Physiology of flowering and grain filling in faba bean     

J.W. Patrick  F.L. Stoddard 《Field Crops Research》2010

The development of flowers and then that of seeds are key processes in the formation of yield in faba bean (Vicia faba L.), as in other grain legumes. Winter faba bean generally has a quantitative vernalization requirement, allowing flowering to occur at a lower node than in unvernalized plants. Some germplasm is day-neutral, other germplasm is long-day with a critical daylength between 9.5 and 12 h. Progress toward flowering follows a conventional thermal-time model, with 830–1000 °C-d above 0 °C required for the onset of flowering and an optimum temperature of 22–23 °C. Flowers may abscise from the crop because of lack of pollination, because proximal flowers on the same raceme are fertilized, because of vegetative–reproductive competition for assimilate, or because of stresses such as drought.  相似文献   

Stimulation of Ovulation in Seasonally Anovulatory and Vernal Transitional Mares with Estradiol and Domperidone: Dose and Combination Studies     

Pamela B. Mitcham  Donald L. Thompson Jr.  Tad T. Thompson  Scott D. Bennett  Patrick J. Burns  Thomas J. Caltabilota 《Journal of Equine Veterinary Science》2010

Three experiments were conducted to test the efficacy of different doses of estradiol cypionate (ECP) and domperidone for inducing ovulation in seasonally anovulatory (January; Experiments 1 and 2) and transitional period (March; Experiment 3) mares. In the first two experiments, mares in Kentucky and Louisiana were administered domperidone (3 g in biodegradable particles) alone or after pretreatment with 100 or 150 mg of ECP; another group received ECP, domperidone, and progesterone, and a fifth group received ECP and progesterone only (the latter two in Kentucky). Control mares in both states received no treatment. The proportion of mares ovulating within 35 days (for mares treated in January) was greater (P = .0002) for those receiving any combination of ECP plus domperidone relative to mares not receiving the combined treatment. Addition of progesterone to ECP plus domperidone did not enhance (P = .7) the response relative to the combination alone; domperidone by itself, or ECP plus progesterone, did not alter the response relative to controls (P > .24). Experiment 3 was conducted in Louisiana as a 2 × 3 factorial, with two doses of domperidone (1.5 or 3 g) and three doses of ECP (0, 75, or 150 mg). There was no main effect of domperidone or ECP dose; a greater proportion (P = .055) of mares receiving any combination of ECP plus domperidone ovulated in 21 days compared with those receiving no ECP. In conclusion, pretreatment with ECP before injection of domperidone 10 days later can be used to increase the proportion of mares ovulating early in the year; within the limits of the present experiments, there appears to be no difference in doses of ECP of 75, 100, or 150 mg, and no difference in doses of domperidone of 1.5 or 3 g.  相似文献   

Management of the Dorsal Hoof Wall and Its Potential Effects on the Laminitic Hoof     

Patrick T. Reilly 《Journal of Equine Veterinary Science》2010

Appropriate management of the equine hoof during chronic laminitis varies by protocol and practitioner. Sequential removal of the dorsal hoof wall was examined in-vivo on a laminitic horse at the walk, revealing an increase in solar force under the margin of the distal phalanx as measured through the use of an in-shoe force measuring system.  相似文献   

Some Observations on the Materials Used in the Management of Foot Pain     

Patrick T. Reilly 《Journal of Equine Veterinary Science》2010

There are a wide range of polymers available for supporting the equine hoof. A review of the material characteristics of materials used to support the laminitic hoof in the form of sole support, as well as an examination of the thermal effect of exothermal adhesives at the level of sensitive tissue in the foot and the long term effect of a fabric cuffed shoe on the amount of distortion to the dorsal hoofwall at the toe.  相似文献   

Evaluation of Pharmacokinetic-Pharmacodynamic Relationships for BioRelease Meloxicam Formulations in Horses     

Patrick J. Burns  Chris Morrow  Richard M. Gilley  Mark G. Papich 《Journal of Equine Veterinary Science》2010

  相似文献   

Porcine circovirus type 2 (PCV2)-infection and re-inoculation with homologous or heterologous strains: virological, serological, pathological and clinical effects in growing pigs     

Tanja Opriessnig  John R. Prickett  Darin M. Madson  Hui-Gang Shen  Nicole M. Juhan  Roman M. Pogranichniy  Xiang-Jin Meng    Patrick G. Halbur 《Veterinary research》2010,41(3)

