Canola Genotypes Research Articles

Impact of Salinity Levels and Varietal Differences on some Growth Characters, Yield and Yield Attributes of Canola Genotypes

Impact of Salinity Levels and Varietal Differences on some Growth Characters, Yield and Yield Attributes of Canola Genotypes

Genetic variation for leaf carbon isotope discrimination and its association with transpiration efficiency in canola (Brassica napus).

Drought is a major constraint to canola production around the world. There is potential for improving crop performance in dry environments by selecting for transpiration efficiency (TE). In this work we investigated TE by studying its genetic association with carbon isotope discrimination (Δ) and other traits, e.g. specific leaf weight (SLW) and leaf chlorophyll content (SPAD). Among the 106 canola genotypes - including open-pollinated, hybrid, inbred types and cytoplasmic variants - tested in the field and glasshouse there was significant genotypic variation for TE, Δ, plant total dry weight, SLW and SPAD. Strong negative correlations were observed between TE and Δ (-0.52 to -0.76). Negative correlations between Δ and SLW or SPAD (-0.43 to -0.78) and smaller but significant positive correlations between TE and SLW or SPAD (0.23 to 0.30) suggested that photosynthetic capacity was, in part, underpinning the variation in TE. A cytoplasmic contribution to genetic variation in TE or Δ in canola was also observed with Triazine tolerant types having low TE and high Δ. This study showed that Δ has great potential for selecting canola germplasm with improved TE.

Effects of Sowing Date and Chitosan on Some Characters of Canola (Brassica napus L.) Genotypes

Changes in the environment that are associated with different sowing dates can be expected to alter canola (Brassica napus L.) growth and development. The objective of this work was to study the effect of sowing date and chitosan on some characters of canola genotypes. Five genotypes (RGS003, Sarigol, Zafar, Dalgan, and Julius) were sown in three sowing dates (October 7, 17, and 27), for two years (2014–2015 and 2015–2016). A factorial split-plot experiment was conducted in a complete randomized blocks design with three replications, where the sowing dates and the two levels of chitosan (0 [control] and 0.2% concentrations) were allotted to main plots and the genotypes were allotted to subplots. The ANOVA revealed that the main effects of sowing date, chitosan and genotype were significant for almost all measured characters. In addition, the interaction effect of sowing date and genotype was significant for plant height, number of silique in shoots, number of seeds per main silique, 1000-seed weight and oil yield. The seed and oil yields in the third sowing date were reduced by 0.46 and 0.49%, respectively, compared to the first sowing date. The results of the present study indicated that early sowing date and chitosan application had positive effects on the measured characters. Cluster analysis divided the cultivars into two groups. Also, the PCA revealed that the three first PC confirmed about 98% of the total variance among the studied genotypes.

Genetic Variability and association of some quantitative characters and protein fingerprinting in some canola genotypes

Genetic Variability and association of some quantitative characters and protein fingerprinting in some canola genotypes

Analysis of Genetic Diversity among a Population of Canola Genotypes As Reveled By ISSR-PCR and Their Associations to Seed Yield and Oil Content

Analysis of Genetic Diversity among a Population of Canola Genotypes As Reveled By ISSR-PCR and Their Associations to Seed Yield and Oil Content

Effect of Temperature Regimes on Morphological Development of Selected Canola (Brassica napus) Genotypes

