AN OVERVIEW OF COMPARISON BETWEEN WHEAT RUSTS MYCOFLORA IN INDIA WITH GLOBAL SCENARIO

Wheat rusts are the oldest plant disease known to human and caused by Puccinia species. Puccinia species are the main constraints in wheat production wherever wheat is grown. Early literatures mention these devastating diseases and their ability to destroy entire wheat crops. These wheat rust pathogens are highly transmissible through air current in both cases, primary and secondary infections. Primary infection occur through alternate host developing spore (Aeciospores) and secondary infection caused by wheat (primary host) developing spore (Uredospores). Secondary infection results epidemics, several time as globally occurrence. Ecologically, the persistence of rusts as a significant disease in wheat can be attributed to specific characteristics of the rust mycoflora. Their ability to spread aerially over the large distance, production of urediospores in enormous number and evolving new pathotypes, makes the management of wheat rusts a very daunting task. These characteristics include a capacity to produce a large number of spores which can be wind disseminated over long distances and infect wheat under favorable environmental conditions and the ability to change genetically, thereby producing new races with increased aggressiveness on resistant wheat cultivars. KEY WORDS: Wheat Rust, Puccinia, Rust Mycoflora, Stem Rust, Leaf Rust, Stripe Rust

Effect of graded levels of wheat-based dried distillers’ grains with solubles on rumen fermentation in finishing cattle

A 4 × 4 Latin square experiment using ruminally cannulated heifers (388 ± 25 kg, mean ± SD) was conducted to evaluate the effects of graded levels (0, 7, 14, 21% DM basis) of wheat-based dried distillers’ grains with solubles (DDGS) on rumen fermentation characteristics and eating behaviour of cattle fed barley-based diets. Mean rumen pH at cutoff values of pH 5.8 or less (P = 0.02) and pH 5.5 or less (P < 0.01) and pH area between 5.2 and 5.5 (P = 0.02) decreased cubically as DDGS content increased with maximum pH at 2.6% and minimum pH at 14.7% DDGS inclusion levels. A cubic effect of DDGS inclusion level (P = 0.03) was noted for time below pH 5.2 where local minima and maxima were found at 2.9 and 15.0% DDGS. Ammonia N (P < 0.01) and the acetate:propionate ratio (P = 0.01) increased, while propionate decreased (P < 0.01) linearly as DDGS content increased. It was concluded that despite the high fibre, low starch nature of wheat-based DDGS, substitution for barley did not improve the acidic rumen fermentation conditions associated with feeding barley-based finishing diets. Key words: Wheat dried distillers’ grains with solubles, rumen fermentation, feeding behaviour, sub-acute ruminal acidosis

Near-infrared versus visual sorting of Fusarium-damaged kernels in winter wheat

Fusarium head blight (scab) of wheat, caused by Fusarium graminearum, often results in shriveled and/or discolored kernels, which are referred to as Fusarium-damaged kernels (FDK). FDK is a major grain grading factor and therefore is routinely determined for purposes of quality assurance. Measurement of FDK is usually done visually. Visual sorting can be laborious and is subject to inconsistencies resulting from variability in intra-rater repeatability and/or inter-rater reliability. The ability of a single-kernel near-infrared (SKNIR) system to detect FDK was evaluated by comparing FDK sorted by the system to FDK sorted visually. Visual sorting was strongly correlated with sorting by the SKNIR system (0.89 ≤ r ≤ 0.91); however, the SKNIR system had a wider range of FDK detection and was more consistent. Compared with the SKNIR system, visual raters overestimated FDK in samples with a low percentage of Fusarium-damaged grain and underestimated FDK in samples with a high percentage of Fusarium-damaged grain. Key words: Wheat, Fusarium head blight, Fusarium-damaged kernels, single-kernel near-infrared

Nutrient digestibility, performance and carcass traits of growing-finishing pigs fed diets containing dried wheat distillers grains with solubles

Seventy-two pigs were fed graded levels of wheat distillers grains with solubles (DDGS). During the growing period, gain, intake and nutrient digestibility declined (P < 0.01) as wheat DDGS increased. During the finishing period, performance was unaffected by wheat DDGS. At slaughter, dressing percentage and loin lean declined (P <0.01). Key words: Wheat distiller's dried grains with solubles, pigs, performance, digestibility, carcass traits

Effect of cultivar and enzyme supplementation on nutrient availability and performance of broilers fed Maritime Canadian wheat

