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[en] Intraspecific hybridization between Triticum petropavlovskyi Udacz. et Migusch., synthetic hexaploid wheat (SHW-DPW), and tetraploid and hexaploid wheat, was performed to collect data on seed set, fertility of F1 hybrid, and meiotic pairing configuration, aiming to evaluate the possible origin of T. petropavlovskyi. Our data showed that (1) seed set of crosses T. petropavlovskyi × T. polonicum and T. petropavlovskyi × T. aestivum cv. Chinese Spring was significantly high; (2) fertility of hybrids T. petropavlovskyi × T. polonicum and T. petropavlovskyi × T. aestivum ssp. yunnanense was higher than that of the other hybrids; (3) fertility of F1 hybrids SHW-DPW × T. dicoccoides and SHW-DPW×T. aestivum ssp. tibetanum was significantly high; and (4) c-value of T. petropavlovskyi × T. polonicum and T. petropavlovskyi × T. aestivum cv. Changning white wheat was also significantly high. The results indicate that the probable origin of T. petropavlovskyi is divergence from a natural cross between T. aestivum and T. polonicum, via either spontaneous introgression or breeding effort.
[en] Root-knot nematodes (Meloidogyne spp.), play a major role in loss of agricultural production. Natural substances, such as salicylic acid (SA) could possibly be involved in inducing host plant resistance against nematodes. The present study is concerned with exploring the effects of varying concentrations of SA as seed priming and soil drench on tomato growth parameters and the reproduction of the root-knot nematode Meloidogyne javanica. SA at 50 μM concentration caused only 2% of juvenile mortality under in vitro conditions. SA applied as 50 μM seed treatment caused 95% and, as a soil drench, 78% reduction in the number of egg masses that formed on tomato plants. The numbers of galls were reduced to a lesser extent. Final nematode density per gram of soil was reduced to less than 1 by the 50 μM SA seed treatment, and in other treatments decreased by between 70 and 88% compared with control plants. Our results indicate SA has potential to lower root knot nematode reproduction in tomato, and seed priming is a fairly easy method to work with. (Author)
[en] One of the problems that occur when working with regression models is regarding the sample size; once the statistical methods used in inferential analyzes are asymptotic if the sample is small the analysis may be compromised because the estimates will be biased. An alternative is to use the bootstrap methodology, which in its non-parametric version does not need to guess or know the probability distribution that generated the original sample. In this work we used a set of soybean yield data and physical and chemical soil properties formed with fewer samples to determine a multiple linear regression model. Bootstrap methods were used for variable selection, identification of influential points and for determination of confidence intervals of the model parameters. The results showed that the bootstrap methods enabled us to select the physical and chemical soil properties, which were significant in the construction of the soybean yield regression model, construct the confidence intervals of the parameters and identify the points that had great influence on the estimated parameters. (Author)
[en] Grape canes are the main agro-wastes from vineyards. This work studied the antioxidant activities of the defatted methanolic extracts (ME) of canes from 11 genotypes: 5 Vitis vinifera widely known cultivars and 6 Chinese wild varieties from three species (V. amurensis, V. davidii, and V. pentagona) and the antioxidant activities of the ME’s chloroform fractions (CF), ethyl acetate fractions (EAF) and water fractions (WF). Among ME and its three fractions, EAF’s total phenolic contents (TPC) and total flavonoid contents (TFC) were the highest, at 586 mg/g of gallic acid equivalent and 320 mg/g of quercetin equivalent, respectively. The antioxidant power of the fractions/extracts was in the order EAF > ME > WF > CF, based on the DPPH radical-scavenging power and ferric-reducing antioxidant activity, while the order was EAF > CF > WF >ME based on the β-carotene-linoleic acid bleaching activity. Methanolic extracts demonstrated the strongest Fe2+-chelating activity. The antioxidant activities of the extracts/fractions generally correlated with the TPC and TFC in all assays, except with the Fe2+-chelating test. Grape canes from V. davidii had the highest TPC, TFC and antioxidant activities compared with those from other grape species. Catechin, epicatechin and trans-resveratrol were the predominant phenolic components of fractions/extracts. In light of these valuable bioactivities, grape canes from annual pruning practice considered as waste material have good commercial potential for utilization as a promising natural antioxidant in the food, pharmaceutical and cosmetic industries, given its low cost and availability in large amounts. (Author)
[en] A total of 72 male lambs of Merina breed were sampled in a 3×2 factorial design, testing three different space allowances treatment (SA) during transport [0.16 m2/animal (SAL; n=24); 0.20 m2/animal (SAM; n=24) and 0.30 m2/animal (SAH; n=24)] and two lairage treatments (TL) during 18 h previous slaughter [fasting (FAST; n=36) vs feeding (FEED; n=36)] on welfare physiological indicators. After transport, glucose and lactate dehydrogenase (LDH) were highest in SAM group and lowest in SAH one (p<0.05). SAL showed intermediate values for both parameters. SA did not affect the rest of the blood parameters studied. TL-FAST treatment decreased glucose values (p<0.001) while increased LDH (p<0.001). Fasting caused an increase (p<0.05) of Red Blood Cell Count values in SAM group. Feed deprivation did not affect cortisol or adrenaline values. Noradrenaline value was higher (p<0.001) in TL-FAST groups than in TL-FEED. In conclusion, under the conditions of this study, a range of space allowance during transport between 0.16 and 0.30 m2/lamb could be recommended without showing major changes on welfare physiological indicators; and feeding could be more appropriate than fasting during lairage. (Author)
[en] Eggplant is a widely cultivated vegetable crop of great economic importance. Its long lasting history of domestication, selection and breeding has led to the development of numerous cultivars with variable traits. In the present study, we assessed the diversity levels within and among eleven Greek and foreign cultivars, using 22 morphological descriptors and two different classes of molecular markers (retrotransposon microsatellite amplified polymorphism-REMAP markers and nuclear microsatellites). Our results, in accordance with other studies in the field showed: a) the limited levels of genetic polymorphism within the cultivars; b) the high morphological and genetic divergence existing among them as indicated by the genetic distance values calculated, which could be attributed to selection, inbreeding and bottleneck effects; and c) the lack of concordance among morphological descriptors and molecular markers. Despite these, our analysis showed that the utilization of combinations of markers is an effective method for the characterization of plant material providing also useful diagnostic tools for the identification and authentication of the selected Greek cultivars.
