Lots Of Barley Research Articles

Radicle Emergence Test Standardization to Forecast Field Emergence and Seed Vigour in Hordeum vulgare L.

A study was conducted to discover the use of RE single counts in testing vigour and predicting seedling establishment in seed lots of barley (Hordeum vulgare L.). We compared the RE counts at 20 °C at intervals of 16, 24 and 40 h and also at 15 °C for 24 h, with electrical conductivity (EC), germination percentage (GP), field emergence (FE), and mean germination time (MGT), using 8 seed lots of barley. Radicle emergence counts at 15 °C for 24 h and at 20 °C for 16, 24 and 40 h showed a high correlation with two parameters of seed vigour (MGT and FE), and their correlation coefficients were greater than 0.70 (p < 0.05). Usable correlation coefficients were realized after 24 h both at 15 °C and 20 °C. The results of the test showed that RE single counts are useful in testing vigour in barley seeds. The results also proved that single counts of radical emergence (RE), were useful in indicating the potential of emergence in barley seedlings.

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English

In vitro production of trichothecenes and Zearalenone by Fusarium isolates from equatorial barley (Hordeum vulgare L.) grown in Kenya.

Fusarium head blight (scab) is a devastating disease of wheat and barley throughout the world. The disease has been reported worldwide wherever cereals are grown, cutting across diverse ecological and geographical distribution. In addition to being pathogenic to plants, which may cause severe crop yield reduction, many Fusarium species are also capable of producing mycotoxins deleterious to human health as secondary metabolites. Fusarium toxins are commonly detected in wheat, barley, maize, rice and beer. Traditionally malted barley (Hordeum vulgare L.) is the principal ingredient in clear beer and Fusarium toxins incidences are of major concern. Moreover, the spent grain from the brewing industry is used as feed and presence of mycotoxins can lead to harmful effects on domestic animals and also find a way into the human food chain. Studies carried out in Kenya have revealed presence of various Fusarium species with ability to produce mycotoxins and presence of Fusarium toxins in wheat and maize and beer. Based on the ubiquitous nature of Fusarium mold and the fact that barley production takes place in maize and wheat growing areas, this study set out to investigate the occurrence of Fusarium molds in Equatorial barley grown in Kenya and the ability of the isolates to produce selected mycotoxins. Grain samples were obtained from newly delivered barley lots originating from two regions and stored grain awaiting malting after break of dormancy from Kenya Maltings Ltd., Nairobi. The Fusarium isolates were identified to species level based on cultural and morphological characteristics. Additionally, they were screened in-vitro on rice cultures for their ability to produce Type A trichothecenes (T–2 toxin, HT–2 toxin, Diacetoxyscirpenol), Type B trichothecenes (deoxynivalenol and nivalenol) and Zearalenone. Samples from all sources were contaminated with Fusarium, but at varying magnitudes - 50%, 33.3% and 25% for barley kernels originating from Timau, Olchoro and in-storage grain with no common history of origin, respectively. The distribution of the species showed some regional specificity. F. graminearum and F. poae predominated in kernels sourced from Olchoro region. All strains of F. graminearum produced both deoxynivalenol and zearalenone. F. poae strains and F. chlamydosporum did not produce detectable amounts of the screened mycotoxins. However, two inconclusively identified isolates of Fusarium spp. isolated from Timau samples produced deoxynivalenol only. The study revealed that a number of toxigenic Fusarium spp. do occur in Equatorial barley grown in Kenya.

In vitro production of trichothecenes and zearalenone by fusarium isolates from equatorial barley (hordeum vulgare L.) grown in Kenya