The feeding value of wheat is affected by the content of soluble non-starch polysaccharides (NSP), which varies among cultivars and the environment in which they are grown. Dietary enzymes can reduce the negative effects of NSP and improve the apparent metabolizable energy (AME) content of the wheat. This study examined differences in feeding value of four wheat cultivars grown in 2 crop years in the Maritime provinces of Canada and the need for enzymes. In a growth trial, diets containing one of the Maritime wheats or corn were fed with or without commercial enzymes containing, for wheat-based diets a mixture of xylanase and protease, and for corn-based diets a mixture of xylanase, protease, and amylase. In a broiler chick bioassay, diets containing 80% wheat were fed with or without a commercial enzyme with xylanase and protease activities. Enzymes significantly lowered body weight gain of birds fed Walton wheat in the second year, and improved the grower feed conversion ratio of birds fed Norboro wheat. Enzyme supplementation significantly improved apparent metabolizable energy and digestibility of crude protein. The AME content did not appear to be a direct indicator of performance. There were significant differences in AME content among the wheat samples. Enzymes generally did not improve performance in this study, possibly due to the relatively low in vitro viscosity values of these samples. Maritime wheats were equal or compared favourably with the sample of wheat from Western Canada and to locally obtained corn. Key words: Wheat, broiler performance, apparent metabolizable energy, enzyme

Rotational yield and apparent N benefits of grain legumes in southern Manitoba

Knowledge of rotational N benefits of grain legumes can assist in crop rotation planning and N fertilizer management. Four annual grain legumes were tested in Manitoba field trials over 3 yr. Field pea provided the largest and most consistent apparent N benefit to a succeeding wheat crop; soybean provided relatively little N benefit. The apparent N benefits of chickpea and dry bean were inconsistent, although chickpea shows greater potential in dry conditions. Key words: Wheat rotations, N credit, crop rotation

Effect of harvesting time on incidence of seed-borne Fusarium spp. in spring wheat in eastern Ontario

The effect of five harvesting times on the incidence of seed-borne Fusarium spp. was examined using three spring wheat cultivars grown at two locations in eastern Ontario in 1999 and 2000. Twelve Fusarium spp. were isolated from 3831 of the 24 000 seeds, which were surface disinfected and plated onto modified potato dextrose agar. Fusarium sporotrichioides Sherb., F. graminearum Schwabe, F. poae (Peck) Wollenw., F. equiseti (Corda) Sacc., and F. avenaceum (Fr.) Sacc. were the most frequently isolated species and were isolated from 6.8, 3.7, 2.8, 1.8, and 0.6% of total seeds, respectively. The remaining species, F. acuminatum Ellis & Everh., F. crookwellense Burgess, Nelson & Toussoun, F. culmorum (W.G. Sm.) Sacc., F. oxysporum Schlecht., F. sambucinum Fuckel, F. solani (Mart.) Sacc., and F. tricinctum (Corda) Sacc., collectively infected only 0.3% of total seeds. The incidence of F. graminearum, F. sporotrichioides, and total Fusarium spp. increased about twofold, from 1.7, 3.9, and 9.5% in seed harvested very early to 5.5, 8.7 , and 19.8%, respectively, after delayed harvest. Also, F. poae had a significantly lower incidence at very early and early harvest times compared to normal or later harvest dates. Incidence of total other Fusarium spp., percentage of fusarium damaged kernels (FDK), and deoxynivalenol (DON) concentration were relatively low in the harvested grain and not affected by harvesting time. Of the three cultivars used, AC Barrie had the lowest incidence of Fusarium spp., FDK, and DON concentration in the grain; Quantum was intermediate; and Celtic had the highest. Variations in the incidence of Fusarium spp. for location and year were observed and likely related to levels of inoculum and weather conditions before and during harvesting times. Key words: Wheat, grain quality, farinograph, protein concentration, N management, cultivar selection and marketing

The effect of extra-strong gluten on quality parameters in durum wheat

Durum wheat (Triticum durum L.) cultivars with extra-strong gluten characteristics have become a unique quality type preferred by several domestic and international pasta processors. Durum genotypes with extra-strong gluten characteristics were compared to conventional gluten strength types to determine the relative levels of gluten strength and the importance of this characteristic in pasta quality. All extra-strong genotypes had similar gluten index levels that were significantly greater than cultivars traditionally grown in western Canada. For improved endproduct texture, the level of gluten strength appeared to be less important than protein content and wet gluten weight, which were the variables most closely linked to spaghetti viscoelasticity. The general positive relationships between texture and protein content of high temperature dried spaghetti followed the findings of previous studies. However, extra-strong gluten genotypes with lower protein content could not match the superior texture characteristics obtained with higher protein conventional strength cultivars. When dried at 70°C, pasta texture, measured as viscoelastic properties, was dependent on gluten strength rather than protein content, so the higher gluten strength types had an advantage even at lower protein levels. While the relationship between gluten strength and texture of low temperature dried products has been noted previously, this study shows that this relationship is somewhat dependent on having a range of gluten strength types present. Although there was a positive relationship between spaghetti viscoelasticity and protein content, and between pasta disc viscoelasticity and gluten strength, there appeared to be a negative relationship between gluten strength and protein quantity factors. Scatter plot matrices of the means indicated the negative correlation was likely due to clustering of similar genotypes, but that a positive relationship was apparent within the extra-strong gluten types. Key words: Wheat (durum), Triticum durum, pasta quality, extra-strong gluten

