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1.
Comparative trials with durum-wheat landraces and cultivars in different ecological environments in the mediterranean region
Durum-wheat landraces (local varieties) and cultivars (released varieties) were examined for grain yield and some qualitative traits in three environments in 1985 and 1986. The purpose of this research was the preservation of the local genetic material and its use in durum-wheat breeding programmes in mediterranean countries. It was confirmed that, during the graining period (heading to yellow ripeness), the landraces were more resistant to drought and high temperatures than the cultivars. A short graining period led to a sharp rise in the percentage of protein. On the other hand, the protein content decreased when the grain yield increased. Contrary to the cultivars, the vitrousness of some landraces was not negatively influenced by high soil moisture during the graining period. These landraces combined high grain yield with a high percentage of vitrous kernels and can be considered as valuable gene material for breeding purposes.  相似文献   

2.
Due to economic and ecological factors, European agricultural practices are likely to go towards extensive systems with lower inputs of nitrogen (N) fertilisers. The objective of this study was to assess varietal differences for N use at two nitrogen levels. A set of 20 winter wheat (Triticum aestivum L.) genotypes was studied over 2 years in northern France on a deep loam soil without (N0) and with 170 kg ha−1 N fertiliser (N+) as ammonium nitrate. Results were consistent on both years as the genotype×year or genotype×year×N level interactions were not significant. The genotype×N level interaction was highly significant except for total N utilisation efficiency (total above-ground dry weight/total above-ground N) and grain N concentration. The genotype×N level interaction for grain yield was mainly due to three contrasting genotypes: Cappelle, a cultivar from the 1940s, had the same yield at N0 and N+; Arche had a high yield at both N levels; and Récital had a high yield with added N and a very low one without N. The number of kernels/ear explained most of the variations of grain yield at N0 (48%) and N+ (80%), and of the interaction (67%). N uptake efficiency (total above-ground N/soil N supply) accounted for 64% of the variation in N use efficiency (grain yield/soil N supply), while at N0 and at N+ it accounted for only 30%. N utilisation efficiency (grain yield/total above-ground N) was then more important at N+ than at N0. Grain N explained most of total plant N variation at both N levels. The interaction for N use efficiency was best explained by the interaction of N uptake (63%). The applications of these results to a breeding programme to create varieties adapted to low-input management systems are discussed.  相似文献   

3.
Dry matter production of two different spelt (Oberkulmer, Hercule) and wheat varieties (Arina, Iena) were investigated at two different seeding rates (S1 = 200 grains/m2; S2 = 400 grains/m2) and two nitrogen levels (N1 = 80 kg N/ha; N2 = 110 kg N/ha). The plot experiments were carried out at two contrasting locations (Muri: altitude 459 m asl); Oberwallestalden: altitude 1011 m asl) over three years (1988–1990). In addition nitrogen uptake and the photosynthetic rate of flag leaves was measured. Neither growth regulators nor fungicides were applied. The average grain yield of spelt was 25 % lower than that of wheat (32 % at Muri, 18 % at Oberwallestalden). At the reduced seeding rate (S1) grain weight and grain number per ear was increased by 33 % and 31 %, respectively as compared to the normal seeding rate (S2). The increase of the grain weight and the grain number per ear was larger for the two varieties of spelt (47 % and 42 %, respectively) than for the wheat varieties (23 % and 22 %, respectively). The photosynthetic rate of the flag leaf of spelt and wheat was not significantly different, at the two growth stages measured (anthesis, anthesis + 23 days). Nitrogen yield in the above ground biomass (g N/m2) was not significantly different between spelt and wheat, neither at the beginning of stem elongation, nor at anthesis. At anthesis the nitrogen yield at the reduced nitrogen level (N1) was 16 % and 13 % lower than at the higher level (N2) for spelt and wheat respectively. A higher nitrogen efficiency of spelt under low input conditions was not apparent. Therefore it was concluded that under low input conditions, spelt is not more efficient in dry matter production than wheat. By comparing the “husked” yield of spelt (grains + glumes; representing the trade form) with the grain yield of wheat, spelt is higher yielding than wheat but only at marginal areas of cereal production.  相似文献   