Fusarium head blight (scab) is a devastating disease of wheat and barley throughout the world. The disease has been reported worldwide wherever cereals are grown, cutting across diverse ecological and geographical distribution. In addition to being pathogenic to plants, which may cause severe crop yield reduction, many Fusarium species are also capable of producing mycotoxins deleterious to human health as secondary metabolites. Fusarium toxins are commonly detected in wheat, barley, maize, rice and beer. Traditionally malted barley (Hordeum vulgare L.) is the principal ingredient in clear beer and Fusarium toxins incidences are of major concern. Moreover, the spent grain from the brewing industry is used as feed and presence of mycotoxins can lead to harmful effects on domestic animals and also find a way into the human food chain. Studies carried out in Kenya have revealed presence of various Fusarium species with ability to produce mycotoxins and presence of Fusarium toxins in wheat and maize and beer. Based on the ubiquitous nature of Fusarium mold and the fact that barley production takes place in maize and wheat growing areas, this study set out to investigate the occurrence of Fusarium molds in Equatorial barley grown in Kenya and the ability of the isolates to produce selected mycotoxins. Grain samples were obtained from newly delivered barley lots originating from two regions and stored grain awaiting malting after break of dormancy from Kenya Maltings Ltd., Nairobi. The Fusarium isolates were identified to species level based on cultural and morphological characteristics. Additionally, they were screened in-vitro on rice cultures for their ability to produce Type A trichothecenes (T–2 toxin, HT–2 toxin, Diacetoxyscirpenol), Type B trichothecenes (deoxynivalenol and nivalenol) and Zearalenone. Samples from all sources were contaminated with Fusarium, but at varying magnitudes - 50%, 33.3% and 25% for barley kernels originating from Timau, Olchoro and in-storage grain with no common history of origin, respectively. The distribution of the species showed some regional specificity. F. graminearum and F. poae predominated in kernels sourced from Olchoro region. All strains of F. graminearum produced both deoxynivalenol and zearalenone. F. poae strains and F. chlamydosporum did not produce detectable amounts of the screened mycotoxins. However, two inconclusively identified isolates of Fusarium spp. isolated from Timau samples produced deoxynivalenol only. The study revealed that a number of toxigenic Fusarium spp. do occur in Equatorial barley grown in Kenya.

Assessment of the loose smut fungi (Ustilago nuda and U. tritici) in tissues of barley and wheat by fluorescence microscopy and real-time PCR

Loose smut fungi of barley and wheat (Ustilago nuda and U. tritici, respectively) colonize the plant without causing obvious disease symptoms before heading. The availability of diagnostic methods to detect and follow the growth of these pathogens in the plant would therefore be highly advantageous for both resistance breeding and the development of effective seed treatments. Using seed lots of barley and wheat highly infected with loose smut, we studied the early establishment of the loose smut pathogens in the plant by fluorescence microscopy. In hand-cut sections stained with the fluorochrome Blankophor®, fungal hyphae were observed to invade the shoot apical meristem and leaf primordia during the first days after the onset of germination. At the first node stage the ear and leaf primordia were generally extensively colonized. Hyphae of U. nuda were also regularly observed in high density in the nodes. A protocol was developed for the specific amplification of U. nuda and U. tritici DNA extracted from infected plant tissue. PCR screening of U nuda in seedlings from infected and healthy seed lots was compared to ELISA, microscopy and ultimately head infection of mature plants derived from tillers of the tested seedlings. The results indicated that a prediction of loose smut infection by real-time PCR is possible at the second leaf stage, and that the assay is equally suited for use with spring and winter varieties of barley and wheat.

Levels of endogenous β-glucanase activity in barley affect the efficacy of exogenous enzymes used to supplement barley-based diets for poultry

To improve the nutritive value of barley-based diet for broilers, 2 experiments using 2 different barley lots were performed to evaluate the capacity of a mesophilic cellulase when fused to a β-glucan specific family 11 carbohydrate-binding module. The data revealed that the recombinant β-glucanase derivatives were not appropriate for feed supplementation because of a lack of stability at acidic pH levels. However, under the same experimental conditions, a commercial enzyme mixture improved the nutritive value of 1 of the cereal lots used. Analysis of the nutritive value of the 2 barleys revealed intrinsic differences in the levels of endogenous β-glucanase activity. These differences were extensively evident when the studies were expanded to a range of 64 barley lots. Thus, to clarify the effect of endogenous cellulases on the efficacy of exogenous β-glucanases used to supplement barley-based diets for poultry, 2 barley lots presenting low and high levels of endogenous plant cell wall-degrading enzymes were selected. These lots were used to prepare 2 barley-based diets, which were supplemented with or without a commercial enzyme product and fed to broiler chicks. The data revealed that the exogenous enzymes were effective when the basal diet presented low levels of endogenous β-glucanases but were unable to improve the nutritive value of the barley lot displaying higher β-glucanase activity. Thus, these studies suggest that levels of endogenous β-glucanases may affect the efficacy of exogenous enzymes used to improve the nutritive value of barley-based diets for broilers. The development of a quick β-glucanase assay that could be applied for cereal-based feeds may help identify those barley-based diets that are more responsive to the action of feed enzymes.

