Canola Genotypes Research Articles

OPTIMIZATION OF MUTAGEN DOSE FOR EARLY SEEDLING YIELD ASSOCIATED QUANTITATIVE CHARACTERS IN CANOLA GERM PLASM

Pakistan is facing vital shortage in supply of health promoting crops used as vegetable as well as oil source. Brassica napus (Canola) is such a rich crop that occupy an important position in the oilseed crops of world but unfortunately in Pakistan its germ plasm needs genetic improvement due to narrow gene pool. Mutagenesis is a powerful tool for introducing new alleles, therefore different doses of Gamma radiations (750Gy, 1000Gy, 1250Gy) and EMS (0.5%, 1.0% and 1.5%) were used to induce genetic diversity for early yield associated quantitative characters in two Canola genotypes (Hyola-41 and Shiralee). The data was recorded for days to flowering, days to maturity, plant height, number of branches per plant and pod length in M2 and M3 generation. Significant (p≤0.05) variations were observed for most of phenotypic parameters for both mutagens. The mean value of all the phenotypic parameters in M2 generation increased with moderate dose of EMS and Gamma rays in both genotypes as compared to respective controls. whereas in M3 generation both genotypes were more responsive to Gamma rays (1000 Gy) for all studied characters except early maturity in both tested genotypes. Heritability analysis exhibited high heritability and high genetic advance for most of the traits by moderate and highest does of Gamma rays, while reverse is true for EMS in both generations for Shiralee.

Clubroot-Induced Changes in the Root and Rhizosphere Microbiome of Susceptible and Resistant Canola.

Clubroot is a soilborne disease of canola (Brassica napus) and other crucifers caused by the obligate parasite Plasmodiophora brassicae. In western Canada, clubroot is usually managed by planting-resistant cultivars, but the emergence of resistance-breaking pathotypes of P. brassicae represents a major threat to sustainable canola production. The rhizosphere and root contain beneficial microorganisms that can improve plant health. In this study, we evaluated the effect of two P. brassicae isolates (termed A and B) with different levels of virulence on the root and rhizosphere microbiomes of clubroot-resistant and clubroot-susceptible canola. Additionally, potential biocontrol microorganisms were identified based on taxa antagonistic to clubroot. Although both P. brassicae isolates were classified as pathotype 3A, isolate A caused a higher disease severity index in the resistant canola genotype compared with isolate B. Metabarcoding analysis indicated a shift in the bacterial and fungal communities in response to inoculation with either field isolate. Root endophytic bacterial and fungal communities responded to changes in inoculation, isolate type, sampling time, and canola genotype. In contrast, fungal communities associated with the rhizosphere exhibited significant differences between sampling times, while bacterial communities associated with the rhizosphere exhibited low variability.

Thiourea improves yield and quality traits of Brassica napus L. by upregulating the antioxidant defense system under high temperature stress

High temperature stress influences plant growth, seed yield, and fatty acid contents by causing oxidative damage. This study investigated the potential of thiourea (TU) to mitigate oxidative stress and restoring seed oil content and quality in canola. The study thoroughly examined three main factors: (i) growth conditions—control and high temperature stress (35 °C); (ii) TU supplementation (1000 mg/L)—including variations like having no TU, water application at the seedling stage, TU application at seedling stage (BBCH Scale-39), water spray at anthesis stage, and TU application at anthesis stage (BBCH Scale-60); (iii) and two canola genotypes, 45S42 and Hiola-401, were studied separately. High temperature stress reduced growth and tissue water content, as plant height and relative water contents were decreased by 26 and 36% in 45S42 and 27 and 42% Hiola-401, respectively, resulting in a substantial decrease in seed yield per plant by 36 and 38% in 45S42 and Hiola-401. Seed oil content and quality parameters were also negatively affected by high temperature stress as seed oil content was reduced by 32 and 35% in 45S42 and Hiola-401. High-temperature stress increased the plant stress indicators like malondialdehyde, H2O2 content, and electrolyte leakage; these indicators were increased in both canola genotypes as compared to control. Interestingly, TU supplementation restored plant performance, enhancing height, relative water content, foliar chlorophyll (SPAD value), and seed yield per plant by 21, 15, 30, and 28% in 45S42; 19, 13, 26, and 21% in Hiola-401, respectively, under high temperature stress as compared to control. In addition, seed quality, seed oil content, linoleic acid, and linolenic acid were improved by 16, 14, and 22% in 45S42, and 16, 11, and 23% in Hiola-401, as compared to control. The most significant improvements in canola seed yield per plant were observed when TU was applied at the anthesis stage. Additionally, the research highlighted that canola genotype 45S42 responded better to TU applications and exhibited greater resilience against high temperature stress compared to genotype Hiola-401. This interesting study revealed that TU supplementation, particularly at the anthesis stage, improved high temperature stress tolerance, seed oil content, and fatty acid profile in two canola genotypes.

