Mainechip: A new chipping potato variety for cool storage processing     

A. F. Reeves  G. A. Porter  F. E. Manzer  T. M. Work  A. A. Davis  E. S. Plissey 《American Journal of Potato Research》1994,71(4):237-247

TheMaineChip potato variety is medium-maturing and has round, whiteskinned, white-fleshed tubers with shallow eyes, high specific gravity and moderate yields. Its major use is expected to be as a storage chipping variety since sugar build-up in storage is slow, and reconditioning is possible. This variety can be chipped directly from 7 C storage.MaineChip does not show the net necrosis caused by potato leafroll virus and is moderately tolerant to verticillium wilt (Verticillium alboatrum) and rhizoctonia (Rhizoctonia solani). It is also moderately resistant to blackspot and shatter bruise. Hollow heart is its major internal quality defect, being a problem in ten of the twenty-nine regional tests conducted over five years.  相似文献   

Coastal Chip: A chipping potato variety resistant to heat stress     

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   

Relation of potato size to after-cooking blackening tendency     

James Siciliano  E. G. Heisler  W. L. Porter 《American Journal of Potato Research》1969,46(3):91-97

An observation made in the laboratory led to a two-year study showing a relationship between after-cooking discoloration and potato size. This relationship, the larger the potato the greater the blackening tendency, was consistent for all potatoes examined in this sudy whether they blackened severely or slightly. These findings may help future researchers correct the conditions that cause blackening.  相似文献   

Yield,market quality and petiole nitrate concentration of non-irrigated Russet Burbank and Shepody potatoes in response to sidedressed nitrogen     

Gregory A. Porter  Jonathan A. Sisson 《American Journal of Potato Research》1993,70(2):101-116

Russet Burbank and Shepody potatoes were grown with the following four nitrogen treatments: 1) 90 kg ha^?1 at planting; 2) 180 kg ha^?1 at planting; 3) 90 kg ha^?1 at planting followed by an additional 90 kg ha^?1 side-dressed after tuber initiation; or 4) 90 kg ha^?1 at planting followed by an additional 45 kg ha^?1 sidedressing. When compared to the 90 kg ha^?1 at-planting treatment, petiole NO₃-N concentrations increased rapidly after sidedressing and were relatively constant through mid-season. Sidedressed N significantly increased total yields relative to the 90 kg N ha^?1 at-planting treatment by an average of 5.0 t ha^?1 in three of nine experiments. Three of the experiments, where yields did not significantly increase, were on sites which were not expected to respond to supplemental N based on petiole NO₃-N testing. A red clover green manure crop was the previous crop for two of these experimental sites. Petiole NO₃-N testing criteria were only partially effective in detecting sites where response to sidedressed N occurred. When compared to a single application of 180 kg N ha^?1 at planting, split application of 90 kg N ha^?1 at planting followed by a 90 kg N ha^?1 sidedressing significantly reduced total yields in one of nine experiments and did not affect yields in the remaining eight experiments. Tuber uniformity was improved in three of nine experiments by the split-N treatment. Specific gravity was not significantly affected. Use of 45 kg N ha^?1 at side-dressing resulted in similar yield as the 90 kg N ha^?1 sidedressing, although yield of large-sized tubers was often decreased with the lower N rate. Use of reduced at-planting N rates followed by sidedressed N does not appear to increase yields of non-irrigated Russet Burbank and Shepody potatoes when compared to the at-planting N rates that are currently recommended. This management approach can maintain yields at levels comparable to at-planting N programs and does provide an opportunity to reduce N application rates on sites where soil N reserves and soil amendments may make a substantial N contribution to the potato crop. Side-dressed N application can frequently improve yields and tuber size when potatoes have been underfertilized at planting; however, some inconsistency in response can be expected in regions that rely on unpredictable natural rainfall.  相似文献   

Response of Russet Burbank and Shepody potatoes to nitrogen fertilizer in two cropping systems   总被引：1，自引：0，他引：1  

G. A. Porter  J. A. Sisson 《American Journal of Potato Research》1991,68(7):425-443

Russet Burbank and Shepody potatoes were grown with at-planting N fertilizer rates ranging from 0 to 270 kg ha^?1 during 1986 through 1989. Experiments were conducted each year following small grains and red clover. Total yields and tuber size were strongly increased by N on most sites where potatoes followed small grains. Specific gravities declined with increasing N rate. Total yields of Russet Burbank and Shepody were optimized at an average of 196 and 211 kg ha^?1 of N, respectively, following small grains. The effect of N fertilizer on yields was much less dramatic following red clover. Total yields averaged 88% of maximum with only 45 kg ha^?1 of N applied, compared to 77% of maximum for this N rate following small grains. Total yields for the two varieties were optimized at 126 and 136 kg ha^?1, respectively. U.S. #1 yields were generally not increased at N rates above 45 to 90 kg ha^?1 following red clover and tuber size was not increased at rates above 90 to 135 kg ha^?1. Based on these studies, the N fertilizer credit for red clover grown prior to potatoes can be up to 75 kg ha^?1. Maintenance of tuber quality necessitates conservative use of N fertilizer when potatoes are grown following legumes. The highest N rates tested suppressed total yields of Russet Burbank, a late-season, indeterminate variety, by approximately 9% averaged over cropping systems.  相似文献   

