Yields and chemical composition of whole-crop field beans and their components during pod-filling

Experimental trials in both rainfed and irrigated conditions were carried out in Central Spain with the aim of assessing the best time to harvest whole-crop winter field beans for forage. Three times of harvesting during the pod-filling phase were considered: seed with less than 20% DM (L,), 30-35% (L:) and over 85% (Lj). At the early pod-setting stage (Lj), the stems and leaves represented 75% of the total aerial biomass. At pod maturity (L3), this percentage was reduced to 27%. Over the same period, Lj to L3, the seed's contribution rose from 8% to 59%. Chemical composition of the different plant components varied markedly during the pod-filling phase. Lignin in leaves and pod-shells rose abruptly from 082 and 090% DM at L, to 7-82 and 7-01 % DM in L3. Crude protein of the seed varied only slightly between harvests. Mean DM yields over both years of 3 44 ± 0-46. 607 + 071 and 428 ± 037 tDM ha' were obtained for the whole plants in rainfed conditions at the L₁, L₂ and L3 stages respectively. Corresponding values for irrigated conditions were 552 +0-7I, 8-66± M 6 and 684±082 tDM ha"'. Taking into account the chemical composition of the whole plant at the three times of harvesting (mean values in both conditions of 675, 657 and 641 g I00gDM-'for DDM and 215, 18 7 and 186% DM for CP), it is concluded that the highest estimated energy and protein yields would be obtained by harvesting the plant at the Li stage (seeds with 30-35% DM).     

Effect of harvest time on yield and pre-harvest quality of semi-leafless grain peas (Pisum sativum L.) as whole-crop forage

The aim of the work was to study changes in the yield and nutritional characteristics of whole crop semi-leafless field pea over two growing seasons in the Po plain, Italy. Samples of two cultivars (Baccara and Sidney) were collected from flowering to grain maturity. The developmental stage, yield, dry matter (DM) content, crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), starch, water soluble carbohydrates (WSC), gross energy (GE), organic matter digestibility (OMD) and the net energy for lactation (NE_L) were determined at each harvest. The forage characteristics were regressed on the growing degree days (GDD) with 4.4 °C as the base temperature. The DM yield increased with advancing maturity from 0.5 to 8.91 Mg ha⁻¹, while the CP decreased from 261 to 159 g kg⁻¹ DM. During the whole growth cycle the GE, OMD, NE_L and milk forage units (milk FU) were almost steady. No differences were observed between the cultivars for any of the measured parameters. At grain maturity, the crop produced over 4.0 Mg ha⁻¹ DM of grain. The CP, starch and WSC of the grain did not show any differences between the cultivars or years. The data showed that the nutritive quality of the forage of the semi-leafless grain pea harvested as a whole crop for ensiling purposes did not diminish with maturity and could help improve the self-sufficiency of dairy farms, in terms of home-grown protein forages.     

Inheritance of resistance to sclerotinia stem rot (Sclerotinia trifoliorum) in faba beans (Vicia faba L.)

Stem rot, a fungal disease caused by Sclerotinia trifoliorum Eriks., is often a serious problem in many important forage legumes including faba beans (Vicia faba L.). Understanding the inheritance of resistance to the disease is essential for effective breeding of resistant cultivars. Experiments were conducted to study the inheritance of resistance to stem rot of faba beans. The F₁, F₂, and the backcross generations of five crosses between four resistant and four susceptible populations (Alto × Polycarpe, A-90 × Polycarpe, ILB-1814 × A-247, A-90 × A-244, VT × Tanagra) were used. The eight populations were crossed properly in the field, and progenies of F₁ and F₂, as well as backcross progenies of F₁ with each of their parents, were evaluated for resistance to stem rot disease under controlled conditions after artificial inoculation of the plants with carrot root pieces colonized by the fungus. On the assumption that inheritance of stem rot resistance is governed by a single dominant gene, no significant differences were found between the observed and the expected frequencies of resistance for progenies, except for one cross. As the expression of resistance to the disease fits the expected ratios for a single dominant gene model, it is concluded that the inheritance of resistance to sclerotinia stem rot in the evaluated faba bean populations is controlled by a single dominant gene.     