4.
The aim of this investigation was to obtain information about differences between spelt and wheat in relation to their performance under low-input conditions. Two spelt varieties ( Oberkulmer, Hercule ) and two wheat varieties ( Anna, Iend ) were grown at two different seeding rates (S1 = 200; S2 = 400 kernels/m2) and two nitrogen levels (Nl = 80 kg N/ha; N2 = 110 kg N/ha) at two contrasting locations (Muri; altitude 459 m asl; Oberwallestalden: altitude 1011 m asl). No growth regulators and fungicides were applied.
The overall mean for the "husked" yield (grains and glumes) of spelt was not significantly different from the grain yield of wheat. At the higher site Oberwallestalden however, the "husked" yield of spelt was 10.5 % higher than the grain yield of wheat. Although the number of ears per m2 was higher at S2 than at S1, spelt and wheat produced a similar yield at both seeding rates (spelt: S1 = 96 % of S2; wheat: S1 = 95 % of S2) due to the higher single ear weight at S1.
The reaction of spelt and wheat to nitrogen was similar. The yield was 10 % higher at N2 than at Nl for both species. The performance of spelt under low-input conditions was better than for wheat in marginal areas for cereal production only.  相似文献   

5.
T. Presterl    S. Groh    M. Landbeck    G. Seitz    W. Schmidt  H. H. Geiger 《Plant Breeding》2002,121(6):480-486
Maize varieties with improved nitrogen(N)‐use efficiency under low soil N conditions can contribute to sustainable agriculture. Tests were carried to see whether selection of European elite lines at low and high N supply would result in hybrids with differential adaptation to these contrasting N conditions. The objective was to analyze whether genotypic differences in N uptake and N‐utilization efficiency existed in this material and to what extent these factors contributed to adaptation to low N supply. Twenty‐four hybrids developed at low N supply (L × L) were compared with 25 hybrids developed at high N supply (H × H). The N uptake was determined as total above‐ground N in whole plants, and N‐utilization efficiency as the ratio between grain yield and N uptake in yield trials at four locations and at three N levels each. Highly significant variations as a result of hybrids and hybrids × N‐level interaction were observed for grain yield as well as for N uptake and N‐utilization efficiency in both hybrid types. Average yields of the L × L hybrids were higher than those of the H × H hybrids by 11.5% at low N supply and 5.4% at medium N level. There was no significant yield difference between the two hybrid types at high N supply. The L × L hybrids showed significantly higher N uptake at the low (12%) and medium (6%) N levels than the H × H hybrids. In contrast, no differences in N‐utilization efficiency were observed between the hybrid types. These results indicate that adaptation of hybrids from European elite breeding material to conditions with reduced nitrogen input was possible and was mainly the result of an increase in N‐uptake efficiency.  相似文献   

6.
Genotype-by-environment interactions (GEIs) can affect breeding progress because they often complicate the evaluation and selection of superior genotypes. This drawback can be reduced by gaining insights into GEI processes and genotype adaptation. Here, we have studied the GEIs over a set of 24 barley genotypes that were grown across six environments (location-by-year combinations) in Sardinia, Italy. Three groups of genotypes were analysed: barley landraces (LANs), recombinant inbred lines (RILs), and commercial varieties (VARs). The additive main effects and multiplicative interaction (AMMI) model was used for data analysis, and results evidenced no significant differences in grain yield averages for the 24 genotypes. However, there was a relevant GEI for yield mainly between two of the six environments (one characterised by warm pre-anthesis period and high spring rainfalls, and the other characterised by opposite features) and two groups of genotypes (VAR and LAN). Moreover, a negative trade-off between yield levels of genotypes was seen when the barley genotypes were grown in the contrasting environments. Overall, intermediate GEI levels were seen for RILs in comparison to LANs and VARs, and some of the RILs provided valuable yield levels (e.g. RILs 23 and 52). The results thus show the potential usefulness of LANs as a genetic resource for breeding, e.g. to obtain genotypes adapted to Mediterranean environments, such as the RILs analysed in this study. Most of the actual work was carried out when the first author was a PhD student in ‘Agro-meteorology and ecophysiology of agricultural and forest systems’ and she was affiliated to Dipartimento di Scienze Agronomiche e Genetica Vegetale Agraria, Università degli Studi di Sassari, Via E. de Nicola, Sassari 07100, Italy.  相似文献   

