Effects of Bermudagrass hay and soybean hulls inclusion on performance of sheep fed cactus-based diets     

Santos  A. O. A.  Batista  Ângela M. V.  Mustafa  Arif  Amorim  G. L.  Guim  A.  Moraes  A. C.  de Lucena  R. B.  de Andrade  R. 《Tropical animal health and production》2010,42(3):487-494

The objective of this experiment was to determine the effects of replacing corn with soybean hulls (SH) or Bermudagrass tifton hay (TH) on performance of sheep fed cactus-based diets. Three ruminally fistulated sheep were used in a 3 × 3 Latin square experiment with 21-day periods. All diets contained 75% spineless cactus (dry matter basis, DM) and formulated to be isonitrogenous. Fiber source had no influence on nutrient intakes except for the intake of neutral detergent fiber (NDF) which was lower (p < 0.05) for animals fed corn relative to those fed SH or TH. Time expended in rumination and total chewing time were higher (p < 0.05) for animals fed TH than those fed SH or corn. In vivo nutrient digestibilities were similar for all dietary treatments and averaged 69.6%, 74.8%, 69.9%, and 61.8% for DM, organic matter, crude protein, and NDF, respectively. Feeding SH relative to TH and corn decreased ruminal pH (p < 0.05) and increased concentration of total volatile fatty acids (p < 0.05). However, ruminal NH₃–N concentration was higher (p < 0.05) for animal fed TH than for those fed SH or corn. Abdominal distension and ruminal biofilm production were greater (p < 0.05) in animals fed corn or SH than in those fed TH. It was concluded that replacing corn with SH or TH up to 15% of the diet DM in a cactus-based diet had no effect on nutrient intakes or total tract nutrient utilization. Changes in ruminal fermentation parameters reflected differences in ruminal degradability between the two fiber sources. Bermudagrass tifton hay was more effective than SH in reducing the risk of bloat associated with feeding high levels of spineless cactus to ruminants.  相似文献   

Improved efficiency of detection of potato mop-top furovirus in potato tubers and in the roots and leaves of soil-bait plants     

Mohammed Arif  Lesley Torrance  Brian Reavy 《Potato Research》1994,37(4):373-381

Summary A reverse trancription-polymerase chain reaction (RT-PCR) assay was devised and shown to be sensitive and reliable for the detection of potato mop-top virus (PMTV) RNA sequences in the flesh of virus infected potato tubers, and in the roots and leaves of soil-bait plants. This assay was compared with an enzyme-linked immunosorbent assay incorporating PMTV specific monoclonal antibodies (TAS-ELISA). The tests were devised to improve the efficiency of detection of viruliferousSpongospora subterranea in agricultural soils, and PMTV in potato tubers. RT-PCR detected PMTV RNA sequences in the roots and leaves of bait plants after three weeks growth in viruliferous soil, three weeks before the bait plants themselves developed symptoms, and two weeks before the virus was detected by TAS-ELISA. Both RT-PCR and TAS-ELISA detected PMTV in the tubers of primary-infected potatoes. RT-PCR and TAS-ELISA were shown to be more sensitive and reliable than conventional baittests and sap inoculation methods for the detection and diagnosis of PMTV.  相似文献   

Penetration of urea–formaldehyde resins with different formaldehyde/urea mole ratios into softwood tissues     

Arif Nuryawan  Byung-Dae Park  Adya P. Singh 《Wood Science and Technology》2014,48(5):889-902

In order to understand the impact of formaldehyde/urea (F/U) mole ratio on penetration characteristics of urea–formaldehyde (UF) resin into softwood tissues, a quantitative measurement of UF resin penetration into radiata pine (Pinus radiata) tissues from the bond-line was undertaken. Four different F/U mole ratios (1.6, 1.4, 1.2, and 1.0) of UF resins with different viscosities and two levels of hardener (NH₄Cl) for two extreme F/U mole ratios (1.6 and 1.0) were studied. Firstly, field emission scanning electron microscope and confocal laser scanning microscopy were used to localize UF resins in the bond-line for the qualitative evaluation of resin penetration. Then light microscopy was employed to quantitatively measure the resin penetration and bond-line thickness. A decrease in the F/U mole ratio of UF resin that proportionately decreased the resin viscosity resulted in an increase in the average resin penetration and a decrease in the bond-line thickness. Higher hardener level provided a greater resin penetration with all F/U mole ratio UF resins. These results demonstrated that F/U mole ratio had an impact on the penetration and bond-line thickness of UF resins, owing to differences in the reactivity of resins, with higher F/U mole ratio resins being more reactive.  相似文献   

