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111.
Gert Aamand Pedersen Lars Gjøl Christensen Poul H. Petersen 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):26-31
Abstract The relationship between twice the adjusted daughter yield deviation (DYD) of the son and the average of the estimated breeding values (EBV) of his parents was investigated for milk and fat yield. Deviations from expectations of DYD minus the pedigree index and the regression of DYD on the EBV for each of the parents were estimated. The EBV of each bull dam was calculated in several ways using different combinations of pedigree information and their own records. In all, 1693 bulls (880 Black and White (BW), 418 Red Danish (RD) and 395 Danish Jersey (DJ)) with Direct Updating indices for milk and fat yield were included in the investigation. Mean discrepancies between estimated and observed genetic merit for kg of milk yield were ?348 for BW, ?213 for RD and ?228 for DJ, when all of the bull dams' individual records were utilized in breeding value estimation. The corresponding mean discrepancies for kg of fat yield were ?14.7, ?11.5 and ?11.9, respectively. The discrepancies were positively correlated with the number of lactation records included in the dams' EBVs. Regression coefficients of bull DYDs on bull dam breeding values were significantly lower than expected for RD and BW regardless of the number of individual lactation records included in the dams' indexes for milk and fat yield. For all three breeds, the regression coefficients were lowest for fat yield. The most probable cause of overestimation in bull dam EBVs is preferential treatment, particularly in second and later lactations. To avoid this bias, estimation of a bull dam's breeding value should be based on pedigree information and on records from only her first lactation. 相似文献
112.
A study was conducted to evaluate the macro and trace mineral contents of ten enset varieties collected from Sidama zone of
southern Ethiopia. Samples of leaf lamina, leaf midrib, pseudostem and corm were taken from ten enset varieties at the age
of 5 to 6 years during the main rainy season. The dry weight of each variety and fraction were also determined. Mineral contents
in fractions of different enset varieties were analysed and compared with nutrient requirements of ruminants. The contribution
of different enset fractions to the total dry weight was variable (P < 0.05), the highest being from pseudostem and the lowest
from leaf lamina. There were varietal differences (P < 0.05) in macro and trace mineral content in different fractions except
phosphorus (P) content of leaf lamina. Most enset fractions were rich sources of major minerals such as P, potassium (K),
calcium (Ca) (except corm) and magnesium (Mg). Sodium (Na) content was very low. Most fractions were rich in iron (Fe) and
manganese (Mn), but deficient in copper (Cu), except leaf lamina. Zinc (Zn) content was high in corm, but low in other fractions.
This account of the macro and trace mineral content of different enset varieties and fractions could help in strategic supplementation
intended to alleviate mineral deficiencies. 相似文献
113.
RAPD genetic diversity of Albanian olive germplasm and its relationships with other Mediterranean countries 总被引:4,自引:0,他引:4
Angjelina Belaj Zlatko Satovic Hajri Ismaili Dhimitër Panajoti Luis Rallo Isabel Trujillo 《Euphytica》2003,130(3):387-395
RAPD markers were used for the study of 19Albanian olive cultivars and two wild olives (oleasters). A total of 76polymorphic
bands (4.8 polymorphic markers per primer) out of 107 reproducible were obtained using 16 primers. The number of bands per
primer ranged from 4 to 10,whereas the number of polymorphic bands ranged from 1 to 9, corresponding to 71%of the total amplification
products. All the accessions could be identified by the combination of four primers: OPA-19;OPA-02; OPK-16 and OPP-19. The
dendrogram,based on Jaccard's index, included three major groups according to their origin: 1)most of the cultivars from the
area of Berat (South of Albania) 2) cultivars from the Centre and Centre-North of Albania and3) cultivars from the Centre
and North-West of Albania along with the oleaster from Elbasan. In order to evaluate the origin of Albanian cultivars they
were compared to those diffused in other countries like Greece, Italy and Turkey, due to geographical and historical affinity
among these countries, by using a one way AMOVA. Although most of the genetic diversity was attributable to differences among
cultivars within each country (91.47%) significantφ-values among countries(φst = 0.085; p < 0.001)suggested the existence of RAPD phenotypic differentiation. Significant φ-values in all pairs formed by Albania with
the other countries were observed. These results are consistent with the autochthonous origin of Albanian cultivars.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
114.
Sclerotinia sclerotiorum infections on sunflower capitula produce white rot, one of the most dangerous diseases sunflower bears in all humid areas.
Therefore, disease quantification on developed genetic materials is a very important action in sunflower breeding. Given the
horizontal type of resistance these evaluations should be made in different environments. Several hybrids obtained after crossing
seven female × seven male sunflower inbred lines in a factorial mating design were evaluated for resistance to white rot in
two locations in the southeast of the province of Buenos Aires, Argentina. Disease incidence and the symptom appearance index
indicated significant genotypic effects and genotype × environment (G × E) interactions. Genotypic effects were a greater
source of variance than the G × E interaction effects. The G × E interactions only represented changes in magnitude. These
results were used to identify the best genotypes for both resistance factors. Four hybrids showed low disease incidence values
under both artificial and natural infections, of which only two had high values of the symptom appearance index at both locations.
