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101.
102.
Summary

In a trial of Romanesco cauliflower inbred lines, hybrids and controls, differences between mean performance of hybrids and their mid-parents demonstrated heterosis, with F1 hybrids producing larger curds on larger plants with earlier maturity in most crosses. In F1 hybrids, the small increases in curd depth, together with reduction in looseness and the overall slight improvement in curd quality, were attributed to the ability to harvest hybrid curds at earlier maturity than their inbred parents. The ability to increase the marketable yield is a prime benefit of F1 hybrids in Romanesco cauliflowers. An effect of early test crossing was to improve seed production, both in inbred lines and hybrids. With a wider diversity of inbred lines, early testing generally would be advantageous and would also provide an opportunity to screen for inbred lines with strong self incompatibility as potential F1 parents.  相似文献   
103.
Summary

Carrot roots from a range of environments, developmental stages and cultivars showed variation in splitting susceptibility from 3.8% to 72.5%. Estimates of tissue tensile strength, fracture toughness and residual strain for roots from these sources were not related to estimates for damage. The measurement of release of intrinsic stress from whole-root sections showed some relationship with damage in that the most susceptible cultivars also displayed greater release of stress. These same varieties had larger storage cells in their outer parenchyma. Developmental variation in tissue strength induced by different sowing dates and years was inconsistent between years. Increases in strength of root tissue with advancing date during the autumn observed in field experiments, were not related to temperature changes imposed in controlled environment. Variation in water and solute potentials was generally greater than variation in turgor potential, which remained well conserved in all experiments. Fracture toughness, which is dependent on tissue water status, was not well related to turgor in these experiments.  相似文献   
104.
Summary Seed of differing maturity dates of cv.Arran Pilot andMajestic were produced by planting sprouted and unsprouted mother tubers and by either destroying the foliage 2–3 weeks before senescence or allowing natural maturity to take place. Seed from crops of earlier natural maturity sprouted earlier and inArran Pilot grew faster if sprouting was encouraged soon after harvest. Other small differences in sprout growth were recorded, but none of the treatments applied to the first generation crop affected the time of emergence, stem number, growth of foliage or tubers in the second generation crop.
Zusammenfassung An der Edinburgh School of Agriculture Farms wurden zwei Versuche w?hrend je zwei Jahren (1963–65 und 1964–66) durchgeführt, um die Einflüsse des Vorkeimens und der Krautvernichtung bei der 1. Generation Pflanzgut (Mutterknollen) auf das Keimwachstum, Pflanzenwachstum und den Ertrag im Nachbau (2. Pflanzgutgeneration) zu untersuchen. Beide Versuche umfassten die SortenArran Pilot undMajestic. Einzelheiten der Verfahren sind in Tabelle 1 angegeben. Durch das Vorkeimen des für die Pflanzguterzeugung benützten Saatgutes (1. Pflanzgutgeneration) wurde das Reifedatum im Vergleich zu dem nicht vorgekeimten Saatgut beiArran Pilot um 5–16 Tage, beiMajestic um 10–20 Tage vorverlegt (Abschnitt Material und Methoden). In Versuch II (Abbrennen des Krautes 2–3 Wochen vor der natürlichen Reife) wies das geerntete Pflanzgut beider Sorten einen um 2–3% niedrigeren Trockensubstanzgehalt auf als bei natürlicher Reife (Tabelle 3). Pflanzgut, erzeugt von vorgekeimten (N1, Nc1 und M1) Mutterknollen (sog. 1. Pflanzgutgeneration) zeigte in Versuch I, nicht aber in Versuch II, ein früheres Auskeimen (Tabelle 4) als Pflanzgut von nicht vorgekeimten (O1) Mutterknollen. Die Einflüsse der Vorkeim-Behandlungen auf die Keimzahl, Keiml?nge und die Entwicklung waren unterschiedlich, aber in Versuch II bildeten Saatknollen vonArran Pilot der früh vorgekeimten (N1) Mutterknollen l?ngere Keime als jene von sp?t vorgekeimten (M1) oder nicht vorgekeimten (O1) Best?nden (Tabelle 5). Saatgut von abgebrannten Best?nden (B.D.) vonArran Pilot, nicht jedoch vonMajestic, brachte kürzere Keime als Saatgut von natürlich ausgereiften Best?nden (MAT). Es zeigte sich kein Einfluss irgendeiner bei den Mutterknollen angewendeten Vorkeim- oder Krautvernichtungsbehandlungen auf die Anzahl der Stengel (Tabelle 7), das Pflanzenwachstum oder auf die Ertr?ge (Tabelle 8) des Nachbaues (2. Pflanzgutgeneration). Es kann daraus geschlossen werden, dass in Nordwest-Europa die Unterschiede in den Reifezeiten, die durch das Vorkeimen der Mutterknollen oder durch das frühe Abbrennen des Krautes hervorgerufen werden, ohne bedeutenden Einfluss auf die Leistungen des erzeugten Nachbaues bei der Pflanz- oder Speisekartoffelerzeugung bleiben.