Effect of cooking on protein solubility profiles of faba beans (Vicia faba L.) grown using different nutritional regimes

A field experiment was carried out to study the effect ofcooking on protein solubility profiles of mycorrhizal inoculated, phosphorusand sulphur fertilized faba beans under two water regimes. The resultsindicated that cooking significantly (p 0.05) increasedthe G₃-glutelin fraction as well as the insoluble protein butsignificantly (p 0.05) decreased the globulin and albuminfractions; prolamin, G₁-glutelin and G₂-glutelin fractionswere slightly increased. Mycorrhizal inoculation and mycorrhiza +phosphorus + sulphur fertilization significantly (p 0.05) increased albumin content. All fertilizer treatments significantly (p 0.05) decreased the insoluble protein.     

Intercropped wheat (Triticum aestivum L.) and bean (Vicia faba L.) as a whole-crop forage: effect of harvest time on forage yield and quality

Abstract Sole crops and intercrops of wheat (Triticum aestivum L.) and bean (Vicia faba L.), at three harvest dates, representing successive growth stages, were evaluated for biomass production of whole‐crop forage and quality characteristics of crude protein (CP), neutral‐detergent fibre (NDF), acid‐detergent fibre (ADF), water‐soluble carbohydrate (WSC) concentrations and ash content. These tests were carried out for two field experiments, respectively, drilled during the spring of 1997 and autumn of 1997 on Imperial College Farm, Wye, UK. Results indicated that optimum forage yield and quality were obtained from the second to third harvest dates for the spring‐drilled experiment and the second harvest for the autumn‐drilled experiment. Wheat and bean intercrops were higher in total forage dry matter (DM) yield than either wheat or bean grown as sole crops. Field bean intercropped with wheat led to increased forage quality (CP and NDF concentrations) compared with sole wheat, and higher WSC concentrations compared with sole bean. Intercrops also enhanced weed suppression compared with sole bean. It is suggested that winter wheat–bean intercrops may have considerable potential as a moderate‐yielding, relatively high‐quality, low‐input and environmentally benign forage crop with considerable potential with regard to yield and quality and warrant further study.     

In vitro enzymatic hydrolysis of protein and protein pattern change of soya and faba beans during germination

In addition to technological processes like heat treatment, germination can be an alternative process for the improvement of protein quality of legumes. This was demonstrated by enzymatic protein hydrolysis of flour of germinated faba and soya beans, using a pepsinpancreatin enzyme system. SDS-PAGE was used to study the changes in protein pattern of these legumes during germination. In addition, the effect of germination on the content of condensed tannins in flour from germinated faba beans and trypsin inhibitors in flour from germinated soya beans were studied. Germination for five days resulted in a maximum increase in enzymatic protein hydrolysis by 21.3% in flour from faba beans and by 25.7% in flour from soya beans after 12 hours of germination. Protein patterns, obtained with SDS-PAGE demonstrated a considerable protein breakdown during germination between day 2 and 3 in faba beans and between day 1 and 2 in soya beans. The tannin content in flour from faba beans decreased by 29.7% after seven days of germination, but the tannin content of the hulls of the faba beans did not change during that period of germination. The trypsin inhibitors in flour from soya beans decreased by 25.5% after seven days of germination. We conclude that the increased enzymatic hydrolysis of protein in both legumes cannot be explained by a decrease of tannins or trypsin inhibitors. The possible explanation is that through degradation of proteins during germination of the legumes, the cleaved protein fragments are more susceptable for hydrolysis by pepsin-pancreatin.     