7.
It is necessary to clarify the nitrogen (N) demand characteristics with yield levels for wheat after rice in the middle and down reaches of the Yangtze River, which could provide theoretical basis for N fertilizer management. Based-on the multi-years and multi-sites wheat experiments in Jiangsu province, this study constructed the datasets of different yield levels derived from different varieties, N rates, densities, and sowing date experiments. N indicators including N requirement per ton grain (Nreq), dry matter accumulation (DMA), plant N accumulation (PNA), plant N concentration (PNC), straw N concentration (SNC), grain N concentration (GNC), harvest index (HI), N harvest index (NHI) and N nutrition index (NNI) were analyzed. The results showed that there were not significant differences in Nreq among the different yield levels, and the highest Nreq was middle-low yield with 27.8 kg t-1, while the lowest value was 24.8 kg t-1for low yield level. With the increase of yield levels, DMA, PNA and PNC all showed a gradually increasing trend during maturity stage, and there were significant differences among the different yield levels. There was a significant positive correlation between grain yield and PNA, the DMA and PNA increased with the increase of yield in the sowing-jointing stage, jointing-flowering stage and flowering-maturing stage, but the DMA and PNA proportion in different growth stages showed different trends. The SNC and GNC increased with the increase of yield levels. For SNC, there was no significant difference between the high yield and middle yield level, but it was significantly higher than the low-middle and low yield level. For GNC, there were significant differences among different yield levels except for the middle and low-middle yield level. The HI increased gradually with the increase of the yield levels, and its range was 0.39-0.49. The HI for low-middle and low yields were significantly lower than that of middle and high yield levels, while there were not significant differences in NHI among different yield levels. Its variation range was 0.60-0.96. The NNI gradually increased with the increase of the yield levels, and there was significant difference between different yield levels. The NNI of the high-yield level was higher, and some of the values were greater than 1 which indicating that some experiments had excessive nitrogen fertilizer supply. With the increase of the yield level, the Nreq increased first and then decreased, while the DMA, PNA, PNC, SNC, and GNC were gradual increased. The increase of SNC was higher than the GNC, therefore, the extravagant absorption of N by wheat should be avoided in field management. The variation ranges of the HI and NHI were consistent with previous studies. The higher DMA and PNA in the late growth stages were the main reasons for the high yield of wheat. The NNI could be a promising indictor in the field N management of wheat.  相似文献   

8.
为进一步揭示硝酸还原酶(nitrate reductase, NR)活性的调控机制及其与植株体内硝酸盐含量的关系。本试验在正常供氮(15 mmol L–1 NO3–)和缺氮(7.5 mmol L–1 NO3–)条件下, 以氮高效(H1:742和H2: Xiangyou15)和氮低效(L1: 814和L2: H8)油菜基因型为研究材料, 通过NR活性的专性抑制剂处理, 研究NR活性和硝酸盐含量的基因型和氮水平差异。结果表明, NR专性抑制剂处理可以显著降低叶片NR活性, 正常供氮和缺氮条件下分别降低53.0%和57.6%, 但对叶片硝酸盐的含量没有显著影响。正常供氮条件下的NR活性和硝酸盐含量比缺氮条件下分别高46.9%和16.4%。氮高效油菜基因型的硝酸盐含量显著低于氮低效基因型。H2的NR活性(NRAact)显著高于氮低效基因型的本质原因是其主效基因(nia2)的相对表达量高于氮低效基因型。本研究充分表明NR活性和硝酸盐含量存在明显的基因型和氮水平差异, 一定程度的NR活性变化对植株体内硝酸盐的含量并没有显著的影响。  相似文献   

9.
对52份四川甘蓝型油菜地方种和24份四川推广品种作了收获前种子发芽试验,研究了四川甘蓝型油菜的休眠特性。结果表明四川甘蓝型油菜品种间的休眠期差异达显著水平,抗收获前发芽资源数量少;地方种与推广品种间发芽指数差异不显著,但发芽率和发芽指数的变幅及分布差异达0.05显著水平,四川甘蓝型油菜推广品种发芽指数的分布较地方种更集中于低和高的范围内;根据材料发芽进程和发芽指数进行聚类分析,将推广品种聚为三类：第一类为第1天发芽高峰类型,第二类为第1、2天发芽高峰类型,第三类为抗收获前发芽类型;地方种聚为四类,比推广品种多一种类型：第1、2天发芽高峰类型。鉴定筛选的四川甘蓝型油菜抗收获前发芽的宝贵资源及其休眠特性,将为甘蓝型油菜的抗收获前发芽生理研究和育种提供信息和材料。  相似文献   

