Jemseg: A new,early high-yielding potato variety with high resistance to virus Y and immune to virus X

Jemseg is an early sizing variety of early maturity. It has outyielded the variety Warba for total and marketable yield when dug at 80 days from planting. It has moderate resistance to common scab, is immune to virus X and has high resistance to virus Y, plus resistance to virus S. Jemseg was originated at Fredericton, New Brunswick, and is a product of the potato breeding program of Agriculture Canada. The variety has been under test in New Brunswick for 10 years as seedling F67072. It has also been tested extensively in the Maritime Provinces and throughout Canada through the facilities of regional and national evaluation trials. Jemseg was selected from a progeny of a cross between the variety Sable and a Fredericton seedling F55069. Sable is an early variety developed at Fredericton. F55069 is a Fredericton seedling bred for X immunity and scab resistance. Jemseg was first grown in the field in 1967. The pedigree follows:      

Tobique,a new chipping variety

Tobique is a chipping variety with good yield and table quality. It is resistant to Verticillium wilt,Fusarium sambucinum, Fusarium coeruleum, and virus Y. Tobique was originated at Fredericton, New Brunswick and is a product of the potato breeding program of Agriculture Canada. This variety has been under test in New Brunswick for fifteen years as seedling F61025. It has also been tested extensively in the Maritime Provinces and throughout Canada through the facilities of regional and national evaluation trials. Tobique was selected from a cross between the variety Cariboo and Fredericton seedling F45019. Cariboo was introduced in British Columbia as a maincrop variety of distinctive appearance and bruise resistance; also with resistance toVerticillium alboatrum andPhoma rot. F45019 is a late blight resistant seedling with high dry matter. Pedigree: {ie419-01}     

Evaluation of mineral oil sprays for reduction of virus Y spread in potatoes

In 1979 and 1980 field tests were made at Fredericton, New Brunswick to evaluate the effect of various oil application methods on the spread of potato virus Y (PVY) and the phytotoxicity they might cause. Control of PVY by oil sprays reached 64%. Control of spread depended largely on the concentration of the oil, and to a lesser extent, on its delivery rate. Tests did not show any significant effect of the spray pressure. There was no significant difference between eight commercial oil formulations. No significant foliar phytotoxicity or yield reduction resulted from applications of oil, except when a combination of high oil concentration (3% water emulsion) and high rate of application (2240 L/ha) was used. Fungicides mixed with oil or applied immediately after oil produced foliar phytotoxicity. Less phytotoxicity occurred when they were applied 24 h later than oil.     

The effect of green sprouting on yield of early potatoes

Three yield trials of early sizing potato seedlings and varieties were conducted at separate locations over a two-year period in New Brunswick, Canada. Two preplanting treatments of the seed were used: green sprouting for 3 weeks at 65 F (18 C) and check samples from storage at 45 F (7 C). Graded yield results and specific gravity determinations obtained 82 days after planting are presented. A highly significant increase (16–28%) in yield of marketable tubers was obtained from the green sprouted treatments. Higher specific gravities were recorded for 32 of the 43 green sprouted plots over the checks.     

Field assessment of imidacloprid to reduce the spread of PVY° and PLRV in potato

A three year field study conducted at the Potato Research Centre in Fredericton, New Brunswick, showed that imidacloprid applied in furrow at planting or twice to the foliage in mid July could result in a limited reduction of PLRV spread in the potato crop. Tests did not determine any significant effect on the reduction of the spread of PVY. The aphicidal property of imidacloprid was confirmed.     

Use of canonical discriminant analysis in assessing the merit of crosses in terms of breeding goals

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.     

Genotypic stability analysis of eight potato varieties tested in a series of ten trials

Genotypic stability analyses were carried out for five characteristics of eight potato varieties which had been tested in the New Brunswick Variety Trial in the past ten years, 1961–1970. Special attention was paid to three economic traits, i.e., marketable yield, specific gravity and dry matter yield. General adaptability was defined in this paper as having average genotypic stability and above-average mean performance. Kennebec showed the best general adaptability of marketable yield, Hunter for specific gravity and Netted Gem dry matter yield. No variety was ranked at the top for both marketable tuber yield and specific gravity. Some implications of this study on potato breeding are discussed.     

