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Efforts in grasspea (Lathyrus sativus) improvement have increased since the development of lines that are very low in the neurotoxin Beta-N-oxalyl-L-alpha-beta-diamino propionic acid (ODAP); also referred to as Beta-N oxalyl-amino-L-alanine (BOAA). Many programs now address several related aspects of improvement simultaneously. These include reduced ODAP concentrations, insect and disease resistance, nitrogen fixation, agronomic practices, fodder and forage production, and components for increased yielding ability. The coordinated, multidisciplinary approach now being applied to the genetic improvement of grasspea should allow the potential of this largely neglected grain legume to be fully realized.  相似文献   
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The impact of fly ash on the chemistry of the River Yamuna was studied. By-products from a 200 MW capacity I.P. thermal power station on the west bank of the River Yamuna, Delhi are largely from coal combustion (fly ash) and are disposed of as a slurry to off-site ash ponds. Many elements associated with fly ash are soluble and become available to the biota. A two-year survey was made of the seasonal variations in limnochemical features in the non-impacted and the impacted segments of the river receiving fly ash effluent and the ash treatment ponds. Conductivity, TDS, DO, hardness, sulphate and nitrate increased significantly in the receiving waters over background values. The reverse was noticed for free CO2, alkalinity and phosphate. Changes in some other parameters were insignificant. Fly ash effluents from the ash ponds significantly increased the concentration of some elements, viz., Al, Sb, Bi, Cd, Cr, Co, Li, Mn, Mo, K, Si, and Zn in river water. Generally, the highest concentration of most parameters were recorded in the ash ponds. This investigation was helpful in assessing the effect of wet ash disposal on the river limnology and understanding the solubility of various elements in the ash ponds.  相似文献   
4.
Effect of corn degermination mill parameters (clearance between mill plates and rpm) were assessed on the broken germ and number of whole kernels in mash so as to optimize the cracking procedure for the intermittent milling and dynamic steeping (IMDS) process. The dynamic steep time and number of intermittent milling stages for the IMDS process were also optimized for maximum starch recovery. A comparison was made between the IMDS and the conventional steeping process for fraction yields. A clearance of 0.45–0.48 cm between the plates gave the most optimum processing conditions (minimum broken germ and least amount of whole kernels in mash after cracking). Effect of rpm on germ damage and kernel cracking was not significant when optimum clearance between the degermination plates was maintained. Two stages of intermittent milling with a dynamic steep time of 30 min or higher was recommended because it produced the highest yield of starch and germ. Comparison of the IMDS process with the conventional wet‐milling process showed that starch and gluten yield increased by 1.6 and 4.26%, respectively, in the IMDS process. Germ recovered from the IMDS process was 0.54% lower than that from the conventional steeping process.  相似文献   
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Twenty growing crossbred calves (mean body wt. 159.7 ± 3.94 kg) were randomly divided into 4 groups 5 in each following randomized block design. To assess the voluntary dry matter intake (VDMI) during preliminary feeding period, all the animals were fed concentrate mixture and wheat straw ad libitum. The lowest DMI amongst all animals fed ad libitum was defined as ‘VDMI’. The animals were fed at four fixed levels. The highest level of DMI was 95% of VDMI (group 1) as determined in preliminary period of feeding the other 3 levels were 80% (group 2), 60% (group 3) and 40% (group 4) of the VDMI. The experimental feeding was continued for a month followed by a metabolism trial. The dry matter intake through concentrate (crushed maize 33, deoiled-soya meal 32, wheat bran 32, mineral mixture 2 and common salt 1 part) and roughage (wheat straw) was 40:60. The DMI (kg/d) and percent of body weight ranged from 1.62 (group 4) to 4.06 (group 1) and 1.20 to 2.58, respectively. The CP intake (g/d) varied from 177 to 442 among 4 groups. The intake of DM, OM, CP, EE, NDF, ADF and hemi-cellulose (g/d or g/kg w0.75) was also significantly (P < 0.05) different among 4 groups. The digestibility of DM in groups 1, 2, 3 and 4 was 59.9, 61.7, 64.6 and 30.4%, respectively and was significantly (P < 0.05) lower in group 4 as compared to the remaining 3 groups. The digestibility of other all nutrients viz. OM, CP, EE, NDF, ADF and HC was comparable among groups 1, 2 and 3. However, the digestibility of these nutrients was significantly (P < 0.05) lower in group 4 (40% intake) as compared to the other 3 groups. Intake and balance of N was significantly (P < 0.01) different among 4 groups, being the lowest in group 4. Animals of groups 1, 2 and 3 were in positive nitrogen balance, however, animals of group 4 were in negative N balance. The results revealed that nutrient utilization was unaffected up to 60% level but it was drastically reduced at 40% level of feed intake. It was also observed that calves maintained on 80 and 60% of feed intake lost body weight (250–300 g/d).  相似文献   
