Growth, recovery, and yield of dual-purpose canola (Brassica napus) in the medium-rainfall zone of south-eastern Australia

2012 ◽  
Vol 63 (7) ◽  
pp. 635 ◽  
Author(s):  
Jeffrey I. McCormick ◽  
Jim M. Virgona ◽  
John A. Kirkegaard

The effect of grazing of vegetative canola (Brassica napus) with sheep on crop growth and yield was investigated in two field experiments (Expts 1 and 2) in 2008 at Wagga Wagga, New South Wales, Australia. The experiments included a range of cultivars, sowing rates, and grazing periods to investigate the influence of these factors on grazing biomass, crop recovery, and grain yield. Three spring canola cultivars (representing triazine-tolerant, conventional, and hybrid types) were used in both experiments and were sown at three sowing rates and grazed by sheep for 7 days in midwinter in Expt 1, while two different grazing periods were compared in Expt 2. Supplementary irrigation was applied to Expt 1 to approximate average growing season conditions, while Expt 2 received no irrigation. Increased sowing rate produced greater early shoot biomass for grazing, but the-triazine tolerant cultivar produced less biomass than the conventional or hybrid cultivars in both experiments. Grazing reduced dry matter and leaf area by >50%, delayed flowering by 4 days on average, and reduced biomass at flowering by 22–52%. However, there was no impact of cultivar or sowing rate on the recovery of biomass and leaf area after grazing. Grazing had no effect on final grain yield under supplementary irrigation in Expt 1, but reduced grain yield under the drier regrowth conditions in Expt 2. The results demonstrate that grazing canola is feasible under average seasonal conditions in a medium-rainfall environment (400–600 mm) without yield penalty, provided the timing and intensity of grazing are matched to available biomass and anticipated seasonal water supply to support grain production. More broadly, we suggest that grain yield reductions from grazing could be avoided if suitable conditions for regrowth (residual dry matter, length of regrowth period, and adequate moisture) can generate biomass levels in excess of a target value of ~5000 kg ha–1 at flowering. This target value represents a biomass level where >90% of photosynthetically active radiation was intercepted in our study, and in other studies represents a biomass level above which there is little further increase in potential yield. Such a target provides a basis for more objective grazing management but awaits further confirmation with experimentation and modelling.

1982 ◽  
Vol 22 (115) ◽  
pp. 76 ◽  
Author(s):  
KA Boundy ◽  
TG Reeves ◽  
HD Brooke

The effect of serial planting on dry matter production, leaf area, grain yield and yield components cf Lupinus angustifoiius (cvv. Uniwhite, Uniharvest and Unicrop) and L. albus (cv. Ultra) was investigated in field plots at Rutherglen in 1973 and 1974. Delayed planting reduced dry matter production of all cultivars, and leaf area for Ultra. Differences in dry matter partitioning were observed between the late flowering Uniharvest, and the early flowering Unicrop and Ultra. In Uniharvest, delayed plantings resulted in a greater proportion of total dry matter being produced during the flowering phase, whereas the reverse was true for Unicrop and Ultra. The later flowering cultivars showed marked grain yield and yield component reduction with later sowing. Yields were reduced by 160.6 kg/ha and 222.5 kg/ha for each week's delay in sowing Uniharvest and Uniwhite, respectively. This effect was offset in the early flowering cultivars by greater development of lateral branches. In addition, when Unicrop and Ultra were planted in April, pod and flower abortion on the main stem resulted from low temperatures at flowering time. Optimum sowing time was early April for Uniwhite and Uniharvest, and early May for Unicrop and Ultra. Excellent vegetative growth under ideal moisture conditions highlighted the poor harvest indices of lupins and the scope for genetic improvement in the genus.


2012 ◽  
Vol 63 (1) ◽  
pp. 17 ◽  
Author(s):  
Penny Riffkin ◽  
Trent Potter ◽  
Gavin Kearney

