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A Developmental Study of the Inflorescence and the Flower of Rapeseed (Brassica napus. cv. Hyola) Using Epi-Illumination Light Microscopy
F. Valipour,M. Khosrowchahli,J. Karapetian,M.R. Dadpour
Journal of Biological Sciences , 2007,
Abstract: Ontogeny and the developmental pattern of flower organs of Brassica napus (cv. Hyola) were investigated using epi-illumination microscopy and image analyzing. Similar results as compared with Scanning Electron Microscopy (SEM) were obtained with this simplified and amenable procedure. Using this microscopy technique we have demonstrated that after the transition of the vegetative apex into the reproductive apex in the 3-leaved seedlings, flower primordia initiation takes place in a helical phyllotactic pattern and the initiation of flower organs pursues the following steps; sepals, stamens, gynoecium and petals. In the formation of four sepals, the abaxial sepal primordium initiated first and it was followed by the formation of the two others in the lateral position. The adaxial sepal primordium was initiated in the last step. Of the six stamens, the four long ones, were initiated first and they were positioned in an alternating order with the four sepals. The two short stamens were initiated in a basipetal manner and in the outside of the long stamens, opposite to the lateral sepals. The remainder part of the apex grows upward to produce an oval, hollow tube which will form the gynoecium. Petal primordia grow slowly and they were initiated after stamens and gynoecium initiation on either side of the two short stamens. The gynoecium at maturity was characterized with a papillated stigma and an elongated style. The ovary was long and divided by a septum in the internal side of the ovary. Sepals, style and the abaxial zone of anthers showed stomatas but they were absent in the petals.
Surveying the occurrence of subspontaneous glyphosate-tolerant genetically engineered Brassica napus L. (Brassicaceae) along Swiss railways
Nicola Schoenenberger, Luigi D’Andrea
Environmental Sciences Europe , 2012, DOI: 10.1186/2190-4715-24-23
Abstract: Seventy-nine railway areas were sampled in Switzerland and the Principality of Liechtenstein, and the feral presence of oilseed rape was detected in 58 of them. A total of 2403 individuals were tested for genetic modification using commercially available immunologic test kits. In four localities, one located in Lugano and three in the area of Basel, a total of 50 plants expressing the CP4 EPSPS protein were detected. In two of the localities, survival of herbicide applications was observed. The populations were probably introduced through contaminated seed spills from freight trains, or during the transfer of goods from cargo ships to trains.Railways represent an ideal system for herbicide resistant transgenic plants to establish and spread as a result of high selective pressure in favour of herbicide resistance with consequent increased difficulties to keep the infrastructure free of weeds. Crop-to-wild gene flow can occur as several sexually compatible species which are congeneric or in allied genera to oilseed rape were found growing sympatrically. Moreover, the capillary presence of railways in the agricultural landscape provides a putative source of contamination of GE-free agriculture. Our results suggests that carefully adapted monitoring designs may be set in order to detect introduction events that can lead to rapid establishment and growing populations as the accepted contamination thresholds are likely to be biologically insufficient to prevent further environmental contamination.Global cultivation of oilseed rape (Brassica napus L.) has been gradually increasing over the last 10?years, reaching about 31.5 Mha in 2010 [1]. In 2011, 26% of the global land area dedicated to oilseed rape was cropped with genetically engineered (GE) cultivars; these cultivars are mainly designed for tolerance to either glyphosate (GLY) or gluphosinate (GLU) [2,3], referred to as genetically engineered herbicide tolerant (GEHT) cultivars. This represents roughly 8 Mha, or 5% o
Effects of Water Deficit Stress on Several Quantitative and Qualitative Characteristics of Canola (Brassica napus L.) Cultivars
Mohammad HOSSEINI,Payman HASSIBI
Notulae Scientia Biologicae , 2011,
