排序方式： 共有15条查询结果，搜索用时 78 毫秒
1.
A major factor affecting spring canola (Brassica napus) production in Canada is killing frosts during seedling development in the spring and seed maturation in the fall. The objective
of this study was to explore the possibility of producing spring canola lines with mutations that have altered biochemical
pathways that increase cold tolerance. The approach was to generate UV point mutations in cultured microspores followed by
chemical in vitro selection of individual mutant microspores or embryos resulting in measurable alterations to various biochemical
pathways with elevated levels of key defense signaling molecules such as, salicylic acid (SA), p-Fluoro-d,l-Phenyl Alanine (FPA), and jasmonic acid (JA). In addition, since proline (Pro) is known to protect plant tissues in the cold-induced
osmotic stress pathway, mutants that overproduce Pro were selected in vitro by using three Pro analogues: hydroxyproline (HP),
azetidine-2-carboxylate (A2C); and, 3,4-dehydro-d,l-proline (DP). Of the 329 in vitro selected mutant embryos produced, 74 were identified with significant cold tolerance compared
to their donor parents through indoor freezer tests at −6°C, and 19 had better winter field survival than winter canola checks. All chemically selected mutant doubled haploids with increased
cold tolerance compared well with parent lines for all seed quality and agronomic parameters. Development of increased frost
tolerant cultivars should allow for spring canola to be produced in western Canada without compromising seed quality. 相似文献
2.
Cesonienė L Daubaras R Jasutienė I Venclovienė J Miliauskienė I 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(3):238-244
Benzoic acid, total anthocyanins, soluble solids, titratable acidity, and colour properties in juice of the American cranberry
Vaccinium macrocarpon and the European cranberry Vaccinium oxycoccos were investigated. Berry juices of V. macrocarpon cultivars were distinguished by their higher total anthocyanin and benzoic acid amounts. These cultivars accumulated on average
43.11 mg/l of benzoic acid and 92.45 mg/l of total anthocyanins. The levels of benzoic acid and total anthocyanins in V. oxycoccos cultivars were 17.52 mg/l and 42.54 mg/l, respectively. The V. macrocarpon cultivars ‘Franklin’, ‘Le Munyon’, ‘Searles’, and ‘Early Richard’ were selected as the best according to the enhanced total
anthocyanins and benzoic acid amounts. The separation of anthocyanins by HPLC-UV-VIS revealed the presence of six anthocyanins,
with peonidin-3-galactoside being the most prevalent. Galactoside together with glucoside conjugates comprised the largest
percentage of total anthocyanins in the juices of V. macrocarpon and V. oxycoccos cultivars. 相似文献
3.
Henrik Kylin Lennart Torstensson Åsa Ramberg Laima Volkova Peter Sundin 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):243-247
Abstract Six plant protection products (esfenvalerate, diflufenican, isoproturon, terbutylazine, chlorsulphuron, and metsulphuron-methyl) were added to pig and bovine liquid manure, and the degradation of the compounds was followed over a period of 57 &lparlsulphonylureas)(sulphonylureas) or 77 (other compounds) weeks. After 57 weeks more than 50% of the sulphonylureas remained in the bovine liquid manure, while 25% remained in the pig liquid manure. After 77 weeks >90% terbutylazine, 50–60% enfenvalerate, and 10–40% diflufenican and isoproturon had been degraded in both bovine and pig liquid manure. With exception of terbutylazine, the examined plant protection products were neither quickly nor extensively degraded. The practice to add unused spraying liquid or rinse-water containing plant protection products to liquid manure constitutes a risk that unwanted compunds are inadvertently added to the fields when the liquid manure is used as fertilizer, and this may cause crop damage. 相似文献
4.
