A survey of yield differences between transgenic and non-transgenic crops     

PM Guerin  TF Guerin 《Archives of Agronomy and Soil Science》2013,59(3):333-345

In the current survey, there was no clear evidence that GM (genetically modified) crops are higher yielding than those conventionally bred<fnoteref rid="fn1">1</fnoteref>. Furthermore, there were no trials to support valid comparisons of yield per se. This article investigates GM crop yields, introducing the importance of hybrid vigour and a non-stress environment for higher percentage heritability selection and therefore more productive conventional plant breeding and improved crops. GM technology and crops are compared with proven plant breeding methods, with respect to hybrid vigour and the economic viability of both systems. These proven methods of plant breeding are (1) traditional landrace cropping, (2) conventional Mendelian breeding and (3) Isolection Mendelian breeding, and are also considered historically.  相似文献   

The effects of fungicidal spraying on leaf spotting and yield of tulips infected with Botrytis tulipae (Lib.) Lind., the cause of tulip fire     

D. Price  D.Turquand Elizabeth  L.W. Wallis 《The Journal of Horticultural Science and Biotechnology》2013,88(1):63-70

From 1966 to 1969 several fungicides sprayed at different frequencies and in some cases at different rates were used in experiments to control the foliar phase of tulip fire, caused by Botrytis tulipae. Dithiocarbamate and dichlofluanid formulations were the most effective when measured either by the reduction in amounts of leaf spotting or increase in bulb yield, two properties which were shown to be inversely related. Although no significant increases in yield could be attributed to either frequency, formulation or rate of application, two-week intervals between spraying reduced leaf spotting in both 1968 and 1969.  相似文献   

Grapevine phenolic compounds in xylem sap and tissues are significantly altered during infection by Xylella fastidiosa     

Wallis CM  Chen J 《Phytopathology》2012,102(9):816-826

Pierce's disease of grapevine (PD), caused by the bacterial pathogen Xylella fastidiosa, remains a serious problem for grape production in California and elsewhere. This research examined induction of phenolic compounds in grapevines ('Thompson Seedless') infected with X. fastidiosa over a 6-month period. Two months postinoculation with X. fastidiosa, catechin, digalloylquinic acid, and astringin were found at greater levels in xylem sap; multiple catechins, procyanidins, and stilbenoids were found at greater levels in xylem tissues; and precursors to lignin and condensed tannins were found at greater levels in xylem cell walls. However, such large-scale inductions of phenolic compounds were not observed 4 months after inoculation. Six months after inoculation, infected plants had significantly reduced phenolic levels in xylem sap and tissues when compared with control plants, including lowered levels of lignin and condensed tannins. At 6 months, PD symptoms were severe in infected plants and most photosynthetic tissue was abscised. These results suggest that, even though grapevine hosts may initially respond to X. fastidiosa infections with increased production of phenolic compounds, ultimately, PD causes grapevines to enter a state of decline whereby diseased hosts no longer have the resources to support secondary metabolite production, including defense-associated phenolic compounds.  相似文献   

Relationships between vaccine and virulent strains of Babesia bovis during co-infection in calves     

WK JORGENSEN  PJ JESTON  PM BOWLES  J. CROFT  AE LEW  JB MOLLOY  RJ DALGLIESH 《Australian veterinary journal》1998,76(1):57-58

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Comparison of Intraoperative Behavioral and Hormonal Responses to Noxious Stimuli between Mares Sedated with Caudal Epidural Detomidine Hydrochloride or a Continuous Intravenous Infusion of Detomidine Hydrochloride for Standing Laparoscopic Ovariectomy     

Joanna Virgin  Dean Hendrickson  Ty Wallis  Sangeeta Rao 《Veterinary surgery : VS》2010,39(6):754-760