Area and production of canola (Brassica napus L.) in the High Rainfall Zone (HRZ) of southern Australia has increased significantly over the past decade. Varieties available to growers have not been bred specifically for the HRZ and are generally adapted to the drier regions of the cropping belt. Field experiments were conducted at Hamilton in south-west Victoria in 2005, 2006 and 2008 to identify canola traits and management suited to the HRZ of southern Australia. Nine varieties with different reported maturities (winter and spring types) were sown at either two times of sowing and/or under different nitrogen (N) fertiliser regimes. Dates of key phenological development were recorded, dry matter was determined at bud, flowering and maturity and grain yield and yield components were determined at harvest. Plant traits and climate data were assessed in relation to grain yield. Yields of the winter types were either significantly (P < 0.05) greater or not significantly less than the spring types in all 3 years and similar to those reported under experimental conditions in Europe. This was despite the winter types flowering up to 35 days later than the spring types and spring rainfall being approximately half that of the long-term average. In general, the winter types had greater early vigour, greater dry matter production at the bud, flowering and maturity stages and were taller than the spring types. Regression analysis showed positive relationships between grain yield and pod density and plant size (dry matter and plant height). Plant size was influenced by variety, time of sowing and N fertiliser application rates. Crops in the HRZ were able to sustain more seeds per pod at larger canopy sizes and pod densities than those achieved in the northern hemisphere. Despite the number of pods per g of dry matter at flowering being nearly double that reported in the UK, there was little apparent reduction in the number of seeds per pod. It is possible that higher solar radiation and warmer minimum temperatures in the HRZ of Australia provide conditions more favourable for growth before, and during grainfill. This indicates that different dry matter production and yield component targets may be appropriate for canola in this environment especially in more typical seasons. It is likely that growers will need to sow new, later maturing varieties earlier and with higher rates of N fertiliser than is current practice in Australia. This study indicates that winter types may have the potential to provide improvements to the yield of canola in the HRZ either through the direct importation of varieties from overseas or through the identification and incorporation of desired traits into existing material. It is recommended that a wider range of germplasm be assessed over a greater geographical area to identify traits and management practices to optimise phenology and canopy structure. This information can be used to help inform breeders on crop improvement priorities as well providing tailored management practices to maximise grain yields for this environment.


2021 ◽  
Vol 12 (5) ◽  
pp. 594-602
Author(s):  
L. Rana ◽  
◽  
H. Banerjee ◽  
D. Mazumdar ◽  
S. Sarkar ◽  
...  

The field experiments were conducted at farmer’s field, Madandanga village under Chakdaha Block of Nadia district in West Bengal during rabi season 2014-15 and 2015-16. Treatments were distributed in split-factorial design, with three varieties (P ‘3533’, P ‘3396’, P ‘30V92’) in the main plot and three planting density (55,555, 66,666, 83,333 plants ha-1) × three sowing dates (November 20, November 30, December 10) combinations in the sub-plots, replicated thrice. Irrespective of planting density and sowing date, the variety ‘P30V92’ produced the highest yield, followed by ‘P3396’ and ‘P3533’. The significantly highest grain and stover yield was obtained in high density planting (83,333 plants ha-1), accounting 44.2 and 39.6% more than low planting density (55,555 plants ha-1), respectively. The maximum grain and stover yields were obtained from Nov. 20 sown plants; being 7.71 and 11.95% more than the grain yield derived from late sown (Dec. 10) plants. A correlation study showed that among the growth and yield components, leaf area index (0.96) and shelling percentage (0.91) exhibited highly positive direct effects on the grain yield of hybrid maize. However, other growth attributes, namely P uptake (0.88), K uptake (0.86) and plant height (0.81) exerted comparatively low positive direct effects on the grain yield of hybrid maize. Further, the standard regression equation revealed a significant relationship of shelling percentage (p≤0.01), leaf area index (p≤0.01) and uptake of P (p≤0.05) with grain yield.


2010 ◽  
Vol 61 (1) ◽  
pp. 50 ◽  
Author(s):  
S. J. Sprague ◽  
J. A. Kirkegaard ◽  
B. J. Howlett ◽  
J. Graham

Leptosphaeria maculans causes blackleg of Brassica napus (canola), manifesting in symptoms including leaf lesions, stem canker, and root rot. Root rot is an extension of the stem canker phase of the disease resulting from foliar infection; however, the role of root rot in grain yield loss has not been investigated. Field experiments were conducted in south-eastern Australia to determine the efficacy of fungicides and host resistance to stem canker for the control of root rot, along with the association between root rot severity and grain yield. Fungicides applied as a seed dressing (fluquinconazole) or coated on fertiliser (flutriafol) reduced root rot severity by 16 and 41%, respectively. Root rot severity was 78% less in a B. napus cultivar with an Australian Blackleg Rating (ABR) of 9.0 (highly resistant to stem canker) than in a moderately resistant cultivar (ABR 5.5), and was also reduced in Brassica species with good resistance to stem canker. Root rot caused little or no additional reduction in yield or harvest index of individual B. napus plants above that caused by stem canker. Individual upright plants with greater than 80% of the stem cross-section blackened had significantly reduced seed yield; however, this was influenced by rainfall during the grain-filling period. This study shows that current management strategies for stem canker caused by L. maculans also control root rot in B. napus, as although the symptoms in roots are severe, these symptoms have no additional effect on yield.


