The response of canola (Brassica napus L.) to tillage and fertiliser placement in contrasting environments in southern NSW

2003 ◽  
Vol 43 (11) ◽  
pp. 1323 ◽  
Author(s):  
P. J. Hocking ◽  
J. A. Mead ◽  
A. J. Good ◽  
S. M. Diffey

Land preparation for canola (oilseed rape; Brassica napus L.) by conventional cultivation can involve a number of workings, resulting in soil degradation and reduced crop growth. Minimum-tillage systems may help overcome these problems, but the placement of fertiliser at sowing must avoid chemical injury to germinating seed. The responses of canola cultivars to tillage and fertiliser placement were studied for 2 seasons at high (Breakfast Creek, 1997; Harden, 1998) and low (Ardlethan, 1997–98) rainfall sites. The tillage treatments were conventional cultivation, one-pass, and no-till (direct drill). The fertiliser treatments were 200 kg/ha 'starter' fertiliser (a�compound fertiliser supplying 30 kg N, 26 kg P and 22 kg S/ha) either placed with the seed, or broadcast, or banded to the side and 3 cm below the seed. In 1997 the canola was sown after wheat, and in 1998 after pasture. Plant establishment of all cultivars was reduced by 40–65% when fertiliser was placed with the seed; tillage treatment did not alter this response. Placing fertiliser with the seed reduced dry matter/m2 by up to 40% in plants at flowering, but by physiological maturity, there were no differences in dry matter/m2 due to fertiliser placement. Analysis of the combined seed yields for both years showed that although plants in the with-seed placement compensated by producing more seed/plant, this compensation was sufficient only at Breakfast Creek for yields to be comparable to those of the other fertiliser placements. Tillage had little effect on seed yields. In 1997, no-till yielded more than one-pass at Ardlethan, but in 1998 at Ardlethan no-till yielded less than the other tillage systems. Fertiliser placement and tillage had no effect on seed oil concentration and meal protein content. Cone penetrometer measurements (1998) showed no differences in soil strength between tillage treatments at Ardlethan; while at Harden, one-pass had less soil strength than the other tillage treatments. Crop water extraction was not affected by tillage at any site. It is concluded that a conservation-farming system involving no-till or one-pass tillage, and separation of seed and fertiliser has the potential for producing high yielding canola crops, reducing the risk of soil degradation, as well as saving time and land-preparation costs.

2012 ◽  
Vol 92 (1) ◽  
pp. 97-107
Author(s):  
Juliana J. Soroka ◽  
Larry F. Grenkow

Soroka, J. J. and L. F. Grenkow. 2012. When is fall feeding by flea beetles ( Phyllotreta spp., Coleoptera: Chrysomelidae) on canola ( Brassica napus L.) a problem? Can. J. Plant Sci. 92: 97–107. Two cultivars of Brassica napus canola were seeded in mid-May and early June in three field experiments in each of 3 yr near Saskatoon, Saskatchewan, to determine the effects of late-season flea beetle feeding on seed yields. In the first experiment, canola was sprayed with insecticide late in the summer to eliminate naturally-infesting flea beetles. In the second, 1×1×1.5 m screen cages were placed over early- and late-seeded canola at flowering and infested with flea beetles as canola matured. In the third investigation, sleeve cages were placed over individual plants and infested with 100 flea beetles. Flea beetles had no detrimental effects on early-seeded canola in any experiment, but did affect seed yields of late-seeded plots in some trials. Over two cultivars in 1 year, late-seeded plants in cube cages infested with about 350 flea beetles per plant when lower pods were turning from translucent to green in colour reduced yield by 241 kg ha−1 over control yields. Seed weights in these late-seeded plots were decreased from 2.68 g per 1000 seeds in uninfested cages to 2.44 g per 1000 seeds in infested cages. Populations of 100 flea beetles per plant in sleeve cages had no effect on harvest parameters in any seeding date or year.


2014 ◽  
Vol 94 (8) ◽  
pp. 1461-1469 ◽  
Author(s):  
Yun Ren ◽  
Jianfang Zhu ◽  
Nazim Hussain ◽  
Shanlin Ma ◽  
Genru Ye ◽  
...  

