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

1994 ◽  
Vol 45 (5) ◽  
pp. 1003 ◽  
Author(s):  
DJ Mares ◽  
K Mrva ◽  
JF Panozzo

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.

1996 ◽  
Vol 47 (1) ◽  
pp. 1 ◽  
Author(s):  
LDJ Penrose ◽  
M Mosaad ◽  
TS Payne ◽  
G Ortiz-Ferrara ◽  
HJ Braun

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.


1992 ◽  
Vol 32 (4) ◽  
pp. 447 ◽  
Author(s):  
G Sweeney ◽  
RS Jessop ◽  
H Harris

The yields and yield structure of cultivars of triticales and bread wheats (with a range of phasic development patterns in both species) were compared in 2 field experiments at Narrabri in northern New South Wales. The experiments were performed on a grey cracking clay soil with irrigation to prevent severe moisture stress. Triticales, both early and midseason types, appeared to have reached yield parity with well-adapted wheat varieties. Meaned over the 2 experiments and all sowings, the triticales yields were 19% greater than the bread wheats. Triticales were generally superior to wheat in all components of yield of the spike (1000-grain weight, grain number/spikelet and spikelet number/spike), whilst the wheats produced more spikes per unit area. The triticales also had higher harvest indices than the wheats. The results are discussed in relation to the overall adaptability of triticale for Australian conditions.


1995 ◽  
Vol 46 (5) ◽  
pp. 921 ◽  
Author(s):  
B Ballantyne ◽  
F Thomson

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.


2010 ◽  
Vol 61 (2) ◽  
pp. 153 ◽  
Author(s):  
M. K. Tan ◽  
A. P. Verbyla ◽  
B. R. Cullis ◽  
P. Martin ◽  
A. W. Milgate ◽  
...  

Late maturity α-amylase (LMA) in wheat is a defect where high-isoelectric point (pI) α-amylase accumulates in the ripening grain. Wheat genotypes vary in expression from zero to high levels of α-amylase, the latter with detrimental consequences on their use for value-added end products. Expression in each genotype is characterised by varying numbers of grains affected and different levels in each grain. Analysis of a doubled haploid (DH) population (188 lines) from WW1842 × Whistler has identified significant QTL on chromosomes 2DL, 3A, 3B, 3D, 4B, 4D, 5DS and 5BL. The 4B LMA allele (P < 0.0001) from Whistler is closely linked to the QTL for the ‘tall’ allele (P < 0.0001) of the Rht-B1 gene. The 4D LMA QTL (P < 0.0001) in WW1842 co-locates with the QTL for the ‘tall’ allele (P < 0.0001) of the Rht-D1 gene. This study has shown for the first time that a DH cross between two semi-dwarf cultivars with low or no LMA produces ~25% of progeny lines of the ‘tall’ genotypes with a high frequency of LMA. This is attributed to the large additive positive effects from the combination of one recessive ‘tall’ Rht-B1 gene and one recessive ‘tall’ Rht-D1 gene. High-yielding semi-dwarf genotypes with different combinations of Rht-B1 and Rht-D1 alleles which have very low or non-existent LMA expression (e.g. WW1842 and Whistler) may meet industry criteria for registration as commercial wheat varieties. However, when they are used as breeding lines, the cross produces some progeny genotypes with severe levels of LMA. These LMA genotypes comprise the gibberellic acid-sensitive ‘tall’ progenies and a very small proportion of semi-dwarfs. Thus, it is of paramount importance to screen the defect in wheat breeding programs. The suite of QTL identified for LMA will enable the use of marker assisted selection in the pyramiding of the beneficial QTL to maximise yield and minimise (or eliminate) LMA in semi-dwarf genotypes.


1995 ◽  
Vol 35 (1) ◽  
pp. 93 ◽  
Author(s):  
RD FitzGerald ◽  
ML Curll ◽  
EW Heap

Thirty varieties of wheat originating from Australia, UK, USA, Ukraine, and France were evaluated over 3 years as dual-purpose wheats for the high rainfall environment of the Northern Tablelands of New South Wales (mean annual rainfall 851 mm). Mean grain yields (1.9-4.3 t/ha) compared favourably with record yields in the traditional Australian wheatbelt, but were much poorer than average yields of 6.5 t/ha reported for UK crops. A 6-week delay in sowing time halved grain yield in 1983; cutting in spring reduced yield by 40% in 1986. Grazing during winter did not significantly reduce yields. Results indicate that the development of wheat varieties adapted to the higher rainfall tablelands and suited to Australian marketing requirements might help to provide a useful alternative enterprise for tableland livestock producers.