10.
A field experiment was conducted with different nitrogen regimes to assess the growth and yield performance of wheat genotypes which differ in nitrate assimilation potential. Genotypic differences in biomass accumulation were observed at different growth stages. The nitrogen treatment had little effect on biomass accumulation at early stages of growth, while at later stages of growth there was enhanced biomass accumulation when N was applied in more than two splits. On an average, genotypes with high nitrate reductase activity (the 'HNR' genotypes) accumulated 14.2 % more biomass than the genotypes with low nitrate reductase activity ('LNR' genotypes) when an extra dose (40 kg N ha−1) of nitrogen was given at the time of anthesis. The application of nitrogen in more than two splits increased grain yield of both 'HNR' and 'LNR' genotypes mainly by increasing grain weight per ear. The application of an extra dose of nitrogen (40 kg N ha−1) at the time of anthesis increased grain yield of 'HNR' genotypes by 38.5 % as compared to 'LNR' genotypes.  相似文献   

11.
Summary One set of 285 genotypes from three landraces and one natural population and a second set of 165 genotypes from two landraces and one natural population were evaluated in separate trials. Variation among populations was mostly accounted for by the difference between landrace and natural population genotype groups, the former showing features related to higher seed yield and short-term aerial dry matter (DM) yield and to lower persistence, cold tolerance and protein content. Compared to variance among ecotypes, that within ecotypes was never lower and it was at least four-fold higher for important traits such as aerial and total (aerial plus stolon) DM yield, stolon density, production of seed heads and cold tolerance. Landraces and natural populations showed similar levels of intra-population variation for all traits except cold tolerance, for which landraces tended to somewhat greater variation. Trait associations were less definite at the genotype level than what previously found in terms of mean values of the ecotypes. This finding and the relatively high broad sense heritability which was observed for all components of DM and seed yield can support the breeding activity on this clover. The level of variation and of heritability found for protein content do not suggest the routine evaluation of this trait in breeding programmes.  相似文献   

12.
Drought strongly influences potato (Solanum tuberosum) production and quality. Potato being a drought susceptible crop, the development of varieties with enhanced tolerance to water stress could highly improve productivity in drought prone areas. The objective of this study was to evaluate the ability of several yield based indices to be used in large scale screening for drought tolerance. The experiment included improved varieties, genetic stocks and landraces potatoes grown under drought and irrigated conditions. A group of accessions with high yield under both conditions was identified. Mean productivity (MP), geometric mean productivity (GMP), tolerance (TOL), drought tolerance index (DTI), drought susceptible index (DSI) and yield stability index (YSI) were calculated from tuber yield under drought and irrigated conditions. The relationships between these indices and yield were analyzed. The Fleiss’ Kappa concordance test was used to analyze the correspondence between accessions previously identified as highly productive under both drought and irrigated conditions and accessions with optimal values for the different indices. MP, GMP and DTI allowed identifying genotypes combining high yield potential and high yield under drought within the three subsets of genotypes. Conversely, DSI, YSI and TOL showed low and variable concordance values across subsets, suggesting that their efficiency in screening genotypes highly depends on the nature of the tested genetic material.  相似文献   

13.
茄子氮效率基因型差异的研究   总被引：2，自引：0，他引：2  
为了解茄子的氮素吸收利用特性和筛选氮高效基因型,采用田间小区试验和测试分析方法,通过测定茄子产量、氮利用效率、氮响应度和氮素吸收总量等指标,对10个茄子基因型进行了氮效率方面的研究。结果表明,不同基因型茄子的产量、氮利用效率、氮响应度和氮素吸收总量均存在显著差异。根据供试材料在施氮和不施氮处理下氮效率的不同将供试10个基因型划分为5种类型:高氮高效-低氮高效型(HH-LH)包括06-991;高氮高效-低氮中效型(HH-LM)包括06-917;高氮高效-低氮低效型(HH-LL)包括06-961和06-867;高氮中效-低氮低效型(HM-LL)包括06-972,06-947,06-854,06-830和06-909;高氮低效-低氮低效型(HL-LL)包括06-910。对氮效率构成因素通径分析表明,氮素吸收总量对氮效率的直接作用大于氮利用效率的直接作用,氮素吸收总量是决定氮效率的主要因素。  相似文献   