Agronomic performance and quality of oat (Avena sativa L.) genotypes of worldwide origin produced under Central European growing conditions

One hundred and twenty oat (Avena sativa L.) genotypes of worldwide origin were evaluated for agronomic and grain quality characters in three replicated field experiments in Austria and one in Germany. Panicle emergence, plant height and lodging severity were evaluated under field conditions, and grain yield, thousand kernel weight, hectolitre weight, screenings percentage > 2 mm, and groat percentage were measured after harvesting. Substantial genetic variation and high heritability were observed for all traits. The highest yielding entries were improved cultivars from European breeding programs. Groat yield and grain yield were highly correlated. For agronomic traits such as earliness and plant height, and quality traits such as groat percentage, several of the overseas genotypes, mostly from the USA and Canada, showed better performance than the European cultivars. Selected lines from the North American breeding programs appear to be valuable resources for European oat breeding programs, especially for the improvement of physical grain quality traits.     

Seed potato contamination with fusarial propagules and their removal by washing

Seed potatoes from Maine, New Brunswick (Canada), Wisconsin, Minnesota and North Dakota were examined during 4 years for contaminating fusarial propagules on tuber surfaces. The degree of contamination was estimated by counting the number of infections that developed on cut surfaces of 100 pieces cut from 50 tubers removed from the tops of 6 cwt bags. Lesion counts were made after 2-weeks incubation at 13 to 16 C. Of seventy-seven seed stocks examined, 29 developed lesions on 91–100% of the seed pieces. Twenty-four of these heavily contaminated stocks came from Maine and New Brunswick. For the different years,Fusarium solani was obtained from 70 to 90%, andF. roseum from 5 to 28% of the lesions cultured each year. BothFusaria were on potatoes from the different production areas. The infectious propagules were in soil washed or brushed from tuber surfaces, and surface-borne inoculum from the tubers. A preliminary report on identifying contamibefore cutting. Plant emergence and productivity were correlated with tuber contamination.     

Potato selection for high dry-matter in seedling generation

Potato selection for high dry-matter can be made in the first-year seedling generation reducing the time required to complete a breeding cycle to one year. Yielding capacity of first-year seedlings can be as good as that of plants from tubers of clonal generation and from commercial varieties.     

Selecting for resistance to diseases in early generations

Screening in the seedling and first clonal generations is a potentially cost-effective and efficient way to incorporate resistance to important diseases and reduce large breeding populations to manageable size. In practice, however, early screening is often limited by the need to maintain clean seedstocks of promising clones, unreliability of single-plant evaluations, associations of disease resistance with undesirable horticultural characteristics, or the higher priority placed on traits other than disease resistance. Possible methods to overcome these limitations are discussed. Examples of early generation screening for resistance to several diseases are given.     

马铃薯主要块茎性状杂种优势及配合力分析

对马铃薯9个亲本及其不完全双列杂交组配的18个杂种无性一代的8个性状进行了杂种优势和配合力分析。结果表明:①8个性状均具有一定程度的杂种优势,超中亲优势的大小顺序为:烂薯率>块茎产量>结薯数>淀粉含量>单个块茎重>薯形>块茎外观>结薯习性;超高亲优势的排列顺序则为:结薯数>单个块茎重>块茎产量>块茎外观>烂薯率>淀粉含量>薯形>结薯习性。②品种P(2L0031-17)、P(4陇薯3号)、P(7L0218-38)、P(995D-P-8)具有较好的一般配合力,是理想的亲本材料。③组合P1×P4、P2×P9在淀粉含量、块茎产量等性状上具有较高的特殊配合力,产生较强的杂种优势。在马铃薯高淀粉育种中应选择高淀粉材料作为亲本之一,选配组合时亲本最好采用高×高类型或高×低类型配置组合。     

Comparative field performance of potatoes from seedlings and tubers

A field trial was conducted at Freeville, NY to compare yields from hybrid families ofSolanum tuberosum L. with yields from their corresponding full sib, first clonal generation tubers. Unselected tubers were saved after harvesting transplanted seedlings of four Neo-Tuberosum × Tuberosum hybrids in 1982. The following year these tubers were planted for comparison with seedlings of the same hybrids in a split plot design. Total yields and yields of tubers ≥ 38 mm in diameter were respectively 34% and 38% higher from tuber propagated plants than from seedlings. The biggest difference was in tubers ≥ 63 mm diameter, where plants from tubers gave yields more than double those from seedlings. Seedlings had twice as many large axillary branches per stem as plants from tubers. Uniformity of tuber size and shape, and overall appearance ratings of tubers were better with seedling propagation; however, these comparisons are biased by the tendency of seedlings to produce smaller tubers, which inherently receive higher ratings.     