Ren, Y., Zhu, J., Hussain, N., Ma, S., Ye, G., Zhang, D. and Hua, S. 2014. Seedling age and quality upon transplanting affect seed yield of canola (Brassica napus L.). Can. J. Plant Sci. 94: 1461–1469. Seedling quality is an essential indicator for seed yield in canola, which is affected by many factors, including seedling age. Two field experiments were conducted to compare canola seedling quality and seed yield on 30-, 35-, 40-, 45-, 50-, 55-, and 60-d-old seedlings in 2011 and 2012. The relationship between seedling quality traits and seed yield of different seedling ages was also analyzed. Results revealed that the highest seed yield obtained from 40-d-old seedlings was attributed to more branches and siliques per plant. The negative effect of young seedlings (30-d-old) on seed yield was greater than that of old seedlings (60-d-old). The reduction rates in seed yield on the 30- and 60-d-old seedlings were 25.7 and 18.2%, respectively, compared with the 40-d-old seedlings. Increased root neck diameter, green leaf number, shoot, and root dry matter was the case on 40-d-old seedling transplanted plants compared with other ages. However, the increase was larger in the old seedlings than in the young seedlings. On average, the shoot and root dry weights of the 30-d-old seedlings were 1.9 and 1.7% of those in the 60-d-old seedlings. However, correlation analysis revealed that the seedlings with the highest shoot and root dry matter did not necessarily obtain the highest seed yield. Factor analysis suggested that the effects of root neck diameter and green leaf number on seed yield were more pronounced than those of shoot and root dry matter. Therefore, high seed yield in canola could be defined in terms of optimum green leaf numbers and branches per plant.


Botany ◽  
2013 ◽  
Vol 91 (6) ◽  
pp. 414-419 ◽  
Author(s):  
Limin Wu ◽  
Aliaa El-Mezawy ◽  
Saleh Shah

To provide effective and specific native promoters for canola (Brassica napus L.) genetic modification, three promoters were isolated by genome walking from this species. These three promoters were fused to the uidA reporter gene (GUS) and were independently used to generate populations of transgenic canola plants. Plants transformed with BnPGPro-GUS (B. napus putative germin promoter) exhibited GUS activity in all the tissues tested at a level comparable to those transformed with CaMV35 S promoter. This indicates that BnPGPro may serve as a native constitutive promoter for canola. The other two promoters, BnPro3-GUS and BnPro5-GUS (B. napus, promoter 3 and 5), exhibited GUS activity in various tissues. None of these two promoters expressed in embryo, however. These novel Brassica native promoters can be used to modify canola genes for various purposes.


2008 ◽  
Vol 59 (6) ◽  
pp. 578 ◽  
Author(s):  
J. L. Jacobs ◽  
G. N. Ward ◽  
Gavin Kearney