Objective: To compare the presence or absence of pain, pain‐related behavioral responses, and hormonal responses to noxious stimuli during standing laparoscopic ovariectomy in mares sedated with continuous intravenous (IV) detomidine infusion and caudal epidural detomidine. Study Design: A double blind prospective study. Animals: Mares (n=12) Methods: Mares were divided into 2 treatment groups; 6 were sedated using continuous IV detomidine infusion and 6 were sedated with caudal epidural detomidine. All mares received IV xylazine (0.33 mg/kg) and butorphanol tartrate (5 mg) premedication before detomidine administration. Venous blood samples were taken to assess serum cortisol levels in each mare at 4 time points: a baseline cortisol measurement after the mares' arrival to the clinic, 10 minutes before surgery, at the removal of the 2nd ovary, and 10 minutes postsurgery. Two surgeons performed bilateral ovariectomy and at 8 time points involving surgical manipulations, noted the presence or absence of pain (yes/no) and scored the patient's response on a 10 cm visual analogue scale (VAS) for pain assessment with 0 indicating no pain responses and 10 cm indicating pain so severe that the mare required additional sedation or analgesia to complete the procedure. Each mare was also assigned a VAS score by each surgeon for the overall satisfaction of analgesia during the entire procedure. Results: Serum cortisol levels between the 2 detomidine administration groups differed significantly at the baseline (precortisol) measurement but not at the 3 remaining time points. Seven of the procedures within the surgeries did not differ significantly in VAS scores between the 2 groups. The initial grasp of the left ovary (the 1st ovary) in the continuous infusion group had a significantly higher (P=.05) median VAS score compared with the caudal epidural group. Conclusions: Mares sedated with a continuous IV infusion of detomidine have similar hormonal and behavioral responses to painful stimuli during standing laparoscopic ovariectomy as mares sedated with caudal epidural detomidine. Clinical Relevance: Sedation using a continuous IV infusion of detomidine can be used for laparoscopic ovariectomy in mares.  相似文献   

Foliar chemistry of juvenile Eucalyptus grandis clones does not predict chemical defence in maturing ramets     

Ian R. Wallis  Helen J. Smith  Martin L. Henery  Michael Henson  William J. Foley 《Forest Ecology and Management》2010

The tendency for managers of eucalypt plantations to plant large, homogeneous (i.e. clonal) stands presents a new suite of problems. Perhaps foremost among them is the elevated risk of disease or predation. One way to counter this risk is to select material with high natal resistance, such as material with high concentrations of plant secondary metabolites. This would be much simpler if we could predict future defences from the chemistry of juvenile plants. The present study aimed to determine the relationship between the concentrations of formylated phloroglucinol compounds (FPCs) in the leaves of newly established Eucalyptus grandis (Hill ex Maiden) clones in the nursery and those in the same genetic material in experimental plantations. There was almost no relationship between the concentrations of defensive chemicals in the leaves of newly established E. grandis clones growing in pots in the nursery and of those in the same genetic material growing in plantations. This implies that age effects and probable gene × environment interactions prevent evaluating the defensive qualities of clones until they are several years old and even then the results are site-specific.  相似文献   

Use of enrofloxacin in laying birds     

A S Wallis 《The Veterinary record》1991,128(23):554-555

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Poultry: principles of disease control. 3. Vaccination     

A S Wallis 《The Veterinary record》1970,86(15):425-428

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Current techniques in rapid bluetongue virus diagnosis     

AR GOULD  AD HYATT  BT EATON  JR WHITE  PT HOOPER  SD BLACKSELL  PM Le BLANC SMITH 《Australian veterinary journal》1989,66(12):450-454

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Assessing the usefulness of B‐mode and colour Doppler sonography,and measurements of circulating progesterone concentrations for determining ovarian responses in superovulated ewes          下载免费PDF全文

MEF Oliveira  IF Ribeiro  MGK Rodriguez  GS Maciel  JF Fonseca  FZ Brandão  PM Bartlewski 《Reproduction in domestic animals》2018,53(3):742-750

The main goal of this study was to assess the usefulness of two imaging modalities, namely the B‐mode and colour Doppler sonography, and serum progesterone (P₄) concentrations for determining the ovarian response in superovulated ewes. Twenty‐four sexually mature Santa Inês ewes underwent the superovulatory treatment consisting of eight injections of porcine FSH (total dose of 200 or 133 or 100 mg; n  =  8 ewes/total dose) given at 12‐hr intervals and initiated 48 hr before CIDR ^® (Pfizer Inc., Auckland, New Zealand) removal. Six days after natural mating, the ovaries of all donor ewes were visualized and examined with transrectal ultrasonography and then with videolaparoscopy to identify and enumerate corpora lutea (CL ) and luteinized unovulated follicles (LUF s). Jugular blood samples were collected just prior to ovarian examinations. The total number of CL (r  =  .78 and 0.83, p  <  .0001) and LUF s (r  =  .74 and 0.90, p  <  .0001) enumerated using the B‐mode and colour Doppler ultrasonographic technique, respectively, were correlated with that ascertained by videolaparoscopy. Circulating concentrations of P₄ were related directly to the number of healthy CL (r  =  .73, p  =  .0002) and inversely to the number of prematurely regressing CL (r  = ?.46, p  =  .03), but the accuracy of predicting the number of short‐lived CL with serum P₄ concentrations was very poor. The present results indicate that ultrasonographic imaging and serum P₄ measurements on the day of embryo recovery are useful indicators of total/normal CL numbers and both ultrasonographic techniques can be used to quantify LUF s in superovulated ewes.  相似文献