Cabbage root maggot (Delia radicum) is the most devastating and persistent pest for rutabaga (Brassica napus var. napobrassica) in all production areas in Canada. With the deregistration of terbufos (Counter?) to combat maggot attack, only chlorpyrifos (Lorsban?), an organophosphorous pesticide, remains and extensive use could lead to insecticide resistance. An unprotected crop would
lead to serious domestic and export losses. Root maggot resistance from canola, that originated from the weedy crucifer, Sinapis alba, was transferred to rutabaga by standard hand crossing. A population of doubled haploids was developed from the F1s and screened
in a high pressure root maggot rutabaga production field. Resistant and susceptible isolines were identified from different
crossing groups and these isoline pairs were used to develop a biochemical selection protocol based on HPLC profiles where
glucosinolates can be present as an aid to resistance breeding. Fourteen peaks in the HPLC profile were identified as markers
and predictably varied between the more resistant and more susceptible lines. The 3–4 leaf stage was identified as the ideal
stage for tissue extraction for profiling which is close to the stage when gravid female maggot flies seek host plants for
oviposition utilizing olfactory signals from the host. Olfactory signals for Delia commonly are isothiocyanates which are volatile break down products of glucosinolates. The peaks in the HPLC profiles identified
as markers for resistance contain glucosinolates and may be partially responsible for the plant-insect interaction. A predictive
model is proposed as an aid to breeders for the development of root maggot resistant rutabaga lines. 相似文献
5.
Ivan BALÁŽ Michał BOGDZIEWICZ Sylwia DZIEMIAN-ZWOLAK Carlotta LO PRESTI Aleksandra WRÓBEL Milena ZDUNIAK Rafał ZWOLAK 《Integrative zoology》2023,18(3):440-452
Mast seeding causes strong fluctuations in populations of forest animals. Thus, this phenomenon can be used as a natural experiment to examine how variation in host abundance affects parasite loads. We investigated fleas infesting yellow-necked mice in beech forest after 2 mast and 2 non-mast years. We tested 2 mutually exclusive scenarios: (1) as predicted by classical models of density-dependent transmission, an increase in host density will cause an increase in ectoparasite abundance (defined as the number of parasites per host), versus (2) an increase in host density will cause a decline in flea abundance (“dilution,” which is thought to occur when parasite population growth is slower than that of the host). In addition, we assessed whether masting alters the relationship between host traits (sex and body mass) and flea abundance. We found a hump-shaped relationship between host and flea abundance. Thus, the most basic predictions are too simple to describe ectoparasite dynamics in this system. In addition, masting modified seasonal dynamics of flea abundance, but did not affect the relationship between host traits and flea abundance (individuals with the highest body mass hosted the most fleas; after controlling for body mass, parasite abundance did not vary between sexes). Our results demonstrate that pulses of tree reproduction can indirectly, through changes in host densities, drive patterns of ectoparasite infestation. 相似文献
6.
Laima Česonienė Remigijus Daubaras Vytautas Tamutis Vilma Kaškonienė Paulius Kaškonas Vidas Stakėnas 《Journal of Sustainable Forestry》2013,32(8):791-808
Currently, the aim of modern forest management is not only timber production but also the protection of biodiversity. The initial effects of clear-cut logging on forest understory vegetation, soil and the diversity of litter beetles have been studied. We examined unstudied effects of clear-cutting disturbance on understory vascular plant species abundance, forest soils, and understory vegetation nutrients as well as beetle diversity one year after clear-cutting. Substantial changes in the prominence values and above-ground mass of forest-related vascular plant and moss species were detected. Clear-cuttings resulted in fast appearance of new light-loving plant species. The significant decrease in understory plant biomass influenced the reduction of nutrient pools in clear-cut areas after one year. The clear-cut logging negatively influenced the richness of species and the number of individuals of stenobiontic forest-related beetles in the forest litter. However, forest clear-cuttings were beneficial for eurytopic and open land species. 相似文献
7.