Influence of plant residue chemistry on soil CO2–C production: A study with Arabidopsis thaliana cell wall mutants of KNAT7, MYB75 and CCR1     

Shamim Gul  Joann K. Whalen  Brian E. Ellis  Arif F. Mustafa 《Pedobiologia》2012,55(6):349-356

Alteration of plant lignin concentration is expected to affect the C mineralization of crop residues. Mutations of single genes involved in biosynthesis of secondary cell walls such as KNOTTED ARABIDOPSIS THALIANA 7 (KNAT7), PRODUCTION OF ANTHOCYANIN PIGMENT 1 (PAP1) also known as MYB75, and cinnamoyl CoA reductase 1 (CCR1) coding genes could change lignin concentration in specific plant tissues. This study assessed the CO₂–C production of soil amended with stem and root tissues of down-regulated (k/o) and over expression (o/x) KNAT7 and MYB75 and the CCR1 k/o mutant lines of A. thaliana. KNAT7 k/o and MYB75 k/o were grown in two different environmental conditions (two cohorts) in the greenhouse. Oven dried, finely ground (<0.5 mm) stem and root residues underwent biochemical analysis, then were mixed separately with sandy loam or clay loam soil to assess CO₂–C production under controlled laboratory conditions for 63 days. Compared to wild ecotypes, C:N ratio and acid unhydrolyzable fraction (AUF) concentration tended to be higher in stem residues of KNAT7 k/o and MYB75 k/o mutant lines. The C:N ratio was lower in stem and roots of CCR1 k/o line, and the AUF concentration was lower in CCR1 k/o stem residues than in the wild ecotypes. Hemicelluloses were lower in stem residues of KNAT7 k/o and MYB75 k/o (first cohort) than their wild ecotypes. Cumulative CO₂–C production was lower in soil amended with stem residues of KNAT7 k/o (first cohort) and MYB75 k/o (first and second cohorts). CCR1 k/o stem tissues caused higher CO₂–C production from soil. After 63 days incubation, the acid/aldehyde ratio (Ad/Al) of vanillin (V) and syringyl (S) lignin monomers of soil was higher for stem amended CCR1 k/o and lower for stem amended MYB75 k/o soils as compared to their wild ecotypes. Generally root residues caused lower CO₂–C production from soil than stem residues. There was no difference in CO₂–C production for root residues between mutant lines and their wild ecotypes. In conclusion, KNAT7 k/o, MYB75 k/o and CCR1 k/o mutations resulted in altered C:N ratio and resistant compounds (i.e., AUF) especially in stems, and these alterations in residue chemistry influenced CO₂–C production and also lignin degradation in soil.  相似文献   

Co-inoculation integrated with P-enriched compost improved nodulation and growth of Chickpea (Cicer arietinum L.) under irrigated and rainfed farming systems     

Sher Muhammad Shahzad  Azeem Khalid  Muhammad Saleem Arif  Muhammad Riaz  Muhammad Ashraf  Zafar Iqbal  Tahira Yasmeen 《Biology and Fertility of Soils》2014,50(1):1-12

The present study was designed with the objective of improving the nodulation and growth of chickpea (Cicer arietinum L.) by integrating co-inoculation of Rhizobium sp. (Mesorhizobium ciceri) and plant growth promoting rhizobacteria (PGPR) carrying ACC (1-aminocyclopropane-1-carboxylate) deaminase activity with P-enriched compost (PEC) under irrigated and rainfed farming systems. PEC was prepared from fruit and vegetable waste and enriched with single super phosphate. The results demonstrated that co-inoculation significantly (P?<?0.05) increased the number of nodules per plant, nodule dry weight, pods per plant, grain yield, protein content, and total chlorophyll content under irrigated and rainfed conditions compared to inoculation with rhizobium alone. Integrating PEC with co-inoculation showed an additive effect on the nodulation and growth of chickpea under both farming systems. Analysis of leaves showed a significantly (P?<?0.05) higher photosynthetic rate and transpiration rate in comparison with inoculation with Rhizobium. Compared to irrigated farming system, co-inoculation with PEC under rainfed conditions was more beneficial in improving growth and nodulation of chickpea. Post-harvest soil analysis revealed that the integrated use of bioresources and compost enhanced microbial biomass C, available N content, dehydrogenase, and phosphomonoesterase activities.  相似文献