The Effect of Component Frequency and Plant Density on Yields of Cultivar Mixtures in Spring Faba Beans

The effect of plant density and component frequency was examined in mixtures of two spring faba bean ( Vicia faba L.) cultivars Donas and Minden grown in a replacement series experiment in the field. There were two densities, 44 and 25 plants m⁻².
At low density mixtures yielded significantly more (+ 22.5 %) than the mean of the components grown in monoculture. The advantage was considerably reduced (+ 7.8 %) at high density. A frequency dependent advantage was observed when the proportion of the components in mixtures was varied. At high density and when averaged over the two densities, the greatest yield advantages were obtained when Danas , the high yielding component represented 75 % of the mixture, whilst at low density the greatest advantage was achieved at 50 : 50 mixture. Such gains were either due to component co-operation or complementation type interactions.
Mixtures produced greater total dry weights and more podded nodes per plant than the mean of the components. The remaining characters had values which were more or less similar for monocultures and mixtures.     

Nitrogen and Phosphorus Effects on Faba Bean Yield and Some Yield Components

The faba bean is among the major grain legumes cultivated in Ethiopia and is used extensively as a break crop in the highlands. Although a blanket application of DAP (diammonium phosphate) at the rate of 100 kg · ha^?1 has been practised in faba bean production in the country, this was not based on research results. In addition, little information is available on the response of the crop to N and P fertilizers under diverse environmental conditions. Hence, field experiments were carried out at three locations in 1991, seven locations during 1992 and 1993 and at one location in both 1993 and 1995 to determine faba bean response to N and P fertilization. Five levels of N (0, 9, 18, 27 and 36 kg N · ha^?1 as urea) in factorial combinations with four levels of P (0, 23, 46 and 69 kg P₂O₅ · ha^?1 as TSP [triple super phosphate]) were studied in a randomized complete block design with four replications in the first year. In the remaining years four levels of N (0, 18, 27 and 36 kg N · ha^?1 as urea) in factorial combinations with four levels of P (0, 23, 46 and 92 kg P₂O₅ · ha^?1 as TSP) were used in a randomized complete block design with three and four replications at one and seven locations, respectively. Results indicated that a positive linear response of faba bean seed yield was noted at all locations (except Debre Zeit and Burkitu) to P fertilization, while a significant quadratic response was also found at Holetta. In addition, plant height, above ground biomass and number of pods per plant were positively influenced by P application while the effect of N on these was mostly nonsignificant. Faba bean seed yield response to N was noted at only two out of eight locations; in most cases, nonsignificant and inconsistent seed yield responses to N fertilization were obtained. There was nonsignificant N × P rate interaction. In conclusion, we do not recommend supplemental N application to faba bean at six out of eight locations but we recommend the application of P fertilizer to faba bean at almost all locations (with the exception of Debre Zeit) and for other soils deficient in available P. Further work is recommended on the determination of critical levels for soil-available P, below which P fertilization should be practised for optimum faba bean seed yield.     

蚕豆异交率相关因素研究及应用进展

蚕豆是常异花授粉作物,异交率一般为20%~30%,最高可达84%。媒介昆虫、气候条件、地理因素、种植密度、品种基因型、花序的小花数量及小花结构特点、田间环境等都对异交率产生影响,媒介昆虫是异交发生的主要途径。异交会导致种质一致性的丧失,给资源的保存利用、品种繁育和应用基础研究等带来一定阻碍,但同时异交又是群体遗传多样性保障和杂种优势利用的重要条件。本文从异交率、异交媒介、异交影响因素及异交率的应用研究4个方面总结蚕豆异交率研究和应用情况,并对今后研究方向进行展望。     

Yield Stability in Faba Bean,Vicia faba L. 1. Variation Among Inbred Lines*

Cultivation of faba beans (Vicia faba L.) is hampered by poor yield stability. The genetic variation at the homozygous level for yield stability in the gene pool of the small-seeded and indeterminate European faba beans and the usefulness of auxiliary traits for the improvement of yield stability were investigated. The concept of stability, based on the regression technique, was applied. A sample of 36 faba bean lines was tested in 16 environments and a subsample of eight lines was tested in 11 additional environments. Significant differences were found between lines for yield stability parameters, but the repeatability of the results was limited. Early maturity correlated markedly (r = 0.51^**) with one of the yield stability parameters (deviation from regression). Although lodging resistance was not correlated with the stability parameters, it proved to be a safety factor for performance.     