Defining the effects of wheat type, water inclusion level, and wet-diet restriction on variability in performance of broilers fed wheat-based diets with added water

The objectives of the study were to determine if feed conversion ratio (FCR) in broilers fed wet Hard Red Spring (HRS) as compared to Durum-based wheat diets could be reduced by: (a) diluting HRS with Durum wheat, (b) pelleting of the wheat, (c) adding different levels of water to the diet, or (d) restricting intake of diets to which water was added. Three wheat types [Durum, HRS and a Composite (50:50) sample] were ground, with one portion of the ground grain being pelleted and reground before both forms of each wheat type were included at 80% of a basal broiler diet. All diets were supplemented with a commercial wheat enzyme and fed as a mash. Each of the six diets was fed in one of four feed regimens: DRY (as is); WET1.2 (DRY with 1.2 g water g-1 feed); WET0.6 (DRY with 0.6 g water g-1 feed); and RWET1.2 [WET1.2 diet treatment restricted-fed to 120% of the previous day’s DRY feed intake (on an air-dried basis) for each diet type]. This provided 24 dietary treatments each fed to six cages of five male broilers from 1 to 21 d of age. The wet diets were prepared daily. Among the feed regimens WET1.2 resulted in the significantly highest 21-d body weight. The significant increase in feed intake and FCR of HRS-based diets with added water was reduced significantly by diluting this wheat with Durum wheat. Feeding the unpelleted Composite wheat sample significantly improved growth rate over either wheat alone, presumably due to an improved balance of nutrients. Pelleting significantly reduced intake of wet HRS-based diets and increased apparent metabolisable energy (AME), resulting in a marked reduction in FCR compared to unpelleted diets. There was some value in using less water in HRS-based, but not in Durum-based diets, with respect to FCR and metabolisable energy retention. Physical restrictions of feed intake reduced FCR of wet (WET1.2) unpelleted HRS diets, but did not affect the same diet when wheat was pelleted. Further work is required to establish the optimum consistency of feed in a wet form to maximize feed intake and growth while minimizing FCR. Key words: Wheat, wet feeding, enzymes, feed intake, broilers

Effect of pelleting and enzyme supplementation on variation in feed value of wheat-based diets fed to broiler chicks

The effect of wheat cultivar, pelleting, and enzyme supplementation was measured with a broiler chick bioassay comparing differences in feed intake, growth, FCR and metabolisable e nergy (ME) level. Samples of two wheat cultivars from each of six classes were ground and were either unpelleted or pelleted and ground before including (80%) in mash diets with or without enzyme (Avizyme 1302). Two common control diets were fed in the two bioassay series required to evaluate the 48 diets. Each diet was fed to four cages of six male broilers from 4 to 17 d of age. Apparent metabolisable energy (AME) was determined on excreta collected at 16 d of age. There was more than a 25% difference in feed intake among the 48 diets; the largest contribution of the variation was due to wheat cultivar. Feed intake was significantly increased by enzyme addition and decreased by pelleting. Variation in feed intake explained more than 70% of the variation in body weight and had only a minor association with determined AME. The AME of all wheat samples, except the two Durum wheats, was increased by both enzyme supplementation and processing. The increase in AME with processing may represent an anomaly of using different bioassay series to measure unpelleted and pelleted wheat samples or it may represent changes in AME of all wheat samples, except Durum wheats, with storage after harvesting. The relative AME and FCR measurements for the 12 wheat samples were similar whether the wheats were pelleted or not. However, there was no relationship between measurements of feed intake when the different cultivars of unpelleted and pelleted wheat were compared. The marked variation in feed intake and growth rate of broilers fed different cultivars of wheat continues to be a concern as it suggests that other factors may limit intake and prevent the broiler from obtaining the required levels of nutrients from the diet. Key words: Wheat, feed processing, enzymes, feed value, broilers