or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. C anola (Brassica napus L.) is an oil seed crop that con-ABSTRACT Water being a major limiting factor in crop production, prediction of the growth and yield response of crop to water is important. Field experiments were conducted in 2009 and 2010 at Wagga Wagga (Australia) to calibrate and validate a water productivity model AquaCrop for canola (Brassica napus L.). Th e calibrated model was able to accurately simulate evolution of canopy cover, biomass accumulation, and grain yield, with low values of root mean-square error and model effi ciency, and Willmot's d statistics values close to unity. However, the model overestimated biomass and yield of canola grown in 2009 under a high moisture stress condition. Measured and simulated biomass of Skipton variety grown in 2010 to validate AquaCrop were 21. 1 and 19.1 t ha -1 , respectively. Th e grain yield was 3.18 and 3.11 t ha -1 , respectively. In the drought year of 2009, measured and simulated biomass were 8.13 and 9.56 t ha -1 , respectively, for the Bln3343-Co0401 variety used for validation. Th e grain yield was 1.75 and 1.96 t ha -1 , respectively. Although AquaCrop was able to capture the trend, it tended to slightly overestimate soil water content during the season. To standardize the conservative parameters developed in this study, further tests are recommended under different environmental and management conditions.

PCR-based genic and microarray-based Diversity Arrays Technology (DArT™) markers were used to determine genetic diversity in 94 accessions of white lupin (Lupinus albus L.) comprising Australian and foreign cultivars, landraces, and advanced breeding lines from Australian breeding programs. A total of 345 (50 PCR-based and 295 DArT-based) polymorphic fragments were identified, which were used to determine the genetic diversity among accessions. Both cluster analysis of bivariate marker data using UPGMA, and principal coordinate analysis, indicated a high level of genetic diversity in the germplasm. Our results showed that both types of markers used in this study are suitable for estimation of genetic diversity. Landrace accessions from Ethiopia formed a very distinct and separate grouping with both marker systems. Australian cultivars and breeding lines were clustered together and tended to be distinct from European landraces. These findings will allow breeders to select appropriate, diverse parents to broaden the genetic base of white lupin breeding populations.

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Sustainable canola production is essential to meet growing human demands for vegetable oil, biodiesel, and meal for stock feed markets. Blackleg, caused by the fungal pathogen, Leptosphaeria maculans is a devastating disease that can lead to significant yield loss in many canola production regions worldwide. Breakdown of race-specific resistance to L. maculans in commercial cultivars poses a constant threat to the canola industry. to identify new alleles, especially for quantitative resistance (QR), we analyzed 177 doubled haploid (DH) lines derived from an RP04/Ag-Outback cross. DH lines were evaluated for QR under field conditions in three experiments conducted at Wagga Wagga (2013, 2014) and Lake Green (2015), and under shade house conditions using the 'ascospore shower' test. DH lines were also characterized for qualitative R gene-mediated resistance via cotyledon tests with two differential single spore isolates, IBCN17 and IBCN76, under glasshouse conditions. Based on 18,851 DArTseq markers, a linkage map representing 2,019 unique marker bins was constructed and then utilized for QTL detection. Marker regression analysis identified 22 significant marker associations for resistance, allowing identification of two race-specific resistance R genes, Rlm3 and Rlm4, and 21 marker associations for QR loci. At least three SNP associations for QR were repeatedly detected on chromosomes A03, A07 and C04 across phenotyping environments. Physical mapping of markers linked with these consistent QR loci on the B. napus genome assembly revealed their localization in close proximity of the candidate genes of B. napus BnaA03g26760D (A03), BnaA07g20240D (A07) and BnaC04g02040D (C04). Annotation of these candidate genes revealed their association with protein kinase and jumonji proteins implicated in defense resistance. Both Rlm3 and Rlm4 genes identified in this DH population did not show any association with resistance loci detected under either field and/ or shade house conditions (ascospore shower) suggesting that both genes are ineffective in conferring resistance to L. maculans in Australian field conditions. Taken together, our study identified sequencebased molecular markers for dissecting R and QR loci to L. maculans in a canola DH population from the RP04/Ag-Outback cross. Blackleg, caused by the fungal pathogen Leptosphaeria maculans, is a major disease of the canola (Brassica napus L., A n A n C n C n , 2n = 4× = 38) industry especially in Australia, Canada, and France. Developing new cultivars resistant to blackleg is recognized as the most economically and environmentally safe strategy to control yield losses. Traditional breeding for blackleg resistance largely relies on the selection of elite 'good looking' lines in disease nurseries where there is high disease pressure from a diverse pathogen population. Utilizing this strategy, several canola varieties have been developed and released for commercial cultivation with ratings of moderate-to highly-resistant (to blackleg) without any prior knowledge of either r...

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Phomopsis blight in Lupinus albus is caused by a fungal pathogen, Diaporthe toxica. It can invade all plant parts, leading to plant material becoming toxic to grazing animals, and potentially resulting in lupinosis. Identifying sources of resistance and breeding for resistance remains the best strategy for controlling Phomopsis and reducing lupinosis risks. However, loci associated with resistance to Phomopsis blight have not yet been identified. In this study, quantitative trait locus (QTL) analysis identified genomic regions associated with resistance to Phomopsis pod blight (PPB) using a linkage map of L. albus constructed previously from an F8 recombinant inbred line population derived from a cross between Kiev-Mutant (susceptible to PPB) and P27174 (resistant to PPB). Phenotyping was undertaken using a detached pod assay. In total, we identified eight QTLs for resistance to PPB on linkage group (LG) 3, LG6, LG10, LG12, LG17 and LG27 from different phenotyping environments. However, at least one QTL, QTL-5 on LG10 was consistently detected in both phenotyping environments and accounted for up to 28.2% of the total phenotypic variance. The results of this study showed that the QTL-2 on LG3 interacts epistatically with QTL-5 and QTL-6, which map on LG10 and LG12, respectively.

Blackleg disease is caused by the stubble-borne pathogen Leptosphaeria maculans and results in significant yield losses in canola (Brassica napus) worldwide. Control of this disease includes breeding for resistance, fungicides and cultural practices including stubble management. In recent years, cropping systems have changed with the introduction of no-till farming and inter-row sowing, and it is unknown what impact these changes have had on stubble retention. The aim of this study is to investigate the impact of inter-row sowing on stubble retention and spore release. The use of inter-row sowing resulted in 25–48% of stubble remaining standing (vertical) in fields after 1 year. Furthermore, spore release was significantly (P < 0.05) delayed in stubble that remained vertical in the field compared with stubble lying down, with total spore release from vertical stubble 66% less than from horizontal stubble. The impact these changes have on the epidemiology of blackleg disease remains unknown.