Abstract: Water deficit stress considered as one of the most important limiting factors for oil seed canola (Brassica napus L.) growth and productivity in Iran. To evaluate the effects of water deficit stress on some qualitative and quantitative characteristics of canola cultivars, this experiment in a greenhouse trial carried out as factorial based on completely randomized design with three replications in Shahid Chamran University of Ahwaz (Iran). Canola cultivars, including ‘Hyola 308’, ‘Hyola 401’ and ‘RGS 003’ as first factor, and the second one was three levels of water deficit stress, including stress at early stem elongation stage to early flowering (D1), early flowering stage to early emergence of sacs (D2), beginning of stem elongation stage to early emergence of sacs (D3) and normal irrigation (C, as check). Results showed that the interaction between water deficit stress and cultivars affected biological yield, seed oil yields and harvest index (p≤0.01), dry matter and economic yield (p≤0.05). Water deficit stress reduced grain oil yields. ‘Hyola 308’ under stress at beginning stem elongation stage to early flowering had the lowest oil yields (1.1 g plants-1) and ‘Hyola 401’ under non-stress conditions showed highest oil yields (4.3 g plants-1). The decrease of oil yields at the flowering stage to stem elongation stage was more than the other stages. In addition, water deficit stress reduced harvest index in the three stress levels due to reduced economic yield and reduced biological yield. Stress susceptibility index for ‘Hyola 401’ at the beginning of stem elongation stage to early emergence of sacs was 0.914 and the ‘Hyola 308’ showed 1.12 at the beginning of stem elongation stage to early emergence of sacs respectively, which it can implies that ‘Hyola 308’ is more sensitive than ‘Hyola 401’ to water deficit stress.
Effect of Lead on Germination, Growth and Activity of Catalase and Peroxidase Enzyme in Root and Shoot of Two Cultivars of Brassica napus L.  [PDF]
Reza Haji Hosseini,Maliheh Khanlarian,Mahlagha Ghorbanli
Journal of Biological Sciences , 2007,
Abstract: In this project the different concentration of lead [(NO3)2Pb] (0, 100, 200, 400, 600, 800 and 1000 μM) on germination and the effect of nutrient solution with and without lead (0, 100, 200 and 400 μM), in hydroponics culture were examined. The growth parameters and activity of enzymes catalase and peroxidase on Brassica napus cv. Pf 7045 91 and Hyola 401 were studied. Lead caused a decrease on germination in two cultivars (p< 05). By increasing lead concentration more decreasing in germination on Pf than the Hyola has been shown. Growth parameters on both cultivars have been decreased by lead effect. The enzyme activity of catalase and peroxidase in root and shoot on both cultivars by increasing lead concentration has been increased. The activity of root peroxidase has shown significant decrease only in high lead concentration on Pf (p< 0.05). The results show that the germination on Pf was more resistant than the Hyola and at vegetative stage in Hyola has more resistance than the Pf.
Comparative Analysis and EST Mining Reveals High Degree of Conservation among Five Brassicaceae Species  [PDF]
Jyotika Bhati,Humira Sonah,Tripta Jhang,Nagender Kumar Singh,Tilak Raj Sharma
International Journal of Genomics , 2010, DOI: 10.1155/2010/520238
Abstract: Brassicaceae is an important family of the plant kingdom which includes several plants of major economic importance. The Brassica spp. and Arabidopsis share much-conserved colinearity between their genomes which can be exploited for the genomic research in Brassicaceae crops. In this study, 131,286 ESTs of five Brassicaceae species were assembled into unigene contigs and compared with Arabidopsis gene indices. Almost all the unigenes of Brassicaceae species showed high similarities with Arabidopsis genes except those of B. napus, where 90% of unigenes were found similar. A total of 9,699 SSRs were identified in the unigenes. PCR primers were designed based on this information and amplified across species for validation. Functional annotation of unigenes showed that the majority of the genes are present in metabolism and energy functional classes. It is expected that comparative genome analysis between Arabidopsis and related crop species will expedite research in the more complex Brassica genomes. This would be helpful for genomics as well as evolutionary studies, and DNA markers developed can be used for mapping, tagging, and cloning of important genes in Brassicaceae. 