Seven canola genotypes selected from early and mid-maturing groups of canola genotypes presently planted in the Western Cape canola production area were grown in 3 litre plastic bags filled with a mixture of sand and compost at ratio of 1:1 and irrigated with fully balanced nutrient solution at EC=2.0 in two glasshouses at night/day temperature regimes of 10/15˚C and 15/20˚C. Plant heights were measured at 14 days interval from 28 to 84 days after planting (DAP). Plants were sampled for leaf area (LA) and above ground dry mass (DM) at budding, flowering and seed physiological maturity stages. Plant growth rates (PGR) from planting to budding, from budding to flowering and from flowering to physiological maturity growth stages were calculated. Relative growth rates (RGR) and net assimilation rates (NAR) from budding to flowering and from flowering to physiological maturity stages were also calculated. Days after planting, GDD and PTU at budding, flowering and physiological maturity were correlated with leaf area, dry mass, number of pods plant-1 and pod dry mass plant-1 at budding, flowering and physiological maturity stages to determine whether there were relationships between the variables. The study showed that by increasing night/day temperature from 10/15˚C to 15/20˚C plant height, number of leaves plant-1 at budding stage, leaf area at budding , plant growth rate (PGR) from planting to budding stage and relative growth rate (RGR) from budding to flowering stage were increased. However, PGR from budding to physiological maturity, RGR from flowering to physiological maturity, net assimilation rate (NAR) from budding to flowering stage, leaf area at flowering and physiological maturity stages, as well as number of flower stems, number of pods plant-1, above ground total dry mass at flowering and physiological maturity stages were decreased. Pod dry mass at physiological maturity decreased by 22.24% to 40.35% for different genotypes which clearly demonstrated the variations in sensitivity of canola genotypes to increasing night/day temperatures and also indicates that canola crop can be genetically improved for heat tolerance.

Combining ability and heterosis for some canola characteristics sown on recommended and late planting dates using biplot

Canola (Brassica napus L.) is one of the most efficient oil-producing crops in arid and semi-arid regions of the world. In the current study, ten winter canola genotypes [seven genotypes as lines (Zarfam (L1), Talaye (L2), SLM046 (L3), Geronimo (L4), Modena (L5), Opera (L6) and Symbol (L7)] and three genotypes as testers [Okapi (T1), Licord (T2) and Orient (T3)] and their F1 hybrids (21 hybrids) were evaluated to determine the genetic parameters for grain yield, oil content, meal and seed glucosinolate contents under two different planting date [recommended (late September) and late planting (late October)]. According to combined analysis of variance there were significant differences among the genotypes for most studied traits. The genotype main effect and genotype × environment interaction (GGE) biplot method was used for analyzing line × tester design data. Among the lines, L5 showed high negative general combining ability (GCA) effect for meal glucosinolate content in both conditions whereas L1, L5 and L6 revealed high negative GCA effects for seed glucosinolate content in both planting date. From the results, it could be concluded that, hybridization between T1×L1, T1×L6 or T3×L5 is an efficient approach to release genotypes with low seed and meal glucosinolate content. Furthermore, to develop canola cultivars with higher seed and oil yield, hybridization between T1×L7 or T2×L7 is highly recommended. Improved oil content will be achieved if T1×L5, T2×L5 or T3×L6 hybrids are implemented into the breeding programs.

Effect of seed rates on yield and oil components of canola genotypes

Effect of seed rates on yield and oil components of canola genotypes

Seed Yield and Water Productivity of Irrigated Winter Canola (Brassica napus L.) under Semiarid Climate and High Elevation

Canola is a cash crop produced for its highly-valued seed, and as a protein source for animal feed. While winter canola is produced mainly in the high plains, it is expanding to new environments, and is greatly incorporated into crop systems with advantages in terms of increasing crop yield and improving soil health. The objectives of this study were to evaluate eight winter canola genotypes for seed yield, and to determine their water productivity under semiarid climates and high elevations in the Four Corners region at Farmington, New Mexico. A field experiment was conducted at the New Mexico State Agricultural Science Center at Farmington for five growing seasons. Eight genotypes of winter canola (Baldur, Flash, Safran, Sitro, Virginia, Visby, Wichita, and Sumner) were arranged into the randomized complete block design. The field was fully irrigated with a center pivot irrigation system. Results showed that winter canola seed yield was dependent on genotype, varying from 2393 to 5717 kg/ha. The highest yield was achieved by Sitro, and the lowest yield by Sumner. There was inter-annual variation in canola nitrogen-use efficiency (NUE), irrigation water-use efficiency (IWUE), and crop water-use efficiency (CWUE). NUE varied from 12.9 to 50.4 kg seed/kg N, with the highest NUE achieved by Sitro, and the lowest by Sumner. IWUE varied from 0.34 to 0.80 kg/m3, and canola CWUE from 0.28 to 0.69 kg/m3. The highest water productivity was achieved by Sitro. The results of this study showed full assessment of canola production under the semiarid climate in the Four Corners region, and could improve crop productivity and profitability.