1979 ◽  
Vol 19 (100) ◽  
pp. 554 ◽  
Author(s):  
JL Cooper

A semi-dwarf cultivar (WW 15) and a standard height Australian wheat variety (Timgalen) were grown at two nitrogen levels and under three irrigation regimes in the Murrumbidgee Irrigation Area. Numerous plant measurements were taken to determine which attributes were associated with the superior yield of semi-dwarf wheat in this environment. WW 15 yielded 42% more grain than Timgalen and nitrogen fertilizer increased the yield of both varieties. The irrigation treatments did not affect yield because rainfall was above average. Total dry matter production and leaf area of WW 15 were similar to those of Timgalen, but WW 15 put a much greater proportion of its dry matter into grain. A greater number of grains per spike was the yield component responsible for the higher yield of WW 15. The increase in grain yield with the addition of nitrogen fertilizer was due to a general improvement in all aspects of crop vigour (e.g. tiller density, leaf area, total dry matter). There was no interaction between cultivars and nitrogen rates in their effect on grain yield.


2010 ◽  
pp. 30-34
Author(s):  
MS Islam ◽  
MSU Bhuiya

Pot experiments were conducted in net house during Boro 2002 and 2003 at Bangladesh Rice Research Institute (BRRI) to compare the growth and yield of hybrid and inbred rice varieties under controlled condition. Hybrid variety Sonarbangla-1 and BRRI hybrid dhan1 and inbred modern variety BRRI dhan29 were used in both the years. During Boro 2002, Sonarbangla-1 and BRRI hybrid dhan1 had higher plant height and tillers hill-1 compared to BRRI dhan29. The largest leaf area of 75cm2 hill-1 was recorded in BRRI hybrid dhan1 at 30 DAT but at 60 and 90 DAT, Sonarbangla-1 had the highest leaf area of 723 and 1406 cm2 hill-1, respectively. The highest shoot dry matter production was recorded in BRRI hybrid dhan1 at 30 DAT but in Sonarbangla-1 at 60 and 90 DAT. Rooting depth and root dry weight of Sonarbangla-1 were 15- 20% higher than those of BRRI hybrid dhan1 and BRRI dhan29. At harvest, the largest number of panicles hill-1 was observed in BRRI dhan29 followed by Sonarbangla-1. The number of grains panicle-1, 1000-grain weight and grain yield were higher in Sonarbangla-1 followed by BRRI dhan29. During Boro 2003, highest plant height, number of tillers hill-1, leaf area and shoot dry matter were recorded in BRRI hybrid dhan1 at all DAT, followed by Sonarbangla-1 in most cases. Rooting depth and root dry weight were the highest in Sonarbangla-1 followed by BRRI hybrid dhan1. At harvest, highest number of panicles hill-1 were observed in BRRI dhan29 and Sonarbangla-1 but BRRI hybrid dhan1 had the highest number of grains panicle-1. Sonarbangla-1 had the highest 1000-grain weight and grain yield.


1973 ◽  
Vol 81 (1) ◽  
pp. 131-138 ◽  
Author(s):  
B. A. C. Enyi

SummaryIn soya beans (var. 3H55F4/149/1) grown in Tanzania, the total dry matter per plant, pod weight/stem weight, shelling percentage, number of nodes per plant, number of pods per plant, percentage number of nodes with pods, number of filled pods per plant, number of branches per plant, and grain weight from side branches decreased with increase in plant density from 74 to 111, 222, and 444 thousand plants per hectare. Grain yield per hectare decreased by 38, 51, and 72% respectively with the increases in plant population, but yield of total dry matter per hectare showed a significant increase with density. Crop growth rate increased with increasing leaf area, which in turn increased with increasing plant density. Relative growth rate, however, decreased with rising population. Over the range of the densities studied grain yield was positively related to number of side branches but negatively related to dry-matter production, leaf area duration and percentage of light intercepted. The proportion of dry matter accumulated in the pods and side branches decreased with increase in population, whereas the proportion accumulated in the main stem increased. Light seems to be the major factor controlling grain yield in this variety of soya bean, low light intensity under the plant leading to a reduction in the number of side branches, number of pods per plant and number of nodes with pods.


2017 ◽  
Vol 38 (4Supl1) ◽  
pp. 2387
Author(s):  
Santiel Alves Vieira Neto ◽  
Fábio Ribeiro Pires ◽  
João Carlos Madalão ◽  
Douglas Gomes Viana ◽  
Carlos César Evangelista de Menezes ◽  
...  