Favism-inducing toxins in broad beans (Vicia faba) examination of bean extracts for pyrimidine glucosides

Methods for the isolation and identification of the pyrimidine glucoside, vicine, in extracts of broad beans, are described, By thin-layer chromatography, five fluorescing or fluorescencequenching components of the extracts are identifiable. One of them, which has been isolated from the mixture, is identified as vicine, 2:4-diamino-5:6-dihydroxypyrimidine-5-(-D-glucopyranoside).     

The complete elimination of vicine and convicine from the faba beans by combinations of genetic selection and processing techniques

Out of sixty six faba bean (Vicia faba) cultivars and genotypes grown locally in Egypt and in Syria, the genotype 123 A/45/76 proved to be lowest in its vicine and convicine contents. Furthermore, soaking of this bean variety in 1% acetic acid at 40°C for 48 h resulted in reducing the total vicine and convicine contents of the beans by 90%. Home-made faba beans processing including soaking prior to cooking as in the case of bean cakes resulted in considerable reduction of the vicine and convicine contents by 56 and 34% respectively.     

Validation of the Rostock fermentation test as an in vitro method to estimate ensilability of forages using glass jar model silages as a basis for comparison

This study compared the predictive power of an in vitro fermentation test [Rostock fermentation test (RFT)] with common glass jar silages (GLASS) using maize, fresh and wilted perennial ryegrass and fresh and wilted lucerne. Treatments were made in quadruplicate and included a control variant without additives, sucrose (20 g kg^?1), a homolactic inoculant (Lactobacillus plantarum, 3 × 10⁵ cfu g^?1), a heterolactic inoculant (Lactobacillus buchneri, 1 × 10⁵ cfu g^?1) and combinations of each inoculant with sucrose. The pH was measured in GLASS at days 1·5, 3, 10 and 90, and in RFT at 14, 18, 22, 26, 38 and 46 h, whereas fermentation products were determined at days 3 and 90 in GLASS, and at 46 h in RFT. Linear regressions revealed the closest relation for pH between 10‐d silages of GLASS and 38‐h measurement of RFT (adjusted R² = 0·808) and coefficients of determination for fermentation products were always higher when 3‐d instead of 90‐d silages were compared with 46‐h measurement of RFT. A pH increase in GLASS as indicator of insufficient anaerobic stability was not reproduced by RFT, suggesting that the in vitro test reflects the initial phase of fermentation, which was also indicated by the absence of 1,2‐propanediol in RFT.     

Favism-inducing toxins in broad beans (Vicia faba): Estimation of the vicine contents of broad bean and other legume samples

A method for the estimation of vicine in leguminous seeds and related material has been developed. It involves the extraction and isolation of mixed pyrimidine bases, thin layer chromatography and spectrophotometry. Results obtained withVicia faba (broad bean) samples from various sources are recorded and reference made to data obtained from some other leguminous crops.     

Protein quality of peas as influenced by location,nitrogen application and seed inoculation

A study was conducted to evaluate the contribution of location, N application andRhizobium seed inoculation to variations in seed protein content and amino acid (AA) composition of field peas. The magnitude of AA variations with protein level and the nature of the relationships that are involved were determined. Regression equations to predict AAs from protein were developed for the cultivar Bohatyr. The experiments were carried out at two locations in southern Manitoba in 1994. The levels of N fertilization investigated were: 56, 75, 100, 125, 150, 200, 250 and 300 kg/ha. At each level of N application, seeds planted were eitherRhizobium inoculated or not inoculated. The combination of location, fertilizer treatments and inoculation yielded 192 samples for chemical analyses. The samples were analyzed for dry matter (DM), N and AA contents. Location and N fertilization had significant (p0.001) effects on seed protein content and AA composition. Seed protein content increased with increasing levels of N application. The response of protein to fertilization was not the same in both locations as evidenced from the presence of interaction (p0.01) between location and N application. Except for methionine and cystine, percent AAs in DM increased with increasing levels of N application. The effects of N application on the concentrations of methionine and cystine were not consistent. On protein basis, the concentrations of AAs decreased with increasing levels of N application. The only exception was arginine which strongly increased in concentration. There was no effect (p0.05) of seed inoculation observed in this study. Strong positive correlations (r>0.80) between seed protein content and AA concentrations expressed as percent of DM were found for all AAs except for methionine (r=0.76) and cystine (r=0.51). When AA concentrations are expressed as g per 16 g N, 15 of the 17 AAs were negatively correlated to seed protein content. Only arginine (r=0.78) and aspartic acid (r=0.17) had positive correlations. The regression equations developed from this study could be used to predict the concentrations of AAs except methionine and cystine for the cultivar Bohatyr once the protein content is known.     