Análises de variedades de colza com relação a características quantitativas e qualitativas

Abstract Rapeseed (Brassica napus L.) is one of the most important oil crops in terms of economics, ecology, and nutrition. For the purpose of selecting the most suitable canola genotypes for quantitative and qualitative traits, an experiment was conducted in Damavand region with the presence of nine genotypes and the examination of nine traits with three replications. The results of analysis of variance showed that the effect of genotype in terms of all traits had significant differences at the level of 0.01 and 0.05. Additionally, the results of the average comparison indicated that Zargol and Hyola 401 genotypes were more favorable than other cultivars in terms of all traits. According to the three analyses related to the examination of the traits, it was concluded that the grain yield trait was positively correlated with the harvest index trait, the biological yield trait was positively correlated with the oil percentage trait, and the leaf width trait was positively correlated with the number of days to 50% flowering. Using principal component analysis (PCA), the first three components explained more than 81 percent of the variance in the data, and the first and second components had positive coefficients for Zargol and Hyola 401 genotypes. On the basis of the graphical analysis, the Zargol and Sunday genotypes were selected as the best genotypes. In comparison with the cluster analysis and heat map drawn on the data, the genotypes were grouped into two main groups based on traits. Accordingly, Zargol genotypes are considered stable genotypes in terms of their traits and are suitable for cultivation and agricultural research.

COMBINING ABILITY FOR YIELD, OIL CONTENT, AND PHYSIO-BIOCHEMICAL CHARACTERS OF CANOLA (BRASSICA NAPUS L.) UNDER SALT STRESS CONDITIONS

Creating a half-diallel cross succeeded among seven diverse canola genotypes. The obtained 21 F1 hybrids with their seven parents underwent three salinity stress levels exposure—3.91 dsm1 (Normal), 6.24 dsm-1 (S1), and 7.81 dsm-1 (S2) —during the 2020/2021 growing seasons. Salinity treatments significantly reduced days to 50% flowering, plant height, number of primary branches, pods/plant, 1000-seed weight, seed yield/plant, seed oil content, relative water content, calcium, potassium, and the ratio between K+ and Na+ compared with a normal condition. Proline content, osmotic pressure, and Na+ were considerably higher under salinity stress conditions. Highly significant differences showed among the parents and hybrids for all traits across the tested environments. General (GCA) and specific (SCA) combining ability effects were highly significant for all attributes. The parental genotypes Serw4 and Pactol resulted as good general combiners for increased seed oil content (SOC), seed yield/plant (SYPP), and some of its components in research environments. The hybrid combinations H2/S × Serw4 and Serw4 × Serw6 were good specific combiners for days to first flower (DTF), number of primary branches (NPB), number of pods per plant (NP), a thousand seed weight (TSW), seed yield per plant (SYPP), seed oil content (SOC), proline content (ProC), Ca++, and K+/Na+. The SDS-PAGE analysis of seed proteins indicated high levels of genetic variability and revealed some vital biochemical markers for salt tolerance.

Sustainability on Different Canola (Brassica napus L.) Cultivars by GGE Biplot Graphical Technique in Multi-Environment