Reliability of potato selection in the first clonal generation

Studies were carried out over a seven-year period to determine the reliability of selection at the single hill stage; two clonal replicates of 200 unselected first clonal generation seedlings, and 10 established cultivars were used as test materials. Duplicate selections of clones were made in relatively few instances; consequently, the reliability of selection at the single hill stage is highly questionable. Several modifications in procedure are proposed including the application of negative selection pressure, using replication where possible, discarding only the obviously poor clones, and modifying the criteria used as a basis for selection and limiting the number of hills per clone grown the second year.     

The History of Potato (Solanum tuberosum L.) Research in Spain

Principal activities of the NEIKER-Basque Institute of Agricultural Research contributing to potato research in Spain are described from its origin in 1933 to 2004. In the first period, the genetic crosses begun and the first Spanish variety called “Eminencia” was obtained. From the 1950s (second period) the Station was divided into four sections: virology, ecology, pre-basic potato production and genetics. In 1979 (third period) a new generation of scientists was brought in to reinvigorate activities like genetic breeding and to start new ones, such as tissue culture, nematology, pathology and serology. Since the 1980s, a total of 23 varieties have been registered, which have good industrial attributes or fresh consumption characteristics.     

Nipigon: A new high-yielding,early sizing table potato

Nipigon is a high-yielding, early sizing, table potato with good boiling and baking quality and is specifically adapted to northern Ontario. It has some resistance to late blight, rhizoctonia and viruses X and Y. The Nipigon potato was bred and initially selected within the Potato Breeding Project at the Fredericton Rcsearch Station of Agriculture Canada. This variety has been under test as seedling F61051 since 1965 throughout eastern Canada, but mostly in Ontario. Nipigon was selected from the progeny of a cross between two Fredericton seedlings; F53026 an early, scab-resistant seedling with very good tuber type and F51043, which has good processing quality and resistance to the common races of late blight,Phytophthora infestans (Mont.) de Bary. The pedigree is as follows:      

EMS诱导的盛农1号小麦突变体筛选与鉴定

突变体诱导是创造小麦遗传材料和选育新品种的重要途径之一。通过甲基磺酸乙酯（EMS）处理高产、抗白粉病品系盛农1号,从4 500个M₂代穗系中筛选出174个突变体穗系,突变率为3.86%。其中,穗部突变体32个,突变率为0.71%;叶部突变体47个,突变率为0.89%;茎部突变体22个,突变率为0.49%;育性和成熟期突变体12个,突变率为0.27%;其他类型突变体11个,突变率为0.24%;农艺性状优于对照盛农1号的突变体57个,突变率为1.27%。经过M₃代验证及生物学性状和农艺性状调查,获得可稳定遗传的株系18个,其中,穗部突变体6个,茎秆突变体1个,叶部突变体6个,早熟突变体3个,晚熟突变体2个。农艺性状分析表明,穗部突变体SS4、SS5、SS6和SS16的小穗性状优于盛农1号。这些新突变体为小麦品种改良和遗传研究提供了新的材料。     

Discriminating Russet Norkotah intraclonal selections using canonical and cluster analysis

Intraclonal selection has been used to develop improved versions of existing popular potato cultivars. The approach is usually undertaken to overcome trait deficiencies that limit production/acceptance of the cultivar. Because of close genetic relationships, discriminating between strains and the original cultivar is more difficult than discriminating between conventionally derived hybrid cultivars. The objective of this investigation was to determine the genetic relationship between several Russet Norkotah intraclonal selections (strains) using statistical analysis. Russet Norkotah and seven Russet Norkotah strains (TXNS102, TXNS112, TXNS223, TXNS278, TXNS296, CORN3 and CORN8) were grown in 2000 and 2001 in New Brunswick, Canada, and several plant and tuber traits were measured. Hierarchical cluster analysis and canonical discriminant analysis demonstrated that the Russet Norkotah strains differ in a significant manner from the original cultivar and are therefore distinct and unique cultivars.     

