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121.
K. G. Haynes R. W. Goth S. B. Sterrett B. J. Christ D. E. Halseth G. A. Porter M. R. Henninger D. R. Wilson R. E. Webb D. F. Hammond R. Moore F. L. Haynes S. Arrendell M. J. Wannamaker S. L. Sinden 《American Journal of Potato Research》1992,69(8):515-523
Coastal Chip is a medium-late maturing potato chipping variety suitable for production in locations along the east coast of the United States where heat stress reduces internal quality of tubers. It yields as well as the variety Atlantic but is not as susceptible to heat necrosis. The specific gravity of Coastal Chip averages approximately 0.010 less than Atlantic at locations subject to heat stress. In the seed producing areas of Maine it’s specific gravity averages approximately 0.005 less than that of Atlantic. Tubers are round, netted-skinned, and have moderately deep stem and bud ends. Chips from Coastal Chip are slightly lighter in color than those produced by Atlantic. In mid-Atlantic states where heat stress adversely affects chip color Coastal Chip processes into chips for a slightly longer period of time after harvest than does Atlantic. Glycoalkaloid content of Coastal Chip averaged 7.9 mg/100 g fresh tissue. Sunburned (green) tubers of Coastal Chip develop purple streaks that remain following processing. Hills must be properly covered to reduce losses. Coastal Chip is resistant to race A of the golden nematode (Globodera rostochiensis) and potato virus A. It is tolerant to Verticillium wilt, more susceptible to common scab and Rhizoctonia than Atlantic and susceptible to potato virus X. 相似文献
122.
Seedlings ofSolarium demissum P.I. 230579 in the 5-to 10-leaf stage growing under 18-hour days and at 20 to 24°C developed dark, irregular, slightly elongated local lesions 3 to 5 days following inoculation with any one of three strains of potato virus Y (PVY). Local lesions did not develop after similar inoculations with any one of two or more strains each of potato viruses A, M, S, X, or spindle tuber and a single strain each of potato calico and potato yellow dwarf. Inoculations from diseased specimens infected with PVY plus potato viruses A, M, S, and X, singly or in some combinations did not affect the efficiency of P.I. 230579 in detecting PVY in the mixed infections. Plants of P.I. 230579 developed significant numbers of local lesions from PVY inoculations at temperatures from 16 to 27°C and at inoculum dilutions through 1:100. Excised individual leaves of P.I. 230579 can be used to detect PVY. Leaves of plants exposed to air pollutants are unsuitable for assay purposes.S. demissum P.I. 230579 is homozygous for the local reaction to isolates of PVY and is a valuable aid for indexing aphid or mechanically inoculated potato clones or seedlings for resistance to the virus. It is a superior diagnostic host for differentiating PVY from other viruses commonly found in potatoes in the United States. 相似文献
123.
124.
A. F. Reeves R. E. Webb D. C. Merriam H. J. Murphy F. E. Manzer R. H. True 《American Journal of Potato Research》1980,57(9):429-433
Delta Gold is a medium-late maturing, round, yellowish-skinned, yellow-fleshed variety which is excellent for baking and processing. Its yields have been lower than Kennebec; however, specific gravities have been higher. It is moderately resistant to scab and early blight and immune to net necrosis and virus A. 相似文献
125.
Precision Agriculture - Soil acidification is a growing problem in semi-arid agroecosystems. In the state of Montana, USA, soil pH levels below 5.5 have been documented in nearly half of the... 相似文献
126.
The effect of crop residue incorporation date on soil inorganic nitrogen, nitrate leaching and nitrogen mineralization 总被引:7,自引:0,他引:7
R. D. J. Mitchell R. Harrison K. J. Russell J. Webb 《Biology and Fertility of Soils》2000,32(4):294-301
Delaying cultivation and incorporation of arable crop residues may delay the release of NO3
– and hence reduce leaching. The objective of this study was to investigate the effect of timing of cultivation on the mineralization
and leaching of NO3
– from an arable crop residue. Overwinter N leaching and periodic measurements of soil inorganic N were combined to estimate
net N mineralized after ploughing a crop residue into a free-draining loamy sand soil in central England on six dates from
June 1994 to January 1995. The crop residue was whole green barley with approximately 2% N. N leaching in the two following
winters was increased by the addition of crop residues. Early residue application also tended to increase N leached in the
first winter, largely as a consequence of relatively large losses early in the drainage period. Thus, early incorporation
of crop residues presents a greater leaching risk. The amount of N leached in the second (drier) winter was similar for all
dates of incorporation. At the end of the first winter, inorganic N derived from the crop residue was greatest for earlier
additions: June (40% N applied) > September (30% N applied) > August (20% N applied) > October (19% N applied) > November
(11% N applied) > January (3% N applied). However, at the end of the experiment, there was no evidence that the residues which
had mineralized least by the end of the first winter had, to any significant degree, caught up, and this was confirmed by
the parameters of the equation for first-order decomposition in thermal time. These results indicate that the effect of temperature,
particularly in the early stages of residue mineralization, is complex and interacts with other soil processes in terms of
the fate of the N mineralized.
Received: 19 July 1999 相似文献
127.