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The effects of Fasciola gigantica infection on bodyweight gain, dry matter intake, digestibility of nutrients and feed conversion efficiency in buffalo calves were investigated. Nine male buffalo calves of the Murrah breed, aged 12 to 15 months with a mean (se) bodyweight of 166 (12.5) kg, were randomly assigned to groups of five (group 1) and four (group 2). The animals in group 1 were given 1000 viable, mature metacercariae of F gigantica orally, while the animals in group 2 served as uninfected controls. They were stall fed on diets containing a concentrate mixture and ad libitum wheat straw and were maintained by standard management practices for a period of 165 days after infection. The average daily liveweight gain of the infected animals was 110.6 g, compared with 439.4 g in the uninfected controls, and was associated with the appearance and establishment of immature flukes in hepatic bile ducts. The feed conversion efficiency declined significantly (P<0.01) from 41 days after infection and was lowest at the end of the experiment. F gigantica infection did not influence the digestibility of the nutrients. The impaired feed conversion efficiency was mainly due to a reduction in dry matter intake due to inappetence.  相似文献   
8.
Field experiments were conducted at two locations (Clayton and Jackson Springs, NC) to determine the influence of vegetation-free strip width (VFSW) and irrigation on newly planted peach growth and yield in a low-density orchard with a volunteer weedy ground cover. The experiments included VFSW of 0, 0.6, 1.2, 2.4, 3, or 3.6 m under irrigated or nonirrigated conditions. Seasonal variation in the orchard floor vegetation was observed as different weed species reported in summer and winter. However, this difference was not apparent with respect to VFSF and irrigation. At Jackson Springs, NC, the predicted irrigated VFSW which would produce the same trunk cross-sectional area (TCSA) as the grower standard (3-m nonirrigated) was 1.5, 1.3, and 0.8 m for one-, two-, and three-year-old trees, respectively. The predicted irrigated VFSW which would produce the same yield as the grower standard was 1.16 m. At Clayton, TCSA and fruit yield were not different by irrigation, but did increase linearly with VFSW. At both locations, leaf nitrogen (N) concentration was lower in irrigated trees than nonirrigated trees. Leaf N, leaf area, and SPAD were positively related to VFSW at Jackson Springs. In contrast, leaf N concentration was not different by VFSW at Clayton. However, leaf area and SPAD were positively related to VFSW at Clayton. These results suggest that a 1.5 m VFSW combined with proper irrigation and fertilization will produce tree growth and yield in newly planted orchard with volunteer weedy vegetation similar to the current grower standard in the southeastern USA.  相似文献   
9.
Pilot-scale dry-milling runs were conducted to study the feasibility of using a short-duration single-stage tempering procedure for the tempering-degerminating system, instead of the 17.8–21.5 hr of conventional three-stage tempering procedures reported in the scientific literature. Using a Beall degerminator No. 0, pilot-scale dry-milling experiments were conducted at 10 tempering levels: 0, 5, 10, 15, 30, 45, 60, 120, 180, and 240 min. Variation in moisture content of through- and tail-stock fractions, degerminator throughput, ratio of tail- to through-stock, yields of different sized grits from tail- and through-stock fractions, and the recovery of germ and pericarp were used to compare tempering periods. A decrease in the milling action was observed for tempering durations >30 min. A tempering period of 15 min gave the highest grit recovery and a 30-min tempering period resulted in the highest germ and pericarp recovery. Based on these results, it was concluded that short tempering periods of 10–30 min as compared to 17.8–21.5 hr could be used for the tempering-degerminator system.  相似文献   
10.
Summary The causative sources of common variation of seven components of fodder yield in oats were analysed, using the centroid method of factor analysis. Two factors together accounted for most of the inter-correlations of these characters. Factor 1 had different degrees of positive loading on all characters, the highest being on the fodder yield. Factor 2 affected negatively a few and positively the remaining characters. The plant height and fodder yield were affected positively by Factor 1 and negatively by Factor 2. Factor 1 and 2 were significantly negatively associated with each other. The fodder yield components in the material studied seem to be influenced by the two interacting hormonal systems. The implications of the findings, in selecting for high quality and high yielding varieties of fodder oats, are discussed.  相似文献   
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