2011 ◽  
Vol 176 (2-3) ◽  
pp. 145-150 ◽  
Author(s):  
Josephine Ng ◽  
Rongchang Yang ◽  
Suzie McCarthy ◽  
Cameron Gordon ◽  
Nawal Hijjawi ◽  
...  

2016 ◽  
Vol 8 (2) ◽  
pp. 565-569 ◽  
Author(s):  
Vikas Gupta ◽  
R. Selvakumar ◽  
Satish Kumar ◽  
C. N. Mishra ◽  
V. Tiwari ◽  
...  

Wheat production is globally weighed down by several biotic factors of which rusts and powdery mildew are the most important. Powdery mildew, caused by Blumeria graminis f. sp. tritici, is becoming a disease of major importance in the North Western Plains Zone and Northern Hills Zone of the country. In the present context ofclimate variability, diseases like powdery mildew can assume greater importance in wheat breeding programs. Importance of basic studies on powdery mildew is the need of hour. A set of 370 Indian bread wheat, durum, dicoccum and triticale varieties were screened using mixture of natural occurring pathotypes from four locations(viz., Karnal, Ludhiana, Dhaulakuan and Yamunanagar) under polyhouse conditions. Data were recorded on the severity of infection based on 0-9 scale. Out of 370, only 23 varieties (Amrut, DDK 1025, DWR 1006, DWR 195, GW 1139, HD 4672, HD 4530, HD 2278, HD 1981, DDK 1001, HI 8627, Jay, TL 2942, DT 46, K 8020, DDK 1029, K 9107, K 816, Lok 1, MACS 6145, DDK 1009, NP 111 and NP 200) had shown immune reaction (0) whereas 150, 83 and 114 varieties have shown resistance (1-3), moderately susceptible (4-6) and highly susceptible (>6) response respectively against powdery mildew. Data indicated that there is an urgent need to broaden the genetic base of wheat by identifying and introgressing new sources of powdery mildew resistance. With limited sources of PM resistance available, above identified genotypes can be further used and characterized for resistance breeding programs in India.


1990 ◽  
Vol 30 (2) ◽  
pp. 183 ◽  
Author(s):  
G Annison

The polysaccharide compositions of 20 wheat varieties from New South Wales and Western Australia were determined. Mean pentosan and �-glucan contents ranged from 5.7 1 to 8.18% and from 0.61 to 0.87% respectively, on a dry matter basis. Starch contents ranged from 61.5 to 68.9% and the wheat starches were between 21.1 and 31.8% amylose. The starch digestibility of the wheats was found to be independent of the levels or composition of the polysaccharides when assayed using 5-week-old broiler chickens.


2007 ◽  
Vol 56 (6) ◽  
pp. 819-823 ◽  
Author(s):  
Michael Watson ◽  
Maggie Brett ◽  
Mitchell Brown ◽  
Marianne G. Stewart ◽  
Shirley Warren ◽  
...  

The serotypes and molecular clones of penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) responsible for invasive pneumococcal disease (IPD) and discharging ears in metropolitan New South Wales were characterized to form a baseline prior to introduction of the heptavalent conjugate pneumococcal vaccine in Australia. Pneumococci isolated between 1 July 2000 and 30 June 2003 in Sydney from children <15 years were tested for antibiotic susceptibilities and serotyped. Penicillin-nonsusceptible pneumococci were typed by multilocus sequence typing and BOX PCR. During this period, 97 (13.9 %) of 698 pneumococci from IPD that were serotyped were penicillin-nonsusceptible. Of 607 pneumococci from discharging ears, 157 (26.1 %) were penicillin-nonsusceptible. Serotype 14 was the predominant serotype responsible for IPD and serotype 19F predominated from discharging ears. The heptavalent vaccine serotypes accounted for 613 (87.8 %) of all invasive isolates and 420 (69.8 %) of all isolates from discharging ears. Representatives of the major international clones were present among the PNSP. The majority of serotypes and clones that showed penicillin-nonsusceptibility are present within the vaccine. Serotype switching was also noted to have occurred prior to introduction of the vaccine. This study provides a characterization of the pneumococcal serotypes associated with IPD and discharging ears that will be useful for detecting potential selective effects of the vaccine. This surveillance should be continued, as it will be important to monitor the frequency and distribution of serotypes in the post-vaccine era.


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