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81.
Field trials demonstrated that agricultural wastes could be successfully composted in the winter with the passively aerated windrow system. Three small windrows were constructed. One pile contained a sheep manure-straw mixture, while the other two piles contained varied amounts of horse manure, cow manure, and bedding materials (straw, wood chips). The piles were constructed on a porous base of wood chips. Standard four-inch (10 cm) perforated pipes were placed approximately three feet apart in the porous base, perpendicular to the length of the windrow. Piles were covered with 15 to 20 centimeters of finished compost. A commercial compost covering fabric permeable to gases and water vapor but impermeable to liquid water was used for additional insulation and protection against high winds. Ambient temperatures ranged from ?27°C to 15°C during the trials. Initially, all three piles froze. Then the ends of the piles began to heat up, with the southern ends which received the most sunlight heating up first. Plugging the pipes seemed to help the piles heat up faster, but did not appear to be necessary. Thermophilic temperatures were attained and the composting cycle took 50 to 80 days after the piles heated up. Oxygen levels were highest at the bottom of the pile, and decreased as one moved to the top of the pile. The biggest practical problem encountered was the snow drifts that periodically formed at the windrow base, covering the pipe openings. 相似文献
82.
D. R. Lynch N. Foroud G. C. Kozub B. C. Fames 《American Journal of Potato Research》1995,72(6):375-385
A study was conducted over a three year period in southern Alberta to establish the yield and quality responses of eight potato varieties-Atlantic, Conestoga, Norchip, Niska, Shepody, Ranger Russet (Idaho clone), Ranger Russet (Amisk clone) and Russet Burbank to a single transient moisture stress (-80 kPa) at three growth stages in crop development (early, midseason and late). Early and midseason moisture stress had the greatest negative impact (P<0.05) on tuber yield. Of the eight varieties, Atlantic and Conestoga appear to be particularly sensitive to stress at these two growth stages. Midseason stress also appeared to reduce specific gravity. A year x stress interaction (P<0.05) for fry color suggests that the influence of moisture stress on fry color can be modified by other environmental factors. The results of the study demonstrate the importance of maintaining adequate soil moisture at all stages during crop development. 相似文献
83.
D. R. Lynch L. M. Kawchuk C. A. Schaupmeyer J. Holley D. K. Fujimoto D. Driedger T. R. Tarn D. Waterer J. Wahab M. S. Goettel 《American Journal of Potato Research》2001,78(5):339-343
AC Maple Gold is a high-yielding oval/oblong, yellow-fleshed potato with an attractive appearance for the fresh market coupled with excellent french fry quality. The cultivar can be harvested early for french fry processing, but also maintains excellent fry quality during long-term storage. AC Maple Gold produces french fries with a uniform deep yellow color. 相似文献
84.
L. M. Kawchuk D. R. Lynch J. Thomas B. Penner D. Sillito F. Kulcsar 《American Journal of Potato Research》1996,73(8):325-335
With the continued introduction of new potato cultivars, accurate identification is becoming difficult but is essential for maintaining cultivar integrity and Plant Breeders’ Rights. Hypervariable DNA sequences, referred to as simple sequence repeats (SSRs) or microsatellites, have been reported to be an excellent source of genetic markers. To determine the abundance, distribution, and composition of SSRs withinSolanium tuberosum, 252 sequences were searched for tetranucleotide and smaller SSRs with a minimum length of 20 nucleotides and a maximum discrepancy of two nucleotides. In total, 40 unique SSRs were observed in the 252S. tuberosum sequences examined and occurred at a frequency of one SSR every 8.1 kb. To assess the ability of site-specific amplified SSRs to identify potato cultivars, a simple (TCAC)m and compound (TCAC)m ? (CTT)n SSR 5’ to the starch synthase gene and a compound (C)p ? (CT)q ? (AT)r ? (G)s SSR 5’ to the sequence encoding mature proteinase inhibitor I, were examined and shown to produce unique DNA profiles for 73 of 95 tetraploid cultivars. In total, 24 alleles were observed at these loci and the accurately sized amplified DNA products can be used to establish a database for cultivar identification. Site-specific amplified alleles were somatically stable and have been conserved in clonal variants of Russet Burbank independently maintained for almost seven decades, a characteristic essential for cultivar identification. As genetic markers, the abundant, informative, and easily examined site-specific amplified alleles of SSRs are ideal for quickly and accurately determining cultivar identity of S.tuberosum ssp.tuberosum. 相似文献
85.