施肥对蚕豆根瘤及产量的影响

针对冀北蚕豆主产区,研究了不同施肥处理对蚕豆根瘤及产量的影响。研究表明,磷钾肥可以促进根瘤的形成;在盛花期,根瘤的数量和干重随着施氮水平的增加呈先增加后减少的趋势,且N60施氮水平时根瘤的数量（56.0个/株）和干重（0.121g/株）值最高,分别比对照增加了46.6%和49.4%;在成熟期,根瘤数量和干重均随着氮肥的增加整体呈降低趋势,氮肥抑制根瘤的形成。施用磷钾肥和氮磷钾肥处理干物质积累量均高于对照处理。适量的氮肥与磷钾肥配施可促进蚕豆根、茎、叶、子粒的生长,过多的氮肥则会抑制植株     

Selection in Faba Bean for Tolerance to Broomrape, Orobanche crenata Forsk.

Six populations of faba bean (Vicia faba L.) were developed through various selection schemes to examine the influence of selection In improving tolerance to Orobanche crenata (Forsk.) in local faba bean stocks. All populations trace their origin to 209 farmers’ seed lots that were collected from Egypt. The entries of each population were grown during the 1982/1983 season in the Orobanche nursery located at Giza in Egypt. Comparison among means of the selected, populations showed that more progress in improving Orobanche tolerance could be achieved from combined selection between and within lots. Between-lots selection was less efficient than single-plant selection. Results, of this study show that considerable progress could be achieved from selection for Orobanche tolerance in local faba bean germplasm. There was sufficient residual genetic variation in the selected populations to expect substantial progress from further selection for most tolerance traits.     

The Relationship Between Sugar-Nitrogen Ratio and Reproductive Organs Abscission in Faba Bean (Vicia Faba L.)

The changes of soluble sugar and total nitrogen content of vegetative organs in faba bean, sugar-nitrogen ratio, abscission of reproductive organs and the relationship between sugar-nitrogen ratio and abscission probability were studied using the faba bean cultivar Xichang Dabai . Plants were field grown in 1986, 1988 and 1990. The lands were separated into high yield land, middling yield land and low yield land according to grain yield at maturing stage. The soluble sugar content in vegetative organs (leaf + stem) was greatest from branching to floral initiation stages and pod-set to filling grain stages, and distinctly decreased at the onset of bloom and maturing stages. The total N content was greatest at branching stage, and gradually decreased with growth. In general, the sugar and total N contents in high yield lands were greatest, followed by that in middling yield and low yield lands. The sugar-nitrogen ratio varied depending on the soluble sugar content.
Average yield on high yield lands, middling yield land and low yield land across 3 years were 5048.77 kg/ha, 3744.01 kg/ha and 2378.22 kg/ha, respectively. The total reproductive organs abscission exceeded 90 % of total flower buds. Abscission probability averaged across 3 yield lands and 3 years were 21.6 %, 84.0 % and 32.8 % in flower buds, flowers, and pods, respectively. Node 7–12 of canopy produced more flowers, and fewer flowers and pods were produced in the upper and lower regions. Photosynthate supply has been implicated in control of abscission. Faba bean reproductive organs abscission probability increased with the sugar-nitrogen ratio of vegetative organs decreasing. It seemed that the soluble sugar content influenced significantly the shedding rate during flowering and pod-growing stages.     

Effects of Faba Bean Leaves in Different Positions on the Yield and Photosynthetic Compensation after Defoliation

In a field experiment in the winter seasons of 1985/86 and 1988/89 at Xichang, China, the effects of defoliation on seed yield of Vicia faba and its photosynthetic compensation were investigated by removing all leaves, some leaves from different plant positions at the beginning of flowering and the beginning of pod formation. Seed yield decreased by 37.3–52.3 % in plants with upper leaves removed at the beginning of flowering. Removal of middle leaves at the beginning of pod formation had the most significant effect, followed by the of upper and lower leaves removed, causing yield decreases of 43.4–64.3 %, 18.6–24.7 % and 8.9–12.3 %, respectively. Removal of leaves at the beginning of pod formation resulted in a greater reduction in seed yield, total dry weight, harvest index, and number of pods and seeds per plant than leaf removal at the beginning of flowering.
The photosynthetic rate and export rate of photosynthate of upper leaves at the beginning of flowering, and middle leaves at the beginning of pod formation were the greatest during both years of the experiment. Photosynthetic rate increased and reached its maximum at 4–5 days after leaf removal, then decreased, but, yet greater than the control leaves at 9–11 days after leaf removal. In the meantime, transport of photosynthetic products was accelerated. In general, removal of leaves from the upper and middle third of the plant increased the export rate of photosynthate by ca. 20 %. Photosynthetic compensation could not fully make up the loss caused by leaf removal, so grain yield was decreased by all treatments. The full defoliation decreased yield by > 70 %.     

