Heterosis and hybrid performance in topless faba beans (Vicia faba L.)

Parental lines, F₁ and F₂ hybrids from a 7×7-diallel of topless faba beans and eight standard cultivars were grown in single-rows for two years at four sowing dates on a highly fertile loam soil near Göttingen. In grain yield, F₁ hybrids showed 21 to 54% advantage over the higher yielding parent. Compared with the midparental value an average heterosis of 50% was observed for grain yield. Corresponding heterosis mean values ranged from 3 to 37% for yield components and up to 11% for phenological traits. The grain yield of the highest yielding topless F₁ hybrid was equal to that of Alfred, the highest yielding indeterminate standard cultivar. High grain yield in the topless hybrids was closely correlated with high biomass yield, late ripening and tall plants generally having a high number of podded nodes and pods on the main stem. Due to their agronomic advantages, i.e., lower plant length, reduced lodging sensitivity and earlier ripening, efforts at breeding topless hybrids seemed to be worth-while in faba beans. However, their yielding ability must be improved further before they can compete with normal, semi-dwarf and stiff-strawed cultivars.     

Rate and inheritance of cross-fertilization in faba bean (Vicia faba L.)

Summary To assess the feasibility for synthetic varieties of Vicia faba L., 108 faba bean genotypes were screened for cross-fertilization rate in five field experiments carried out in 1989 and 1990 at Wageningen.Significant genotypic differences were observed for outcrossing rate, which ranged from 1 to 55%. These percentages, however, are thought to be not high enough for a commercially feasible production of synthetic varieties.The inheritance of cross-fertilization rate, determined by testing the F₄ generation of a cross between two inbreds, both with high outcrossing rates, appeared to be of a polygenic nature, as was indicated by the wide variation in, and the continous distribution of, the cross-fertilization rates. Among the F₄ lines tested some had a significantly higher cross-fertilization rate than the parents. However, this difference was not found when these lines were retested, indicating that possibilities for successful selection for higher outcrossing rates might be limited.     

Study on the Inheritance and Relationship of Some Morphological and Fertility Characters in Faba Bean (Vicia faba L.)

Inheritance of several morphological and fertility characters was studied in F2 generation of two sets of diallel cross, using Griffing's analysis of variance. A paramount importance of general combining ability (GCA) over specific combining ability was measured for most studied characteristics. Correlations among GCA values for seed yield, morphological and fertility characters do not give a clear definition of the plant ideotype. “Terminal inflorescence” character appeared to reduce the seed per ovule ratio. Higher additive component was found for the ovule per pod than for seed per pod characters.     

Heterosis and inheritance of drought tolerance in faba bean, Vicia faba L.

Twelve parental lines of faba beans and 27 F₁ hybrids derived from them were field-tested under a dry and a well-watered treatment, at two German locations (Göttingen, Hohenheim) in two years (1995, 1996). Drought was artificially induced using rain shelters from anthesis until maturity. Data were collected on yield under dry (Yd) and well-watered (Yw) conditions. Drought tolerance was assessed as Yd/Yw. The mid-parent heterosis was significant for Yd and Yw, but not for Yd/Yw. Relative heterosis for Yd (52.0%) was greater than for Yw (39.3%). Parental heritability was greater for Yw (0.86) than for Yd (0.61). However, it was similar for both traits in F₁ hybrids (0.65 and 0.66). Principal component analysis showed that F₁ hybrids exhibited the same pattern of adaptation as their parents. The heritability of drought tolerance was 0.48 in F₁ hybrids and 0.70 in parents. Attention should be paid to its negative correlation with yield. Several hybrids combined high tolerance, a favourable pattern of adaptation and appropriate performance.     

Pollination,fertilization and seed development in winter stocks of faba beans (Vicia faba L.)

