Twenty one F2 progenies derived from a 7×7 diallel crosses along with parents were evaluated for grain yield, flowering and maturity time Due to significant genotypic effects for all traits, genetic analyses were performed on F2 progenies including analyses of combining ability and genetic components The Analysis of variance revealed that both additive and non-additive genetic effects were involved in controlling these traits GCA/SCA ratios were 091 for days to flowering, 095 for days to maturity and 083 for grain yield which indicated that the additive gene effects were more important than non-additive gene effects for all these traits Narrow-sense heritability was high for days to flowering (7312%) and days to maturity (8199%) and low for grain yield (3015%) Heterosis in hybrids seemed to be largely determined by complementary epistasis as well as genetic distance between the parents The spring-type varieties Tower and Regent appeared as the best parents for earliness whereas winter-type varieties DR and Ceres were best parents for high grain yield It could be concluded from the study that S1 recurrent selection would be effective to improve the performance of these genotypes for grain yield, flowering and maturity time The selected S1 lines from each cycle can be used in a pedigree-breeding program to identify superior genotypes

https://ijpp.gau.ac.ir/article_638_7f02c369f4f8e90e3707c8ad6883d9f1.pdf

Genetic analysis of grain yield, days to flowering and maturity in oilseed rape (Brassica napus L.) using diallel crosses

Canola is a major oil crop in the Yangtze River Basin of China, and its yield and oil content vary significantly from year to year due to changes in sowing time and inter-annual climate variability. However, there have been no studies to quantify the impacts of sowing time and climate variability. Experimental data to analyse the response of canola growth to sowing date are limited to a few seasons; however, combining these data with modelling provides an efficient means to study the impact of sowing date and historical climate variation. The APSIM-Canola model was calibrated and tested using data from three field experimental sites in the Yangtze River Basin. These experiments included different cultivars and sowing dates, and recorded major phenological stages, biomass, and grain yield. After calibration of the phenological parameters and maximum harvest index, the model was able to simulate the onset of phenological stages with different sowing dates, and to explain 75% of the variation in biomass and yield caused by late sowings. However, the model overestimated canola yield under late sowing dates. The results revealed that canola yield declined linearly with late sowing time, mainly due to shortened vegetative growth stages, and varied significantly due to inter-annual climate variability. The yield potential at the study region is ~3 t/ha, on average. However, this potential cannot be achieved in the rice–canola double-cropping system due to later sowing time after rice harvest in mid–later October. Transplanting canola may still be an effective measure against the constraint of season length to achieving higher yields of both rice and canola.

https://bioone.org/journals/crop-and-pasture-science/volume-63/issue-5/CP11332/Phenological-development-and-grain-yield-of-canola-as-affected-by/10.1071/CP11332.pdf

Phenological development and grain yield of canola as affected by sowing date and climate variation in the Yangtze River Basin of China

Nitrogen storage and remobilization in Brassica napus L. during the growth cycle: nitrogen fluxes within the plant, changes in soluble proteins patterns and influence of reproductive sink tissue removal

In order to evaluate spring rapeseed (Brassica napus L.) cultivars subjected to drought stress, the ex periments were laid out as a randomized complete block design with split-plot arrangement (4 replications), during 2008–2009 and 2009–2010 cropping seasons at Seed and Plant Improvement Institute of Karaj, Iran. In this research the main factors, allotted to the main plots, consisted of two irrigation regimes including normal irrigation (I) during the total growing period based on 80 mm evaporation from class A pan and water deficit stress (S) as ceased irrigation since the flowering stage until full maturity. Subplots, which consisted of split plots, were devoted to twenty spring rapeseed cultivars. Water deficit stress, caused reduction in plant height, branch plant-1, siliqua plant-1, seed siliqua-1, 1000-seed weight, seed yield, biological yield, oil content, and oil yield while it did not affect harvest index significantly. Correlation coefficient analysis revealed that number of siliquae per plant had the highest correlation with seed yield (r = 0.65, P < 0.01) as compared with other yield components. Among cultivars, ‘Hyola 401’ (hybrid) produced the highest seed yield (4588 kg ha-1) under normal irrigation, and RGS003 had the maximum seed yield (3577 kg ha-1) and stress tolerance index (STI = 0.952) under water deficit stress conditions. ‘Quantum’ with the least seed yield in both irrigation patterns (I – 3492 kg ha-1 and S – 2948 kg ha-1) and low STI (0.601) had the highest susceptibility to water deficit stress. Based on the result of this study, it can be concluded that RGS003 cultivar had better capability to tolerate drought stress and could produce greater seed yield under stress conditions.

