AAC Delhi field pea

AAC Delhi is a semi-leafless, large-seeded yellow field pea (Pisum sativum L.) variety developed at Agriculture and Agri-Food Canada Lacombe Research and Development Centre, Lacombe, Alberta, Canada. It has high yielding potential, medium maturity and good lodging resistance. AAC Delhi has the maturity of 95 days, and one-thousand-seed weight of 288 g. AAC Delhi is resistant to powdery mildew (caused by Erysiphe pisi Syd.), and is moderately susceptible to mycosphaerella blight (caused by Mycosphaerella pinodes) and fusarium wilt (caused by Fusarium oxysporum). AAC Delhi is adapted to all field growing regions in western Canada.

AAC Profit field pea

AAC Profit is a semi-leafless, yellow cotyledonary field pea (Pisum sativum L.) cultivar developed at Agriculture and Agri-Food Canada Lacombe Research and Development Centre, Lacombe, Alberta, Canada. It has a maturity of 101 d, thousand-seed weight of 218 g, and a lodging score of 4.1 on the scale of 1-9 (1=upright, 9=prostrate). The seed crude protein content of AAC Profit is 24.5%. AAC Profit is resistant to powdery mildew (caused by Erysiphe pisi), and moderately susceptible to mycosphaerella blight (caused by Mycosphaerella pinodes) and fusarium wilt (caused by Fusarium oxysporum).

AAC Lorlie maple pea

AAC Lorlie is a maple pea variety developed at Lacombe Research and Development Centre of Agriculture and Agri-Food Canada. It has large seeds with one-thousand-seed weight of 236-269 g. The seed coat colour of AAC Lorlie has mottled brown patterns on a light sage background, and cotyledon colour of AAC Lorlie is yellow. The variety reaches maturity 100-101 days after seeding. It has a pre-harvesting lodging score of 5.4-6.6 on a 0-9 scale. The variety is resistant to powdery mildew caused by Erysiphe pisi Syd..

Partial Resistance Against Erysiphe pisi and E. trifolii Under Different Genetic Control in Lathyrus cicera: Outcomes from a Linkage Mapping Approach

Powdery mildew infections are among the most severe foliar biotrophic fungal diseases in grain legumes. Several accessions of Lathyrus cicera (chickling pea) show levels of partial resistance to Erysiphe pisi, the causal agent of pea powdery mildew, and to E. trifolii, a powdery mildew pathogen recently confirmed to infect pea and Lathyrus spp. Nevertheless, the underlying L. cicera resistance mechanisms against powdery mildews are poorly understood. To unveil the genetic control of resistance against powdery mildews in L. cicera, a recombinant inbred line population segregating for response to both species was used in resistance linkage analysis. An improved L. cicera genetic linkage map was used in this analysis. The new higher-density linkage map contains 1,468 polymorphic loci mapped on seven major and two minor linkage groups, covering a total of 712.4 cM. The percentage of the leaf area affected by either E. pisi or E. trifolii was recorded in independent screenings of the recombinant inbred line population, identifying a continuous range of resistance-susceptibility responses. Distinct quantitative trait loci (QTLs) for partial resistance against each pathogen were identified, suggesting different genetic bases are involved in the response to E. pisi and E. trifolii in L. cicera. Moreover, through comparative mapping of L. cicera QTL regions with the pea reference genome, candidate genes and pathways involved in resistance against powdery mildews were identified. This study extended the previously available genetic and genomic tools in Lathyrus species, providing clues about diverse powdery mildew resistance mechanisms useful for future resistance breeding of L. cicera and related species.

AAC Asher field pea

AAC Asher is a semi-leafless, medium to large seeded yellow cotyledon field pea (Pisum sativum L.) variety developed at Agriculture and Agri-Food Canada, Lacombe Research and Development Centre, Lacombe, Alberta, Canada. It has high yielding potential, early to medium maturity and good lodging resistance. AAC Asher has maturity of 94 days, and one-thousand-seed weight of 257 g. AAC Asher is resistant to powdery mildew (caused by Erysiphe pisi Syd.), moderately tolerant to mycosphaerella blight (caused by Mycosphaerella pinodes) and fusarium wilt (caused by Fusarium oxysporum). AAC Asher is adapted to all field growing regions in western Canada.

DNA Fingerprinting and Species Identification Uncovers the Genetic Diversity of Katsouni Pea in the Greek Islands Amorgos and Schinoussa

Pea (P. sativum L.), one of the most important legume crops worldwide, has been traditionally cultivated in Lesser Cyclades since ancient times. The commonly known traditional pea cultivar, ‘Katsouni’, is endemic to the islands of Amorgos and Schinoussa and is of great local economic importance. Despite the widespread cultivation of ‘Katsouni’ in both islands, it is still unknown whether the current Schinoussa and Amorgos pea populations are distinct landraces, and if they have common evolutionary origin. To assist conservation and breeding of the pea crop, the genetic diversity and phylogenetic relationships of 39 pea samples from Amorgos and 86 from Schinoussa were studied using DNA barcoding and ISSR marker analyses. The results indicate that both populations are different landraces with distinct geographical distribution and are more closely related to P. sativum subsp. elatius than the P. abyssinicum and P. fulvum species. Further characterization of the ‘Katsouni’ landraces for functional polymorphisms regarding pathogen resistance, revealed susceptibility to the powdery mildew (Erysiphe pisi DC.). This work represents the first investigation on the genetic diversity and population structure of the ‘Katsouni’ cultivar. Exploiting the local genetic diversity of traditional landraces is fundamental for conservation practices and crop improvement through breeding strategies.

Two Novel er1 Alleles Conferring Powdery Mildew (Erysiphe pisi) Resistance Identified in a Worldwide Collection of Pea (Pisum sativum L.) Germplasms

Powdery mildew caused by Erysiphe pisi DC. severely affects pea crops worldwide. The use of resistant cultivars containing the er1 gene is the most effective way to control this disease. The objectives of this study were to reveal er1 alleles contained in 55 E. pisi-resistant pea germplasms and to develop the functional markers of novel alleles. Sequences of 10 homologous PsMLO1 cDNA clones from each germplasm accession were used to determine their er1 alleles. The frame shift mutations and various alternative splicing patterns were observed during transcription of the er1 gene. Two novel er1 alleles, er1-8 and er1-9, were discovered in the germplasm accessions G0004839 and G0004400, respectively, and four known er1 alleles were identified in 53 other accessions. One mutation in G0004839 was characterized by a 3-bp (GTG) deletion of the wild-type PsMLO1 cDNA, resulting in a missing valine at position 447 of the PsMLO1 protein sequence. Another mutation in G0004400 was caused by a 1-bp (T) deletion of the wild-type PsMLO1 cDNA sequence, resulting in a serine to leucine change of the PsMLO1 protein sequence. The er1-8 and er1-9 alleles were verified using resistance inheritance analysis and genetic mapping with respectively derived F2 and F2:3 populations. Finally, co-dominant functional markers specific to er1-8 and er1-9 were developed and validated in populations and pea germplasms. These results improve our understanding of E. pisi resistance in pea germplasms worldwide and provide powerful tools for marker-assisted selection in pea breeding.