Knowledge about the extent of genotype in environment interaction is helpful for farmers and plant breeders. This is because it helps them choose the proper strategies for agricultural management and breeding new cultivars. The main contribution of this paper is to investigate genotype on environmental interaction using the GGE biplot method (Genotype and the Genotype-by-Environment) in ten canola cultivars. The experimental design was a randomized complete block design (RCBD) with three replications to assess the stability of grain yield of ten canola cultivars in five regions of Iran, including Birjand, Karaj, Kashmar, Sanandaj, and Shiraz, within two agricultural years of 2016 and 2017. The results of combined ANOVA illustrated that the effects of the environment, genotype × environment, and genotype were highly significant at 1%. Variance Analysis showed that three environmental impacts, genotype, and interaction of genotype in the environment effect, produced 68.44%, 18.63%, and 12.9% of the total variance. The GGE biplot graphs were constructed using PCA. The first principle component (PC1) explained 65.3%, and the second (PC2) explained 18.8% of the total variation. The research examined polygon diagrams to identify two top genotypes and four mega-environments. Also, the appropriate genotypes for each environment were diagnosed. Using the GGE biplot, it was possible to make visual comparisons and identify superior genotypes in canola. Accordingly,. The results obtained from graphical analysis indicated that Licord, Hyola 401 and Okapi genotypes showed the highest yield and were selected as the most stable genotypes. Also, Karaj region was chosen as a experimental region where the screening of genotypes was very suitable. Based on the ranking of the genotypes in the most suitable region (Karaj), Okapi genotype was selected as the desired genotype. In examining the heatmap drawn between the genotypes and the investigated environments, a lot of similarity between the genotypes of Sarigal, Hyola 401 and Okapi was observed in the investigated environments. The GGE biplot graphs enabled the detection of stable and superior environments and the grouping of cultivars and environments based on grain yield. The results of this research can be used both for extension and for future breeding programs. Our results provide helpful information about the canola genotypes and environments for future breeding programs.

Evaluation of the growth, yield traits and the genetic diversity of some Brassica napus genotypes under Egyptian conditions

BackgroundCanola (Brassica napus L.) is considered an alternate oilseed plant. Therefore, this study aimed to evaluate some growth parameters, yield, chemical parameters and genetic diversity among thirteen canola genotypes including a collection of Chinese, German, French, and local genotypes under Egyptian conditions.ResultTrapper genotype recorded the highest values of plant height (47.12 and 89.75 cm) and dry weight/plant (8.54 and 28.19 dry weight/plant) at 60 and 90 days from sowing, respectively. Data from the field experiments showed that significant differences were recorded among tested genotypes for all yield and its component parameters (i.e., plant height (cm), branches/no. plant, siliquas and seed weight (g/plant) and seed oil %. The genetic diversity and the relationships among the thirteen canola genotypes were evaluated utilizing sequence-related amplified polymorphism (SRAP) and simple-sequence repeats (SSRs) markers. The allelic frequency of the different SRAP and SSR markers tested has differed among the thirteen canola genotypes. The SRAP and SSR analyses showed 659 out of 742 and 15 out of 45 markers, respectively, were detected as polymorphic markers (88.8% and 33.33%) among the tested wheat cultivars In addition, the polymorphism information content (PIC), marker index (MI) and resolving power (RP) parameters were computed to assess the effectiveness of the markers. The results indicated the occurrence of a considerable genetic variation between Chinese, European and Egyptian genotypes.ConclusionThese markers are of considerable value and can be utilized to screen large canola populations. The results of the comparison between the two molecular markers showed that the most effective marker that showed the genetic diversity between canola genotypes was SRAP (88.8%) polymorphism. It could be concluded that the tested canola genotypes could be cultivated under the Egyptian condition with high performance especially Trapper, Agamax and Topas genotypes. Therefore, it could be suggested that these three genotypes seem to be promising for oil gap reduction and need further evaluation for the expansion under new reclaimed regions.

Mesophyll conductance and N allocation co-explained the variation in photosynthesis in two canola genotypes under contrasting nitrogen supply.

The application of nitrogen fertilizer within a normal range has been found to increase the leaf nitrogen content and photosynthetic rate of canola plants (Brassica napus L.). Despite numerous studies on the separate effects of CO2 diffusion limitation and nitrogen allocation trade-off on photosynthetic rate, few have examined both these factors in relation to the photosynthetic rate of canola. In this study, two genotypes of canola with varying leaf nitrogen content were analyzed to determine the impact of nitrogen supply on leaf photosynthesis, mesophyll conductance, and nitrogen partitioning. The results showed that the CO2 assimilation rate (A), mesophyll conductance (g m), and photosynthetic nitrogen content (N psn) increased with an increase in nitrogen supply in both genotypes. The relationship between nitrogen content and A followed a linear-plateau regression, while A had linear relationships with both photosynthetic nitrogen content and g m, indicating that the key to enhancing A is increasing the distribution of leaf nitrogen into the photosynthetic apparatus and g m, rather than just increasing nitrogen content. Under high nitrogen treatment, the genotype (QZ) with high nitrogen content had 50.7% more nitrogen than the other genotype (ZY21), but had similar A, which was primarily due to ZY21's higher photosynthetic nitrogen distribution ratio and stomatal conductance (g sw). On the other hand, QZ showed a higher A than ZY21 under low nitrogen treatment as QZ had higher N psn and g m compared to ZY21. Our results indicate that, in selecting high PNUE rapeseed varieties, it is important to consider the higher photosynthetic nitrogen distribution ratio and CO2 diffusion conductance.