Long-term PCV2 infection and/or concurrent infection with genotypes PCV2a and PCV2b may play a role in the development of clinical porcine circovirus-associated disease (PCVAD). To evaluate this premise, 24 11-week-old specific pathogen-free (SPF) pigs were randomly assigned to 1 of 4 treatments: negative controls, a single inoculation with PCV2a, single inoculation followed by re-inoculation with a homologous PCV2a strain, or repeated inoculations with heterologous strains (PCV2a, PCV2b). Pigs were evaluated for clinical signs daily through 140 days post inoculation (dpi). Serum samples were collected every other day from dpi 0 through 14 and weekly thereafter. PCV2-inoculated pigs were viremic by dpi 2 and 13 of 18 pigs remained viremic at 140 dpi. No statistical differences in the onset, level, or duration of PCV2 viremia were detected among treatment groups. Anti-PCV2 antibodies were detected between 14 and 28 dpi and were present through 140 dpi without statistical differences in antibody response among treatment groups. In the current study, pigs had extended viremia combined with detectable tissue PCV2 antigen levels despite the presence of high levels of anti-PCV2 antibody; however, no clinical disease was observed.  相似文献   

The evolution of maximum body size of terrestrial mammals     

Smith FA  Boyer AG  Brown JH  Costa DP  Dayan T  Ernest SK  Evans AR  Fortelius M  Gittleman JL  Hamilton MJ  Harding LE  Lintulaakso K  Lyons SK  McCain C  Okie JG  Saarinen JJ  Sibly RM  Stephens PR  Theodor J  Uhen MD 《Science (New York, N.Y.)》2010,330(6008):1216-1219

The extinction of dinosaurs at the Cretaceous/Paleogene (K/Pg) boundary was the seminal event that opened the door for the subsequent diversification of terrestrial mammals. Our compilation of maximum body size at the ordinal level by sub-epoch shows a near-exponential increase after the K/Pg. On each continent, the maximum size of mammals leveled off after 40 million years ago and thereafter remained approximately constant. There was remarkable congruence in the rate, trajectory, and upper limit across continents, orders, and trophic guilds, despite differences in geological and climatic history, turnover of lineages, and ecological variation. Our analysis suggests that although the primary driver for the evolution of giant mammals was diversification to fill ecological niches, environmental temperature and land area may have ultimately constrained the maximum size achieved.  相似文献   

Ecohydrological energy inputs in semiarid coniferous gradients: Responses to management- and drought-induced tree reductions     

Patrick D. Royer  David D. Breshears  Chris B. Zou  Neil S. Cobb  Shirley A. Kurc 《Forest Ecology and Management》2010

  相似文献   

Long-term effects of single prescribed fires on hardwood regeneration in oak shelterwood stands     

Patrick H. Brose 《Forest Ecology and Management》2010

One of the arguments against using prescribed fire to regenerate oak (Quercus spp.) forests is that the improvement in species composition of the hardwood regeneration pool is temporary and multiple burns are necessary to achieve and maintain oak dominance. To explore this concern, I re-inventoried a prescribed fire study conducted in the mid-1990s to determine the longevity of the effects of a single prescribed fire on hardwood regeneration. The initial study was conducted in three oak shelterwood stands in central Virginia, USA. In 1994, each stand was divided into four treatments (spring, summer, and winter burns and a control) and the hardwood regeneration was inventoried before the fires. During the burns, fire intensity was measured and categorized in each regeneration sampling plot. Second-year postfire data showed marked differences in species mortality rates, depending on season-of-burn and fire intensity: oak and hickory (Carya spp.) regeneration dominated areas burned by medium- to high-intensity fire during the spring and summer while yellow-poplar (Liriodendron tulipifera) and red maple (Acer rubrum) seedlings dominated unburned areas and all areas treated with low-intensity fire regardless of season-of-burn. The treatments were re-inventoried in 2006 and 2007 to determine whether these fire effects were still present. The new data show that the species distributions by season-of-burn and fire intensity found in 1996 still existed 11 years after the treatments. The fact that fire effects in oak shelterwood stands can last at least a decade has important management implications for resource professionals interested in sustaining oak forests in the eastern United States.  相似文献   

Regeneration niche of the Canarian juniper: the role of adults,shrubs and environmental conditions     

Rüdiger Otto  Bertil O. Krüsi  Juan D. Delgado  José María Fernández-Palacios  Eduardo García-Del-Rey  José Ramón Arévalo 《Annals of Forest Science》2010,67(7):709-709

–	• Canarian Juniper woodlands, now very scarce, are rich in endemic and endangered plants. However, many aspects of juniper regeneration are almost unknown.  相似文献    [首页] « 上一页 [95] [96] [97] [98] [99] 100 下一页 » 末  页»