温光互作对不同生态型小麦品种发育效应的研究：Ⅰ.品种最长,最短…

试验在温光互作设计下，通过品种苗穗期（出苗－抽穗）对温光反应的变异分析看出，不同类型品种在不同温光组合下，不仅存在着最短与最长的苗穗期，而且不同类型品种，对温光反应类型不同，春性类型品种对春化基本无反应而对 光长反应敏感；强冬性类型品种对春化反应敏感，而对光长必须在一定春化量基础上才表现敏感，并且具有短日代替春化效应。一般冬性类型品种（主要指黄淮麦区的半冬性过渡类型）多为温光兼敏性，无短日春化特性     

温光互作对小麦品种发育效应的研究——Ⅱ.温光对品种苗穗期作用力与回归分析

通过品种对温光互作反应的作用力分析和回归分析,看出供试的南方北方17个品种可分为光敏感类群(春性,强春性),温敏感类群(冬性、强冬性),温光兼敏感类群(半冬性)。在具有不同程度春化效应的品种中,温光作用的先后也有三种类型,即春化光照并进型(半冬性),春化半提前型(冬性,强冬性),春化提前型(超强冬性、春化要求60天以上的晚熟品种)。     

中外小麦品种光温互作效应比较研究

来源不同的参试冬小麦品种 (春小麦品种 )具有对春化 (日长 )反应敏感性远大于对日长(春化 )反应的一般特征。但英国冬小麦兼有中国超强冬性品种的短日效应和冬性品种的春化累积量 ;美国冬性品种则兼有中国强冬性品种的春化累积量和冬性品种的长日反应特性。英、澳春性小麦对春化作用也有微弱反应 ,类似中国南方冬播春性小麦。中国中熟冬麦区温光条件与英美品种温光特性的差异是引种生育期较长、成熟偏晚的主要原因     

温光互作对小麦品种发育效应的研究 Ⅱ.温光对品种苗穗期作用力与…

通过品种对温光互作反应的作用力分析和回归分析，看出供试的南方北方１７个品种可分为光敏感类群（春性，强春性），温敏感类群（冬性，强冬性），温光兼敏感类群（半冬性）。在具有不同程度春化效应的品种中，温光作用的先后也有三种类型，即春化光照并进型（半冬性），春化半提前型（冬性，强冬性），春化提前型（超强冬性、春化要求６０天以上的晚熟品种）。     

中外科品种光温互作效应比较研究

来源不同的参试冬小麦品种（春小麦品种）具有对春化（日长）反应敏感性远大于对日长（春化）反应的一般特征,但英国冬小麦兼有中国超强冬性品种的短日效应和冬性品种的春化累积量;美国冬性品种则兼有中国强冬性品种的春化累积量和冬性品种的长日反应特性。英、澳春性小麦对春化作用也有微弱反应,类似中国南方冬播春性小麦。中国中熟冬麦区温光条件与英美品种温光特性差异是引种生育期较长、成熟偏晚的主要原因。     

不同生态类型小麦品种田间春化的温光特性研究

通过连续3年的小麦生态试验研究发现不同类型小麦品种田问春化的温光特性有质的区别，春型品种不存在光温特殊要求，对温光适应范围很宽，半冬型品种存在低温春化阶段发育现象，但对光照长短无明显要求，冬型品种对温光要求范围较窄，有明显的低温长日照要求。     

小麦发育温光效应的模拟研究

在室内人工控制条件下,对17个不同类型的小麦品种进行低温春化处理(0,10,20,30,40,50,60,70天)和光长处理(6,10,14,24小时)试验.初步揭示了温、光对供试品种的单独效应规律.提出了高温与光长对小麦品种的离析作用,解释了不同品种的自然生态适应性,进一步明确了品种对温光反应是一种数量累积效应,并根据数量变化的量与质的关系进行了断截分类.     