D. R. Lynch M. S. Goettel L. M. Kawchuk D. K. Fujimoto S. J. Peloquin C. A. Schaupmeyer J. Holley D. Driedger D. Waterer J. Wahab 《American Journal of Potato Research》2001,78(5):327-332
AC Glacier Chip has a maincrop maturity, higher yields than Snowden and excellent quality (color and dry matter) for the chip industry. The tubers are oval and very uniform in size with white flesh. It performs best under irrigated conditions. AC Glacier Chip provides the industry with a high-yielding chip cultivar that produces excellent quality fried product out of the field and from long-term storage. 相似文献
86.
D. R. Lynch G. C. C. Tai D. A. Young G. B. Schaalje 《American Journal of Potato Research》1983,60(8):607-615
The Agriculture Canada Potato Breeding Program in New Brunswick is the source of new germplasm for co-operative breeding projects in other regions of Canada. Selection under maritime conditions in early clonal generations is conducted at Fredericton, New Brunswick prior to shipment of seedlings to these projects. An evaluation of this system was required with the advent of a new breeding project at the Lethbridge Research Station, Alberta, in 1979 for the Prairie region of Canada. Two groups of first field generation seedlings obtained from the Fredericton breeding program were compared in Alberta. One group was composed of seedlings obtained at random and the second of seedlings obtained through the normal selection procedures used at Fredericton. Ten crosses were sampled in 1979 and twelve in 1980. Results of the study provide evidence that pre-selection in the first clonal generation at Fredericton significantly (P < 0.05) improves the maturity, yield, and tuber traits of these seedlings grown in Alberta, yet does not cause a major reduction in the variability of traits. 相似文献
87.
88.
D. R. Lynch G. B. Schaalje G. C. C. Tai D. A. Young 《American Journal of Potato Research》1987,64(8):385-395
Canonical Discriminant Analysis was investigated as a means of assessing the merit of crosses in relation to established commercial cultivars and breeding goals. The progeny (30 per cross) of 22 crosses was evaluated in field plots at the Vauxhall Substation of the Lethbridge Research Station (Alberta). Mean values of the progeny of each cross for vine maturity, marketable yield, tuber size, tuber appearance and specific gravity were used to measure the overall merit of crosses in comparison to commercial cultivars. Breeding goals were established by calculating a 10% improvement in various combinations of the traits measured and then substituting these values in the canonical equations and computing theoretical values for the canonical variates. The canonical diagrams provided a precise and logical assessment of the relationship among cross means, control cultivars, and the breeding goals. Based on the evaluation of the 22 crosses, breeding goals for improvements in vine maturity, tuber size, marketable yield, and specific gravity over trait values obtained for Norchip and Russet Burbank, were realistic for the 1979 cross series but not for Norchip for 1980. 相似文献
89.
Niska: A maincrop chipping potato cultivar with high specific gravity and good quality after storage
D. R. Lynch D. Kichefski S. Peloquin C. S. Schaupmeyer L. la Croix D. Waterer Wm. T. Andrew J. Holley N. Crowe B. McConnell G. A Nelson B. Rex 《American Journal of Potato Research》1991,68(3):143-149
Niska is a white-skinned, white-fleshed potato cultivar with a maincrop maturity, stable yield and chipping quality and good storage characteristics. It has considerable resistance to Common scab, Early blight, PLRV, PVY and PVS. Evaluation conducted by chip processors in Alberta and Ontario, under commercial conditions, indicates that the cultivar has good storage characteristics. 相似文献
90.
Summary Apical explants from sprout tissue, cultured in vitro, of potato tubers (cv. Russet Burbank) infected withCorynebacterium sepedonicum were demonstrated to be free of the pathogen. The material remained free of the pathogen through three in vitro generations
and through two tuber generations produced from the in vitro plantlets.
Contribution 3878878. 相似文献