A standard grading of fresh cacao beans

Summary The problem of grading of fresh cacao beans for breeding and for taxonomic purpose is discussed. Seven grades are based on the color of transversal cutting of the cotyledons in fully mature beans, and the colors (plate) refer to color standards, namely:Grade 7 attributed to the true Criollos (two types and hybrid) as well as to Porcelain (with a short discussion on this cacao);Grade 6 to the Commerical Criollos (Almost-Criollos);Grade 5 to the Superior Forastero, chiefly Venezuelan Forastero;Grade 4 to the Average Forastero, typified with the Trinitarian Forastero;Grade 3 to the Low grade Forastero, probably corresponding to the Orinocan Forastero;Grade 2 attributed to the Almost Calabacillo (in part corresponding to the Amazonian Forastero);Grade 1 for true Calabacillo. Several examples of cacao grading for regions of Venezuela (and elsewere) and for the kind of cacao are selected, with an example of the yearly fluctuation of the grade in the same tree or cacao. The pod grade value (P.G.V.) as weighted average, is discussed.With one plate     

Bovine faeces as a source of micro-organisms for the in vitro digestibility assay of forages

The aim of this study was to investigate whether bovine faeces could replace rumen liquor collected from fistulated sheep in the determination of organic matter digestibility (OMD) of forages in vitro . The first experiment compared two inocula that had been prepared by mixing 83 and 333 g of cattle faeces with 1 litre of artificial saliva according to the first stage of the in vitro technique of Tilley and Terry ( Journal of the British Grassland Society, 18, 104–111, 1963). Inocula made from 333 g of faeces gave higher values of OMD than that prepared from 83 g of faeces and was used in subsequent studies. When a 48-h acid pepsin digestion, the second stage of the Tilley and Terry (1963 ) technique, was included, the OMD values and the ease of filtering of undigested residues were increased. The second experiment compared digestibility determined with inocula produced from faeces with that produced from rumen liquor. The OMD of a ryegrass hay determined with an inoculum prepared from faeces was 0·468 compared with 0·528 when using an inoculum prepared from rumen liquor. The third experiment investigated the accuracy of estimating the OMD of eight contrasting forages determined using rumen liquor from three sheep ( y ) and faeces from two cows ( x ). All regressions were significant ( P  < 0·001) and had residual standard deviations (r.s.d.) of between ±0·019 and ±0·022. The final study compared faeces collected from cattle fed with either hay or concentrates. The OMD of forage was higher from the hay-fed animals, but the r.s.d. values of the regressions were similar. It was concluded that cattle faeces shows potential as an alternative to rumen liquor collected from rumen-fistulated sheep for use in the in vitro digestibility assay of forages.     

Physicochemical characteristics of flours of faba bean as influenced by processing methods

Wet- and dry-processing with and without heating treatments were used to dehull faba beans for preparation of flours from the cotyledons. Flour qualities were assessed by levels of tannin and trypsin inhibitor and other measures of proximate composition. High roasting temperature and shorter process time that improved the recovered cotyledon yields were verified significant by path analysis methodologies. In turn, the higher cotyledon recoveries correlated with higher protein levels and inversely with the measured tannin levels. Ash reductions were correlated to the wet processing options in hull removal while reductions in the insoluble dietary fiber were notably influenced by level of heating temperatures applied. Trypsin inhibitor levels ranged from 42 to 56% of the original with reductions tied to applications of wet and/or heat processing in each case improved by increased durations and temperatures of treatments.     