Grape growers may occasionally face difficulties in grape skin coloration and low total soluble solids content in growing of early ripening table grape cultivars. In order to overcome these difficulties, it can be utilized from foliar biostimulants treatments. The purpose of this study, carried out 2015 growing season in Tekirda?, Turkey, was to compare the effects of doses of two different biostimulants, enhancing table grape quality characteristics of cv. Tarsus Beyaz?, cv. Trakya Ilkeren and cv. Yalova Incisi. For this aim, it was focused on three different doses for both biostimulants, including 0, 1750 and 3500?ppm (respectively, Control, BSt A-1 and BSt A-2) for first biostimulant and 0, 3500 and 4500?ppm (respectively, Control, BSt B-1 and BSt B-2) for second biostimulant. As a result, present research demonstrated that BSt B-2 and BSt A-2 treatments especially enhanced most of table grape quality characteristics in cv. Tarsus Beyaz?, cv. Trakya Ilkeren and cv. Yalova Incisi. 相似文献
8.
In the last decade, the cabbage seedpod weevil (Ceutorhynchus obstrictus (Marsham)) has become a major insect pest of canola (Brassica napus L.) in Canada reducing seed yields up to 35%. Therefore, the benefits of developing weevil resistant germplasm to canola
breeders and the industry would reduce input costs, pesticide use, environmental degradation and increase yield. Yellow mustard
(Sinapis alba L.) is resistant to C. obstrictus (CSPW), although the exact mechanism is not known (McCaffrey et al. 1999). A unique canola population was generated at the University of Guelph from a cross between B. napus and S. alba through embryo rescue and backcrossed to canola several times prior to double haploid (DH) production. Approximately one-half
of this DH population had canola quality glucosinolate concentration (<16 μmol/g) and was used for further breeding. The hypothesis
was that some DH progeny from this cross inherited resistance to CSPW from S. alba. Weevil infestation levels were assessed for the B. napus × S. alba BC2 and BC3 DH populations in the field over 7 years in Alberta where weevil pressure is strong to establish the resistant
or susceptible status of these lines. The basic objectives for this study were to confirm field resistance in the B. napus × S. alba germplasm in Ontario and to identify any biochemical markers associated with resistance/susceptibility. Canola doubled haploid
lines derived from BC2 or BC3 families were field screened for resistance (R) followed by chemical analysis of glucosinolates
to detect biochemical polymorphisms correlated with CSPW resistance using High Performance Liquid Chromatography (HPLC). Two
polymorphic peaks were found, one each, from extracts of upper cauline leaves and Stage 3 pod seed, with retention times of
~23 and 19 min, respectively. These HPLC peaks consistently correlated with larval infestation data and the peak differences
between R and S DH lines were significant. Therefore, these two peaks can be considered as biochemical markers in this breeding
germplasm and may play a role in rapid and early detection of CSPW resistance. 相似文献
9.
10.
Des 1980, la résistance aux imides cycliques (I. C.) s'est généralisée dans les populations de Botrytis cinerea sur fraisiers remontants, traités de 3 à 10 fois de juillet à septembre avec des I. C., le taux moyen de fraises présentant des conidies résistantes étant de 72%. Une diminution progressive du taux de résistance est observée après l'arrêt des traitements, mais est suivie d'une forte augmentation 5 à 6 semaines apres la reprise des traitements l'année suivante. L'efficacité des traitements à la vinchlozoline (500 g ha?1) est passée de 94%, pour les essais de 1973 à 1978, à 48% pour ceux établis de 1979 à 1984. Durant cette derniére période, le mélange vinchlozoline (500 g ha?1)+ thirame (1600 g ha?1) a présenté une efficacité de 78% et le tolylfluanide a donné une efficacité de 67%. Sur fraisiers de saison, traités 1 à 6 fois au moment de la floraison, une résistance aux I. C. a été observée en 1980 dans sept des 10 champs analysés, avec un taux moyen de 22%. La résistance ne s'y développe que tardivement et principalement dans les cultures de 2 ans, traitées déjà l'année précédente avec des I. C. Dans les essais, l'efficacité de la vinchlozoline s'est maintenue á 92% entre 1973 et 1984. 相似文献