Pathogenic variation in Australian isolates of Mycosphaerella graminicola

Seven isolates of Mycosphaerella graminicola gave a range of infection patterns when inoculated onto 20 wheat testers in glasshouse tests. Linear modelling and the biplot technique indicated host-pathogen interaction, hence evidence for physiologic specialization. Two isolates from Western Australia (WA) gave only limited disease on the cultivar Egret which is field resistant in WA. The cvv. Heron and Robin which are related to each other and to Egret also showed limited disease with the WA isolates and with certain NSW cultures. Five New South Wales (NSW) isolates produced moderate to severe infection on this cultivar which is field susceptible in NSW. Among the bread wheats used as sources of resistance in southern NSW only one, M1696, remained healthy with all isolates; nine other lines developed little disease with most isolates but more infection with other isolates, especially two isolates isolated from the field in severe epidemics. There was agreement between replicates within and between experiments. The relevance of these findings to breeding programs is discussed.

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Identification of Resistance to Powdery Mildew in Chile Pepper

HortScience ◽

10.21273/hortsci13596-18 ◽

2019 ◽

Vol 54 (1) ◽

pp. 4-7 ◽

Cited By ~ 3

Author(s):

Jack E. McCoy ◽

Paul W. Bosland

Keyword(s):

Powdery Mildew ◽

Severe Infection ◽

Capsicum Frutescens ◽

Capsicum Chinense ◽

Sources Of Resistance ◽

Breeding Programs ◽

Chile Pepper ◽

Commercially Important ◽

Chile Peppers ◽

Capsicum Chacoense

Powdery mildew [Leveillula taurica (Lév.) Arn] is a fungus causing epidemics on chile peppers (Capsicum sp.) worldwide. It was first observed in New Mexico in the late 1990s and has been a reoccurring issue. During the 2017 growing season, environmental conditions were highly favorable for powdery mildew development and severe infection was observed. This provided a unique opportunity to identify novel sources of resistance in Capsicum to powdery mildew. In the present study, the incidence and severity of powdery mildew was evaluated for 152 chile pepper accessions comprising different cultivars and species. Major differences in disease severity and incidence were observed among the accessions. Of the 152 accessions, 53 were resistant, i.e., received a disease index (DI) score of ≤1. When examining across Capsicum species, 16 Capsicum annuum accessions, all 8 Capsicum baccatum, all 21 Capsicum chinense, 5 of 6 Capsicum frutescens, the Capsicum chacoense accession, and the Capsicum rhomboideum accession were resistant. These results provide several accessions with resistance that can be used in breeding programs. Especially important are the C. annuum resistant accessions, as this resistance can be more quickly incorporated into commercially important C. annuum cultivars as compared with interspecific hybridizations.

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Characterization of the high α -amylase levels in grain of the wheat cultivar BD 159

Australian Journal of Agricultural Research ◽

10.1071/ar9941002 ◽

1994 ◽

Vol 45 (5) ◽

pp. 1003 ◽

Cited By ~ 12

Author(s):

DJ Mares ◽

K Mrva ◽

JF Panozzo

Keyword(s):

Amylase Activity ◽

Wheat Cultivar ◽

New South ◽

Wheat Breeding ◽

Cool Temperature ◽

Wheat Varieties ◽

Breeding Programs ◽

South Wales ◽

Late Maturity

TThe advanced wheat breeding line BD 159, from Victoria, exhibited a wide variation in falling number values at trial sites in 1990 when corresponding values for standard cultivars were uniformly high. The variable and unpredictable behaviour of BD 159 appears to be typical of a number of advanced lines and parental stocks from Australian breeding programs. The grain samples of BD 159 with low falling numbers had elevated levels of a-amylase which was distributed evenly in the proximal and distal halves of the grains. This distribution pattern, which was quite distinct from the steep gradient in a-amylase activity typical of germinated grains, and the absence of any evidence of sprouting indicated that the anomalous behaviour of BD 159 is a new and different form of the late maturity a-amylase syndrome previously described in wheat varieties such as Spica and Lerma 52. The high levels of a-amylase were reproduced at Narrabri in northern New South Wales when plants were transplanted from the field and allowed to ripen in a cool temperature glasshouse. Plants which were left to ripen in the field produced grain with a very low a-amylase activity.

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A regional adaptation analysis of oats in New South Wales and southern Queensland for grain yield and dry matter production

Australian Journal of Agricultural Research ◽

10.1071/ar00016 ◽

2000 ◽

Vol 51 (8) ◽

pp. 961 ◽

Cited By ~ 2

Author(s):

M. R. Herring ◽

L. O'Brien

Keyword(s):