The stability of carotene in vegetable foods and forages

Summary Pure carotene is unstable in air. In seeds, carrot roots and fruits the carotene is relatively stable while these parts of plants remain alive. In some conditions the carotenoids in detached fruits and carrots increase during a few weeks in storage. When leaves are extensively injured the carotene is quickly oxidized under the influence of an enzyme system. The enzyme is abent from carrots and fruits but is found in all leaves. Indeed chlorophyll has not yet been found without the enzyme in any parts of plants. Even after the enzyme is destroyed by heat and dehydration, carotene is lost, slowly in the dark and faster in light. Carotene is similarly lost from dehydrated carrots. The rate of oxidation of carotene in dried vegetables and forage crops during storage depends upon conditions. Low temperature, antioxidants and high moisture favour retention. If oxygen and light are excluded carotene is stable indefinitely. Thus carotene is well preserved in frozen, gaspacked, vacuum-packed or canned vegetables and fruits.

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Zusammenfassung Krystallinisches Carotin ist nicht stabil an der Luft. In Samen, Karotten und Obst ist das Carotin relativ stabil, solange diese Pflanzenteile lebend sind. Die Konzentration der Carotinoide im geernteten Obst und in Karotten vergrössert sich manchmal während einer Spanne von einigen Wochen. Wenn die Blätter verletzt sind, wird das Carotin durch die Wirkung eines Enzymsystems rasch oxydiert. Dieses Enzym findet man nicht in Karotten und Obst, ist aber in allen Chlorophyll-enthaltenden Pflanzen gefunden worden. Wenn das Enzym durch Hitzeeinwirkung und durch Trocknen inaktiviert ist, verschwindet das Carotin auch, aber viel langsamer, wenn die Blätter im Dunkeln gehalten werden, etwas schneller im Licht. In getrockneten Karotten verschwindet das Carotin in ähnlicher Weise. Das Mass des Carotin-Verlustes in Trockengemüse und in Futtermitteln hängt von den Lagerbedingungen ab. Antioxydantien, niedrige Temperatur und hohe Feuchtigkeit haben guten Einfluss auf die Carotin-Erhaltung. Wenn Sauerstoff und Licht ausgeschlossen werden, ist das Carotin unbeschränkt stabil. Daher ist das Carotin gut praeserviert, wenn Gemüse und Obst in Dosen, oder schnellgefroren, gasgepackt oder vakuumgepackt konserviert werden.

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Résumé Le carotène pur est instable dans l'air. Dans les graines, racines de carottes et fruits, le carotène est relativement stable tant que ces différentes parties de la plante restent vivantes. Dans de certaines conditions, les caroténoïdes, dans les fruits et carottes séparés de la plante augmentent durant quelques semaines. Quand les feuilles sont abîmées, le carotène est rapidement oxydé, sous l'influence d'un système enzymétique. Cet enzyme est absent des carottes et fruits, mais se trouve dans toutes les feuilles. En effet, la chlorophylle n'a jamais encore été trouvée, sans cet enzyme, dans quelque partie de la plante que ce soit. Même après que l'enzyme ait été dètruit par chaleur et déshydratation, le carotène disparaît, lentement à l'obscurité, plus rapidement à la lumière. Le carotène disparaît de même, à partir de carottes déshydratées. La vitesse de l'oxydation du carotène, dans les végétaux morts et les fourrages, durant le magasinage, dépend de diverses conditions. Basse température, antioxydants et humidité élevée favorisent la conservation. Si on élimine l'oxygène et la lumière, le carotène est indéfiniment stable. Ainsi le carotène est bien conservé dans les végétaux et fruits congelés, sous atmosphère inerte ou stérilisés en boîte.