Résumé Deux expériences, s'étendant chacune sur deux années (1963–65 et 1964–66) et portant chacune sur les variétésArran Pilot etMajestic, ont été réalisées à la ferme de l'Ecole d'Agriculture d'Edimbourg pour déterminer les effets de la prégermination et de la destruction du feuillage effectuées sur une première génération d'une culture de plants, sur le développement des germes, le développement de la culture et la production de la seconde génération. On trouvera les traitements détaillés dans le tableau 1. La prégermination de la première génération avance la date de maturité, de 5–16 jours chezArran Pilot et de 10–20 jours chezMajestic, par rapport aux plants non germés (Matérials et méthodes). Dans l'expérience II, la destruction complète du feuillage 2–3 semaines avant la maturité naturelle diminue la teneur en matière sèche des plants de 2–3% par rapport à la maturité naturelle, et cela chez les deux variétés (tableau 3). Dans l'expérience I mais non dans l'expérience II, les plants issus de la récolte d'une première génération prégermée (N, Nc1 et M1) germent plus t?t (tableau 4) que les plants récoltés non prégermés (O1). Les effets des traitements de prégermination sur le nombre, la longueur des germes et sur le développement sont variables mais dans l'expérience II les plants d'Arran Pilot issus de la première génération germée précocement (N1) produisent des germes plus longs que ceux issus de cultures germées tardivement (M1) ou non prégermées (O1) (tableau 5). ChezArran Pilot mais non chezMajestic, les plants issus de cultures défanées (B.D.) donnent des germes plus courts que les plants provenant de cultures qui ont pu atteindre leur maturité naturelle (MAT). Il n'appara?t aucun effet, ni de la prégermination, ni de la destruction du feuillage appliqué à la première génération de production de plants, sur le nombre de tiges (tableau 7), le développement de la culture ou la production (tableau 8) en seconde génération. Il est conclu que, dans le Nord-Ouest de l'Europe, la variation des dates de maturité causée par la prégermination du plant-mère ou la destruction prématurée des fanes n'a guère d'influence sur les productions de plants ou de pommes de terre de consommation dans la génération suivante.


Edinburgh School of Agriculture Miscellaneous Publication No. 501.  相似文献   
105.
ABSTRACT: Blood samples were obtained from 38 wild red deer (Cervus elaphus) at two sites in Ireland and subjected to PCR analysis of the 18S rRNA gene followed by sequencing. Two fragments of the 18S rRNA gene were generated by two different PCR protocols and subsequent sequencing suggested that at least six of the deer were infected by a babesia that, in those loci, is indistinguishable from Babesia divergens, an important tick-borne pathogen of cattle and of zoonotic significance. Additionally, a B. odocoilei-like parasite was detected in three samples and a babesia that did not match any sequences in the GenBank database was found in five samples. Neither B. capreoli nor B. venatorum (EU1) were found. There have been several reports of B. divergens occurring in deer species, including red deer, roe deer (Capreolus capreolus) and reindeer (Rangifer tarandus). However, in view of recent re-sequencing of bovine-origin samples deposited previously in GenBank, it is unlikely that any of these sequences from deer are B. divergens. The present study describes the only deer piroplasm detected so far that shows complete identity with B. divergens, in just over half of the 18S rRNA gene. The entire gene of this deer parasite should be analysed and transmission experiments undertaken before the infectivity of B. divergens for red deer can be confirmed.  相似文献   
106.
107.