These hybrids are considered to have adequate resistance attributes for the ascosporic penetration and the mycelium extension
in the capitulum tissue and could therefore be sown in the province of Buenos Aires without increasing risks of S. sclerotiorum attacks. 相似文献
115.
116.
117.
O. K. Gondor G. Szalai V. Kovács T. Janda M. Pál 《Journal of Agronomy and Crop Science》2016,202(3):217-230
To find a connection between polyamines and various protective effectors involved in the development of cold tolerance, eight different cereal genotypes, including wheat, barley and oat species, were investigated during the acclimation phase to low temperature. Exposure to low temperature induced different changes in the levels of polyamines, and other signalling molecules, such as salicylic acid and abscisic acid, and of other protective compounds, namely flavonols, sugars and antioxidant enzyme activity, and in the lipid composition of certain membrane factions. The most remarkable differences were observed in the oat varieties compared to the other cereal genotypes, which was manifested in the lack of spermidine accumulation and of decrease in trans‐Δ3‐hexadecanoic acid content, in lower initial and not cold‐inducible abscisic acid content and guaiacol peroxidase activity after cold treatment. Correlation analysis revealed that spermidine shows strong positive relationship with flavonols, abscisic acid and ascorbate peroxidase, while was in negative relationship with trans‐Δ3‐hexadecanoic acid. These results suggest that spermidine may have a crucial role in the cold acclimation signalling processes in cereals. 相似文献
118.
The objectives of this study were to optimize RAPD and AFLP techniques in B. catharticus, and to determine the genetic variability of populations and commercial prairie grass cultivars with the aforementioned molecular
markers. Two populations with contrasting morphological characteristics were evaluated from individual and bulked DNA samples
using RAPD markers. Both analyses showed a similar information about inter population variability. Each accession was sampled
by a single leaf bulk of 10 plants. Accession similarities were established with 276 RAPD and 714 AFLP bands using Jaccard
similarity coefficient. The dendrogram of the accessions using RAPD markers showed that they shared high similarity values
(>94%). A similar result was obtained with AFLP markers (similarity values >98%), revealing a narrow genetic basis in the
analyzed accessions. Consequently, molecular characterization of germplasm should be considered in addition to morphological
criteria, to choose the parental genotypes for breeding programs of this forage crop. The AFLP technique was more efficient
to detect DNA polymorphism in our experiments and unique fingerprints were detected for all the accessions. RAPD is a simple
and non expensive technique, suitable to estimate genetic similarity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
119.
The effect of 0, 0.05 or 0.1 mm abscisic acid treatment on chilling tolerance and salicylic acid‐related responses was investigated in young maize seedlings (Zea mays L., hybrid Norma). Although the pre‐treatment of maize seedlings with abscisic acid slightly decreased the chlorophyll content, it also reduced the level of chilling injury caused by 6 days of cold treatment at 5 °C. Under normal growth conditions, increased levels of bound salicylic acid and of bound ortho‐hydroxycinnamic acid were observed in the leaves during abscisic acid treatment. In the roots, abscisic acid did not affect the free and bound salicylic acid levels, but increased the amount of free and bound ortho‐hydroxycinnamic acid. The activity of glutathione‐S‐transferase increased on the 3rd day of abscisic acid treatment, whereas it did not change when followed by cold stress, compared with the control leaves. In the roots, the activities of glutathione reductase, glutathione‐S‐transferase and ascorbate peroxidase increased during the abscisic acid treatment, and those of glutathione‐S‐transferase and ascorbate peroxidase were also stimulated when abscisic acid pre‐treatment was followed by cold stress, compared with the control roots. Our results suggest that an overlap may exist between the abscisic acid‐induced cold acclimation and the salicylic acid‐related stress response. 相似文献
120.
Javier Puntieri Javier Grosfeld Marina Stecconi Cecilia Brion María Marta Azpilicueta Leonardo Gallo Daniel Barthélémy 《Annals of Forest Science》2007,64(8):839-844
Shoot growth and dieback were compared among progenies of nursery-grown seedlings of Nothofagus obliqua belonging to seven progenies of the same provenance (Quila-Quina, Argentina). First-year shoots consisted of one growth unit (GU) and second-year shoots of one or two GUs. The probability of development of two GU was similar for all progenies. Progenies were different in terms of shoot size, terminal bud abscission, the extent of shoot dieback after shoot extension and the node of origin of the relay shoot on the first shoot. Plants with a second-year shoot consisting of two GUs had a thicker stem and more nodes than those with single-GU shoots. The selection of N. obliqua seed trees based on architectural traits suitable for forestry development at specific sites must contemplate variability among progenies and their probabilities of successful development under different conditions. 相似文献