1. Introduction Brassicaceae species consisting of various agronomically important crops like oilseeds, broccoli, cabbage, black mustard, and other leafy vegetables are cultivated in most parts of the world. The genus Brassica is evolutionarily closely related to model crucifer plant Arabidopsis thaliana, since both are members of the family Brassicaceae and reported to have diverged 14–20 million years ago [1]. The major centers of diversity of Brassicaceae family are southwestern and central Asia and the Mediterranean region whereas the arctic, western North America, and the mountains of South America are secondary centers of diversity [2]. The genus Brassica is a monophyletic group within the Brassicaceae. It includes the cultivated oil seeded species, Brassica juncea, B. napus, and B. rapa and vegetable B. oleracea, which are also very closely related to A. thaliana. The genomes of the three diploid Brassica species, that is, B. rapa, B. nigra, and B. oleracea, have been designated as A, B, and C, respectively, where as the genomes of the amphidiploids, B. juncea and B. napus, have been designated as AB and AC, respectively [3–5]. Comparative genomics is a powerful tool for genome analysis and annotation. There are two basic objectives for comparative genomics. First, to understand the detailed process of evolution at the gross level (the origin of the major classes of organism) and
Comparative Analysis and EST Mining Reveals High Degree of Conservation among Five Brassicaceae Species  [PDF]
Jyotika Bhati,Humira Sonah,Tripta Jhang,Nagender Kumar Singh,Tilak Raj Sharma
Comparative and Functional Genomics , 2010, DOI: 10.1155/2010/520238
Abstract: Brassicaceae is an important family of the plant kingdom which includes several plants of major economic importance. The Brassica spp. and Arabidopsis share much-conserved colinearity between their genomes which can be exploited for the genomic research in Brassicaceae crops. In this study, 131,286 ESTs of five Brassicaceae species were assembled into unigene contigs and compared with Arabidopsis gene indices. Almost all the unigenes of Brassicaceae species showed high similarities with Arabidopsis genes except those of B. napus, where 90% of unigenes were found similar. A total of 9,699 SSRs were identified in the unigenes. PCR primers were designed based on this information and amplified across species for validation. Functional annotation of unigenes showed that the majority of the genes are present in metabolism and energy functional classes. It is expected that comparative genome analysis between Arabidopsis and related crop species will expedite research in the more complex Brassica genomes. This would be helpful for genomics as well as evolutionary studies, and DNA markers developed can be used for mapping, tagging, and cloning of important genes in Brassicaceae.
Promoter Variation and Transcript Divergence in Brassicaceae Lineages of FLOWERING LOCUS T  [PDF]
Jing Wang, Clare J. Hopkins, Jinna Hou, Xiaoxiao Zou, Chongnan Wang, Yan Long, Smita Kurup, Graham J. King, Jinling Meng
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0047127
Abstract: Brassica napus (AACC, 2n = 38), an oil crop of world-wide importance, originated from interspecific hybridization of B. rapa (AA, 2n = 20) and B. oleracea (CC, 2n = 18), and has six FLOWERING LOCUS T (FT) paralogues. Two located on the homeologous chromosomes A2 and C2 arose from a lineage distinct from four located on A7 and C6. A set of three conserved blocks A, B and C, which were found to be essential for FT activation by CONSTANS (CO) in Arabidopsis, was identified within the FT upstream region in B. napus and its progenitor diploids. However, on chromosome C2, insertion of a DNA transposable element (TE) and a retro-element in FT upstream blocks A and B contributed to significant structural divergence between the A and C genome orthologues. Phylogenetic analysis of upstream block A indicated the conserved evolutionary relationships of distinct FT genes within Brassicaceae. We conclude that the ancient At-α whole genome duplication contributed to distinct ancestral lineages for this key adaptive gene, which co-exist within the same genus. FT-A2 was found to be transcribed in all leaf samples from different developmental stages in both B. rapa and B. napus, whereas FT-C2 was not transcribed in either B. napus or B. oleracea. Silencing of FT-C2 appeared to result from TE insertion and consequent high levels of cytosine methylation in TE sequences within upstream block A. Interestingly, FT-A7/C6 paralogues were specifically silenced in winter type B. napus but abundantly expressed in spring type cultivars under vernalization-free conditions. Motif prediction indicated the presence of two CO protein binding sites within all Brassica block A and additional sites for FT activation in block C. We propose that the ancestral whole genome duplications have contributed to more complex mechanisms of floral regulation and niche adaptation in Brassica compared to Arabidopsis.