Effect of hot water treatments on the safety and quality of Fusarium-infected malting barley

Utilization of Fusarium-infected barley for malting may lead to mycotoxin contamination of malt and decreased malt quality. Hot water treatments may prevent or reduce safety and quality defects and allow use of otherwise good quality barley. We evaluated hot water treatments for preventing Fusarium growth and mycotoxin production while maintaining barley–malt characteristics. Four barley lots with varying deoxynivalenol (DON) concentrations were hot water-treated at 45 or 50 °C for 0, 1, 5, 12, and 20 min. Treated barley was malted in a pilot-scale malting unit. Barley and malt were analyzed for Fusarium infection (FI), germinative energy (GE), aerobic plate count (APC), mold and yeast count (MYC), and DON. Malt quality parameters included malt extract, soluble protein, wort color, wort viscosity, free amino nitrogen, alpha-amylase, and diastatic power. Significant decreases in FI occurred within 1 min at both 45 °C (41–66%) and 50 °C (51–69%) in all barley samples. Significant reductions in APC (1.0–1.8 log) and MYC (1.7–1.8 log) in barley were observed after 5 min at both temperatures. The largest reductions for DON were observed in malts prepared from barley treated with hot water at 45 °C (79–93%) and 50 °C (84–88%) for 20 min. GE and most of the malt quality parameters were only affected when barley was treated at 50 °C for 12 and 20 min. The results suggest that hot water treatments may offer the potential for treating mildly FHB infected malting barley.

Effect of electron-beam irradiation on the safety and quality of Fusarium-infected malting barley

Utilization of Fusarium-infected barley for malting may lead to mycotoxin production during malting and decreased malt quality. Electron-beam irradiation may prevent safety and quality defects and allow use of otherwise good quality barley. We evaluated electron-beam irradiation for preventing Fusarium growth and mycotoxin production while maintaining barley-malt quality characteristics. Four barley lots with varying deoxynivalenol (DON) concentrations were irradiated at 0, 2, 4, 6, 8, and 10 kGy. Treated barley was malted in a pilot-scale malting unit. Barley and malt were analyzed for Fusarium infection (FI), germinative energy (GE), aerobic plate counts (APC), mold and yeast counts (MYC), and DON. Malt quality parameters included malt extract, soluble protein, wort color, wort viscosity, free amino nitrogen, alpha-amylase, and diastatic power. FI, APC, and MYC decreased in barley with an increase in dosage. The APC and MYC for malts from barley exposed to 8–10 kGy were slightly higher than in other malted samples indicating that irradiation-resistant microflora could flourish during malting. Barley GE significantly decreased (3–15%) at 8–10 kGy. Although irradiation had no effect on DON in raw barley, DON decreased significantly (60–100%) in finished malts prepared from treated barley (6–10 kGy). Malt quality parameters were slightly affected by electron-beam radiation. The results suggest 6–8 kGy may be effective for reducing FI in barley and DON in malt with minimal effects on malt quality.

Persistence and Efficacy of Three Diatomaceous Earth Formulations Against <I>Sitophilus oryzae</I> (Coleoptera: Curculionidae) on Wheat and Barley

The insecticidal and residual efficacy of three diatomaceous earth (DE) formulations, Insecto, PyriSec, and SilicoSec, against Sitophilus oryzae (L.) on barley and wheat was assessed. For this purpose, 4-kg lots of barley and wheat were treated with the above-mentioned DE formulations, in three dose rates (0.75, 1, and 1.5 g/kg grain) and stored at 26 degrees C. Samples of these lots were taken at the day of storage, and every 45 d, until the completion of a 450-d period of storage. Bioassays were conducted by exposing S. oryzae adults to these samples, at 26 degrees C and 57% RH. In these bioassays, the DE efficacy was evaluated by recording adult mortality after 24 h, 48 h, 7 d, and 14 d of exposure on the treated grains. After the 14-d count, all adults were removed, and the samples were left at the same conditions for an additional 45 d, to evaluate the capacity for progeny production in the treated grains. Adult mortality after 14 d of exposure was exponentially decreased with time. During the first 270 d of storage, mortality was > 90%, and progeny production was < 1 adult per sample, whereas after 270 d a gradual decrease in adult mortality occurred, with a resulting increase in progeny production. Generally, the three DE formulations tested were equally effective against S. onyzae adults. During the first 270 d of storage, the DE formulations were equally effective on both grains tested, but from 315 d of storage and on, S. oryzae mortality was higher on barley than on wheat. At this interval, progeny production was gradually increased, especially on grains treated with the lowest DE dose rate. However, even this rate caused a satisfactory level of mortality (> 90% after 14 d of exposure) during the first 270 d of storage.

