Discriminant analysis for lodging severity classification in wheat using RADARSAT-2 and Sentinel-1 data

Crop lodging - the bending of crop stems from their upright position or the failure of root-soil anchorage systems - is a major yield-reducing factor in wheat and causes deterioration of grain quality. The severity of lodging can be measured by a lodging score (LS)- an index calculated from the crop angle of inclination (CAI) and crop lodged area (LA). LS is difficult and time consuming to measure manually meaning that information on lodging occurrence and severity is limited and sparse. Remote sensing-based estimates of LS can provide more timely, synoptic and reliable information on crop lodging across vast areas. This information could improve estimates of crop yield losses, inform insurance loss adjusters and influence management decisions for subsequent seasons.This research - conducted in the 600 ha wheat sown area in the Bonifiche Ferraresi farm, located in Jolanda di Savoia, Ferrara, Italy - evaluated the performance of RADARSAT-2 and Sentinel-1 data to discriminate and classify lodging severity based on field measured LS. We measured temporal crop status characteristics related to lodging (e.g. lodged area, CAI, crop height) and collected relevant meteorological data (wind speed and rainfall) throughout May-June 2018. These field measurements were used to distinguish healthy (He) wheat from lodged wheat with different degrees of lodging severity (moderate, severe and very severe). We acquired multi-incidence angle (FQ8-27° and FQ21-41°) RADARSAT-2 and Sentinel-1 (40°) images and derived multiple metrics from them to discriminate and classify lodging severity. As a part of our data exploration, we performed a correlation analysis between the image-based metrics and LS. Next, a multi-temporal discriminant analysis approach, including a partial least squares (PLS-DA) method, was developed to classify lodging severities. We used the area under the curve-receiver operating characteristics (AUC-ROC) and confusion matrices to evaluate the accuracy of the PLS-DA classification models.Results show that (1) volume scattering components were highly correlated with LS at low incidence angles while double and surface scattering was more prevalent at high incidence angles; (2) lodging severity was best classified using low incidence angle R-FQ8 data (overall accuracy 72%) and (3) the Sentinel-1 data-based classification model was able to correctly identify 60% of the lodging severity cases in the study site. The results from this first study on classifying lodging severity using satellite-based SAR platforms suggests that SAR-based metrics can capture a substantial proportion of the observed variation in lodging severity, which is important in the context of operational crop lodging assessment in particular, and sustainable agriculture in general

Correlation and path-cofficient analysis of seed yield and yield related trait in Iranian confectionery sunflower populations

This study was undertaken in order to determine the association among yield components and their direct and indirect effects on the seed yield of confectionery sunflower. 36 confectionery sunflower populations originated from different regions of Northwest Iran were characterized using 11 agromorphological traits including: Days to 50% flowering, plant height, stem diameter, head diameter, number of leaves, leaf length, leaf width, petiole length, number of seeds per head, 100-seed weight and seed yield. Phenotypic correlations results show that seed yield per plant was positively and significantly associated with 100-seed weight, head diameter, number of seeds per head, stem diameter and plant height. Path coefficient analysis revealed that number of seed per head, 100-seed weight, and head diameter has positive direct effect on seed yield. Therefore, selection based on these characters would be more effective to improving seed yield in confectionery sunflower in breeding programs.Key words: Helianthus annuus L., direct effect, phenotypic correlation, indirect selection

Allelic polymorphism of 'Makoei' sheep myostatin gene identified by polymerase chain reaction and single strand conformation polymorphism

Myostatin, a transforming growth factor-beta (TGF-) super family member, has been well documented as a negative regulator of muscle growth and development. Myostatin with 376 amino acids is synthesized as a precursor protein. In this study, polymorphism of myostatin gene in Iranian 'Makoei' sheep breeds was investigated by polymerase chain reaction and single strand conformation polymorphism technique (PCR–SSCP). Genomic DNA was isolated from the blood of 92 sheep. A 417 bp myostatin intron 1 segment was amplified by standard PCR, using the locus specific primers. Four different SSCP patterns, representing four different genotypes, were identified. The frequencies of the observed genotypes were , 0.293, 0.130, and 0.163 for AD, AC, AE, and BC, respectively. Allele frequencies were 0.4185, 0.0815, 0.2283, 0.2065 and 0.0652 for A, B, C, D and E. Observed heterozygosity (Hobs) value was 0.7192. The chi-square test showed significant (P<0.05) deviation from Hardy-Weinberg equilibrium for this locus in studied population.Key words: Myostatin gene, polymerase chain reaction (PCR), single strand conformation polymorphism technique (SSCP), Ovis aries

Combined efficacy of silver nanoparticles and commercial antibiotics on different phylogenetic groups of Escherichia coli

