Studies on field resistance of strawberry varieties to Phytophthora fragariae

Summary Strawberry varieties were grown in a field infected with several races of Phytophthora fragariae and scored for resistance to red core disease caused by this fungus. Field resistance of a variety assessed in this way was not related to its pattern of immunity to specific races of the fungus. Possible mechanisms of field resistance were investigated by examining primary root regeneration and the amount of red steles developed in plants grown in infected soil. The least red steles were found in the roots of 53Q13, a highly field resistant Fragaria virginiana derivative. In the fairly field resistant varieties Crusader, Talisman and Templar, resistance was associated with a high capacity for root regeneration. No explanation was found for the field resistance of Cambridge Favourite.The design of a successful screening technique needs to take account of top growth because no single plant characteristic was universally linked with field resistance.     

5个工业大麻品种对5种重金属污染土壤的修复潜力

Uptake and translocation of lead (Pb), zinc (Zn), copper (Cu), cadmium (Cd), and arsenic (As) in industrial hemp genotypes were investigated at seedling and physiological maturity, in order to provide an insight for phytoremediation of mining soils in Yunnan. The experiment was conducted using five main varieties of industrial hemp viz., Yunma (ym)1, ym2, ym3, ym4, and ym5 under mining areas of Yunnan. Results showed that uptake and translocation of Pb, Zn, Cu, Cd, and As in all hemp genotypes were high at the seedling stage. Accumulation of Pb, Zn, Cu, Cd, and As contents in hemp roots were higher at physiological maturity as compared to seedling stage. However, comparing to seedling stage, Pb, As, and Cd contents in stems and leaves were higher at physiological maturity stage. Translocation factor coefficients of hemp stem and leaf to all heavy metals were more than 1.0 at seedling stage. At physiological maturity stage, translocation of Pb, As and Cd in stems and leaves of all hemp varieties were higher compared with Cu and Zn. The accumulated contents of Pb, As, Cu, Cd, and Zn in plants were 31.65-644.29, 365.14-624.25, 180.65-194.06, 15.13-24.40, and 540.07-684.27 g hm ^-2, respectively. However, highest contents of Pb, As, Cd, and Zn were observed in hemp variety Yunma 1 and Yunma 5, which suggested that these two varieties had significantly higher metal accumulation and translocation compared to other varieties. In conclusion, the bioconcentration ratios, translocation factor and phytoremediation ability of hemp variety Yunma 1 and Yunma 5 were higher than those of Yunma 2, Yunma 3, and Yunma 4. These results showed that both Yunma 1 and Yunma 5 were potential candidates for remediation of heavy metal polluted areas in Yunnan.     

Dormancy and chilling requirement of strawberry varieties for early forcing

Summary Breeding strawberry varieties for early forcing in glasshouses by heating and long-day illumination has certain aspects deviating from breeding varieties for the open. Varieties for early forcing must respond quickly on forcing by an adequate vegetative development, and early flowering and fruiting.It is essential that, prior to forcing, the dormancy of the plants is broken by means of adequate chilling.In phytotron experiments three varieties, used for forcing in the Netherlands, Glasa, Gorella and Redgauntlet, were compared with the American varieties Florida 90 and Tioga as to duration of dormancy and to chilling requirement. Judged by the degree of elongation of the plants, Florida 90 and Tioga showed the least chilling requirements. Than followed Glasa while Gorella clearly needed more chilling and Redgauntlet most.The time of flowering was independent of the degree of dormancy and of the growth response of the plants. In breeding for early forcing a short dormant period will have to be combined with early flowering.     