Summary Incidences of pollination and fertilization were determined in five stocks of winter bean (two populations, two inbred lines, one cultivar) in two years. In the second year, irrigation was included as an experimental treatment and the development of seeds was monitored. Large differences between years were found in the measures of pollination and fertilization, and irrigation was associated with a small but significant increase in the proportion of ovules which were fertilized within fertilized flowers, particularly in the ovules furthest from the stigma. This increase was clearly reflected in the corresponding indices of seed maturation in the irrigated plants. Irrigation was not associated with any change in the proportion of ovules which aborted. Small but statistically significant differences in all of the measures of pollination and fertilization were found among the stocks. It is suggested that the variation in the incidences of pollination and fertilization was largely associated with variation in the synchrony of anthesis within racemes. The proportion of ovules within pods which matured as seeds and the proportion which aborted both varied significantly among the five stocks. Abortion appeared to act independently of fertilization in affecting the index of seed maturation, so both mechanisms should be considered when breeding for improved filling of pods.     

Inheritance of seedling colour in faba bean (Vicia faba L.)

Summary The inheritance of purple seedling colour was studied, in relation to the genetic control of flower colour. It was found that purple seedling colour is likely to be controlled by a single gene and that the trait is dominant over green seedling colour. White flowering prohibited the expression of the purple seedling colour, and is therefore thought to be epistatic.This character can be used to estimate rate of outcrossing in breeding programmes, as well as contribute to our knowledge of the biosynthesis of plant pigments and secondary metabolites such as tannins.     

Comparison of intra- and inter-pool crosses in faba beans (Vicia faba L.). II. Genetic effects estimated from generation means in Mediterranean and German environments

Genetic diversity between parents is important for hybrid breeding and for maximum usefulness of a cross in pure line breeding. However, wide crosses may suffer from poor adaptation in the target environments and recombination losses owing to disruption of favourable epistatic gene combinations. In this study we investigated the importance of various gene effects for different traits in the parents and generations F¹ to F⁵ derived from 99 intra- and inter-pool crosses among 20 lines of the Minor, Major, and Mediterranean germplasm pools of faba bean in Mediterranean and German environments. Yield performance of parental inbreds and progenies of crosses in different selfing generations was high in the region of adaptation of the respective germplasm pool. Heterosis for yield was greatest in interpool crosses of Minor × Mediterranean germplasm, amounting to 106% in Mediterranean and 72% in German environments. Interpool crosses exhibited significantly greater heterosis compared with intrapool crosses in both mega-environments. Generation means analysis revealed the importance of additive gene effects and dominance × dominance epistasis in Mediterranean and German environments. Dominance effects and additive × additive epistasis for yield were negligible in most crossing groups. Since intrapool crosses of Mediterranean germplasm in Mediterranean environments and crosses of Minor and Major germplasm in the German environments were most promising, we suggest crosses among adapted germplasm for hybrid breeding and for establishing new base material in line breeding in faba bean.     

氮钾配施对油菜产量及氮素利用的影响

实际生产中氮钾肥投入不平衡严重限制了氮肥肥效及作物的产量潜力。为了探明不同施氮量下钾肥施用对油菜产量及氮素利用的影响,于2016—2017年及2017—2018年在湖北省武穴市开展连续2年的田间试验,采用氮钾两因素完全试验设计,设氮0、90、180、270 kg N hm-2和钾0、60、120、180 kg K2O hm-2各4个水平。在油菜成熟期取样测定产量、地上部氮钾积累量以及氮肥利用率。结果表明,在钾供应不足时(K0和K60),冬油菜施用氮肥的平均增产率为113.7%,而在钾供应充足的条件下(K120和K180),施用氮肥的平均增产率高达172.9%;与K0处理相比, K120处理冬油菜氮肥回收利用率平均提高了16.6%,继续增施钾肥对不同施氮量下冬油菜氮肥回收利用率的进一步提高无显著影响;达到区域平均产量时,钾供应充足较低钾(K60)投入平均降低33.9%的氮肥用量。综上所述,氮钾配施显著提高了冬油菜产量和氮肥利用率,在冬油菜实际生产中除了重视氮肥施用外,应增加钾肥投入,通过优化氮钾肥配施比例可进一步提高油菜产量,实现冬油菜高产和养分高效。     

Effect of density,cultivar and irrigation on spring sown monocrops and intercrops of wheat (Triticum aestivum L.) and faba beans (Vicia faba L.)