Effect of Kiln Schedule on Micromalt Quality Parameters

Four barley cultivars from four environments were micromalted and kilned using three kilning schedules as part of an evaluation of the effect of kilning schedules on malt quality parameters. Kilning schedules significantly affected malt diastatic power, α-amylase activity, soluble protein, the soluble protein/total malt protein ratio, wort viscosity, wort color, and malt moisture. Lower diastatic power and α-amylase activity, increased wort viscosity, and darker wort color were attributable to the higher temperatures used in two of the kilning schedules. The lowest temperature schedule produced malt with the greatest diastatic power and α-amylase activity, lightest wort color, and lowest wort viscosity. Barley cultivars did not respond uniformly to the different temperature applications in terms of diastatic power, wort viscosity, and wort color. Robust barley obtained from five commercial maltsters was micromalted and kilned using high and low temperature schedules. The micromalts were analyzed and compared with commercial malts produced from the corresponding lots of barley. Micromalt samples produced using the high-temperature kilning schedule and the commercially prepared malts exhibited similar results for diastatic power, α-amylase activity, wort color, soluble protein, and the soluble/total protein ratio. Lower fine-coarse extract difference and wort viscosity were observed for the commercial malt samples.

Effect of β-glucan, starch, and fibre content and steam vs. dry rolling of barley grain on its degradability and utilisation by steers

Six lots of barley containing 3.5–4.8% β-glucans, 56.5–65.6% starch and 5.7–9.7% acid detergent fibre (ADF) were processed by either dry or steam rolling and fed to two groups of 60 steers in a 6 × 2 × 2 factorial experiment designed to assess the effects of these components in commercially available barley on the performance of feedlot cattle. There were no detectable differences ( P > 0.05) in daily gain (1.49–1.57 kg day −1), dry matter (DM) intake (9.09–9.77 kg day −1) or DM: gain ratio (5.85–6.35) between steers fed different lots of barley. However, significant ( P < 0.04) correlations were detected between DM: gain ratios and barley starch and ADF content ( R 2 = 0.69andR 2 = 0.90, respectively). The percentage of DM which disappeared from the barley during a 24 h in sacco incubation was negatively related to the DM: gain ratio ( R 2 = 0.83; P = 0.01. Apparent digestibilities of β-glucans, starch and ADF in the whole tract of steers were 98.6%, 98.1% and 29.1%, respectively. Steam rolling of barley had no influence ( P > 0.1) on any aspect of steer performance. It was concluded that information on the ADF content of barley would be useful in predicting nutritive value and that steam rolling, relative to dry rolling, did not improve growth rate or feed efficiency of growing-finishing cattle.

Chemical and nutritional evaluation of airtight storage of high-moisture barley and high-moisture barley treated with lactobacilli or lactobacilli and yeast

Barley was harvested at moisture contents of 36, 25 and 23% and infected with storage-associated moulds. Part of each lot of barley was also treated with lactobacilli or lactobacilli and yeast before being stored in airtight pilot silos. During storage the contents of starch, crude protein and β-glucans in the nine lots of barley remained fairly constant while the solubility of these components changed, especially in the barleys with 36% moisture. Treatment of the barleys with protecting microorganisms did not, to any large extent, influence the content or solubility of crude protein, starch or mixed-linked β-glucans during storage. Barley harvested at 36% moisture had higher extract viscosity and a higher dry matter disappearance in vitro than barley harvested at 23% moisture. Airtight storage diminished extract viscosity but had little effect on dry matter disappearance in vitro. Live weight of chickens at Days 14 and 21 was not significantly influenced by type of storage (dry or airtight) or microbial protection of the airtight stored 25% moisture barley. β-Glucanase supplementation significantly increased live weight at both Days 14 and 21. Feed conversion efficiency with airtight-stored high-moisture barleys was significantly improved by β-glucanase supplementation.