Implementation of simple sequence repeat markers to genotype Florida strawberry varieties

Simple sequence repeats (SSRs or microsatellites) are frequently used as a robust, rapid, and relatively inexpensive means of genotyping. Recent reports in cultivated strawberry (Fragaria × ananassa) have identified a widely applicable set of SSRs that permits discrimination of closely-related genotypes. In the present study this same set of SSRs is analyzed in cultivars commonly grown in the state of Florida, as well as advanced breeding selections from the University of Florida program. Nine primer pairs have been used to produce discrete SSR patterns for all lines tested, including diagnostic sets that distinguish between closely-related cultivars and/or breeding selections. A comparison of markers to known pedigrees is presented, along with analysis of relative relatedness between lines studied. We also detail important technical considerations for transferability and limitations of these technologies between laboratories. The resulting genotype data for cultivars commonly used in Florida are accessible as supplemental data in graphic format and allow comparison with other cultivars. Users can thus select the most diagnostic SSRs to test the lines in question. These resources provide new tools for breeders and nurseries to authenticate genotypes, follow inheritance patterns and enforce patent protection. As important, this report underscores the strengths and weaknesses of applying the original methodologies to a different plant population in independent laboratories.     

5个香料烟品种3地2年的区域适应性研究

为了提高中国混合型卷烟的质量,选育适合不同生态区域种植的香料烟新品种.采用田间比较试验的方法,在保山市和德宏州的3个香料烟产区对5个香料烟品种进行了2年适应性研究,结果认为,对照品种'云香巴斯玛1号'表现稳定,应继续作为主栽品种;'保加利亚巴斯玛'和'巴斯玛14号'的品种特性、外观质量和烟叶产质量表现较好,可逐步扩大试...     

Earliness of flowering and fruiting of forty strawberry varieties; A statistical study

Summary For the purpose of strawberry breeding the earliness of flowering and the rate of fruit development of strawberries should be considered two independent properties. This is the main conclusion from a statistical study of the dates of flowering and harvest of 40 varieties in one-year-old plants grown in the open.Further it was found that in a number of varieties the date of first flowers is influenced by the temperature in November, that is, a warm November delays flowering.The vigour of the plant appeared not to be correlated with the date of flowering.Certain high temperatures appeared to depress the rate of fruit development.     

Morphological traits and high resolution RAPD markers for the identification of the main strawberry varieties cultivated in Argentina

Eight genotypes of the main Fragaria×ananassa cultivars grown in Argentina were analysed using the random amplified polymorphic DNA (RAPD) technique combined with electrophoresis in polyacrylamide gels. The high resolution of this procedure allowed the detection, with only 13 random primers, of 37 genotype‐specific bands that can be used as markers for verifying the identity of cultivars. By using this approach, three different accessions of the cultivar ‘Pájaro’ exhibited differences in amplification profiles, confirming the need for DNA analysis to prevent misidentification of cultivars. In addition, RAPD bands and morphological traits were used to assess genetic relatedness among cultivars. Comparison of both dendrograms revealed that there is no correlation between the clustering obtained with molecular and morphological characters.     

Effects of temperature pre-treatments on the forcing of strawberry plants (cv. Glasa)

The results of an experiment, designed to study the effects of certain temperature treatments during the autumn season on the subsequent development of strawberries (cv. Glasa) during forcing, have been presented in this paper. This study was under-taken in the interest of both breeding new varieties suitable for forcing and improving the present forcing methods.Practical experience has shown that the chance of success is small when forcing is started before the 15th of January.In a recent publication it has been suggested to provide plants with strong artificial light for assimilation, which would make it possible to start forcing at an earlier date.In the present experiment, however, in which forcing was started as early as the 5th of January, good results were obtained under ordinary light conditions by previously exposing the plants to 12°C for three weeks in November. The pre-treated plants showed earlier flowring and fruiting, better fruit set and a higher yield than the control plants.These observations indicate that in order to obtain satisfactory results the inflorescences must have attained a certain stage of development at the beginning of forcing, and that this stage was reached at an earlier date by the accelerating effect of the temperature treatment.     

The production of multispecific octoploids from Fragaria species and the cultivated strawberry

Summary A method of incorporating genetic material from five species of Fragaria and the cultivated strawberry into fertile octoploids is described. A synthetic octoploid derived from a hexaploid x diploid hybrid was crossed to octoploid cultivar breeding lines until a BC₂ hybrid was produced. A second synthetic octoploid in which two diploid species and a tetraploid species were combined was crossed to a cultivated strawberry to produce a hybrid breeding clone. The two breeding clones were crossed and 222 seedlings were produced. The seedlings were generally vigorous and fruitful, some having commercial potential.     