A survey was conducted to quantify incidence of Beef Quality Assurance (BQA)-related defects in market beef and dairy cows and bulls selling at auction during 2 seasons in 2008. Twenty-three BQA-related traits were evaluated by 9 trained personnel during sales at 10 livestock auction markets in Idaho (n = 5; beef and dairy), California, (n = 4; dairy only), and Utah (n = 1; beef and dairy). Overall, 18,949 unique lots (8,213 beef cows, 1,036 beef bulls, 9,177 dairy cows, and 523 dairy bulls,) consisting of 23,479 animals (9,299 beef cows, 1,091 beef bulls, 12,429 dairy cows, and 660 dairy bulls) were evaluated during 125 sales (64 spring, 61 fall) for dairy and 79 sales (40 spring, 39 fall) for beef. The majority of market beef cows and bulls (60.9 and 71.3%, respectively) were predominantly black-hided, and the Holstein hide pattern was observed in 95.4 and 93.6% of market dairy cows and bulls, respectively. Market cattle weighed 548 ± 103.6 kg (beef cows), 751 ± 176.1 kg (beef bulls), 658 ± 129.7 kg (dairy cows), and 731 ± 150.8 kg (dairy bulls). Most beef cows (79.6%) weighed 455 to 726 kg, and most beef bulls (73.8%) weighed 545 to 954 kg, respectively. Among market beef cattle, 16.0% of cows and 14.5% of bulls weighed less than 455 and 545 kg, respectively, and 63.7% of dairy cows and 81.5% of dairy bulls weighed 545 to 817 kg or 545 to 954 kg, respectively. However, 19.5% of dairy cows and 13.1% of dairy bulls weighed less than 545 kg. Mean BCS for beef cattle (9-point scale) was 4.7 ± 1.2 (cows) and 5.3 ± 0.9 (bulls), and for dairy cattle (5-point scale) was 2.6 ± 0.8 (cows) and 2.9 ± 0.6 (bulls). Some 16.5% of beef cows and 4.1% of beef bulls had a BCS of 1 to 3, whereas 34.8% of dairy cows and 10.4% of dairy bulls had a BCS of 2 or less. Emaciation (beef BCS = 1, dairy BCS = 1.0) or near-emaciation (beef BCS = 2, dairy BCS = 1.5) was observed in 13.3% of dairy cows and 3.9% of beef cows. Among beef cattle, 15.1% of cows and 15.4% of bulls were considered lame. In contrast, 44.7% of dairy cows and 26.1% of dairy bulls were lame. Ocular neoplasia (cancer eye) was observed in only 0.6% of beef cows, 0.3% of beef bulls, 0.3% of dairy cows, and 0.0% of dairy bulls. However, among animals with ocular neoplasia, it was cancerous in 34.4% of beef bulls, 48.0% of dairy cows, and 73.3% of beef cows. In conclusion, numerous quality defects are present in market beef and dairy cattle selling at auction in the Western United States, which could influence their value at auction.  相似文献   
108.
Relative effects of Beef Quality Assurance (BQA)-related defects in market beef and dairy cows and bulls on selling price at auction was evaluated during 2008. The presence and severity of 23 BQA-related traits were determined during sales in Idaho, California, and Utah. Overall, 18,949 unique lots consisting of 23,479 animals were assessed during 125 dairy sales and 79 beef sales. Mean sale price ± SD (per 45.5 kg) for market beef cows, beef bulls, dairy cows, and dairy bulls was $45.15 ± 9.42, $56.30 ± 9.21, $42.23 ± 12.26, and $55.10 ± 9.07, respectively. When combined, all recorded traits explained 36% of the variation in selling price in beef cows, 35% in beef bulls, 61% in dairy cows, and 56% in dairy bulls. Premiums and discounts were determined in comparison with a "par" or "base" animal. Compared with a base BCS 5 beef cow (on a 9-point beef scale), BCS 1 to 4 cows were discounted (P < 0.0001), whereas premiums (P < 0.05) were estimated for BCS 6 to 8. Compared with a base BCS 3.0 dairy cow (on a 5-point dairy scale), more body condition resulted in a premium (P ≤ 0.001), whereas a less-than-desirable BCS of 2.0 or 2.5 was discounted (P < 0.0001). Emaciated or near-emaciated cows (beef BCS 1 or 2; dairy BCS 1.0 or 1.5) were discounted (P < 0.0001). Compared with base cows weighing 545 to 635 kg, lighter BW beef cows were discounted (P < 0.0001), whereas heavier beef cows received (P < 0.05) a premium. Compared with a base dairy cow weighing 636 to 727 kg, lighter BW cows were discounted (P < 0.0001), whereas heavier cows (727 to 909 kg) received a premium (P < 0.01). Beef and dairy cows with any evidence of lameness were discounted (P < 0.0001). Presence of ocular neoplasia in the precancerous stage discounted (P = 0.05) beef cows and discounted (P < 0.01) dairy cows, whereas at the cancerous stage, it discounted (P < 0.0001) all cows. Hide color influenced (P < 0.0001) selling price in beef cattle but had no effect (P = 0.17) in dairy cows. Animals that were visibly sick were discounted (P < 0.0001). Results suggest that improving BCS and BW, which producers can do at the farm or ranch level, positively affects sale price. Furthermore, animals that are visibly sick or have a defect associated with a possible antibiotic risk will be discounted. Ultimately, animals with minor quality defects should be sold in a timely manner before the defect advances and the discount increases.  相似文献   
109.
110.
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