In southern Australia, the majority of dry land dairy farms use a 2-pond system to treat and contain dairy effluent collected at the milking platform. This effluent contains a range of nutrients that have the potential to affect forage dry matter (DM) yields, nutritive characteristics, and mineral content of forages. The effect of applying second-pond dairy effluent to the summer-active forages chicory (Chichorium intybus L. cv. Grouse), Hunter (Brassica campestris L. × Brassica napus L.), Winfred (Brassica napus L.), and Sweet Jumbo (Sorghum bicolor (L.) Moench × Sorghum sudanese (Piper) Stapf.) over two summer periods was measured. Effluent was applied at rates of 0, 40, 80, and 100 mm with application split into two equal application times. The first occurred 6–10 weeks after sowing and the second immediately after the first grazing. Forages were assessed for DM yield, nutritive characteristics, and mineral content over the two growth periods in each year. Analysis of effluent showed that on average over the 2 years, the effluent contained 146, 34, 439, and 18 kg/ML of nitrogen (N), phosphorus (P), potassium (K), and sulfur (S), respectively. Furthermore, the effluent also contained 161 kg/ML of calcium (Ca) and 222 kg/ML of magnesium (Mg). For the total growth period in Year 1, all crops showed a linear increase (P < 0.05) in DM yield to applied effluent, with response values varying for each crop. Responses were 49, 52, 29, and 51 kg DM/ha.mm applied effluent for chicory, Hunter, Sweet Jumbo, and Winfred, respectively. For Year 2, all crops also showed a linear increase (P < 0.05) in DM yield (15 kg DM/ha.mm applied effluent) with applied effluent. In Year 1, crude protein (CP) content of all crops increased (P < 0.05) in a linear manner at rates of 0.073 and 0.047% per mm applied effluent for growth periods 1 and 2. There were also linear responses (P < 0.05) in Year 2, with responses varying for each crop for each growth period. For chicory there was no effect of effluent application on CP content in either growth period, while other crops generally exhibited a linear increase with responses of up to 0.08% per mm applied effluent. The greatest changes in mineral content of herbage were those of K, Ca, and Mg. There was a linear increase (P < 0.05) in K content for all growth periods in Years 1 and 2. Magnesium content of chicory (periods 1 and 2) and Winfred (period 2) showed a linear decrease (P < 0.05) in response to effluent application in Year 1, whereas there was no effect in Year 2 for any crops. The results from this study highlight the potential of second-pond dairy effluent to increase DM yields of a range of summer-active forage crops. The data also suggest that while effluent can improve DM yields when soil moisture is limiting, when additional moisture as rainfall occurs, responses from effluent are even more pronounced. In addition, the CP content of forages can be improved when effluent is applied. The combination of increased DM yield with higher CP content provides greater flexibility in dairy cattle feeding options through the dry summer period.


2013 ◽  
Vol 64 (2) ◽  
pp. 115 ◽  
Author(s):  
A. N. Papantoniou ◽  
J. T. Tsialtas ◽  
D. K. Papakosta

For crops grown in Mediterranean environments, translocation of pre-anthesis assimilates to the fruit is of great importance, because hot and dry conditions during fruit ripening diminish net assimilation rate and nitrogen (N) uptake. This field study was conducted to assess the pattern of dry matter and N accumulation and the role of assimilate translocation in pod development of oilseed rape plants in a Mediterranean environment. Four cultivars of winter oilseed rape (Brassica napus L.), i.e. three hybrids (Royal, Exact, Excalibur) and an inbred line (Fortis), were grown for two growing seasons (2005–06 and 2006–07) in northern Greece. On average, 581, 1247, 1609, and 2749 growing degree-days (GDD) were required for six leaves, stem elongation, 50% anthesis in main stem, and physiological maturity in the first year, and 539, 1085, 1601, and 2728 GDD in the second year. The R2 of the modified Richards function indicated that aboveground biomass and N accumulation were described with high approximation efficacy. The across-cultivars genotype mean maximum predicted total aboveground dry matter and N content were 1368.8 and 21.4 g m–2 in 2006 and 1655.1 and 25.4 g m–2 in 2007. In 2007, dry matter and N translocation from vegetative tissues to pods were 464.4 and 21.0 g m–2, and significantly higher than the corresponding values recorded in 2006 (264.4 and 17.0 g m–2). These differences were due to greater amounts of dry matter and N accumulating at anthesis and the greater sink capacity of plants (pod number) in 2007. The fact that pod development occurred in a period when N accumulation by oilseed rape plants had stopped led to high values of contribution of pre-anthesis N accumulation to pod N content in both years (92.8% in 2006 and 96.6% in 2007). Results indicated that hot and dry weather post anthesis reduced dramatically the net assimilation rates; thus, translocation of pre-anthesis assimilates was crucial for pod development. The results demonstrate that variation in weather conditions between growing seasons is one of the main causes of seasonal variation in oilseed rape productivity under Mediterranean conditions.


