Prognosis of boron deficiency in oilseed rape (Brassica napus) by plant analysis

1998 ◽  
Vol 49 (5) ◽  
pp. 867 ◽  
Author(s):  
Youzhang Wei ◽  
R. W. Bell ◽  
Yuai Yang ◽  
Zhengqian Ye ◽  
Ke Wang ◽  
...  

In areas where soils are low in boron (B), the ability to predict B deficiency by plant analysis depends on the development of calibrated standards and offers the potential of preventing or minimising losses in seed yield. The present study aimed at establishing relationships between seed yield in winter oilseed rape (Brassica napus) and B concentrations in defined leaves during growth before fiowering and from them to determine critical values for the prognosis of B deficiency. Oilseed rape cv. Zheyouyou 2 was grown in 10 field experiments in Zhejiang province, south-east China, with B rates from 0 to 3· 3 kg/ha. At 4 of the sites, oilseed rape was resown in the following year to assess seasonal effects on critical concentrations. Experiments were conducted on the 3 main soil groups on which oilseed rape is grown in south-east China. The youngest open leaf (YOL) was selected as the sampling part because its B concentrations were strongly responsive to increasing B supply and well correlated with seed yield response. In this study, the best model of the relationship between YOL B concentration and yield was the Mitscherlich equation, which explained 68-89% of the variation in the data. The calculated critical range in the YOL at seedling stage was 20-25 mg B/kg and appeared to be valid in 2 seasons and on 3 soil types. The critical B range for prognosis of B deficiency was found to predict consistently those crops in farmers" fields that had low seed yield and low soil B, but needs to be evaluated in other growing environments especially those for spring rape.

2003 ◽  
Vol 141 (2) ◽  
pp. 231-240 ◽  
Author(s):  
P. J. W. LUTMAN ◽  
S. E. FREEMAN ◽  
C. PEKRUN

The present paper reports on three sets of experiments exploring the persistence of seeds of oilseed rape (Brassica napus). The first, where known numbers of seeds were buried in September 1991 in two field experiments, demonstrated substantial initial losses of seeds, such that only 0·2 and 3·8% of seeds were still present after 4 months. In these experiments, which were not disturbed by mechanical cultivation, there was little evidence of further decline over the following 13 months. In the second of the two experiments, seeds were then left undisturbed for a further 136 months. A mean of 1·8% of seeds were still present after this period, providing further confirmation of the lack of decline in seed numbers in these undisturbed conditions. In the second pair of experiments, known numbers of seeds of three rape cultivars were broadcast onto plots and then either ploughed into the soil immediately after the start of the experiments, or were exposed to weekly shallow tine cultivation followed by ploughing after 4 weeks. The former created a larger seedbank than the latter. The experiments were then ploughed, annually (Expt 1) or at less frequent intervals (Expt 2); appreciable numbers of seeds survived for 65 months in both. Calculations based on exponential decline curves indicated that 95% seed loss would take 15–39 months, depending on the site, cultivar and initial post-harvest stubble treatment. The third part of the paper is based on more detailed studies of persistence of seeds of six cultivars in Petri dishes and buried in 25 cm pots. This work confirmed that cultivars differed in their persistence, as Apex was confirmed as highly persistent, whereas Rebel was short-lived. There were inconsistencies in the response of cultivar Synergy between the Petri-dish and pot experiment, which need further study. This experiment also reinforced the conclusion of the initial field experiments that little seed loss occurs in the absence of cultivations. Appreciable numbers of rape seeds will persist up to 4 years, in normal cropping conditions and in the absence of cultivation one experiment has confirmed persistence for over 11 years.