Conservation of Pollinator Resources in Botanic Gardens  [PDF]
A. Bhattacharya
Our Nature , 2010, DOI: 10.3126/on.v8i1.4341
Abstract: This review presents the recent problems and future prospects of plant and pollinator resources in botanic gardens in the context of the role of botanic gardens for biodiversity conservation. Various anthropogenic disturbances, habitat and forage crisis, sound and light pollution, pesticide misuse, ignorance of plant-pollinator interactions in the botanic gardens are the primary concerns responsible for decline of plant and pollinator resources in botanic gardens. Several alternative procedures are to be followed have been discussed to overcome the problems for effective biodiversity conservation in botanic gardens. DOI: 10.3126/on.v8i1.4341
A spatial assessment of Brassica napus gene flow potential to wild and weedy relatives in the Fynbos Biome
M. A. McGeoch,J. M. Kalwij,J. I. Rhodes
South African Journal of Science , 2010, DOI: 10.4102/sajs.v105i3/4.57
Abstract: Gene flow between related plant species, and between transgenic and non-transgenic crop varieties, may be considered a form of biological invasion. Brassica napus (oilseed rape or canola) and its relatives are well known for intra- and inter-specific gene flow, hybridisation and weediness. Gene flow associated with B. napus poses a potential ecological risk in the Fynbos Biome of South Africa, because of the existence of both naturalised (alien, weedy) and native relatives in this region. This risk is particularly pertinent given the proposed use of B. napus for biofuel and the potential future introduction of herbicide-tolerant transgenic B. napus. Here we quantify the presence and co-occurrence of B. napus and its wild and weedy relatives in the Fynbos Biome, as a first step in the ecological risk assessment for this crop. Several alien and at least one native relative of B. napus were found to be prevalent in the region, and to be spatially congruent with B. napus fields. The first requirement for potential gene flow to occur has thus been met. In addition, a number of these species have elsewhere been found to be reproductively compatible with B. napus. Further assessment of the potential ecological risks associated with B. napus in South Africa is constrained by uncertainties in the phylogeny of the Brassicaceae, difficulties with morphology-based identification, and poor knowledge of the biology of several of the species involved, particularly under South African conditions.
Effects of Nitrogen and Sulphur Fertilizers on Yield, Yield Components and Oil Content of Oilseed Rape (Brassica napus L.)  [PDF]
H. Farahbakhsh,N. Pakgohar,A. Karimi
Asian Journal of Plant Sciences , 2006,
Abstract: Present experiment was carried out to investigate the influence of nitrogen (150 and 300 kg ha-1) and sulphur (0, 100 and 200 kg ha-1) fertilizers on yield, yield components and oil content of two cultivars of oilseed rape (Brassica napus L.), Hyola 308 and PF7045. The experiment was factorial, laid out in Randomized Block Design with three replicates. Biological and economical yield were significantly different between cultivars. The higher grain weight of Hyola 308 was due to bigger size of pods and heavier seed weight. Application of nitrogen did affect biological yield positively but it did not affect grain weight. The increase in dry matter production or biological yield was 14% when the amount of nitrogen fertilizer increased from 150 to 300 kg ha-1. Sulphur application affected neither dry matter production nor grain weight. Two cultivars were significantly different for oil contents. Nitrogen affected the oil content negatively and decreased it by 3.3%. Increasing the amount of sulphur fertilizer from zero to 200 kg ha-1 resulted in an increase in oil content.
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