1989 ◽  
Vol 69 (4) ◽  
pp. 1101-1111 ◽  
Author(s):  
E. J. DEIBERT ◽  
R. A. UTTER

A field study was conducted during 1985–1987 on a Fargo clay soil to evaluate growth, and NPK content at beginning flowering, pod fill, and mature seed at harvest of an early- (McCall) and a late-maturity (Dawson) soybean (Glycine max (L.) Merr.) cultivar as influenced by conventional (plow) or reduced (sweep, intertill, no-till) tillage systems and weed control methods. Excellent seed emergence was obtained on all tillage systems. Fall application of granular herbicide provided excellent weed control but herbicide plus cultivation caused reduced plant growth. Tillage system did not significantly affect plant and seed dry matter production. Yearly differences in dry matter production between early- and late-maturity cultivars depended on precipitation distribution. N and P uptake at pod fill was equal to seed uptake while K in the seed was one-half that measured at pod fill. Stratification of P and K in the surface soil profile of the reduced tillage systems was not detrimental and possibly enhanced early growth when root development was not extensive. Plants exhibited chlorosis on only the plow system under wet soil conditions indicating improved internal drainage under the reduced tillage systems. Interactions of climate with tillage system and cultivar maturity were more pronounced in this soybean study than previously reported which may be related to the cool, dry northern area.Key words: Soybean, no-till, zero-till, weed control, plant nutrients, cultivars, soil nutrient stratification


2020 ◽  
Vol 8 (4) ◽  
pp. 400-409
Author(s):  
A. K. M. Aminul Islam ◽  
F. M. Era ◽  
N. K. Aminul Chowdhury

Forty four testcross progenies obtained from crossing between five CMS and forty one candidate lines were evaluated both in field and laboratory condition to identify candidate restorer line(s). Nineteen testcross progenies were recorded as fully fertile with 100% plant fertility by counting the number of fertile plants from the total number of plants per lines. On the other hand from pollen fertility test, 11 testcross progenies [206A × 001(6), 9905A × 030(2), 9905A × 027(6) (0.57), 206A × 37(1) (0.68), 9904A × 027(4) (0.83), 248A × 020(6) (1.08), 248A × 018 (1.12), 248A × 022 (1.13), 248A × 017 (1.58), 248A × 038(2) (1.96) and 248A × 001(6) (2.02)] were found with 0-2.02% pollen sterility that could be mentioned as fertile or restorer lines for making hybrids. Agronomic performances were also satisfactory for these selected test cross progenies. The genotype 248A × 017 took the shortest time (30.00) for first flowering as well as ripening followed by 248A × 007(1). The highest number of pods per plant was observed in the testcross progeny 248A × 022 (649.59) and the highest number of seeds per pod (30.33) in 248A × 020(6). For seed weight per plant, 206A × 001(6) was recorded with maximum value (0.08g) while the lowest (23.33) number of seeds per plant was found in this progeny. In case of seed yield per plant, 248A × 022 gave the highest yield (30.30). The seed yield of the progenies 248A × 017 (23.49), 9905A × 027(6) (20.39), 248A × 001(6) (17.26), 9904A × 027(4) (17.02) and 248A × 038(2) (16.53) were also in the highest level.


Author(s):  
Necda Çankaya ◽  
Ulviye Kumova

This research was carried out in 2011 and 2012 in order to determine the flowering phenology, number of flowers, nectar and pollen potential in the Samsun province of the oilseed rape (Brassica napus L.), which is widely used in agriculture in our country. In the first year of the study (2011), it was determined that the rapeseed plant was in flower for 44 days, there were 2.694 flowers per plant, 1.89 kg/da nectar per day and 1330 kg/da pollen production. In the second year of the research (2012), it was revealed that the rapeseed plant was in flower for 39 days, there were 701 plants/flower in the plant, 0.38 kg/da nectar secreted daily and 331.57 kg/da pollen. According to the results of two years, the yield of rapeseed was found to be 41.5 days, the daily nectar production was 0.23 mg/flower/day, the nectar dry matter level was 20.25% and the pollen production was 0.48 mg/flower/day. In Samsun province, it was determined that rapeseed plants flowered before the flowering of many plants in the vicinity in the early spring, and provided honey bees, Apis mellifera L., and many other honey bees, nectar and pollen. It has been demonstrated that the cultivation of rapeseed is cultivated in the early spring, and it can be a convenient source of food for honey bees and other dusty insects.


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