Rapid detection of Leptosphaeria maculans avirulence gene AvrLm4-7 conferring the avirulence/virulence specificity on Brassica napus using a tetra-primer ARMS-PCR

Leptosphaeria maculans is the causal agent of blackleg disease in canola (Brassica napus), resulting in significant yield loss in canola fields worldwide. AvrLm4-7 is an avirulence effector gene in L. maculans, and a single nucleotide mutation at codon 358 is responsible for the absence of the AvrLm4 allele. A tetra-primer amplification refractory mutation system-PCR assay (ARMS-PCR) was developed to rapidly differentiate the AvrLm4AvrLm7 and avrLm4AvrLm7 genes of L. maculans isolates, which differ by a single point mutation. By this approach, we were able to amplify distinct PCR products to infer the gene of the tested isolates. These results were also confirmed through phenotyping, using the cotyledon inoculation test and two canola genotypes with the corresponding resistance genes. The tetra-primer ARMS-PCR assay developed in this study is a simple, rapid, and useful protocol to identify the AvrLm4-7 alleles in L. maculans isolates. This assay has potential applications in the selection of resistant canola cultivars as part of broader antifungal strategies.

Effect of branch position on seed weight and oil content in canola ( Brassica napus L.)

Increasing seed weight and oil content are the main pathways to increase canola seed oil yield. The effect of branch position on seed weight and oil content has not been previously reported in canola. Field experiments were conducted to explore the impact of branch position on seed weight and oil content. Four canola genotypes, Zheyou 50, Zhongshuang 11, Zheyou 18, and Zheshuang 8, were used to evaluate seed weight, oil content, carbohydrate profile, and nitrogen content in the main inflorescence and branches from the top to the bottom of the main stem. Seed weight and oil content decreased from the main inflorescence to the lower branches in the four genotypes. Lower carbohydrate and nitrogen content in the seed and low transport efficiency of the two chemical compounds in the silique and branches were responsible for the lower seed weight and oil content in Zheshuang 8 and Zheyou 18, respectively. However, the decreasing seed weight and oil content in the branches did not correspond with decreasing carbohydrate and nitrogen content in the branches from the top to the bottom. The result suggested complex carbohydrate and nitrogen metabolism in the canola seed in the different branches.

Devolopment of Some Canola Genotypes to Salinity Tolerance Using Tissue Culture Technique

T HIS WORK was carried out during 2011- 2015 in the laboratories of Cell Research Department (CRD), Field Crops Research Institute (FCRI), Agricultural Research Center (ARC), Giza, as well as, in the greenhouse of Agronomy Department, Faculty of Agriculture, Ain Shams University, Egypt, to study the variation among canola varieties in response to salt tolerance through tissue culture propagation. This work was aimed to establish a regeneration protocol for canola genotypes, production of salt-tolerance plants through selection of salt-tolerance callus via somaclonal variation and subsequent regeneration of plantlets from such callus. Four genotypes of canola were used for establishment a regeneration protocol, Bingo and Torpe were uesed as highly salt tolerant genotypes while, Conny and Siberian as susceptible genotypes. The results indicated that MS medium supplemented with 2 mg/l 2,4-D was the successive medium for callus formation and shoot regeneration was obtained from MS medium supplemented with 5 mg/l BA + 0.05 NAA, while, 1mg/l IBA was the better growth regulator for rooting.For in vitro selection of salt tolerant calli, Torpe (genotype overcomes the others in calli survival percentages under 8000, 12000 and 16000 ppm NaCl concentrations. The results of shoot frequency from tolerant calli cleared that Torpe genotype recorded the highest value of shoot percentage followed by Bingo genotype, whereas, Conny followed by Siberian genotypes were recorded the lowest values. At 16000 ppm NaCl concentration, only tolerant calli of Torpe genotype was able to initiat shoot under this concentration. For acclamatization after regeneration from the tolerant calli, only five salt tolerant plantlets developed from Torpe genotype and eight salt tolerant plantlets developed from Siberian genotype that succeeded to complete their life cycle and reached maturity stage and produced seeds. These regenerated genotypes were referred as T1, T2, T3, T4 and T5, the five regenerated plants developed from Torpe genotype that tolerate NaCl concentration up to 16000 ppm, as well as, S1, S2, S3, S4, S5, S6, S7 and S8, the eight regenerated plants developed from Siberian genotype that tolerate NaCl concentration up to 12000 ppm.