NO ABSTRACT AVAILABLESilver nanoparticles (Ag-NPs) can attach to flexible polymeric chains of antibiotics, hence it can be used in combination with antibiotics against resistant bacteria. In this study, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and MBC/MIC ratio of Ag-NPs and antibiotics (gentamicin, tetracycline, erythromycin, ciprofloxacin, nalidixic acid, cefixime, cephalexin, amoxicillin, ampicillin, and penicillin) were quantified against 50 Escherichia coli isolates (25 human urinary tract infection and 25 avian colibacillosis). All isolates had been assigned as four phylogenetic groups A, B1, B2, and D. The results showed that the majority of the human and broiler isolates belonged to phylogenetic groups A and B2. MBC/MIC ratio of Ag-NPs in combination with antibiotics was assessed. It was found that the MIC of the majority of broiler isolates to Ag-NPs was equal to or greater than 50 μg/ml. To conclude, a combination of penicillin and ciprofloxacin with Ag-NPs exhibited profound impact against isolates, the combinations might be applicable for treating multidrug-resistant bacteria

Collection, evaluation and classification of Iranian confectionary sunflower (Helianthus annuus L.) populations using multivaraite statistical techniques

Characterization of confectionary sunflower germplasm resources is critical to their efficient collection and management as well as for breeding programs. Thirty six (36) confectionary sunflower populations originating from different regions of Northwest Iran were characterized using 15 agro-morphological traits. Among the studied traits, high coefficients of variation were observed for harvest index (48.36), seed yield (42.07) and petiole length (41.63). Cluster analysis using Ward's method classified the 36 populations into four groups. A large number of genotypes was placed in cluster III (16 genotypes) followed by cluster I (13), cluster IV (4) and cluster II (3). Clusters I, III and VI include genotypes from different sources indicating no association between clustering pattern and eco-geographical distribution of genotypes. The maximum inter-cluster distance of 9.03 was observed between clusters II and VI indicating the possibility of high heterosis if individuals from these two clusters are cross-bred. Principal component analysis resulted in the first four components with Eigen value greater than one accounting for 78% of the total variation. The results of PCA were closely in line with those of cluster analysis. These results can now be used by breeders to develop high yielding sunflower hybrids.Key words: Cluster analysis, confectionary sunflower, genetic variability, principal component analysis

Molecular characterization and similarity relationships among sunflower (Helianthus annuus L.) inbred lines using some mapped simple sequence repeats

Information about the genetic diversity and relationships among breeding lines and varieties is not only useful for germplasm conservation and inbred line identification, but also for the selection of parental lines for quantitative trait loci (QTL) mapping as well as hybrid breeding in crops, including sunflower. In order to develop mapping populations, genetic distances among twenty eight sunflower genotypes were evaluated using simple sequence repeat (SSR) markers. One hundred and two markers were generated by 38 SSR loci and the mean for the number of allele per locus was 2.32. Polymorphism information content (PIC) values ranged from 0.09 (locus ha3555) to 0.62 (locus ORS598) with an average of 0.41. Jaccard's coefficient similarity matrix for the studied sunflower  genotypes varied from 0.25 to 0.9 indicating a broad genetic base. The maximum similarity (0.9) was observed between genotypes RT931 and ENSAT-R5, while the lowest similarity (0.25) was between genotypes LC1064C and LR64. Based on unweighted pair group method with arithmetic mean (UPGMA) clustering algorithm, the studied genotypes were clustered in four groups. However, some genotypes have the same specific characters that influence their clustering, and as a result, the results of the principal coordinate analysis (PCoA) largely corresponded to those obtained through cluster analysis.Key words: Cluster analysis, genetic diversity, principal coordinate analysis, sunflower, simple sequence repeat

Identification of native fish in Hamedan province (Gamaciyab)

This study was carried out from 2001 to 2002 in Gamasyab River of Hamadan province of Iran in order to identification of indigenous species of this water resource. The main objective of this study was to fish identification for scientific purposes, geographical distribution pattern, preparation atlas of the fishes, introduction of commercial species and awareness on ecological situation of their natural habitats. Also providing necessary information for conservation and sustainable use of these valuable stocks and minimizing environmental impacts of unsecured utilization. Sampling were carried out by selecting 15 sampling stations through the river and fishing by electro fisher and cast net. Identification accomplished by valid identification keys in species level. Photography and slides provides and 10 pieces of each species tagged by unique codes for preservation in national museum. 50 morphometric and meristic characteristics studied for scientific identification.. Indigenous fishes belong to 14 species, 10 genus, 3 family and 2 order. Indeed 2 exotic species belong to Cyprinidae and Salmonidae families recognized. From these indigenous species, 11 belong to Cyprinidae family and only one species belong to Sisoridae family