以光周期处理与分期播种试验综合鉴定大豆品种的光温反应

设置短日照(12 h)和长日照(16 h)两种光周期处理,并以春播模拟低温、夏播模拟高温条件,形成长日+低温、长日+高温、短日+低温、短日+高温4种光温组合。2007年对近年育成的10个北方春大豆[Glycine max (L.) Merr.]品种(系)和18个黄淮海夏大豆品种(系)进行了光温反应特性鉴定。2008年对50份材料进行了光周期反应鉴定。结果表明,不论在低温(春播)还是高温(夏播)条件下,短日照均加快大豆的发育进程,导致开花提前;不论在长日照还是短日照条件下,高温均减少出苗至初花的日数。光周期和温度对大豆的发育存在明显的互作,随着温度的升高,短日照促进大豆发育的效应有所加强;随着日照的缩短,高温加快发育的作用也有所增大。供试大豆品种生态类型在光周期反应敏感度(PRS)、温度反应敏感度(TRS)及光温综合反应敏感度(PTCRS)等方面均存在显著差异。北方春大豆品种的上述3个指标均小于黄淮海夏大豆品种,但前者在不同光照条件下的温度反应敏感度差值和在不同温度条件下的光周期反应敏感度差值均较后者高,说明北方春大豆品种光温互作效应较强。     

小麦品种温光效应与主茎叶数的关系

小麦主茎叶数是器官建成生长发育年龄的重要标志。因此,小麦温光反应特性的差异,除表现在穗部器官建成速度与抽穗速度外,还集中表现在主茎叶片数上。研究表明主茎叶数的变异受品种遗传及温光环境的影响。在人工控制春化和光照条件下,所有供试品种的最少叶数十分接近于春性小麦的最少叶数,表明春性品种可能是小麦冬春性进化的     

小麦的穗分化与温光反应

1982—1985年在北京地区的小麦多期播种试验中,强春性小麦在三叶期开始了穗分化的伸长期.随着冬性的增强,伸长期的主茎叶数逐渐增多,天数也逐渐增加.强春性品种的穗分化对温度和日长都无严格要求,高温可促进分化.冬性品种的穗分化可在温度较低、日长较短逐渐转入温度较高、日长较长的条件下顺利进行.过渡类型小麦穗分化的温光条件居中.伸长期或二棱末期是过渡类型和冬性小麦完成春化反应的标志.     

Relationship between cold resistance,heading traits and ear primordia development of wheat cultivars

Summary For breeding early heading wheat cultivars with resistance to frost damage which are well adapted to dry areas of West Asia and North Africa, the relationships between winter hardiness, ear primordia development and heading traits, i.e. veernalization requirement, photoperiodic response and narrow-sense earliness, were assessed using a total of 30 genotypes of wheat (Triticum aestivum L.) grown in an experiment in Syria. The results of artificial freezing tests indicated that cultivars with good winter hardiness were to be found only in the winter wheat cultivars which required 50 or more days of vernalization treatment. These winter wheat cultivars did not initiate internode elongation without vernalization even at 95 days after planting. Thus their ear primordia were still underground and were protected from frost injury at this stage. Photoperiodic response and narrow-sense earliness were not associated with winter hardiness and earliness of internode elongation, but were related to the number of days to heading after planting. This indicated the possibility for breeding early heading cultivars with winter hardiness and tiller frost avoidance by combining high vernalization requirement, short narrow-sense earliness and neutral response to photoperiod.     

Measurement of response to vernalization in Australian wheats with winter habit

Summary Development in wheat is strongly controlled by sensitivity to vernalization and photoperiod, and to a lesser degree by non-vernalizing temperature and intrinsic earliness. A method to measure effect of vernalization in wheats with winter habit is described. Twenty seven wheats with winter habit and eight with spring/facultative habit were studied, comprising breeding lines and cultivars with maturities suited to south-central New South Wales. Effect of vernalization on the development of these wheats was quantified by integrating responses to vernalizing treatments of differing duration. Intrinsic earliness was measured as time for vernalized seedlings to grow to ear emergece in an 18h photoperiod with day/night temperature of 21/16°C, and response to photoperiod as the difference in time to ear emergence between 9 and 18h daylengths. Integrated response to vernalization is sensitive to both cumulative and thresh-hold responses and is applicable to wheats of all habit type. Integrated response to vernalization and intrinsic earliness were positively associated within wheats with winter habit. Wheats were largely of restricted origin, so that there were few allelic differences at Vrn loci to disrupt this association, which suggests intrinsic earliness may modify response to vernalization. Though integrated response to vernalization was measured with artificial treatments, it was strongly associated with ear emergence for wheats with winter habit when grown at a site in New South Wales.     

The impact of vernalization requirement,photoperiod sensitivity and earliness per se on grain protein content of bread wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.)