The effect of drought stress on qualitative and quantitative traits of spring rapeseed (Brassica napus L.) cultivars.

Optimisation of water and nitrogen use is an effective management tool to conserve resources and reduce environmental pollutions. Response surface methodology (RSM) is defined as a collection of mathematical and statistical methods that are used to develop, to improve or to optimize a product or process. In order to determine optimum levels of water, nitrogen and planting density of canola (Brassica napus L.), a 2-year experiment (2010–2011) was carried out by central composite design as RSM at the research station of Ferdowsi University of Mashhad. The treatments were designed based on low and high levels of irrigation (1500 and 4000 m3 ha−1), nitrogen (0 and 400 kg N ha−1) and density (50 and 150 plant m−2) as independent variables. Furthermore, seed yield, nitrogen losses, nitrogen use efficiency (NUE) and water use efficiency (WUE) were measured as response variables in a full quadratic polynomial model. Optimum levels of irrigation, nitrogen and planting density were suggested to achieve the ...

Optimizing water, nitrogen and crop density in canola cultivation using response surface methodology and central composite design

Comparing winter rapeseed cultivars (brassica napus l.) according to yield and yield components in cold regions of iran

Effect of water deficit and different nitrogen rates on yield, yield components and physiological traits of two rapeseed (brassica napus l.) cultivars

Effect of drought stress on yield and yield components of autumn rapeseed varieties

Daneshmand, A. R., A. H. Shirani-Rad, Gh. Nour-Mohammadi, Gh. Zarei and J. Daneshian. 2008. Effect of irrigation regiems and nitrogen levels on seed yield and seed quality of two rapeseed (Brassica napus L.) cultivars. Iraniam Journal of Crop Sciences. 10(3): 244-261 (in Persian). In order to determine the effects of water deficit and different nitrogen levels on seed quality, seed oil yield and seed yield in rapeseed, two field experiments were conducted using a factorial split-plot in randomized complete block design in, 2005-2006 and 2006-2007 growing seasons in Seed and Plant Improvement Institute, Kafaj, Iran. In this study, three water regimes (irrigation after 40, 60 and 80 percent depletion of soil water) and four nitrogen levels (0, 75, 150 and 225 Kg/ha) as factorial in main plots and two cultivars (Zarfam and Modena) as sub-plots, were studied. Results showed that increasing the nitrogen rate from 0 to 220 kg/ha and ??? in soil water, increased the seed yield. Increase in seed yield was related to increasing the number of siliques in plant and number of seeds per silique in both conditions. In water stress condition the seed oil decreased, but the seed protein increased. Increasing nitrogen use decreased seed oil, but increased seed protein. Results also showed that in both conditions (normal irrigation and water stress), high levels of N application could produce higher seed yield and seed oil yield. Zarfam had a higher nitrogen uptake and mobilization under normal irrigation and severe water stress conditions, and also in higher and lower nitrogen conditions, hence, produced higher seed

Shiranirad Amir Hossein

Papers

Comparing winter rapeseed cultivars (brassica napus l.) according to yield and yield components in cold regions of iran

Effect of water deficit and different nitrogen rates on yield, yield components and physiological traits of two rapeseed (brassica napus l.) cultivars

Effect of drought stress on yield and yield components of autumn rapeseed varieties

Effect of irrigation regiems and nitrogen levels on seed yield and seed quality of two rapeseed (brassica napus l.) cultivars

Effect of drought stress on grain yield and chlorophyll in rapessed cultivars