Effects of Barley Variety, Test Weight and Physical Form on Feeding Value of Barley for Swine

Three experiments involving 623 growing-finishing pigs were conducted to evaluate the effects of barley cultivar and test weight on animal and carcass characteristics. Despite the variation in CP and acid-detergent fiber content of the barley cultivars utilized in Exp. I, there were no differences (P>.10) in performance or carcass measurements. In addition, performance of pigs receiving pelleted barley-based diets was not different (P>.10) from that of pigs receiving the meal-form corn-based diet. There were no differences in performance (P>.10) among the barley cultivars or between the barley-based diets and the corn-based diet in Exp. II. However, differences were noted for dressing percentage (P<.05) and percent lean (P<.01) in Exp. II while no differences (P>.10) were noted for hot carcass weights, adjusted backfat, adjusted loin eye area and quality score. Azure barley samples having test weights of 50 and 63 kg/hl (39 1/2 and 49 1/2 Ib/bu) were mixed to provide barley lots of various test weights in Exp. III. When fed in meal form, ADG declined and F/G increased as barley test weight declined. The effects of declining test weight were of lower magnitude when the barley-based diets were fed in the pelleted form. Pigs receiving corn-based diets or pelleted barley-based diets had similar ADG and F/G values when the barley had a test weight in excess of 59 kg/hl (46 Ib/bu). In general, carcasses from pigs fed barley-based diets were more desirable than carcasses from pigs receiving corn-based diets. Live shrink of barley-fed pigs was not greater than that of pigs fed diets based on corn until test weight of the barley declined below 56 kg/hl. These data demonstrate that pelleted barley-based diets can support performance comparable to that obtained with corn-based diets when both contain equal and adequate levels of available lysine, available methionine plus cystine and available phosphorus.

Fate of ochratoxin A and citrinin during malting and brewing experiments.

The fate of ochratoxin A and citrinin during malting and brewing processes was studied by the use of naturally contaminated lots of barley, as well as by the addition of crystalline toxins to the mash. Complete degradation was observed for ochratoxin A from moderately contaminated barley lots and for citrinin added to mash. The use of highly contaminated barley resulted in transmission of ochratoxin A into the beer, but only 2 to 7% of the initial content was detected, corresponding to levels of 6 to 20 mug of ochratoxin A per liter of beer. Barley lots with this high ochratoxin contamination (1,000 to 5,000 mug/kg) will be easily detected and, therefore, because of pronounced deterioration, should be rejected during inspection upon admittance to the breweries.

Fate of Ochratoxin A and Citrinin During Malting and Brewing Experiments

The fate of ochratoxin A and citrinin during malting and brewing processes was studied by the use of naturally contaminated lots of barley, as well as by the addition of crystalline toxins to the mash. Complete degradation was observed for ochratoxin A from moderately contaminated barley lots and for citrinin added to mash. The use of highly contaminated barley resulted in transmission of ochratoxin A into the beer, but only 2 to 7% of the initial content was detected, corresponding to levels of 6 to 20 mug of ochratoxin A per liter of beer. Barley lots with this high ochratoxin contamination (1,000 to 5,000 mug/kg) will be easily detected and, therefore, because of pronounced deterioration, should be rejected during inspection upon admittance to the breweries.

The feed increment method for evaluating the net energy of feedstuffs for milk production

A feeding-trial procedure was employed as a means for estimating the net energy value of feedstuffs for milk production, using an adaptation of the feed increment principle. The reported observations were made over a period of three years in four trials with Latin-square designs. Basal rations made up of 70 per cent alfalfa and 30 per cent barley were tested against increments of alfalfa hay, barley, dried beet pulp, dried beet pulp with molasses, dried beet pulp with concentrated Steffen’s filtrate, and milo. Results indicated that the procedure could be useful for routine evaluation of feeds. Repeatability appeared encouraging as shown by net energy values of 71.8, 68.4 and 68.8 mcal/100 lb. dry matter, determined with three different lots of barley in as many years. The main problem yet to be solved is the determination of milk energy equivalent of liveweight change. In this regard the greatest source of error was the estimating of liveweight change.

THE USE OF SEQUENTIAL SAMPLING IN EMBRYO TESTS FOR LOOSE SMUT IN BARLEY SEED

One hundred and forty lots of barley seed were subjected to an embryo test for the mycelium of Ustilago nuda (Jens.) Rostr. Ten samples of 100 embryos were examined from each lot. It was found that the use of sequential sampling, instead of single or double sampling, in making routine tests for loose smut in barley seed, would result in a considerable saving of time and effort as far as determining whether seed stocks contain more or less than the percentage of smut set as the limit of tolerance. However, if the growers require a more exact knowledge of the level of infection in their stocks of seed, it would be preferable to examine 1,000 embryos from each stock, using the single sampling method.