Spring-sown intercrops of wheat (Triticum aestivum L.) and faba beans (Vicia faba L.) were grown in three experiments at the University of Reading, UK. One wheat cultivar, Axona, and one (experiment 1) or two bean cultivars (experiments 2 and 3) Scirocco and Maris Bead, were grown as sole crops and intercrops at 50%, 75% and 100% recommended density. Experiments were rainfed but irrigation was an additional treatment in experiment 3. Biomass and seed yields of both wheat and faba beans were greater when monocropped than when intercropped. There was no evidence that radiation use efficiency (RUE) of intercrops was significantly different from sole crops. In all intercrops there was no significant effect of density on biomass, RUE or seed yield, though there were compensating changes in yield components. Seed yields of Maris Bead were significantly greater than Scirocco in experiment 3 but not experiment 2. There was no significant effect of irrigation on RUE or on wheat biomass and seed yield, but there was a trend for irrigation to increase faba bean biomass (P = 0.07) and seed yield (P = 0.06). With later sowing in experiments 2 and 3, time to harvest was shorter and wheat and bean biomass, seed yield and RUE were reduced. All land equivalent ratio (LER) values for both biomass (maximum 1.23) and seed yield (maximum 1.44) were greater than 1, with one exception in experiment 3, indicating that intercrops of wheat and faba beans make more effective use of land than equivalent sole crops. Partial LERs for faba beans were always lower than those of wheat. The tendency was for highest LERs to occur at 75% recommended density.     

Genetic analysis of the nitrogen and phosphorus utilization efficiencies in mature spring barley plants

Inheritance of the efficiency of nitrogen and phosphorus utilization in grain production was studied in diallel hybrids of spring barley. Effects of varied NPK fertilization and soil moisture on the genetic variance was evaluated at maturity in pot‐ and field‐grown plants. A preponderance of general combining ability effects was found for the efficiency ratios and utilization efficiencies, suggesting that the generative efficiency indices were mainly controlled by an additive genetic system. However, the relatively high narrow‐sense heritabilities (0.33‐0.81) found under optimal conditions tended to decline to 0.00‐0.36 following water and nutrient shortages. The importance of non‐additive gene effects for utilization efficiencies was demonstrated in the field under reduced nutrition. This leads to the conclusion that the involvement of additive gene action should facilitate selection efforts only under favourable environments. Selection delayed until later hybrid generations should be used when trying to improve the nutrient efficiency of barley under less favourable nutrition conditions.     

Pattern analysis and genotypic x environment interactions in faba bean (Vicia faba L.) populations

Summary Twenty-nine populations of faba bean (Vicia faba L. subsp. major, equina and minor) of mediterranean origin were evaluated for the genetic variability of 12 biomorphological characters at four locations in Apulia and Basîli cata regions (Italy) in 1983–84.A pattern analysis appoach, based on classification and ordination procedures is presented for to characterize differences among population in mean performance and response across environments. Informations about G × E interaction were obtained.Research work supported by CNR, Italy. Special grant I.P.R.A. Sub-project 1. Paper N. 1099.     

Genetics of resistance to 3 isolates of Ascochyta fabae on Faba bean (Vicia faba L.) in controlled conditions

Summary Genetics of resistance to Ascochyta fabae Speg. in Vicia faba L. was studied with a final objective to develop resistant faba bean varieties to Ascochyta blight. The study was conducted separately on 3 single spore isolates (AF10-2 and AF13-2 from Tunisia and AF4-3 from France) and belonging to different groups of virulence (GV1 and GV2). Important general combining ability (GCA) effects were found especially with isolates AF10-2 and AF4-3. Specific combining ability (SCA), although significant for the 3 isolates, was important only with AF13 -2, but less important than GCA. Additive gene effects were predominant to non-additive effects. Lines 29H and A8817 transmitted to their progenies resistance to the 3 isolates, whereas 14–12 and 19TB conferred resistance to their progenies only with isolates AF13-2 and AF4-3, respectively. In the material studied, resistance was generally controlled by dominant genes but also could be attributed to recessive genes although less frequent. Analysis of segregation in the F2 of 2 crosses between the resistant lines (A8817 and 29H) and the susceptible line (14–12) with isolate AF4-3 revealed dominant monogenic control at the level of leaves in the 2 resistant lines and, in addition, a recessive gene controlling resistance of stems. Non-allelic interactions were occasionally manifested and their origin appeared to be due to line 19TB. A recurrent selection scheme was proposed with the objective to develop improved open-pollination populations and synthetic varieties responding to the objective of the national Tunisian research programme on faba bean.     