14.
Summary The new European Common Agricultural Policy and environmental considerations are certainly to change agricultural practices toward low input cultivation systems. Nitrogen is one of the main inputs of winter wheat in northern France and it contributes highly to phreatic water pollution. A research programme has then been set up in order to study whether it is possible to breed for winter wheat cultivars using more efficiently N fertilisers. Less nitrogen would be applied, decreasing pollution risks and operational costs. It has been shown that a large variation exists for N related traits and for the resistance against N deficiency. On the one hand the cv Arche is very resistant to N deficiency, its yield on low N conditions (with no N fertiliser) is on average 89% of its yield on high N conditions (with a high N application). On the other hand, cv Récital is very susceptible to N deficiency as this same percentage is only 61%. A study on 10 hybrids showed that heterosis for grain yield was higher at low N level than at high N level. This was due to a higher number of grains per m2.  相似文献   

15.
施氮对不同基因型玉米籽粒发育和氮效率的影响   总被引：2，自引：0，他引：2  
为解决生产中氮肥过度施用造成的资源浪费和环境污染问题,选择适宜的玉米氮高效品种至关重要。在不同施氮水平下,对不同基因型玉米籽粒发育及氮效率的差异进行了比较,采用田间试验,对屯玉99(TY)、潞玉19(LY)、先玉335(XY)3个玉米品种在4个施氮水平N0、N1、N2、N3(0,80,160,240 kg/hm2)条件下的籽粒发育和氮效率进行对比分析。结果表明,各品种玉米的籽粒干质量与氮含量差异在N3水平下最大,依次表现为N3N2N0N1;随着施氮量的增加,双高效型先玉335和高氮高效型屯玉99籽粒发育速率加快,籽粒干质量和籽粒氮含量在各生长时期都有明显增加,增施氮肥可以有效提高其氮肥利用率,促进氮在玉米植物体内的转移;低氮高效型潞玉19在低氮(N0、N1)水平下保持较高的产量,但随施氮量的增加,其籽粒干质量和氮含量无明显变化,产量甚至有所降低,导致氮利用效率降低。双高效型先玉335在低氮和高氮条件下都有较好的产量,是适合广泛种植的玉米品种;低氮高效型潞玉19适合在贫瘠土壤和施氮条件不良的条件下种植。  相似文献   

16.
Western Europe is the world's greatest leek producing and consuming region. Belgium is situated in the centre of Western Europe and can be considered as a genepool of landraces of leek. Although the commercial varieties nowadays take over the successes of Belgian landraces, this paper deals with the breeding potential of the Belgian landraces. Typing the Belgian landraces was done in an observation trial together with 50 cultivars. Clustering analysis revealed that 4 of the Belgian landraces were autumn types, 2 landraces were of the early winter type and another 12 landraces were ranged with 6 commercial varieties to form the most winterhardy group of leek. For the important characteristics leaf colour and senescence resistance, the Belgian landraces were better than most of the commercial varieties. Although, for economically more important characteristics shaft length and some disease resistance they scored low. Finally, in this trial, the Belgian landraces were high yielding, especially in the late season. But also in the early season (harvest in September and November) some Belgian landraces were in the top 10 for yield. At harvest in February 9 of the 10 best yielding winterleeks were Belgian landraces. This proves that the Belgian landraces were well adapted to the soil and climate of this region. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
为了筛选综合性状较好的可用于小麦品质改良的农家种资源,以212份小麦农家种为材料,采用Vp1B3分子标记和田间喷雾进行了抗穗发芽鉴定,用硬度指数法进行了硬度测定,并考察了部分农艺性状。结果表明,212个农家种中Vp-1Ba（感穗发芽）、Vp-1Bb（抗穗发芽）和Vp-1Bc（抗穗发芽）基因型的频率分别为70.28%,6.16%,23.70%,以Vp-1Ba基因型为主。3种基因型穗发芽率差异不显著,212个农家种的穗发芽率在7.79%~28.56%之间,平均为15.28%;农家种硬度指数(HI)平均值为71.22;农家种平均株高达到113.46 cm;农家种对白粉病抗性变异丰富,有3个品种为白粉病免疫;农家种平均穗粒数为28.33,平均千粒重为30.96 g。针对抗穗发芽、籽粒硬质、株高适宜、抗白粉病、高产等育种目标,筛选出等‘金包银’、‘玉麦1’、‘大红芒2’等12个种质材料,为进一步培育优质小麦奠定了基础。  相似文献   