2021 ◽  
Vol 66 (1) ◽  
pp. 17-25
Author(s):  
Valiollah Rameeh ◽  
Maryam Niakan ◽  
Mohammad Mohammadi

The effects of four sulphur levels: S0, S1, S2 and S3, including 0, 12, 24 and 36 kg S ha-1, respectively, along with 115 kg N ha-1 were studied on yield-related traits of oilseed rape (Brassica napus L.). The significant variance of treatments was determined for plant height, yield component characters, seed yield and oil content. The sulphur application significantly increased most of the traits compared to the S0 level. The S3 (36 kg S ha-1) treatment led to the highest mean value of plant height (132 cm) which was classified with S2 (24 kg S ha-1) in the same statistical group. Sulphur had an increasing effect on pods per plant, and it ranged from 92 to 196 for S0 and S3 applications, respectively. S0 and S1 with 92 and 121 pods per plant were grouped in the same statistical group. In addition, S2, and S3 with 165 and 196 pods per plant showed no significant statistical difference. The sulphur application significantly increased seed yield compared to control (S0 level), and it ranged from 2744 to 3215 kg ha-1 in S0 and S3, respectively. The average oil contents of 45.69, 46.96, 47.46 and 49.53 % were detected for 0, 12, 24 and 36 kg S ha-1, respectively.


2013 ◽  
Vol 153 (1) ◽  
pp. 42-55 ◽  
Author(s):  
C. A. WHITE ◽  
S. E. ROQUES ◽  
P. M. BERRY

SUMMARYThe aim of the present study was to evaluate the effects on yield, oil concentration and nitrogen (N) uptake efficiency of N fertilizer applied to the foliage of oilseed rape during and soon after flowering. Four field experiments were conducted in the UK during the 2008/09 and 2009/10 seasons which investigated six rates of soil-applied N (ammonium nitrate) ranging from 0 to 280 or 320 kg N/ha with each treatment followed by 0 or 40 kg/ha of foliar N applied as a solution of urea at the end of flowering. Each experiment also investigated five rates of foliar N ranging from 0 to 120 kg N/ha applied at the end of flowering and five timings of foliar N (40 kg N/ha) from mid-flowering to 2 weeks after the end of flowering.Foliar N at 40 kg N/ha applied at the end of flowering significantly increased the seed yield in three of the four experiments. The seed yield increase across all four experiments was 0·25 t/ha (range of 0–0·41 t/ha). In two experiments, the increase in seed yield in response to foliar N occurred irrespective of whether it followed sub-optimal or super-optimal rates of soil-applied N; in one experiment there was a greater response at sub-optimal soil-applied N rates. The foliar N treatment reduced the seed oil concentration by 11 g/kg and increased seed protein concentration by 11 g/kg. Similar yield responses were observed for foliar N applications between mid-flowering and 2 weeks after the end of flowering. The efficiency with which foliar N was taken up into the plant varied between 0 and 100% with an average uptake efficiency across the four experiments of 61%.


Euphytica ◽  
2010 ◽  
Vol 175 (2) ◽  
pp. 161-174 ◽  
Author(s):  
Gang Chen ◽  
Jianfeng Geng ◽  
Mukhlesur Rahman ◽  
Xueping Liu ◽  
Jingxing Tu ◽  
...  

Euphytica ◽  
2019 ◽  
Vol 215 (10) ◽  
Author(s):  
Joanna Wolko ◽  
Agnieszka Dobrzycka ◽  
Jan Bocianowski ◽  
Iwona Bartkowiak-Broda

Abstract Rapeseed breeding programs are focused mainly on improving plant potential and seed yield. One of the ways to improve seed yield in oilseed rape is heterosis, which is hybrid vigor that results in a greater biomass, increased seed yield, and faster development. The purpose of this study was to estimate yield-related trait heterosis for single cross and three-way cross hybrids of winter oilseed rape (Brassica napus L.). A population of 60 doubled-haploid (DH) lines and two generations of hybrids were evaluated in field trials to assess six yield-related traits: plant height, number of branches per plant, number of siliques per plant, silique length, number of seeds per silique, and thousand seed weight. Heterosis effects for each trait were estimated by a comparison of the particular hybrid with: (1) the trait mean over both parents—mid-parent heterosis and (2) to the value of better parent—best-parent heterosis. Traits with clear positive heterosis and traits with varied heterosis were observed in this study. For the first group, we include plant height, silique length, and the number of seeds per silique—a large number of hybrids expressed significant positive heterosis for these traits, independent from the year of observations and the type of hybrid. For the second group, with varied heterosis, we can include the number of branches and siliques per plant and thousand seed weight. For these traits, hybrids exhibited both positive and negative significant heterosis, without a clear pattern for the years and types of hybrids.


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.


Sign in / Sign up

Export Citation Format

Share Document