Screening Canola Genotypes for Resistance to Ammonium Toxicity

Soil ammonium toxicity can decrease plant growth, and many crop species have low resistance to ammonium, including canola, an economically important crop. Different genotypes may differ in their resistance to ammonium toxicity, and therefore determining if there are genotypes that exhibit variation in their ability to tolerate soil ammonium is a research priority. Here, we evaluate how soil ammonium impacts canola root and shoot growth and characterise differences among canola genotypes in regard to resistance to ammonium toxicity. In the first experiment, eight ammonium chloride treatments and five calcium nitrate treatments were tested for their impact on the canola genotype Crusher TT, where high application (60 mg N/kg soil) significantly decreased the dry weight of canola shoots and roots and acidified the soil from pHCaCl2 5.9 to 5.6. In the second experiment, 30 canola genotypes were screened at selected concentrations of NH4+-N, using nitrate as the control. There was wide variation among genotypes in sensitivity to high NH4+-N application. Genotypes G16, G26, and G29 had greater shoot dry weights and the highest shoot N concentration of all genotypes, and G16, G26, and G28 had root dry weight up to 35% higher at high soil NH4+-N compared with other genotypes. In contrast, genotypes G3, G13, and G30 showed the largest reduction in shoot weight, and genotypes G13, G23, and G30 showed the largest reduction in root weight at high NH4+-N application. Residual NH4+-N/kg soil in soil was higher for sensitive than resistant genotypes, suggesting lower NH4+-N use in the former. These results reveal the potential for selecting canola genotypes that are resistant to high NH4+-N concentrations in soil.

Assessing Drought Tolerance of Newly Developed Tissue-Cultured Canola Genotypes under Varying Irrigation Regimes

Drought is a major abiotic stress that greatly affects canola growth, production, and quality. Moreover, water scarcity is projected to be more severe and frequent as a result of climate change, in particular in arid environments. Thereupon, developing drought-tolerant and high-yielding canola genotypes has become more critical to sustaining its production and ensuring global food security with the continuing population growth. In the present study, ten canola genotypes comprising six developed tissue-cultured canola genotypes, two exotic genotypes, and two commercial cultivars were evaluated under four irrigation regimes. The applied irrigation regimes were well-watered (100% crop evapotranspiration, ETc), mild drought (80% ETc), moderate drought (60% ETc), and severe drought (40% ETc) conditions. Drought-stress treatments (80, 60, and 40% ETc) gradually reduced the chlorophyll content, relative water content, flowering time, days to maturity, plant height, number of pods, number of branches, seed yield, and oil percentage, and increased proline, phenolic, anthocyanin, and glycine betaine contents. The evaluated genotypes exhibited varied responses to drought-stress conditions. The developed tissue-cultured genotypes T2, T3, and T1, as well as exotic genotype Torpe, possessed the highest performance in all evaluated parameters and surpassed the other tested genotypes under water-deficit conditions. Overall, our findings elicited the superiority of certain newly developed tissue-cultured genotypes and exotic ones compared with commercial cultivars, which could be exploited in canola breeding under water-deficit conditions.

Role of Pollinators on Seed Yield and Oil for Some Canola (Brassica napus L.) Genotypes

Role of Pollinators on Seed Yield and Oil for Some Canola (Brassica napus L.) Genotypes

Influence of the selection of cold-resistant winter canola genotypes at the early stages of ontogenesis on the quantitative and qualitative characters of plants

Influence of the selection of cold-resistant winter canola genotypes at the early stages of ontogenesis on the quantitative and qualitative characters of plants

Response of Canola productivity to integration between mineral nitrogen with yeast extract under poor fertility sandy soil condition