氮肥和种植密度对蚕豆结瘤和生长的影响

在胶泥土和沙壤土两种土壤条件下,研究了5种氮肥用量和3种种植密度对蚕豆结瘤和生长的影响。结果表明:蚕豆在不同土壤条件下结瘤能力差异较大,在氮肥施用量低于240kg/hm²的情况下,适当提高氮肥施用量有助于提高蚕豆的结瘤能力。蚕豆的行距从25cm增加到50cm,降低了种植在胶泥土上蚕豆的结瘤能力,却提高了种植在沙壤土上蚕豆的结瘤能力。同样,适量提高氮肥的施用量,蚕豆的生物量、有效荚数、子粒产量和株高均得到提高。增加蚕豆的行距,促进蚕豆的生物量、有效荚数、子粒产量,降低了蚕豆的株高。     

Factors Affecting the Differentiation of Resistant Faba Bean Plants after Inoculation with Sclerotinia trifoliorum

Faba bean (Vicia faba L.) plants 3, 4, 5 and 6 weeks old were inoculated at different internodes by carrot root pieces colonized by the fungus Sclerotinia trifoliorum Eriks. The plants were left in the growth chamber for 72 h. In addition, eight faba bean cultivars, 4 weeks old, were inoculated by the same inoculum which was left on the stems for various lengths of time. When the inoculum was removed, the plants were scored for disease severity. The highest disease seventy was on the youngest tissues inoculated. Susceptible and partially-resistant cul-tivars could be differentiated effectively when the inoculum was removed 48 to 72 hours after the inoculation.     

Differential Drought Responses of Faba Bean (Vicia faba L.) Inbred Lines

Drought responses of 19 inbred faba bean lines of different origin were studied in the field under rain shelters with and without irrigation. Inbred lines differed significantly in response to drought (P < 0.01): those with a lower drought sensitivity index (SI) (more resistant) originated from the drought-prone regions characterized by smaller plant size (r = 0.93), and more pods and seeds per plant (r ≥ 0.90) regardless of seed size, while lines with higher SI (more sensitive) were those which mainly exhibited higher yield under favourable conditions accompanied by a greater biomass. In a greenhouse experiment under mild drought (−0.15 MPa soil water potential), comparisons between relatively drought-sensitive (Adriewaalse) and drought-resistant (L7) inbred lines showed that Adriewaalse used 38 % more water than L7 and also produced 40 % more biomass. There was a stress-induced decrease in osmotic potential (ψ_s) in both lines (by 0.72 and 0.50 MPa for Adriewaalse and L7, respectively) accompanied by decreased turgor in Adriewaalse and increased turgor in L7. The difference in drought-induced solute accumulation between lines was diminished when solute accumulation due to water loss and growth inhibition was considered, which indicates that solute accumulation was the result of a concentration effect. Similarly, lower SI in the field was not the result of osmotic adjustment, as the relationship between SI and drought-induced decrease in ψ_s was negative. The water use efficiency of both inbred lines increased markedly with increasing water deficit, though there was no difference between the lines. It was concluded that differences in drought resistance between these inbred faba bean lines were manifested through plant size-induced water demand (avoidance) but were not associated with osmotic adjustment (tolerance).     