Influence of suboptimal temperature on biomass production of potato populations of Andean and European origin

Summary Plants grown from seed derived by crossing conventional European S. tuberosum material were compared with plants grown from seed derived by crossing S. tuberosum with various, Andean frost resistant tuberbearing Solanum species. Biomass growth at optimal (20°/10°) and suboptimal (10°/4°) temperatures was studied.Differences in increase of fresh and dry matter were found between populations of Andean and European orgins at 10°/4°. At 20°/10° no such differences were found.At suboptimal temperature, Andean hybrids produced significantly more fresh and dry matter than European crosses in two harvests (64 and 178 days old plants). Statistically, Andean hybrids were found to produce the same amount of dry matter per day at both temperatures, over the complete growth period.Height increase and flower development were strongly depressed in European crosses under the suboptimal temperatures, but much less so in Andean crosses.The Andean material appears to be an under utilized resource in potato breeding for cool climates.     

Environmental impact assessment of open field and greenhouse strawberry production

A cradle-to-farm-gate life cycle assessment (LCA) study is conducted for open-field (OF) and greenhouse (GH) strawberry cultivation in Guilan province, Iran. The initial data including input materials and energy inputs exercised during production season was collected from 33 greenhouse holders and 77 farmers in the studied region. Data for the production of used inputs were taken from the EcoInvent^®2.0 database, and SimaPro software was employed to analyze primary data. Ten impact categories including Abiotic Depletion potential (AD), Acidification potential (AC), Eutrophication potential (EU), Global Warming potential for time horizon 100 years (GW), Ozone Depletion potential (OD), Human Toxicity potential (HT), Freshwater and Marine Aquatic Ecotoxicity potential (FAET and MAET), Terrestrial Ecotoxicity potential (TE), and Photochemical Oxidation potential (PhO) were selected based on CML 2 baseline 2000 V2/world, 1990/characterization method. One ton of produced strawberries was chosen as the functional unit. The evaluations of the study indicated that OF production system in all selected impact categories was more environmentally profitable than GH production system except AC and EU. Based on the results electricity, natural gas and N-based fertilizers in both production stage and application in GH strawberry production produced the most environmental burdens. Moreover, artificial neural networks (ANNs) and adaptive neuro-fuzzy inference systems (ANFIS) were compared to model environmental indices of strawberry production on the basis of input materials. The results revealed that ANFIS models due to employing fuzzy rules are able to predict ten environmental indices with minimum error and the highest accuracy.     

Influence of pollination modes on yield components in strawberry (Fragaria×ananassa Duch.)

The effects of self, wind and open pollination on yield components were investigated in five strawberry genotypes, the cultivars ‘Dukat’, ‘Paula’, ‘Redgauntlet’, ‘Senga Sengana’ and the breeding clone B-302. Investigations were also conducted to look for additional plant characteristics associated with strawberry yield components after various modes of pollination. Such characteristics would facilitate the indirect selection of highly self-compatible strawberry genotypes. The greatest effect of self pollination was observed in B-302 and ‘Redgauntlet’, while the least effect of autogamy was shown m Paula. Conversely, the last cultivar revealed the greatest effect of entomophily, whereas the greatest effect of wind pollination was observed in ‘Dukat’. Relationships between yield components and some flower and pollen characteristics after various pollinations indicated that the degree of self compatibility in strawberry can be predicted from the pollen grain length and the pollen size index. Genotypes producing long pollen grains with large size indices exhibited the greatest effect of autogamy. Anther size, especially length. Which correlated more strongly with yield components than width, could also be used as an index of autogamy in the strawberry. Pollen yield per flower an self compatibility.     

The effect of temperature on pollen production in carnations

Summary For breeding carnations the supply of good pollen may be a problem. For this reason the effect of temperature on pollen production in carnations was studied.In phytotron experiments a temperature of 23°C proved to be the optimum.     