Canola is one of the important oil crops and is considered the most promising oil source and adapts to reclaimed soil conditions. The current study aimed to evaluate the influence of yeast extract (YE) integrated with nitrogen (N) rates and treatments were arranged as follows: Control (without F0), 95 kg N ha−1 (F1), 120 kg N ha−1 (F2), 142 kg N ha−1 (F3), 95 kg N ha−1 + YE (F4), 120 kg N ha−1 + YE (F5) and 142 kg N ha−1 + YE (F6) on physico-chemical properties, yield and its components for three Canola genotypes i.e. AD201 (G1), Topaz and SemuDNK 234/84 under the sandy soil. In this work, Results reveal that increasing rates of Nitrogen fertilization from 95 kg N ha−1 to 142 kg N ha−1 have a great effect on physicochemical properties yield and its components. The result proved that 142 kg N ha−1 with yeast treatment was the best treatment for three Canola genotypes. Also, the result showed that seed yield was positively correlated with Chl. a/b ratio, plant height, number of branches/plant, number of pods/plant, and number of seeds/pod, and a strong negative correlation was detected between seed oil percentage when the amount of nitrogen fertilization applied without or with yeast extract is increased.

Productivity Improvement of Canola Genotypes Under Salinity Stress Conditions by Integration between Mineral and Nano-Scale forms of Nitrogen Fertilizer

Productivity Improvement of Canola Genotypes Under Salinity Stress Conditions by Integration between Mineral and Nano-Scale forms of Nitrogen Fertilizer

Canola Seed Priming and Its Effect on Gas Exchange, Chlorophyll Photobleaching, and Enzymatic Activities in Response to Salt Stress

Canola is the second-largest oil seed crop in the world, providing oil mainly composed of long-chain fatty acids (C14 to C20). When mixed with fossil-diesel, canola-based biofuel can be used in passenger vehicles, trucks, or even in aviation. Canola is the most productive type of biofuel due to its oil’s long-chain and unbranched fatty acid composition, which makes it more fluid. However, canola yields are constrained by drought and salinity that can aggravate climate change, resulting in negative consequences. Therefore, it is becoming necessary for studies that involved the canola salt-tolerant genotypes to consider soil salinization by use of saline soil or salinized soil by a non-efficient irrigation method. This study was carried out to assess the effects of salinity on seed germination and the effect of CaCl2 (ψs = −1.2 MPa) on the promotion of regenerated plant memory when a new cycle of stress occurs. Our experiment shows that salt-stressed canola plants resulted in a high reduction in chlorophylls and carotenoids, with a high impact on gas exchange and a reduction in the efficiency of the chloroplast electron chain transporter, producing the negative effect of reduced molecules that affect the membrane integrity. However, canola seed priming could produce a memory in the regenerated plants when the second round of salt stress was applied. This research concludes that canola genotypes appear to have a tolerance mechanism against salt stress which could be an important trait for developing high-yielding canola varieties in future breeding programs under salt stress conditions.

Efficacy of Biochar-Supplemented Soil for Modification of Physio-Biochemical Attributes of Canola (Brassica napus L.) Genotypes under Different Moisture Regimes

Efficacy of Biochar-Supplemented Soil for Modification of Physio-Biochemical Attributes of Canola (Brassica napus L.) Genotypes under Different Moisture Regimes

IMPACT OF SALICYLIC ACID TREATMENTS ON YIELD ATTRIBUTES OF CANOLA AND GROWTH OF Schizaphis Graminum

The present investigation was studied the effect of various trends of salicylic acid on canola yield traits besides, aphid interaction. For this purpose, the research trial was conducted under the semi-natural conditions of the net house of the Plant Pathology Research Institute, Ayub Agriculture Research Institute Faisalabad during November 6, 2019. The canola seeds were planted in the pots following (RCBD) with six treatments (0 ppm, 10 ppm, 20 ppm, 40 ppm, 80 ppm and 160 ppm) and three replications. The maximum plant height (212.41cm), number of pods per plant (675.67), number of seeds per pod (25.29), thousand seed weight (3.85g), biological yield (24817.2 kg-1), seed yield (3666.33 kg-1), seed oil content (47.16%) and protein contents (24.1%) were observed with the application of the high concentration of salicylic acid (160 ppm/pot) over control. A significant increase in harvest index increased (18.8) was recorded with the application of 20 ppm concentration of salicylic acid. The exogenous application of salicylic acid treatments significantly increased the mortality percentage of 1st, 2nd and 3rd instar nymph. The maximum mortality percentage of 1st, 2nd and 3rd instar nymph were recorded 43.67, 76.6 and 83% with the application of high level of salicylic acid concentration (160 ppm/pot) as compared to the control, respectively. The honey drops of aphid and nymph survival percentage were reduced with the foliar application of salicylic acid over control. The minimum honey drops (17.9%), nymph survival (61.8%) and reproductive periods (18%) were recorded with the use of salicylic acid. It was concluded that foliar application of salicylic acid had a significant impact on yield attributes of canola genotypes and biology of canola aphid.