[en] Drought is a severe threat to maize yield stability in Serbia and other temperate Southeast European countries occurring occasionally but with significant yield losses. The development of resilient genotypes that perform well under drought is one of the main focuses of maize breeding programmes. To test the tolerance of newly developed elite maize inbred lines to drought stress, field trials for grain yield performance and anthesis silk interval (ASI) were set in drought stressed environments in 2011 and 2012. Inbred lines performing well under drought, clustered into a group with short ASI and a smaller group with long ASI, were considered as a potential source for tolerance. The former contained inbreds from different heterotic groups and with a proportion of local germplasm. The latter consisted of genotypes with mixed exotic and Lancaster germplasm, which performed better in more drought-affected environments. Three inbreds were selected for their potential drought tolerance, showing an above-average yield and small ASI in all environments. Association analysis indicated significant correlations between ASI and grain yield and three microsatellites (bnlg1525, bnlg238 and umc1025). Eight alleles were selected for their favourable concurrent effect on yield increase and ASI decrease. The proportion of phenotypic variation explained by the markers varied across environments from 5.7% to 22.4% and from 4.6% to 8.1% for ASI and yield, respectively. The alleles with strongest effect on performance of particular genotypes and their interactions in specific environments were identified by the mean of partial least square interactions analysis indicating potential suitability of the makers for tolerant genotype selection.
[en] This study aimed to develop a remote sensing-based method for forecasting rice yield by considering vegetation greenness conditions during initial and peak greenness stages of the crop; and implemented for “boro” rice in Bangladeshi context. In this research, we used Moderate Resolution Imaging Spectroradiometer (MODIS)-derived two 16-day composite of normalized difference vegetation index (NDVI) images at 250 m spatial resolution acquired during the initial (January 1 to January 16) and peak greenness (March 23/24 to April 6/7 depending on leap year) stages in conjunction with secondary datasets (i.e., boro suitability map, and ground-based information) during 2007-2012 period. The method consisted of two components: (i) developing a model for delineating area under rice cultivation before harvesting; and (ii) forecasting rice yield as a function of NDVI. Our results demonstrated strong agreements between the model (i.e., MODIS-based) and ground-based area estimates during 2010-2012 period, i.e., coefficient of determination (R2); root mean square error (RMSE); and relative error (RE) in between 0.93 to 0.95; 30,519 to 37,451 ha; and ±10% respectively at the 23 district-levels. We also found good agreements between forecasted (i.e., MODIS-based) and ground-based yields during 2010-2012 period (R2 between 0.76 and 0.86; RMSE between 0.21 and 0.29 Mton/ha, and RE between -5.45% and 6.65%) at the 23 district-levels. We believe that our developments of forecasting the boro rice yield would be useful for the decision makers in addressing food security in Bangladesh. (Author)
[en] Dry bean (Phaseolus vulgaris L.) can be a profitable crop for farmers; however controlling weeds effectively without a decrease in yield remains a problem. An example where mechanical weed control is difficult to conduct is dry bean ‘Toscanello’, which is a small sized high-income niche product growing low to the ground. Concerning intra-row weed control, also flame weeding could be an opportunity but the dry bean heat tolerance needs to be studied. The aims of this research were to study the weed control efficacy of a spring-tine harrow and an inter-row cultivator in this bean variety, and to test the tolerance of dry bean cultivated under weed-free conditions to cross-flaming applied with different liquefied petroleum gas (LPG) doses. Flame weeding was applied at BBCH 13 and BBCH 14 bean growth stages by pairs of burners producing direct double flame acting into the intra-row space, with bean plants placed in the middle. The results suggest that the spring-tine harrow used two times at BBCH 13 and 14, respectively, lead to a yield similar to that of the weedy control. The inter-row cultivator could be an opportunity for small-sized dry bean crops producers, enabling them to obtain a similar yield compared to the hand-weeded control. Concerning the bean tolerance to cross-flaming the results showed that bean flamed at BBCH 13 stage had little tolerance to cross-flaming. Bean flamed at BBCH 14 stage was tolerant until an LPG dose of 39 kg/ha, giving yield responses similar to those observed in the non-flamed control. (Author)
[en] The objective of this study was to investigate the variability in cow´s milk somatic cell counts (SCC) depending on the type of milk meter used by dairy farms for official milk recording. The study was performed in 2011 and 2012 in the major cattle area of Spain. In total, 137,846 lactations of Holstein-Friesian cows were analysed at 1,912 farms. A generalised least squares regression model was used for data analysis. The model showed that the milk meter had a substantial effect on the SCC for individual milk samples obtained for official milk recording. The results suggested an overestimation of the SCC in milk samples from farms that had electronic devices in comparison with farms that used portable devices and underestimation when volumetric meters are used. A weak positive correlation was observed between the SCC and the percentage of fat in individual milk samples. The results underline the importance of considering this variable when using SCC data from milk recording in the dairy herd improvement program or in quality milk programs. (Author)