Genetic Structure of Three Open-Pollinated Faba Bean Varieties (Vicia faba L.)*

To study the genetic structure of open-pollinated faba bean varieties, three sets of genotypes were generated from each of the varieties ‘Minica’, ‘Kristall’, and ‘Deiniol’: (1) inbred lines developed by single-seed descent in bee-proof isolation cages, (2) intravanetal and (3) intervarietal F₁-hybrids produced by controlled hand crossing. In 1989 and 1990, a total of 144 entries, including the three open-pollinated source varieties, were grown in single-row plots with two replications at two locations in Western Germany. Performance data of the inbred lines revealed relatively large genotypic variability within each variety, for all the characters studied, which was greater in ‘Deiniol’ and ‘Kristall’ than in ‘Minica’. An average yield heterosis of 20 %, 39 % and 57 %, respectively, was found for the intravarietal hybrids, whereas that of the intervarietal hybrids varied between 70 and 73 %. Compared to the mean yield of the inbred lines the superiority of the open-pollinated source variety was small and not significant in ‘Minica’ (6 %), but it was large and highly significant in ‘Kristall’ (22 %) and ‘Deiniol’ (37 %). The present investigation revealed in faba bean that similar performance levels of open-pollinated varieties may result from either high per se performance under inbreeding with low heterosis values or from lower per se performance but with high heterosis values.     

Autofertility and Bee Visitation in Winter and Spring Genotypes of Faba Beans (Vicia faba L.)

Differences in the expression of autofertility and in the evidence of attractiveness to bees were investigated in both autumn-sown and spring-sown faba beans. All six winter stocks and one spring stock expressed very little autofertility, with averages of only 10% of flowers and 7% of ovules fertilized when undisturbed. Three other spring stocks, including a closed-flower population, were moderately autofertile, with 22% of flowers and 17% of ovules fertilized when undisturbed. The remaining two spring stocks, both English cultivars, expressed good autofertility, with 50% of undisturbed flowers and 44% of ovules fertilized. Current levels of autofertility in the winter and closed-flower stocks were inadequate to allow the development of a desirable distribution of pods without substantial bee visitation. If levels of autofertility could be raised simply by selection within populations, then they should have been much higher in these stocks. Therefore, autofertile parents will probably have to be included in programmes for breeding cultivars with improved levels of auto fertility. The closed-flower population received significantly less bee visitation than the other stocks in the spring trial. No variation in attractiveness to bees was found among the open-flowered spring stocks, nor among the winter stocks.     

中国蚕豆种质资源ISSR标记遗传多样性分析

利用ISSR标记对中国18个省(区)的527份春播区和秋播区蚕豆资源的遗传多样性与亲缘关系进行分析。结果表明,11个ISSR引物共扩增出278条清晰的条带,其中多态性条带268条(占96%)。不同地理来源蚕豆资源群间的基因多样性指数在0.1267~0.2509之间,平均为0.1716;Shannon指数范围为0.1932~0.3767,平均为0.2608。两指数均以内蒙古资源群最高,云南和甘肃资源群次之,江西资源群体最低。非加权配对算术平均法(UPGMA)的聚类分析和二维主成分分析(PCA)结果表明,中国春播区和秋播区蚕豆资源明显不同,浙江和四川的资源形成独立的组群,明显不同于其他省份,其遗传背景独特,有待进一步研究。中国蚕豆种质资源遗传多样性差异和遗传关系与其生长习性、生态分布及地理来源密切相关。     

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.     

不同密肥条件对蚕豆农艺性状和产量的影响

为了明确优良品种的高产栽培技术,实现良种良法配套应用推广,更好地发挥优良品种的增产潜力,以‘成胡14’为材料,研究密度、肥料水平对蚕豆农艺性状和产量的影响。结果表明,密度和肥料对大部分农艺性状和产量均表现极显著影响,且农艺性状的密度效应大于肥料效应,产量的肥料效应大于密度效应。在5个密度梯度和4个肥料梯度中,以15.0万株/hm2和375 kg/hm2时‘成胡14’的各农艺性状和产量均表现较好。主成分分析结果表明,第一和第四主成分偏重不利于产量的提高,第三主成分对产量影响较小。在合理的栽培技术调控下,‘成胡14’可实现突出相应农艺性状和高产的协调。     

Development and Yield Formation of Autumn- and Spring-sown Faba Beans in Northern Germany as Affected by Seasons, Sowing Dates and Varieties