Main factors affecting nutrient and water use efficiencies in spring canola in North America: a review of literature and analysis

Improving nutrient and water use efficiencies by optimizing field management practices are important strategies to increase economic and environmental sustainability of canola production in North America. The objective of this study was to review recent research publications and quantitatively assess the impact of field management practices on the efficiency of water and selected macronutrients [nitrogen (N) and sulfur (S)] in canola and to identify the most effective cultural practices for improved efficiencies. The results showed that, overall, the addition of N and S inputs in studies across North America increased yield but had a negative impact on nitrogen use efficiency (NUE) and sulfur use efficiency (SUE) compared with corresponding controls. Split-applied N in spring can improve NUE, but these improvements are mostly dependent on the soil moisture content. SUE is improved when N is supplied to complement the S application. Sulfate forms of S are more readily available and should be applied early in the season, whereas elemental S must be applied in the fall to improve SUE. Maintenance of adequate soil moisture conditions during the reproductive phase of the canola crop improves water use efficiency (WUE). Supplementary irrigation improves SUE, but most canola crops are grown under rain-fed conditions in North America. Maintaining tall stubble until spring and then incorporating it with N improved WUE in canola. In summary, our analyses suggest that further research is required on the integration of canola genotypes with improved nutrient and water use efficiencies and effective management.

Effects of Foliar Application of Gibberellic -Acid3 on the Growth and Yield of Canola (Brassica napus L.) Genotypes

Plant growth regulators play a central part in plant life. Plant hormones help to manage the equilibrium of phytohormones. Gibberellic acid, which is well known as a plant growth promoting hormone, is involved in a variety of activities related to plant growth and development. An experiment was performed at the Nuclear Institute of Agriculture, Tandojam with four promising canola genotypes in order to determine the impact of GA3 foliar application on canola growth and output during the rabi season in 2017-2018. The results showed that growth regulators levels significantly influenced the growth and yield of canola crops. It was observed that earlier days to maturity (108.39) was recorded in genotype R00-100/6, while maximum plant height (162.75), branches per plant (10.33), siliquae per plant (362.24), siliqua length (7.39 cm), seeds per siliqua (21.49), seed index (4.50 g) and seed yield (1443.08 kg ha-1) were observed with the application of GA3 5g ha-1 in SURHRAN-2012, followed by the application of GA3 6 g ha-1 genotype R00-125/12 and Rainbow (P). The results suggested that the variety SURHRAN-2012 x GA35 g ha-1 (foliar application) is comprised a suitable combination for obtaining maximum yield. Such application of GA3 is very advantageous in the field of plant development.

Genotypic variation of conservative and profligate water use in the vegetative and reproductive stages of canola (

Limited water availability is a major constraint to canola (Brassica napus L.) yield in the Mediterranean-type climate region. Selecting and breeding for genotypes with conservative water use characteristics is a promising strategy to improve yield in this environment. Three experiments were conducted to investigate transpiration responses (TR) to vapour pressure deficit (VPD) and progressive soil drying with 8-20 canola genotypes. We used the linear-plateau model to describe TR to elevated VPD and decreased fraction of transpirable soil water (FTSW) and identified the VPD and FTSW thresholds for plant to limit its transpiration. Canola genotypes showed significant variations in both VPD and FTSW thresholds. The genotypes with conservative water use reduced TR at a lower VPD threshold and decreased TR at a higher FTSW threshold than the profligate ones. We found that the conservative genotypes had low VPD and high FTSW thresholds while the profligate ones had high VPD and low FTSW thresholds. This conservative and profligate water use characteristics were consistent during both vegetative and reproductive stages. Furthermore, the relative yield of genotypes under drought conditions was positively related to the FTSW thresholds during the reproductive stage, indicating the better relative yield performance of conservative genotypes in water-limited farming system. We conclude that canola genotypes with lower VPD and higher FTSW thresholds could conserve water and defer water use for reproductive growth while the profligate genotypes can be deployed to take advantage of high rainfall in the high rainfall zone of southern Australia.