In wheat, a shorter pre-anthesis phase is often associated with increased grain protein content (GPC) but decreased grain yield. Cultivar differences in pre-anthesis development are mainly determined by vernalization requirement, photoperiod sensitivity and earliness per se. This research examines whether cultivar differences in these traits affect GPC, especially whether the three traits can partially explain genotype × environment interactions for GPC. Twenty-four winter wheat and five spring wheat cultivars selected from International Winter Wheat Performance Nursery (IWWPN) trials and 12 winter wheats tested over 2 years in Germany were characterized using the CSM-Cropsim-CERES-Wheat model. The model parameter P1V specifies the cultivar vernalization requirement, P1D the photoperiod response, and P₁₂₃ earliness per se. Covariance analyses of the IWWPN dataset indicated that about 7% of variation in GPC was explained by cultivar, with another 7% attributable to interactions of cultivar with region, site and year. P1V, P1D and P₁₂₃ all influenced GPC, but their effects varied with region, site and year. For example, for two regions, the effect of P1V on GPC decreased with latitude. Path analyses using the data from Germany confirmed that GPC increased with earlier anthesis, which was influenced by P1D and P₁₂₃. Lack of an effect of P1V at this location presumably was due to all cultivars being completely vernalized. The results indicate that efforts to improve GPC could target the three traits to specific populations of environments, which should reduce the large influence of environment on GPC.     

Effect of vernalization and photoperiod on flax flowering time

Vernalization and photoperiodism are two important physiological processes related to yield of many cool-season annual crops. The flowering response of 20 flax (Linum usitatissimum L.) genotypes to two vernalization regimes (vernalized and unvernalized) and two photoperiod treatments (10 and 14 h) was evaluated in a growth chamber study in 2010 and 2011. The results suggest that photoperiod, vernalization, and genotype all had an effect on earliness as measured by days to anthesis. Unlike flax grown in the Upper US Midwest and Canada, Texas flax is grown in the fall due to high spring and summer temperatures. Genotype interaction was observed with both vernalization and photoperiod. Specifically, flax genotypes from Texas (winter type) were sensitive to both vernalization and photoperiods for flowering. Texas genotypes delayed anthesis for 7 days or more in unvernalized seedlings, whereas flowering time of most other spring grown flax genotypes was unaffected by the vernalization treatments. Texas genotypes also delayed anthesis for 12 days or more under vernalized and short day conditions, whereas most other genotypes were not influenced by photoperiodism in vernalized seedlings. The selection for vernalization and photoperiodic sensitivity in Texas genotypes and introgression of these traits into recently adapted spring grown genotypes is needed for development of high yielding flax genotypes for southern Great Plains production areas.     

Winter Hardiness, Frost Resistance and Vernalization Requirement of European Winter Oilseed Rape (Brassica napus var. oleifera) Cultivars within the Last 20 Years

Cultivars of European winter oilseed rape cultivated in the second half of the 1970s and in the mid-1990s were screened for their winter hardiness, frost resistance and vernalization requirement. A strong correlation between winter hardiness and frost resistance in both groups of rape has been noticed. Among oilseed rapes cultivated in the late 1970s, low erucic acid and particularly double zero cultivars were less winter hard than high erucic acid cultivars. Double zero cultivars were characterized by lower frost resistance and lower vernalization requirement. A significant correlation between vernalization requirement and both frost resistance and field survival has also been shown. Frost resistance of the 1990s (double zero) cultivars was higher than that of double low cultivars from the late 1970s. Their vernalization requirement was still small and did not correlate with either frost resistance or winter hardiness. It was concluded that reduction in the content of glucosinolates in the 1970s involved decrease in winter hardiness and vernalization requirement of cultivars. During the following 20 years winter hardiness of double low cultivars has been improved, but vernalization requirements have not changed. As a result no correlation between winter hardiness and vernalization requirement in contemporary canola cultivars has been observed.     

Variability in the Duration of Stem Elongation in Wheat Genotypes and Sensitivity to Photoperiod and Vernalization

The stem elongation phase in wheat [Triticum aestivum (L.)] is considered critical for yield determination. A longer duration of this phase could hypothetically increase grain set and therefore yield. Genetic variation in the relative duration of the stem elongation phase having been reported, the aim was to pinpoint whether this variability was associated with sensitivity to photoperiod, vernalizing temperatures or to differences in intrinsic earliness. Pairs of cultivars identified as having different duration of the stem elongation phase (from the appearance of the first visible node to anthesis) were grown under natural (short) or extended photoperiod, with or without vernalization. Variability in the duration of this phase, in the cultivars analysed, was related to different sensitivity to photoperiod, while differences in the previous phases were related to sensitivity to both photoperiod (though different to the sensitivity of the following phase) and vernalization.     

