rice, and late-rice, respectively. Length of reproductive growth period (RGP) increased at 71 (70.3%) and 49 (55.7%) stations for single-rice and early-rice, respectively, however, decreased at 46 (54.8%) stations for late-rice. The changes were ascribed to the combined effects of changes in temperature, photoperiod and cultivar thermal characteristics. Increase in temperature had negative impacts on the lengths of VGP and RGP. Day length slightly counterbalanced the roles of temperature in affecting the duration of VGP. Furthermore, we found that during 1981–2009 cultivars with longer growth duration of VGP were adopted for single-rice, but cultivars with shorter growth duration of VGP were adopted for early-rice and late-rice. Cultivars with longer growth durations of RGP were adopted for single-rice and early-rice, as well as late-rice at the middle and lower reaches of Yangtze River. However, in the southwestern China and southern China, cultivars with shorter or almost same growth duration of RGP were adopted for late rice.     

Seeding date effects on rough rice yield and head rice and selection for stability

The rice (Oryza sativa L.) crop in Arkansas is seeded from late March through early June each year. Farmers need new rice cultivars that not only produce both high rough rice yields and high head rice across this range of seeding dates but do so consistently. Thus, a seeding date study was conducted during 1994 and 1995 at Stuttgart, Arkansas, to study seeding date effects on rough rice yield and head rice and selection for stability. Fourteen rice cultivars were seeded at five dates ranging from late March through mid-June. Kang's yield-stability statistic was used to select cultivars for both high rough rice yields and high head rice as well as stability for both traits. Plant stands from March seedings of each year were significantly lower than for the later seeding dates. Maturity (days to 50 percent heading) was extended at the early seeding dates. Some rice cultivars, such as ‘LaGrue’, had lower and more variable head rice when seeded early. In the June seeding dates each year, ‘Kaybonnet’ produced rough rice yields that were more consistent with yields when planted at the earlier planting dates. ‘Bengal’, ‘Cypress’, ‘Kaybonnet’, and ‘Newbonnet’ were cultivars selected by Kang's stability statistic, which was targeted to select cultivars with stable, high rough rice yields and stable, high head rice. The validity of using Kang's yield-stability statistic for cultivar selection is also evident empirically by the adaptation and wide use of these four cultivars by southern U.S. rice producers. These results indicate that seeding date studies and stability analyses would be useful tools for rice breeders to identify cultivars that will be readily adapted and grown by rice producers. This revised version was published online in July 2006 with corrections to the Cover Date.     

Incidence of and yield loss caused by maize rayado fino virus in maize cultivars in Ecuador

Three sowing date trials, each planted with one cultivar, were performed to measure the natural incidence of the Maize rayado fino virus (MRFV). The lowest incidences (1–6%) were obtained at the sowing dates normally practised in the tested regions. Earlier or later sowing dates had higher to much higher incidences (up to 18 and 32%). Two cultivar trials, one with four cultivars and one with eight cultivars, showed significant differences in incidence, ranging from 14.0% in ‘Iniap-160’ to 2.0% in ‘Cadet-2’. In one trial with plots of 1000 m², the cultivar Iniap-122 was sown at three sowing dates. In each plot, plants that developed MRFV symptoms at the 8–10 leaf stage, at the 12–14 leaf stage and at the emergence of tassels were marked. Marked MRFV-affected plants were compared with non-MRFV-affected plants in their neighbourhood to estimate yield loss due to MRFV. The yield losses at the three sowing dates were 2.5, 1.6 and 4.8%, respectively. It was concluded that the yield loss due to MRFV is quite small provided sowing is restricted to the normal sowing period.     

不同小麦品种产量对冬前积温变化的响应

为确定河北省中部地区小麦品种适播期,筛选耐迟播品种,2011年秋至2014年夏在河北藁城采用播期×品种二因子裂区试验,研究了不同播期对当地12个主栽小麦品种产量的影响以及不同品种对冬前积温的响应。结果表明,播期对小麦产量有显著影响;不同品种对播期响应差异明显,分为迟钝型、中间型和迟播敏感型。迟钝型品种对播期不敏感,适播期长,冬前≥0℃积温范围为324~560℃,迟播后穗数和产量稳定;中间型品种适播期较长,积温范围为362~566℃,迟播后粒数增加,穗数和产量降低;迟播敏感型品种对播期敏感,适播期较短,积温大于511℃,不宜晚播,晚播后穗数和产量明显下降。在试验地区,推荐小麦适播期为迟钝型品种10月7日至22日、中间型品种10月7日至19日、敏感型品种10月5日至10日。     

Sucrose metabolism in cotton (Gossypium hirsutum L.) fibre under low temperature during fibre development

The effects of low temperature on sucrose content and activities of key enzymes related to sucrose metabolism in cotton (Gossypium hirsutum L.) fibre were investigated. Two cotton cultivars, Kemian 1 and Sumian 15, were grown in the field at two sowing dates in 2006 and three sowing dates in 2007, the differences of environmental conditions during fibre development period (from flowering date to boll opening date) for different sowing dates were primarily on temperature. Low temperatures (MDTmin of 21.1, 20.5 and 18.1 °C) in late sowing dates (25 May/10 June) prolonged the fibre development period, and had significant effect on cellulose synthesis and sucrose metabolism. Results showed that, under low temperature, sucrose content was increased, cellulose content and sucrose transformation rate were decreased, and the variability of cellulose content and sucrose transformation rate through sowing dates in Sumian 15 was more than that in Kemian 1. The measurable activities of sucrose phosphate synthase (SPS), sucrose synthase (SuSy) and acid/alkaline invertases in sucrose metabolism were affected by low temperatures. Under low temperatures, activities of SuSy and invertase in sucrose degradation were increased, and two cultivars had the similar change. In contrast, the activity of SPS in sucrose synthesis was lower than the activity in developing fibre at normal environmental condition, and the time to peak activity was delayed, SPS activity in response to temperatures differed between two cultivars. The results indicated that restrained cellulose synthesis and sucrose metabolism under low temperature were mainly attributed to the changed activities of enzymes (SPS, SuSy and invertase), and the difference of cellulose synthesis and sucrose metabolism in response to temperature in fibre cells for two cotton cultivars was mainly determined by the level of SPS activity.