18.
There is renewed interest in wheat landraces as important sources of genetic variation for agronomic characters. Fifty-three pure lines of bread wheat (Triticum aestivum L.) derived from seven landraces collected from southeastern Iran were used to estimate genetic variation and heritability for 13 developmental and quantitative characters. Path-analysis was used to partition the genetic correlations between grain yield and six grain yield-related traits. Mean values of landraces were also compared with three improved cultivars from California and Iran. Genotypic differences among the landraces and among the pure lines collected from the landraces were highly significant for all characters considered. Compared with the modern cultivars, the landrace genotypes were, on average, later in days to heading and taller than the cultivars but had lower values for number of grains per spike, 1000-grain weight, grain yield and harvest index. Some landrace genotypes were similar to the modern cultivars for grain yield. Moderate to high genetic variation was displayed by number of grains per spike, number of spikes per plant, 1000-grain weight, and harvest index. The heritability estimates ranged from 59% for grain yield to 99% for days to anthesis. Expected genetic advance (as % of the mean) was ≈34% for number of spikes per plant, number of grains per spike, and 1000-grain weight. Days to heading and to anthesis correlated positively with number of spikes per plant, shoot biomass, and straw biomass but negatively with number of grains per spike and harvest index. The strong direct effect of number of spikes per plant on grain yield was completely counterbalanced by its indirect negative effects via number of grains per spike and 1000-grain weight. Number of grains per spike and 1000-grain weight were positively correlated with grain yield, and they had large direct effects. These two characters, however, were negatively correlated and exhibited a substantial counterbalance effect via one another and via number of spikes per plant. The landraces could be improved by intercrossing the promising genotypes identified in this study, with simultaneous selection for earliness, fewer number of spikes per plant, greater number of grains per spike and heavier grains. For further improvement, crossing programs between the landraces and introduced germplasm may be necessary. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.
棉花抗枯黄萎病品种耐低磷种质筛选   总被引：3，自引：1，他引：2  
 采用蛭石栽培和营养液浇灌的方法,研究棉花品种耐低磷筛选指标,利用这些指标对88份棉花抗枯、黄萎病品种进行磷素利用率极端基因型的筛选。结果表明,株高和根冠比在不同品种和不同磷浓度处理之间无显著差异,而棉苗干物重、地上部鲜重、总叶面积、叶绿素含量、地上部干物重及磷利用率在不同磷浓度处理和不同品种之间均存在显著差异,可以作为棉花苗期耐低磷能力的评价指标。利用这些指标对棉花抗枯、黄萎病品种进行了分析。聚类结果将88个品种主要分为耐低磷基因型和非耐低磷基因型两大类,分别包括25个和55个品种。其中,中棉所21、中99和陕棉11属于耐低磷的极端基因型。  相似文献   

20.
Summary The objective of this study was to evaluate traits which can facilitate and improve selection for grain yield of spring barley. Five experiments were conducted in different environments to measure grain yield and yield related traits of breeding lines and exotic varieties. Differences for rate of canopy expansion were significant and offer the opportunity to select for a high weed suppressing potential but there was no relation to grain yield. Dry matter yield/m2 at anthesis and its water-soluble-carbohydrate content were not correlated with grain yield/m2 and number of grains/m2. Variation in biomass among breeding lines with a similar development and plant height was small. Biomass standardized for plant height was stable across environments and showed a good correlation with number of grains and grain yield. The contribution of pre-anthesis assimilation to grain yield was only important under low yielding experimental conditions, but the differences among the genotypes for this trait were inconsistent. It may be difficult to select genotypes with a high potential contribution of pre-anthesis assimilation to grain yield.  相似文献   

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