The breeding of hybrid varieties and the production of hybrid seed in spinach

In spinach the breeding of hybrid varieties is attractive because this may result in a heterosis and/or a transgressive effect. Resistance to downy mildew [Peronospora spinaciae (Mont.) de By] and against mosaic (Cucumis virus 1) can be combined rather easily, since in both cases the resistance depends on one dominant gene. Besides a hybrid variety excludes the growing of later generations.However, a careful removal of all pollen-producing plants demands so much labour that a production of hybrid seed on a commercial scale involves great difficulties. The creation of an entirely female variety would be a solution for this problem. An outline has been given of the way in which such a variety can be developed, starting from purely female and from intersexual plants.It is possible to simplify the production of hybrid seed by using a round-seeded female parent and a prickly-seeded male parent. Moreover this will prevent errors: all plants can then be harvested and threshed at the same time and in cleaning the prickly seed can be separated mechanically from the round-seeded commercial seed. The use of a prickly-seeded male parent will be an extra check on the possible growing of later generations by others.     

Influence of pre-harvest ozone exposure on quality of strawberry fruit under simulated retail conditions

Strawberries (Fragaria × ananassa Duch.) were grown under an ozone-enriched atmosphere, and fruit yield, quality, and postharvest behavior under simulated retail storage conditions were investigated. The more ozone sensitive cv. Korona and the less sensitive cv. Elsanta, according to previous studies, were exposed for 2 months to 156 μg m⁻³ ozone on average, or air without ozone, in controlled-environment chambers. The influence of ozone depended significantly on the cultivar and its susceptibility to oxidative stress. Generally, ozone decreased the contents of ascorbic acid, caused higher lipid peroxidation and lowered sweetness of the fruit. In the case of lipid peroxidation, the effect was strengthened under retail conditions. The ozone stress did not influence yield, size, antioxidative capacity, anthocyanins, or phenolic compounds of fruit. In the more sensitive cv. Elsanta, ozone-induced sepal injuries were detected and the appearance of fruit was thus impaired; glutathione content of fruit also decreased. In contrast, fruit quality of the less sensitive cv. Korona remained almost constant. In general, retail conditions impaired quality of strawberry fruit and in the case of an effect on quality by ozone during fruit development, quality was slightly worse after storage due to the high perishability of the strawberry fruit.     

不同类型品种对春玉米产量、品质的影响

通过对不同类型玉米品种间籽粒品质、产量差异的研究，表明品种的遗传特性是造成不同类型玉米品种间品质差异的主要原因，不同类型玉米品种的粗蛋白、粗脂肪、粗淀粉、赖氨酸含量、籽粒容重及其产量差异达显著水平，目前陇东旱塬区应以推广种植普通玉米为主。     

授权品种的委托代繁和转许可——兼对诉侵犯品种权纠纷一案证据评析

品种权人对其授权品种,享有排他的独占权。被许可人以委托代理的方式授权他人生产、销售或使用授权品种繁殖材料的,属于转许可。未经品种权人许可,被许可人委托代繁或委托代销授权品种繁殖材料的,都是对品种权的侵犯。     

玉米杂交种制种技术总结

为了适应种子产业市场化发展需求,满足大田生产用种,扭转玉米籽种多年依赖外调且种源难以保证的被动局面,保障市场供给和农民用种安全.从1999-2002年,在山西省安泽县和川镇进行了为期三年玉米制种技术的探索,并取得一定经验.     

不同熟性棉花品种冠层温度分布特点

[目的]明确不同类型棉花品种冠层温度的分布特点,探究冠层温度与光合特性之间的关系,寻求判断棉花熟性的可能指标.[方法]选择6个常用的供试棉花品种,利用搭载热红外测温仪的无人机获取棉花花铃期冠层温度的数字图像,同时测定同一时间段的蒸腾速率、气孔导度等光合指标.[结果]中棉所50不同部位气冠温差表现为上层>下层>中层,中棉...