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Member of the scientific staff of the Agricultural Research Council.     

Effects of a range of fungicides used to control rust (Uromyces viciae-fabae) on spring-sown field beans (Vicia faba) in the UK

In two years a range of fungicides was used to control rust (Uromyces viciae-fabae) on spring-sown field beans (Vicia faba). In 1984 fenpropimorph, maneb, mancozeb, maneb plus mancozeb, propiconazole, thiram, triadimefon and zineb-polyethylene thiuram disulphide plus tridemorph were applied once or twice and compared with no fungicide. In 1985 the experiment was repeated with the addition of benodanil. In 1984 there was very little rust or other foliar disease and the effects of treatments on yield were small. In 1985 rust was first found in late June and became severe on untreated plots in August. All the fungicides reduced the incidence of rust but the amount of control differed with frequency of application and on different dates of disease assessment. In 1985 chocolate spot (Botrytis fabae) also became severe in late August. All the fungicides reduced chocolate spot but maneb plus mancozeb was the most effective. In 1985 yields were increased from 5 · 6 to 7 · 7 t/ha by maneb plus mancozeb applied once. Other fungicides gave smaller yield increases. Yield increases given were attributable mainly to control of rust but partly to control of chocolate spot. Yield increases given by non-systemic fungicides came mainly from increases in the weight of individual grains; those yield increases given by systemic materials came, in addition, from better pod retention.     

Cotyledon thermal behavior and pectic solubility as related to cooking quality in common beans

The characteristic of proteins, starch and pectic substances in cotyledons of two bean cultivars varying in cooking time were determined to investigate their possible contribution to bean cooking quality. Both cultivars showed the same enthalpies of starch gelatinization but different protein denaturation enthalpies. The proportion of hot water soluble pectins was higher in Michigan, the cultivar with the lower cooking time, than in Ojo de Cabra, the cultivar with the higher cooking time. These results were not due to differences in pectin methylation or in the ratio of monovalent to divalent cations in the tissue, suggesting that in fresh beans the β-elimination reaction is not the sole or predominant route of thermal pectin degradation. Overall, this study indicates that varietal differences in bean cooking quality may be reflections of the rate of pectin loss during soaking/heating and that the thermal properties of starch and protein fractions seem to have a minor contribution. Researchers involved in this study propose that in fresh beans, the thermal pectin loss results from a two step mechanism: pectin enzymic breakdown during the bean soaking followed by thermal solubilization rather than β-elimination during the bean heating.     

Effect of Egyptian cooking methods of faba beans on its nutritive value,dietary protein utilization and iron deficiency anemia 1. The role of main technological pretreatments

In order to study the effects of main technological pretreatments practised for preparing Egyptian faba bean products, i.e. decortication as well as soaking and germination followed by dehulling on the nutritional value, series of experiments were carried out. Such pretreatments had a significant effect on the changes in the chemical composition of faba beans. The proportion of the removed hulls reached generally about 14%. Data revealed also pronounced improvements on the nutritive value as a result of all studied pretreatments, especially germination being the most effective. Chemical scoring of all determined essential amino acids was >60, except methionine and cystine showed the lowest score (<20). Germinated seeds had the highest chemical score for the restricting amino acids beside the lowest GDR value [Grams consumed of product to cover the daily requirements for adult man in protein (63 g) and in energy (2900 kcal)]. All pretreatments caused a significant decrease in the antinutritional factors, especially soaking followed by dehulling, whereas decortication led to a significant increase in phytic acid content.     

Water retention and flow behaviours of protein isolates from peas

Protein isolates from pea flour were prepared by extraction of protein at pH 7.0 or 9.0 which was followed by precipitation as isoelectric isolates or as proteinates. After spray-drying, chemical composition, water retention capacities, thickening properties, and flow behaviours were determined and compared to those of a soybean protein isolate (Supro 620).