K L Bryant E T Kornegay J W Knight K E Webb D R Notter 《Journal of animal science》1985,60(1):136-144
Three trials, utilizing a total of 240 crossbred gilts, were conducted to study the influence of 0 (NB) or 220 (SB) microgram supplemental biotin/kg of diet on feedlot performance, plasma biotin and development of toe lesions in developing gilts. Corn-soybean meal diets were fed from weaning to 92 kg body weight. Gilts were housed on expanded-metal floors to 50 kg body weight and on partially slatted concrete floors until completion of the trials. Feedlot performance, hair and structural soundness scores were not different (P greater than .10) between NB and SB gilts. Plasma biotin (PB) levels were elevated (P less than .01) when supplemental biotin was included in the diet. Gilts consuming SB diets had fewer (P less than .01) toe lesions/gilt and lower (P less than .01) toe lesion severity scores/gilt compared with gilts fed NB diets. Heel-horn erosion and heel cracks were the most frequent toe lesions observed. Fewer gilts (P less than .01) developed side-wall toe cracks when fed SB diets. Supplemental biotin reduced the frequency of individual toes containing heel-horn erosion (P less than .10), heel cracks (P less than .05) and side-wall toe cracks (P less than .05) with the severity of these lesions not affected (P greater than .10) by supplemental biotin. These results suggest that biotin levels in corn-soybean meal diets are adequate for feedlot performance, and that supplemental biotin can improve hoof integrity, but will not prevent toe lesions. 相似文献
128.
Craig Webb David C Twedt 《Veterinary Clinics of North America: Small Animal Practice》2003,33(5):969-85, v-vi
Gastritis--inflammation of the stomach--is a frequently cited differential yet rarely characterized diagnosis in cases of canine anorexia and vomiting. Although the list of rule-outs for acute or chronic gastritis is extensive, a review of the veterinary literature reveals fewer than 15 articles that have focused on clinical cases of canine gastritis over the last 25 years. The dog frequently appears in the human literature as an experimentally manipulated model for the study of endoscopic techniques or the effect of medications on gastric mucosa. In the veterinary patient, cases of acute gastritis are rarely pursued with the complete diagnostic armamentarium, and cases of chronic gastritis are rarely found to occur as an entity isolated from the rest of the gastrointestinal tract. This article focuses on those findings most clinically relevant to cases of canine gastritis in veterinary medicine. 相似文献
129.
LF Crocomo F Ariu L Bogliolo D Bebbere S Ledda SD Bicudo 《Reproduction in domestic animals》2016,51(2):276-281
The efficiency of in vitro sheep embryo production is still low compared to that observed in vivo and in other species. In this context, meiotic inhibition strategies emerged as a promising alternative to improve this biotechnology. So, this study aimed to evaluate, for the first time, the effects of roscovitine on in vitro maturation of sheep oocytes and their subsequent embryo development. For this, cumulus–oocyte complexes (COCs) were cultured for 6 h in the presence (Rosco) or absence (Control) of 75 μm roscovitine and, subsequently, in vitro matured (IVM) for 18 h with gonadotropins. At 0 (Immature), 6 and 24 h of culture, the nuclear status of oocytes was evaluated by Hoechst staining. Embryo cleavage and blastocyst formation were recorded 30 h after in vitro fertilization and on day 7 of culture, respectively. Blastocyst quality was evaluated by differential staining. At 6 h, the GV rate in the Rosco treatment (93.8%) was similar to that observed in the Immature oocytes (94.9%) and significantly higher compared to Control (41.3%). After IVM for 18 h, a high and similar proportion of oocytes from Rosco (93.6%) and Control (88.4%) reached the MII stage. In both treatments, approximately 70% of oocytes cleaved and 50% of them developed up to blastocyst. The mean percentage of blastocyst cells, embryoblast, trophoblast and pyknosis did also not differ between Control and Rosco. In conclusion, roscovitine, at the studied experimental conditions, was efficient to reversibly inhibit the meiosis of adult sheep oocytes without detrimental effect on development and quality of the in vitro produced embryos. 相似文献
130.
High Correlation coefficients have been found in the application of the formula: to data for a large number of strawberries from nine cultivars. Of the terms in the equation (Total no. of achenes — C) was found to be different in different cultivars and to be related to the position of the berry on the inflorescence, but there was no constant relationship between the achene numbers in the different ranks of berry. Whether the numbers of achenes per berry can be altered by environmental or cultural treatments was not resolved. F, a term having the dimensions of weight per area, represents weight per unit area of berry surface and seems to be constant amongst plants of a cultivar subject to uniform treatment, but differs between cultivars and treatments.The number of achenes per cm2 of surface on ripe berries is a measure of berry development in the fruiting season and may be affected by environmental and managerial factors and by internal competition between fruits and leaves on the same plant.The interactions of these factors on berry size enable two stages to be recognised at which size is determined, namely during flower formation, when achene numbers and possibly F are fixed, and during fruit development after pollination when the term for spatial distribution of achenes is settled.It is suggested that an examination of the effects of different treatments on each of the size components might enable a distinction to be drawn between the influence on yield of genetic characteristics on the one hand and intrinsically variable characteristics subject to external influence on the other hand, thus clarifying the type of research and/or development needed to enable growers to achieve maximum yields. 相似文献