Resistance of durum wheat cultivars to black point caused by Alternaria alternata

1980 ◽  
Vol 31 (6) ◽  
pp. 1097 ◽  
Author(s):  
RJ Southwell ◽  
PTW Wong ◽  
JF Brown

Resistance of durum wheat cultivars to black point caused by Alternaria alternata was evaluated in the field in northern New South Wales. The cultivars tested showed a range of infection levels. The most susceptible cultivars were Duramba and Gaza, while those showing the greatest resistance were Wandell, Wascana and aus 15350.

1985 ◽  
Vol 25 (4) ◽  
pp. 922 ◽  
Author(s):  
D Lemerle ◽  
AR Leys ◽  
RB Hinkley ◽  
JA Fisher

Twelve spring wheat cultivars were tested in southern New South Wales for their tolerances to the recommended rates and three times the recommended rates of trifluralin, pendimethalin, tri-allate and chlorsulfuron. Recommended rates of these herbicides did not affect the emergence or grain yield of any cultivar. However, differences between cultivars in their tolerances to trifluralin, pendimethalin and chlorsulfuron at three times the recommended rate were identified. The extent of the reduction in emergence and/or grain yield varied with herbicide and season, and there was also a herbicidexseason interaction. Durati, Songlen and Tincurrin were the most susceptible cultivars to trifluralin, and Teal was the most tolerant. Yield losses from trifluralin were more severe in 1979 than in 1980 or 1981. The differential between cultivars treated with pendimethalin was smaller and more variable; Tincurrin was the only cultivar with a yield reduction in more than one season. Durati, Songlen and Shortim were the only cultivars affected by chlorsulfuron. A reduction in crop emergence of a cultivar treated with trifluralin or pendimethalin did not correlate consistently with any grain yield loss, and reductions in emergence were always greater than yield loss.


1983 ◽  
Vol 34 (2) ◽  
pp. 99 ◽  
Author(s):  
BA Auld ◽  
DR Kemp ◽  
RW Medd

In four experiments, conducted over three contrasting seasons on the central western slopes of New South Wales, the grain yields of three wheat cultivars (Condor, Durati and Phoenix) sown in rhomboidal, square and rectangular patterns were compared with yields from traditionally sown (Poisson distribution along rows 180 mm apart) and broadcast arrangements. Square sowing resulted in significant (P < 0.05) yield increases (due to an increase in ear number) over rectangular arrangements in one experiment at three sowing densities 75,150 and 200 plants m-2. In two drier years there was no significant effect of arrangement at any density (40-400 plants m-2) in any one experiment. There was, however, a consistent significant (P < 0.05) trend over all experiments over 3 years, described by a response surface, of decreasing yield with increasing rectangularity as density was decreased. It is postulated that this was due to reduced ability of the plants to utilize available space. Traditional (sown in three seasons) and broadcast (sown in one season) arrangements produced yields which were not significantly (P > 0.05) different from the highest yielding treatments. It was concluded that there is no advantage in changing from the traditional sowing pattern to any precise geometric pattern. However, in precision sowing, rectangular patterns will result in lower yields than square patterns as density decreases from 200 plants m-2.


2003 ◽  
Vol 54 (3) ◽  
pp. 293 ◽  
Author(s):  
L. D. J. Penrose ◽  
N. A. Fettell ◽  
R. A. Richards ◽  
D. J. Carpenter

The aim of this study was to determine the effect of vernalisation on the field development of vernalisation responsive wheats in south-central New South Wales, and to develop equations with which to predict their timing of ear emergence in this region. To achieve this, a 'phasic development' approach was taken by considering relationships between temperature and photoperiod and the duration of the leaf, spikelet, and stem development phases in 3 photoperiod 'insensitive' vernalisation responsive wheat cultivars. The responsiveness to vernalisation of these cultivars covered much of the range that has been reported in wheat. This study was conducted at 3 sites and over 6 sowing times (17 field environments), covering the geographic and commercial range in sowing time for wheat grown in this region of Australia. An initial step in this study was to obtain measures of development duration that were independent of site and sowing date over our 17 field environments. Thus, appropriate photo-thermal units of time were sought using a photoperiod and vernalisation insensitive control wheat. The appropriate base temperatures and photoperiods we found for these photo-thermal units were not entirely consistent with those found in previous studies. Phase durations of our vernalisation responsive wheat cultivars were measured in these units.Vernalisation was found to be the predominant factor determining duration of both the leaf and spikelet phases in our vernalisation responsive wheat cultivars. The relationship we found between accumulated vernalisation and the duration of the leaf phase was similar to the relationship found in an earlier study in a controlled environment. This relationship differed from those currently used in 'phasic development' models for wheat. There appeared to be some latitude in the range of vernalising temperatures that could be used to estimate vernalisation in our field environments. Duration of the stem phase was strongly influenced by photoperiod, and showed greatest complexity of control, to the extent that site-specific effects could not be removed from equations predicting the duration of this phase.Simplified regression equations appeared to predict time of ear emergence reasonably well over the range of environments considered in our study, with the exception of a few cultivar × sowing time combinations for which wheat would not be commercially sown in the region. The ability to predict time of ear emergence may allow plant breeders to evaluate development controls that might extend the range of environments over which winter wheats may be commercially sown in south-central New South Wales.


2009 ◽  
Vol 49 (10) ◽  
pp. 769 ◽  
Author(s):  
K. G. McMullen ◽  
J. M. Virgona

In southern New South Wales, Australia, grazing wheat during the vegetative and early reproductive growth stages (typically during winter) can provide a valuable contribution of high quality feed during a period of low pasture growth. This paper reports results from a series of experiments investigating the agronomic management of grazed wheats in southern NSW. The effect of sowing date and grazing on dry matter production and subsequent grain yield of a range of wheat cultivars was measured in five experiments in 2004 and 2005. In all experiments, results were compared with ungrazed spring wheat (cv. Diamondbird). Grain yield of the best winter cultivar was either the same or significantly greater than the spring cultivar in each of the five experiments. Within the winter wheat cultivars, there was significant variation in grain yield, protein content and screenings, depending on site and year with the cultivar Marombi out-yielding all others. Interestingly, this cultivar usually had the least dry matter post-grazing but the greatest dry matter by anthesis of the winter wheats. Generally, if sowing of the winter wheat was delayed, then the effects on yield were small or non-existent. The results are discussed with respect to the benefits of incorporating grazing cereals into cropping programs in the medium rainfall zone of southern Australia.


1974 ◽  
Vol 14 (66) ◽  
pp. 93 ◽  
Author(s):  
AD Doyle ◽  
H Marcellos

The influence of variation in time of sowing on grain yield in five wheat cultivars has been studied in the North West Slopes of New South Wales over the period 1967 to 1971. Highest grain yields were obtained when wheat was sown at the end of June so as to flower at the end of the first week in October. Reductions in relative grain yield of 5 to 7 per cent were recorded for each week that sowing was delayed after the end of June, or 9 to 13.5 per cent for each week that flowering was delayed after the first week in October. Lower grain yields from late sown crops were associated with lower leaf area duration after flowering which could account for 69 per cent of the variation in grain yield. Lower grain yields in early sown crops were associated with lower ear numbers which could be ascribed in part to the influence of frosts.


2003 ◽  
Vol 32 (4) ◽  
pp. 465 ◽  
Author(s):  
R. J. Southwell ◽  
K. J. Moore ◽  
W. Manning ◽  
P. T. Hayman

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