Utilization of potato genetic resources in variety development

Potato varieties of Europe, widely grown prior to the late blight epidemic of the 1840s, were apparently derived mainly from ChileanSolanum tuberosum Group (Gp) Tuberosum and with contributions from Gp Andigena. A small number of these old varieties had field resistance and consequently survived the late blight. These survivors, along with a limited number of 19^th and early 20^th century introductions, provided the very narrow genetic base for our modern potato variety development. Beginning in the first half of the 20th century, resistance to diseases and pests from exotic species and primitive relatives was backcrossed into the existing parental stocks, with little improvement in broadening of the genebase. By the 1980s, 77% of European and somewhat fewer North American varieties had genes, derived by backcrossing, fromS. demissum (late blight resistance) and Andigena (resistance to cyst nematode). Broadening of the Tuberosum genebase was undertaken in 1959 by creating long-day adapted Neo-Tuberosum (N-T) from large populations of Andigena. This took six or more cycles of recurrent mass selection. Simmonds, in England, was the first to begin this work, followed shortly after by Plaisted, in the U.S., and Tarn, in Canada. Varieties with N-T in their pedigrees include the New York releases “Rosa”, which is 50% N-T, and “Eva”, 25% N-T. The Tuberosum genebase has also been broadened with diploid Gp Phureja resulting in the releases of “Yukon Gold,”with yellow flesh and high internal quality, and “NorValley,”a chipper with resistance to cold sweetening. Over 5000 accessions of about 150 wild species are available to breeders from the U.S. Department of Agriculture, National Research Support Project 6 (NRSP-6) genebank. Many of these accessions have been evaluated for resistance to diseases and pests as well as other important traits. Six genebanks in other countries also have many accessions for breeders. These seven collections are a great source of valuable traits for breeding, but remain under-utilized, mainly because of the time and additional resources required in eliminating the “wildness”characters associated with the desired traits. “Pre-breeding”is needed to help breeders utilize the many needed genes and alleles in the wild species. There now are two projects with pre-breeding as an objective in the U.S., one at Madison, WI, and the other at Prosser, WA. Resistance to cold sweetening (low sugar build up in cold storage) has been backcrossed from several wild species into the Tuberosum background, as has resistance to late blight, the Columbia rootknot nematode, and the potato leafroll virus (PLRV). Resistance to potato virus Y (PVY) and PLRV obtained from N-T has been incorporated into Tuberosum parental stocks. Durable resistance to late blight in Polish breeding stocks, withS. demissum andS. stoloniferum background, and in improved Bolivian and Peruvian Andigena has also been utilized by North American programs.     

引进美国甘蔗种质工艺品质演进分析及发掘

本研究主要基于投影寻踪分类法（PPC）对引进美国甘蔗种质主要工艺品质性状进行世代演进和种质评价分析。根据育成或改良年代（10~20 a为时间界点）把引进的58份美国甘蔗种质划分4个改良世代,基于大田试验,对甘蔗锤度、甘蔗蔗糖分、蔗汁蔗糖分、甘蔗纤维分、甘蔗简纯度等5个重要工艺品质性状指标进行方差、投影寻踪分类和聚类分析,以揭示其世代演进特征和筛选工艺品质优异种质资源用于杂交育种。方差分析表明,世代内和世代间各种质资源工艺品质性状存在显著差异（P<0.05）,变异系数在2%~20%之间,其中甘蔗蔗糖分、蔗汁蔗糖分和简纯度3个品质性状还存在世代和月份间的显著交互作用。投影寻踪分类法评价分析表明,不同世代美国甘蔗种质资源投影值差异显著,其中以第1代最低,依次增加,第4代最高;投影方向以甘蔗蔗糖分最高,依次为蔗汁蔗糖分和甘蔗锤度,简纯度和纤维分最低。根据投影值大小的聚类分析表明,58份种质可以划分为4类。筛选了主要工艺品质性状优良的甘蔗种质18份（第Ⅱ类）用于杂交育种,其中来自第4代的材料有6份,占第4代材料总数的46.15%;来自第3代的材料有10份,占总数的37.07%;来自第2代的材料有1份,占总数18.18%;第一代材料未筛选出品质优良种质资源。以上结果可以看出,美国甘蔗种质资源主要工艺品质改良显著,随着世代演进而显著提升。表现优异外引种质以第4代所占比重最高,依次递减,第一代最少,优异种质多来源于演进次数最多的世代;投影寻踪分类法可作为甘蔗改良效果和种质资源评价研究的另一途径。