Given the high costs of agricultural production, especially due to the price of fertilisers, particularly nitrogen, the use of inoculants to supply nitrogen to soybean crops is a widely recommended practice. The objective of this study was to evaluate the feasibility of applying inoculants through seed and planting furrow in soil previously cultivated with soybean and Brazilian native “cerrado” biome soil under greenhouse conditions. Seven treatments were tested: 1) inoculation via seed (inoculant + fungicide + micronutrient), 2) treatment via seed (fungicide + micronutrient), 3) control (only seed), 4) inoculation via furrow-dose 1 (recommended dose), 5) inoculation via furrow-dose 2 (twice the recommended dose), 6) inoculation via furrow-dose 3 (three times the recommended dose) and 7) inoculation via furrow-dose 1 + seed inoculation. We evaluated plant height, fresh and dry matter weight of the aerial part and nodules, number of total, viable and non-viable nodules, number of pods per plant and grain yield. Inoculation was more effective when used in cerrado soil, but soybean performance in treatments without inoculation was higher in previously cultivated soil. Application through furrow proved to be a viable practice due to the similarity of the results obtained with the traditional application by seed.


1991 ◽  
Vol 18 (1) ◽  
pp. 53 ◽  
Author(s):  
PC Pheloung ◽  
KHM Siddique

Field experiments were conducted in the eastern wheat belt of Western Australia in a dry year with and without irrigation (1987) and in a wet year (1988), comparing three cultivars of wheat differing in height and yield potential. The aim of the study was to determine the contribution of remobilisable stem dry matter to grain dry matter under different water regimes in old and modern wheats. Stem non-structural carbohydrate was labelled with 14C 1 day after anthesis and the activity and weight of this pool and the grain was measured at 2, 18 and 58 days after anthesis. Gutha and Kulin, modern tall and semi-dwarf cultivars respectively, yielded higher than Gamenya, a tall older cultivar in all conditions, but the percentage reduction in yield under water stress was greater for the modern cultivars (41, 34 and 23%). In the grain of Gamenya, the increase in 14C activity after the initial labelling was highest under water stress. Generally, loss of 14C activity from the non-structural stem dry matter was less than the increase in grain activity under water stress but similar to or greater than grain activity increase under well watered conditions. Averaged over environments and cultivars, non-structural dry matter stored in the stem contributed at least 20% of the grain dry matter.


2015 ◽  
Vol 66 (4) ◽  
pp. 308 ◽  
Author(s):  
Alison. J. Frischke ◽  
James R. Hunt ◽  
Dannielle K. McMillan ◽  
Claire J. Browne

In the Mallee region of north-western Victoria, Australia, there is very little grazing of crops that are intended for grain production. The success of dual-purpose crops in other regions in south-eastern Australia with higher and more evenly distributed rainfall has driven interest in assessing the performance of dual-purpose cereals in the region. Five experiments were established in five consecutive years (2009–13) in the southern Mallee to measure the forage production and grain yield and quality response in wheat and barley to grazing by sheep or mechanical defoliation. The first three experiments focused on spring cultivars sown from late April to June, and the last two on winter cultivars planted from late February to early March. Cereal crops provided early and nutritious feed for livestock, with earlier sowing increasing the amount of dry matter available for winter grazing, and barley consistently produced more dry matter at the time of grazing or defoliation than wheat. However, the grain-production response of cereals to grazing or defoliation was variable and unpredictable. Effects on yield varied from –0.7 to +0.6 t/ha, with most site × year × cultivar combinations neutral (23) or negative (14), and few positive (2). Changes in grain protein were generally consistent with yield dilution effects. Defoliation increased the percentage of screenings (grains passing a 2-mm sieve) in three of five experiments. Given the risk of reduced grain yield and quality found in this study, and the importance of grain income in determining farm profitability in the region, it is unlikely that dual-purpose use of current cereal cultivars will become widespread under existing grazing management guidelines for dual-purpose crops (i.e. that cereal crops can be safely grazed once anchored, until Zadoks growth stage Z30, without grain yield penalty). It was demonstrated that early-sown winter wheat cultivars could produce more dry matter for grazing (0.4–0.5 t/ha) than later sown spring wheat and barley cultivars popular in the region (0.03–0.21 t/ha), and development of regionally adapted winter cultivars may facilitate adoption of dual-purpose cereals on mixed farms.


Sign in / Sign up

Export Citation Format

Share Document