ASSESSMENT OF GENETIC DIVERSITY OF SOME CANOLA GENOTYPES

Analyzed of genetic diversity for six canola genotypes using 5 inter-simple sequence repeats (ISSR) primer pairs were done. The cluster results of UPGMA method indicated that all the genotypes could be distinguished by ISSR markers. Six genotypes were categorized into two main clusters. Cluster I comprised Egyptian genotypes Serw-6 and Serw-4 and German genotype AD 201/Gi/81. Genotypes within cluster II comprised of French (Pactol), Chinese (Wan-you 25) and German (RG 4514).

Assessment of canola crop lodging under elevated temperatures for adaptation to climate change

With temperatures rising due to global climate change, many endeavors have been looking into how this will affect crop production and food security. Lodging, which is the permanent displacement of crop plants from upright position, is one of the main causes of yield loss and quality reduction in canola/oilseed rape. However, there has been little research to date on how the mechanisms of crop lodging might be affected by high temperature. The objectives of this study were to examine the effect of high temperature on the structural features of lodging resistance in four canola genotypes, to determine what kind of lodging (stem or root) was more prevalent, and to identify corresponding mechanistic traits associated with lodging under high temperature conditions. The experiment was carried out in controlled growth facilities with the genotypes tested under normal (23/17°C; CK) and high temperature (27.01/24.3°C) regimes. The results showed that high temperature reduced root lodging resistance significantly, as indicated by a dramatic reduction in both root anchorage and safety factor (against anchorage failure). These were attributable to the large suppression on lateral root growth (32%), and thereby reduction in root bending resistance (33%), root–soil cone dimension (13%), and its shear strength (33%). High temperature showed an inconsistent effect on stem lodging resistance, which was in alignment with the engineering mechanics theory and supported by the anatomical observations. These results indicated that canola genotypes were more prone to anchorage failure than stem buckling. Consequently, root lodging resulted from anchorage failure would become a critical aspect under rising temperatures with the global warming. The present study indicates that root lodging should be targeted as a priority to improve crop lodging resistance through breeding selection for a root system with high anchorage strength, especially when the crop plants are expected to encounter inevitable high temperature stress.

English

The aim of this study was to evaluate the agronomic performance and oil content of 13 canola genotypes in Western Paraná, Brazil. The experiment was carried out, during the year of 2015, in the municipality of Marechal Cândido Rôndon in the west of the State of Paraná. A Randomized Complete Block Design (RCBD) was utilized with four replications. The genotypes of canola evaluated were Hyola 401, Hyola 76, Hyola 61, Hyola 433, Hyola 50, Hyola 571CL, Hyola 575CL, Hyola 474CL, Hyola 555TT, Hyola 656TT, Hyola 559TT, W8006, and H92002. Sowing was done in plots with four rows, spaced at 0.45 and 5 m in length, on May 8, 2015. The evaluated parameter were phenology, plant height, number of pods per plant, grains per pod, weight of thousand grains, grain yield and oil content. Significant differences were observed where the genotype of canola Hyola 401 and Hyola 559TT reached the physiological maturation in 129 days. No significant differences were observed in the variables analyzed by the Tukey test at 5% probability except the mass of thousand grains in which the Hyola 76 genotype performed better, with 4.11 grams. The average grain yield of tested genotypes was 1518.14 kg ha-1 and the average of grain oil content was 42.45%.   Key words:  Adaptability, Brassica napus, grain yield, Hyola.