Inheritance of nitrogen and phosphorus utilization efficiency in spring barley at the vegetative growth stages under high and low nutrition

Inheritance of the nitrogen and phosphorus utilization efficiencies (NUE and PUE, respectively) and that of the tolerance (T) to limited NP nutrition was investigated in spring barley crosses at the vegetative growth stages. Plants were grown in sand-vermiculite cultures under high and low NP nutrition. In a diallel set (Ps and F₂s), both general combining ability (GCA) and specific combining ability (SCA) effects were significant for the variation in NUE and PUE, while the variation in T was mainly associated with GCA effects. The contribution of nonadditive genes for the utilization efficiencies was found to increase under nutrient shortages. Overdominance of genes was detected. The characters exhibited low heritabilities (0.10-0.42). Generation means analysis in two cross-combinations revealed significant effects of epistatic gene interactions. It was assumed that the involvement of both the dominance effects and epistatic interactions would not facilitate selection efforts to improve the characters in spring barley at its vegetative growth. Such selection should be performed among families of later generations. The genotype-nutrition interactions observed suggest that selection under diverse nutrition rates would be necessary for the more precise evaluation of barley efficiency under less favourable soil fertility.     

Changes in protein electrophoretic patterns during germination of broad beans (Vicia faba L.) with and without hard-to-cook characteristics

Summary Changes in seed proteins over a five-day germination period in a single cultivar of broad bean grown at different locations were examined using aluminum lactate polyacrylamide gel electrophoresis (AL-PAGE). Seed proteins were extracted in 0.1 M acetic acid containing 10% 2-mercaptoethanol. Extractability of proteins was less in beans which were hard-to-cook. Unlike soft-to-cook, the beans which developed hardness due to growth location showed differences in their electrophoretic patterns and had additional protein spots as revealed by 2-D AL/SDS-PAGE procedure. Continuous but non-uniform disappearance of some proteins and formation of new proteins was observed during germination of half seed segments. Disappearance of protein bands and loss of staining intensity appeared to be more abrupt in beans without hard-to-cook characteristics as compared to those that were hard-to-cook. Electrophoretic patterns of the developing root-shoot axes from soft and hard seeds were almost similar regardless of initial differences in their cotyledon proteins. Shoot/root axes developing from hard seeds showed better growth compared with those of the soft seeds.     

核桃树体不同器官氮、磷、钾含量及累积分布特征

为了探明核桃树体氮磷钾营养分布推动核桃合理施肥,以10年龄辽核1号为试材,于果实采收期对其进行整株采样肢解,研究了核桃树体生物量的构成特点、氮、磷、钾含量和累积分配特性。结果表明,多年生营养器官是干质量分配的主体,一年生器官占总干重的28.6%,其中主要是叶片和果实;多年生器官占61.5%,根系占9.9%。各器官中氮、磷、钾含量差异显著,氮的含量以种仁中最高,其次是叶片;磷含量以种仁中最高,青皮次之;钾含量以青皮最高,硬壳、种仁次之。氮磷钾吸收累积量表现为：氮＞钾＞磷,比例为13.4:1:4.4;一年生器官养分累积量＞多年生枝干＞根系。每生产100kg干商品核桃果实需提供N 10.3kg、P 1.15kg、K 8.76kg。     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Genetic variation for nitrogen use efficiency in winter wheat (Triticum aestivum L.)

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.     