Field trials were conducted with autumn- and spring-sown faba beans in Northern Germany during four seasons to examine the expected preceding development of autumn-sown plants, its possible transformation into a higher yield potential and its dependence on sowing dates and varieties. Height, appearance of leaves, inflorescences, mature flowers, potential and actual pot set was rated weekly, and flower initiation and tillering occasionally. Comparison was made for one winter type sown in autumn and spring, and between 6 winter types and 3 spring types, in two seasons each.
Development of autumn-sown plants significantly preceded that of spring-sown in each year, regardless of the plant material used. The mean advance, diminished considerably with time due to prolonged developmental phases in autumn-sown plants which, however, did not improve vegetative, generative or reproductive potentials of main tillers. Potentials formed by the six winter types, interacted strongly with the seasons, at least in part due to changing plant densities. Thus, only a very few traits appeared typical: a short stature with few leaves for Avrissot and the opposite for Bourdon , a high number of ripening pods for Avrissot and a low number for Banner . Early compared to late sowing in autumn increased the number of leaves, and in one year even the number of mature flowers and ripening pods per tiller, but values of early sowing never exceeded those of spring sowing. Enhancement of tiller formation by early compared to late sowing diminished after spring; nevertheless about two reproductive tillers per plant in autumn-sown stands always led to a higher density of tillers than in spring-sown.     

Variation in Reaction of Faba Bean Lines to Different Accessions of Orobanche crenata Forsk.

Three pot experiments were earned our to investigate the variation among geographic accessions of Orobanche crenata Forsk. in their ability to attack different stocks of Vicia faba L. Orobanche accessions were quite different in their influence on the performance of genetic lines of the host. However, host parasite relationships appeared to be dependent upon environmental conditions. The usefulness or host genotypes for differentiating between parasite accessions was rather limited. The number of Orobanche shoots per host plant does not appear 10 be a precise indicator of host tolerance although it has been frequently used for this purpose.     

Yield Structure of Winter Faba Beans Grown in Northern Germany in Dependence of Different Environments, Seed Rates, Sowing Rates and Genotypes

Two series of field trials were performed at three sites in Schleswig-Holstein between 1981 and 1988 to inquire into the yield structure of European winter types of Vicia faba L. and to compare their yield potential with that of spring types. Due to low winter survival, 6 winter types could be evaluated only in 4 environments in dependence of 1–3 sowing times (series α: seed rate 30/m²) and 1 winter type in 5 environments in dependence of 3 sowing times and 3 seed rates (series β: seed rate 15, 30, 45/m²). Seed yield of winter type averaged 410 g/m² (D.M.) surpassing spring types by about 14 %. Environments caused a considerable variation in yield (275–620 g/m²) and in each yield component of winter types, while sowing dates and seed rates hardly affected the components seeds/pod and seed weight, which displayed stable genotypic rank orders. Compensative forces among the components plants/m², tillers/plant and pods/tiller, were established. Plant densities of less than 10/m² in spring, generally led to seed yield below 350 g/m². Variation between 15–30 plants/m² due to environments, sowing times or seed rates were frequently not fully compensated by tillering of plants, but often variation of the thus formed yield potential was reduced by pod set of tillers resulting in 210–270 pods/m². The direction of correlations of pods/tillers with tillers/plant and plants/m² differed due to experimental conditions whereas negative correlations between pods/tiller and tillers/ m² were generally evident. Tillering was significantly influenced by the sowing time, though the increase because of early sowing was often covered by compensative effects of different plant densities. A genotypic capability to produce reproductive tillers was demonstrated using an approach which considered different plant densities and compensative forces. Neither a genotypic capability of tillers to set pods nor direct effects of environments or sowing time on pod set were established.     

Susceptibility of Faba Bean (Vicia faba L.) to Heat Stress During Floral Development and Anthesis

Experiments were conducted over 2 years to quantify the response of faba bean (Vicia faba L.) to heat stress. Potted winter faba bean plants (cv. Wizard) were exposed to temperature treatments (18/10; 22/14; 26/18; 30/22; 34/26 °C day/night) for 5 days during floral development and anthesis. Developmental stages of all flowers were scored prior to stress, plants were grown in exclusion from insect pollinators to prevent pollen movement between flowers, and yield was harvested at an individual pod scale, enabling effects of heat stress to be investigated at a high resolution. Susceptibility to stress differed between floral stages; flowers were most affected during initial green‐bud stages. Yield and pollen germination of flowers present before stress showed threshold relationships to stress, with lethal temperatures (t₅₀) ?28 °C and ~32 °C, while whole plant yield showed a linear negative relationship to stress with high plasticity in yield allocation, such that yield lost at lower nodes was partially compensated at higher nodal positions. Faba bean has many beneficial attributes for sustainable modern cropping systems but these results suggest that yield will be limited by projected climate change, necessitating the development of heat tolerant cultivars, or improved resilience by other mechanisms such as earlier flowering times.