New South ◽

New South Wales ◽

Genetic Material ◽

Northern Region ◽

Forage Production ◽

Breeding Programs ◽

Breeding Lines ◽

South Wales ◽

Regional Adaptation ◽

Oat Breeding

A regional adaptation analysis was conducted to identify oat genotypes with potential for release as varieties or use as parents in breeding programs for New South Wales (NSW) and southern Queensland. This analysis used 5 trial sites (Toowoomba, Moree, Narrabri, Armidale, Temora) and was conducted over 3 years using 71 oat (Avena sp.) genotypes. Genotypes were selected to represent various phenology types from early to late maturing as well as being representative of a variety of end uses including grain, grazing, dual purpose, and naked oats. Australian breeding lines and varieties composed most of the genotypes in the analysis; however, overseas material was also included. Multivariate analysis indicated that the area studied could be divided into 2 subregions. The northern sites of Toowoomba, Moree, and Narrabri were in one cluster, whereas Temora and Armidale formed another. Genotypes formed groups which were largely related to their phenology. Results indicated that there was a group of genotypes which produced above average grain yields over the entire region. Oats in this group were primarily of mid-season phenology and were all from the existing Australian oat breeding programs. Oats of mid- and late-season phenology were better suited to the Armidale and Temora region where conditions are cooler and the growing season longer. Early maturing oats were identified as types suitable for high yielding grain oats for the northern region. However, it is recognised that improvement in rust resistance of these genotypes would be necessary for reliable and profitable grain production in this area. Breeding oats for northern NSW and southern Queensland would be possible using genotypes from the existing Australian oat breeding programs. The quick maturing oats from Agriculture Western Australia seemed especially well suited to this purpose. From the genotypes used in this study there seemed to be a shortage of late maturing oat types. If oats for hay or forage production were required, evaluation of late maturing genetic material from overseas may be required.

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A single recessive gene confers effective resistance to powdery mildew of field pea grown in northern New South Wales

Australian Journal of Experimental Agriculture ◽

10.1071/ea01142 ◽

2003 ◽

Vol 43 (4) ◽

pp. 373 ◽

Cited By ~ 8

Author(s):

S. M. Liu ◽

L. O'Brien ◽

S. G. Moore

Keyword(s):

Powdery Mildew ◽

New South ◽

New South Wales ◽

Recessive Gene ◽

Single Recessive Gene ◽

Breeding Programs ◽

South Wales ◽

Plant Breeding Institute ◽

Recessive Genes ◽

Resistant Genotypes

Reactions to powdery mildew (Erysiphe pisi Syd.) of a range of varieties, advanced lines and pea germplasm from the Australian Temperate Field Crops Collection (ATFCC) were evaluated under field conditions at Narrabri, New South Wales. Thirteen resistant genotypes, including 3 M257 sister lines [M257-2-1 (Mukta), M257-3-6 and M257-5-1], Glenroy, Kiley and PSI 11 from Australian breeding programs, and LE 25 (ATC 1275), ATC 649, ATC 767, ATC 823, ATC 1036, ATC 1121 and ATC 1181 from the ATFCC, along with 8 susceptible lines Dinkum, Bohatyr, Jupiter, Greenfeast, Solara, P441-6, Trapper and Cressy Blue, were used to make resistant × resistant, resistant × susceptible and susceptible × susceptible combinations to examine the inheritance of resistance. Parental lines and F1 and F2 populations were evaluated in the field under natural disease epiphytotics at the Plant Breeding Institute, Narrabri, during the winters of 1996 and 1997. In 1996, resistant and susceptible F2 plants were selected from 5 crosses, and further examined as F3 families in 1997. No fully resistant line was identified among the parents. F1 reactions indicated that resistance was governed by recessive genes and there were no maternal effects. Segregation patterns in the F2 and F3 generations supported the hypothesis of resistance in the genotypes M257-5-1, Glenroy, Kiley, ATC 649 and ATC 1121 being conferred by the same single recessive gene.

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Comparison of controls on development in breeding lines from Australian and CIMMYT/ICARDA winter and facultative wheat breeding programs

Australian Journal of Agricultural Research ◽

10.1071/ar9960001 ◽

1996 ◽

Vol 47 (1) ◽

pp. 1 ◽

Cited By ~ 5

Author(s):

LDJ Penrose ◽

M Mosaad ◽

TS Payne ◽

G Ortiz-Ferrara ◽

HJ Braun

Keyword(s):

New South ◽

Late Summer ◽

Wheat Breeding ◽

Breeding Programs ◽

Breeding Lines ◽

South Central ◽

South Wales ◽

Improvement Programs ◽

Integrated Response ◽

Good Proportion

This study sought to compare developmental controls in breeding a within two winter wheat improvement programs, one Australian and a CIMMYT/ICARDA program based in West Asia. Developmental controls considered were intrinsic earliness, and responses to photoperiod and to vernalization. The reliability with which each control on development had been measured was tested in separate experiments using the wheats utilized in the Australian program. Measures of intrinsic earliness showed significant agreement between experiments, better agreement being found for response to photoperiod and between integrated response to vernalization and time to double ridge after late summer sowings. The wheats utilized in the CIMMYTI/CARDA programs were found to be quick in intrinsic earliness, and to possess little response to photoperiod. While these controls varied more for the wheats utilized in the Australian program, commercial Australian winter wheats were similar to the CIMMYTI/CARDA lines. Lines utilized by both programs were represented by types with spring, facultative and winter habit. The clearest differences between programs were that CIMMYTI/CARDA winter wheats appeared to have much stronger response to vernalization than the Australian winter wheats. These findings suggest breeders would find a good proportion of segregates, from crosses between the Australian and the CIMMYTI/CARDA winter wheats, to be developmentally adapted to south-central New South Wales. This suggests CIMMYTI/CARDA winter wheats provide a matching pool from which to access germplasm to introduce new characters into Australian winter wheats.

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