Identification of QTLs for phosphorus utilization efficiency in maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.) across P levels

It is necessary to develop maize plants that are productive when grown in phosphorus (P) deficient soils because of the high cost of P supplementation in soils. The shoot phosphorus utilization efficiency, the whole phosphorus utilization efficiency of plant and root/shoot ratio as well as the quantitative trait loci associated with these traits were determined for a F_2:3 population derived from the cross of two contrasting maize (Zea mays L.) genotypes, 082 and Ye107. A total of 241 F_2:3 families were evaluated in replicated trials under deficient and normal phosphorus conditions in 2007 at Southwest University. The genetic map constructed by 275 SSR and 146 AFLP markers spanned 1,681.3 cM in length with an average interval of 3.84 cM between adjacent markers. Phosphorus was determined in harvested plants separated into two portions, roots and shoots with leaves. The sum of the two portions was used as an expression for P in the whole plant. By using composite interval mapping, a total of 5–8 distinct QTLs were identified under deficient and normal phosphorus, respectively. SPUE and WPUE under deficient phosphorus were controlled by one QTL, which was in the interval bnlg1518-bnlg1526 (bins 10.04) on chromosome 10. The loci of QTLs were same for SPUE, WPUE and RSR under normal phosphorus, which were in the interval bnlg1518–bnlg1526 (bins 10.04) and P2M8/a-bnlg1839 (bins10.07) on chromosome 10. Unlike regions conferring phosphorus utilization efficiency and root shoot ratio under normal phosphorus, the region under deficient phosphorus showed that genes controlling phosphorus utilization efficiency or root shoot ratio might be different. These results may be useful to breeding programs in marker assisted selections to identify phosphorus tolerant genotypes. Junyi Chen and Li Xu contributed equally to this work.     

普通小麦氮素利用效率相关性状全基因组关联分析

氮元素在粮食作物生长和发育过程起着不可替代的作用。发掘氮素利用效率相关基因对于提升小麦产量、减少环境污染具有重要意义。植株根系构型(rootsystemarchitecture,RSA)代表着根系的结构及空间造型,显著受氮素水平影响。本研究在正常供氮和缺氮两种氮素水平下,对160份来自黄淮冬麦区和北部冬麦区普通小麦品系的根系构型相关性状(总根长、总根表面积、总根体积、平均根直径和根尖数)进行统计,并结合小麦660KSNP(single nucleotidepolymorphism)芯片基因分型数据对根系相关性状的相对值进行全基因组关联分析,以期发掘氮素利用效率相关位点。本研究检测到34个与氮素利用效率显著关联的SNP位点,可解释6.9%～15.4%的表型变异。关联位点在所有染色体均有分布,主要集中于1A、2B、3B、5B、6A、6B和7A染色体。11个位点与已报道位点重叠或接近,其他23个位点可能为新的位点。另外,在3B染色体上发现一个编码E3泛素连接酶的候选基因。     

磷对花生氮素吸收和利用的影响

磷是植物必需营养元素之一,以多种方式影响作物氮吸收、利用。花生属于豆科作物,氮素营养来源包括土壤、肥料和根瘤固氮。本研究以山东省主推品种花育22号(大花生)和花育20号(小花生)为材料,设置5个施磷(P2O5)水平(0、45、90、135和180 kg hm–2),利用15N示踪技术,进行了2年桶栽试验。结果表明,施磷提高了两花生品种肥料氮、土壤氮及根瘤固氮积累量,其中根瘤固氮积累量的增幅大于土壤氮和肥料氮,年份和品种间表现基本一致;随施磷量增加,根瘤数量、鲜重及根瘤固氮积累比例呈增加趋势,土壤氮、肥料氮积累比例呈降低趋势;施磷量在45～90 kg hm–2范围内,氮肥利用效率、荚果氮素利用效率及产量均呈增加趋势,施磷量超过90 kg hm–2,上述三指标呈降低趋势或不再增加;磷肥农学效率随施磷量增加而降低;根瘤固氮积累量与荚果产量、植株全氮积累量呈极显著正相关,与土壤氮、肥料氮积累比例及氮素荚果利用效率呈极显著负相关。根瘤固氮积累比例与土壤氮和肥料氮积累量、供氮比例及氮肥利用率呈极显著负相关。综上,施磷能增加花生根瘤固氮供氮量及供氮比例,降低对肥料氮和土壤氮的依赖,但过量施磷不利于氮、磷效率和产量的提高。45～90 kg hm–2 (P2O5)为花生适宜施磷量。