Virulence and inoculum density‐dependent interactions between clubroot resistant canola (Brassica napus) and Plasmodiophora brassicae

To mitigate the impact and dissemination of clubroot in western Canada, canola (Brassica napus) producers have relied on clubroot resistance traits. However, in 2013 and 2014, new strains of the clubroot pathogen, Plasmodiophora brassicae, emerged that are virulent on most clubroot‐resistant (CR) canola genotypes. Novel strains of the pathogen were inoculated onto two susceptible canola cultivars, one resistant line and six CR cultivars. Although all cultivars/lines showed a susceptible response to inoculation with the new strains of P. brassicae, the severity of disease reaction, root hair infection rates and the amount of P. brassicae DNA present in each canola genotype varied depending on the strain. In addition, the effect of inoculum density on disease severity and gall formation was recorded for one of these new strains on a universally susceptible Chinese cabbage cultivar and one susceptible and 10 resistant canola genotypes. Although root galls were observed at an inoculum density of 103 spores per mL of soil, clear differentiation of susceptible and resistant reactions among canola cultivars/lines was not observed until the inoculum density reached 105 spores mL−1. At a spore density of 106 spores mL−1 and above, all cultivars/lines developed susceptible reactions, although there was some differentiation in the degree of reaction. This study shows the potential to develop a unique disease profile for emergent clubroot pathotypes and shows a useful range of spore densities at which to study new P. brassicae strains.

Quantification of the impacts of climate warming and crop management on canola phenology in Punjab, Pakistan

AbstractYield is influenced by the length of the growing season, which is affected by weather conditions and management practices of a crop, including sowing dates and shifting of cultivars. It is necessary to understand the effects of agronomic management practices and weather variables on phenological stages and crop phases in order to develop strategies for adaptation of agricultural systems to changes in climatic conditions. The goal of this study was to determine the impact of warming trends on phenology of canola from 1980 to 2014 for central and southern Punjab, Pakistan. Sowing, emergence, anthesis and physiological maturity dates were delayed by an average of 6.02, 3.14, 3.31 and 1.89 days per decade, respectively. The duration of sowing to anthesis, sowing to physiological maturity and anthesis to physiological maturity phases decreased an average 2.71, 4.13 and 1.42 days per decade, respectively, for all 10 locations that were analysed in this study. The sowing, emergence, anthesis and physiological maturity dates were positively correlated with an increase in temperature by an average 2.71, 1.41, 1.49 and 0.85 days per °C, respectively. However, the phenological phases such as sowing to anthesis, anthesis to maturity and sowing to maturity were negatively correlated with an increase in temperature by an average of 1.22, 0.64 and 1.86 days per °C, respectively, for all 10 locations. Applying a process‐based CSM‐CROPGRO‐Canola model using a standard cultivar (field tested) for all locations and years indicated that the simulated phenological stages occurred earlier due to the warming trend compared to the observed phenological stages. One‐quarter of the negative effects of this thermal trend was compensated by growing new cultivars that had higher thermal time requirements. Therefore, new canola genotypes with a higher number of growing degree day requirement and high temperature tolerance should be a priority for evolving new cultivars.