A note on the melting point of α-solanine     

William L. Porter 《American Journal of Potato Research》1972,49(10):403-406

A discussion of the problems involved in the determination of the melting point of α-solanine is combined with an estimation of the reliability of this physical property for establishing the purity of a preparation.  相似文献   

Reconciling alternative models of phenological development in winter wheat     

P.D. Jamieson  I.R. Brooking  M.A. Semenov  G.S. McMaster  J.W. White  J.R. Porter 《Field Crops Research》2007

Simulation of the timing of anthesis in wheat crops is achieved using two very different approaches. The older of these simulates progress to flowering by calculating the duration of phases between significant events on the shoot apex. The alternative method tracks development through leaf appearance, using the prediction of final mainstem leaf number to control the duration of the phase from emergence to flowering. Although these methods appear to differ substantially, we show in this paper that the number of leaves on the mainstem when the stage of terminal spikelet occurs is extremely tightly coupled to final mainstem leaf number. We conclude that accurate prediction of the terminal spikelet stage or similar prediction of mainstem leaf number amount to the same thing, so reconciling the methods.  相似文献   

Chemical composition of potatoes. VIII. Effect of variety,location, and year of growth on the content of nitrogen compounds     

Eugene A. Talley  Thomas J. Fitzpatrick  William L. Porter 《American Journal of Potato Research》1970,47(7):231-244

Free amino acid content, total nitrogen, extractable nitrogen, ratio of extractable to total nitrogen, solids content, and specific gravity in Cobbler, Katahdin, Kennebec, Red Pontiac, and Russet Burbank potatoes was studied. Each variety was grown in six different locations (Idaho, Maine, Pennsylvania, Wisconsin, Long Island, and the Red River Valley) during the years 1961 through 1963. The mean values for each factor, with significant differences indicated, are listed along with the high and low range, the coefficient of variation and the overall mean. The percent of total variance contributed by each of the variables and their interactions also are listed. Long Island potatoes had the highest nitrogen and amino acid content. Varietal differences were less significant. Proline was the most variable of the constituents measured. Aspartic and glutamic acids had the highest variability with respect to years grown. The effect of each variable varies from one constituent to another.  相似文献   

Factors that impact on the ability of biofumigants to suppress fungal pathogens and weeds of strawberry   总被引：1，自引：0，他引：1  

S.W. Mattner  I.J. Porter  R.K. Gounder  A.L. Shanks  D.J. Wren  D. Allen 《Crop Protection》2008,27(8):1165-1173

This research aimed at identifying factors that improve the efficacy of biofumigants for soil disinfestation against strawberry (Fragaria×ananassa) pathogens and weeds. In laboratory bioassays, volatiles released from the macerated roots of a Brassica rapa/Brassica napus biofumigant crop were six times more effective at suppressing the growth of the strawberry pathogen Rhizoctonia fragariae than shoots. Furthermore, the toxicity of the volatiles from the biofumigant crop to R. fragariae increased as plant developmental stage progressed. These results related to the release of higher quantities and greater diversity of isothiocyanates (ITCs) from the roots of mature biofumigant plants than from their shoots. Separate bioassays showed that volatiles from the biofumigant crop suppressed the growth of six different soil-borne pathogens (Alternaria alternata, Colletotrichum dematium, Cylindrocarpon destructans, Fusarium oxysporum, Pythium ultimum, Phytophthora cactorum, and R. fragariae) of strawberry and seven Trifolium spp. (clover) weeds. The suppression of Trifolium spp. by biofumigant volatiles did not relate to their seed size, but might relate to their hard-seededness or genotype. In the field, rotary incorporation of the biofumigant crop did not produce detectable levels of ITCs in soil; reduce the survival of the strawberry pathogens, P. cactorum and C. destructans; or affect populations of culturable soil microflora. Yet, it suppressed the growth of emerging weeds by 40% and the growth of P. cactorum by 20%. We hypothesise that allelochemicals other than ITCs, such as nitriles, or other biological mechanisms might also play a role in biofumigation. A key to improving the efficacy of biofumigation in the field seems to lie in the development of application technologies that can macerate and incorporate biofumigants evenly in soils, in addition to incorporating biofumigants under optimal edaphic conditions for release of ITCs.  相似文献   

Environmental influences on melatonin secretion in Atlantic cod (Gadus morhua L.) and their relevance to commercial culture     

M.J.R. Porter  S.O. Stefansson  G. Nyhammer  Ø. Karlsen  B. Norberg  N.R. Bromage 《Fish physiology and biochemistry》2000,23(3):191-200

This study investigated the effects of photoperiod and temperature on plasma melatonin secretion in Atlantic cod (Gadus morhua L.). Initial work confirmed the presence of a diel profile of melatonin synthesis, with elevated levels during the dark phase. Unusually for fish, the peak in plasma melatonin occurred towards the end of the dark phase, which is indicative of a type `A' melatonin profile. When exposed to 60 hours of continuous darkness a clear endogenous rhythm of melatonin synthesis was observed, which continued for 4 cycles with a periodicity which, approximated to 24 h. When acclimated to varying temperatures (4, 8, 12 or 16 °C) no variation in melatonin production was seen, however, body size appeared to be an important influence, with the smallest fish exhibiting significantly higher levels of dark phase melatonin. Finally, the application of additional night-time illumination to cod maintained in sea cages i.e. without blackout, did not significantly reduce dark phase plasma melatonin, suggesting that cod are less sensitive to photoperiod manipulation in cages than salmonids.  相似文献