The influence of a spring habit gene, Vrn-D1, on heading time in wheat

The adaptability of wheat cultivars to environmental conditions is known to be associated with a vernalization requirement, that is, spring/winter habit. To clarify the genetic effect of the spring habit gene, Vrn‐D1, on heading time in the field, recombinant inbred lines (RILs) with or without the Vrn‐D1 gene were produced from F₂ plants of the cross between ‘Nanbukomugi’ and ‘Nishikazekomugi’, non‐carrier and carrier cultivars of this gene, respectively. Using growth chambers with a controlled temperature and photoperiod, three components of heading time, i.e. vernalization requirement, photoperiodic sensitivity and narrow‐sense earliness (earliness per se), were evaluated in each RIL. RILs with the Vrn‐D1 gene (E lines) showed greatly reduced vernalization requirements and slightly shorter narrow‐sense earliness than RILs without Vrn‐D1 (L lines), although no difference in photoperiodic sensitivity was observed between the two groups. RILs were planted at four different sites in Japan and examined for their heading time in the field. E lines headed significantly earlier than L lines at all locations, indicating that the earliness of E lines is stable in various environmental conditions. These results indicated that spring habit caused by Vrn‐D1 gene, as well as narrow‐sense earliness, was responsible for heading time in the field.     

春化、光周期和矮秆基因在不同国家小麦品种中的分布及其效应

为促进国外种质资源在我国的有效利用,将14个国家的100份代表性小麦品种在国内的8个代表性地点种植,调查抽穗期、成熟期和株高,并以4个春化基因(Vrn-A1、Vrn-B1、Vrn-D1和Vrn-B3)、1个光周期基因(Ppd-D1a)及2个矮秆基因(Rht-B1b和Rht-D1b)的分子标记检测所有品种的基因型。春化基因Vrn-A1a、Vrn-B1、Vrn-D1和vrn-A1+vrn-B1+ vrn-D1的分布频率分别为8.0%、21.0%、21.0%和64.0%;显性等位变异Vrn-A1a、Vrn-B1和Vrn-D1主要存在于来自中国春麦区及意大利、印度、加拿大、墨西哥和澳大利亚的品种中,这些品种一般为春性类型;春化位点均为隐性等位变异或vrn-A1+vrn-D1+Vrn-B1的品种主要分布在中国冬麦区、美国冬麦区、俄罗斯冬麦区,以及英国、法国、德国、罗马尼亚、土耳其和匈牙利,这些地区的小麦均为冬性类型。秋播时,供试品种均能正常抽穗,且携带春化显性变异的材料较隐性类型抽穗早,显性等位变异表现加性效应,4个春化位点均为隐性变异的一些欧美材料因抽穗太晚在杨凌和成都不能正常成熟;而春播时,显性等位变异基因型抽穗的频率高,隐性等位变异基因型基本不能抽穗。光周期不敏感基因Ppd-D1a的分布频率为68.0%,主要分布在中国、法国、罗马尼亚、俄罗斯、墨西哥、澳大利亚和印度,而光周期敏感等位变异Ppd-D1b主要分布在英国、德国、匈牙利和加拿大等中高纬度地区;携带Ppd-D1a的品种较携带Ppd-D1b的品种抽穗早,大多数Ppd-D1a品种在长日照和短日照条件下均能成熟,大部分Ppd-D1b品种在短日照条件下不能成熟。Rht-B1b和Rht-D1b基因的分布频率分别为43.0%和35.0%,其中Rht-B1b主要分布于美国、罗马尼亚、土耳其、意大利、墨西哥和澳大利亚,Rht-D1b主要分布于中国、德国、英国、意大利和印度。一般来说,一个国家的品种携带Rht-B1b或Rht-D1b之一,而这2个基因在高纬度地区分布频率较低。Rht-B1b、Rht-D1b和Ppd-D1a的降秆作用均达显著水平,Rht-B1b和Rht-D1b的加性效应突出。