Pod drop in Brassica napus is linked to weight-adjusted pod-retention resistance

Canola (Brassica napus L.) often experiences high seed losses prior to and during harvest operations. Pod drop and pod shatter are responsible for pre-harvest seed losses in canola although relatively little is known about the significance of pod drop to total pre-harvest seed losses in canola. This research describes a method to measure the predisposition for pod drop among canola genotypes that was developed and tested across different sites from 2013 to 2015. This method, referred to as pod-retention resistance, consists of the use of a force gauge to quantify the force required to break the pod pedicle at the pedicle-rachis junction. Two sets of field experiments were used, the first developed and modeled the factors that influence pod-retention resistance, pod drop and seed shatter. A second set of experiments was used to validate these findings on a broader range of genotypes and determine whether a relationship between pod retention resistance and pod drop could be determined. Results showed that the pod-retention resistance was significantly greater for pods on the proximal half of the rachis compared to the distal half of the rachis. Several factors contributed strongly to variation in pod retention resistance (rachis position, genotype and site) and pod drop (site, rachis position and genotype). The relative importance of individual factors varied between pod retention resistance and pod drop suggesting no relationship between the two. However, weight-adjusted pod retention resistance, i.e., average pod retention resistance corrected for the average weight of dropped pods, was strongly correlated with pod drop, particularly in the validation experiments. This method could be used by canola breeders to select for and develop genotypes with reduced predisposition for seed losses via pod drop.

Univariate Stability Analysis of Genotype×Environment Interaction of Oilseed Rape Seed Yield

Thirteen stability statistics were used to analyze genotype × environment (GE) interaction of 36 canola genotypes. Combined analysis of variance indicated that GE interaction significantly influenced seed yield performance. According to Type I stability concept (environmental variance, coefficient of variation and stability variance) genotypes G7, G9 and G13 were the most stable genotypes, while based on the Type II concept (coefficients of three linear regres­sion models), genotypes G33, G27 and G29 could be selected as the most favorable genotypes. Also, genotype G7 was the most favorable genotype according to Type III stability concept (deviation from linear regression method). Genotypes clustering based on stability properties and mean yield grouped them into three distinct classes. Coefficient of determination for the canola genotypes indicated that genotypes G27 and G33 were the most stable genotypes but the genotypes G1, G10 and G25 had the highest desirability index and were the most stable ones. The plot of principal component analysis was used for graphic display of the relationships among statistics and the first axis distinguished the Type II of stability concept from other types and mean yield groups near this stability type. However, based on most statistics and mean yield performance, genotypes G9 or Fanaei‑6 (2592.47 kg ha‑1), G11 or Fanaei‑14 (2592.47 kg ha−1), G12 Fanaei‑15 or (2592.47 kg ha‑1) and G19 or Dez‑7169 (2592.47 kg ha‑1) were the most stable and favorable genotypes and are recommended for national release Iran.

Phosphorus Use Efficiency in Canola Genotypes

Phosphorus (P) deficiency is a widespread macronutrient deficiency and is one of the major constraints limiting canola production. Efficient P fertilizer method’s is important for economic production of canola and sustaining of environmental quality. The aim of this research is to investigate P use efficiency (PUE) of canola genotypes at an early growth stage. The experiment was set up as a completely randomized design in a factorial scheme. The factors were ten canola genotypes (Excalibur, Nelson, Vectra, Orkan, Triangel, TKK08-5, Oase, Elvis, Es Hydromel and Licord) and three P rates (0, 50 and 100 mg kg-1). The plant parameters, dry weight of shoot and root varies significantly with P levels in all applications. In general, P concentrations and dry weight of the genotypes are linearly raised by P treatments. The genotype Elvis produced significantly higher shoot dry matter 9.24 g pot-1 at 100 mg kg-1 P rate compared to the other applications. However, without P, dry matter (DM) of genotypes varied between 1.67 to 6.96 g pot-1. Cultivars classified as efficient responsive are: Elvis, inefficient responsive: Nelson, Orkan, Oase, Licord, and efficient nonresponsive: Excalibur, Vectra, Triangel, TKK08-5, Es Hydromel. Plant dry matter can be used for identification of the genotypes which could be adapted to low or high soil P availability conditions at an early growth stage. Nutrient use efficiency and genotypic differences in plants should be considered in order to create an accurate and a balanced fertilizer program as well as improving crop yield in agricultural production system.