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1.
Jo Oldknow Tanya M. Franklin Martin Trick Sharon Allard Laurian S. Robert 《Sexual plant reproduction》1995,8(4):254-255
The DNA sequence data reported have been lodged in the Genbank, EMBL and DDBJ databases under the accession numbers Z21609 and Z26914 相似文献
2.
Experiments on three autumn-heading cauliflower genotypes (2 hybrids and a genotype selected from a population) were conducted to study different factors affecting anther culture. Culture conditions of the donor plants proved to be important: the best results were obtained during spring in a greenhouse where the temperature was maintained between 10 and 20°C. Overall winter and spring seemed more suitable than summer and early autumn for culture establishment. The optimal bud development stage depended on the genotype: for the hybrid 702, the greatest number of embryos for 100 plated anthers was obtained at the uninucleate pollen stage of the microspores; for V23.2 and 703, the optimal stage of the buds corresponded to the first mitotic division. Sucrose proved to be the best carbon supply for embryogenesis with an optimal concentration of 140 g l-1. The addition of a cytokinin (BAP) in the medium led to lower embryo production, and this negative effect increased when the hormone concentration in the medium increased. The use of liquid medium and a dark incubation period immediately after the high temperature treatment were favourable for embryogenesis. 相似文献
3.
4.
Thirty-day-old plants of mustard (Brassica juncea L.) were sprayed with 10−10, 10−8, or 10−6 M aqueous solution of 28-homobrassinolide (HBR). The HBR-treated plants were healthier than those treated with water and
yielded more. Maximum increase over control was found in 60-d-old, 10−8 M-HBR-treated plants in fresh and dry mass per plant, carbonic anhydrase (CA, E.C. 4.2.1.1) activity, and net photosynthetic
rate (P
N), at harvest in number of pods per plant and seed yield per plant (the respective values were 25, 30, 34, 69, 24, and 29
%). A further increase in the concentration of HBR (10−6 M) did not make any additional impact on the growth and yield. Increased CA activity and P
N were correlated with growth and seed yield.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
Xue‐Feng Zhou Peng Zhang Hui‐Fang Pi Yong‐Hui Zhang Han‐Li Ruan Hui Wang Ji‐Zhou Wu 《化学与生物多样性》2009,6(8):1202-1207
Two new triterpenoids, 1 and 2 , were isolated from the hepatoprotective AcOEt fraction of the roots of Actinidia chinensis, together with eight known 12‐en‐28‐oic acids of oleanane or ursane type, 3 – 10 . The two new compounds were elucidated as 2α,3β‐dihydroxyurs‐12‐en‐28,30‐olide ( 1 ) and 2α,3β,24‐trihydroxyurs‐12‐en‐28,30‐olide ( 2 ), on the basis of spectroscopic (IR, NMR, and MS) analyses. The chemotaxonomic significances of some triterpenoids were also discussed. 相似文献
6.
Steven Szarka Melanie Fitch Santiago Schaerer Maurice Moloney 《Plant molecular biology》1995,27(2):263-275
In order to investigate the role of cell division in plant development, we isolated several plant genes which encode homologues of animal and yeast cell cycle regulators known as cyclins.Through the use of degenerate primers and the polymerase chain reaction (PCR) we isolated a Brassica sequence which showed homology to the cyclin box functional domain found within cyclin proteins. Southern blot analysis indicated that Brassica napus has a large number of genes containing cyclin box-related sequences. This was further supported by the isolation of cyclin box sequences from six different genomic clones. In addition, we have isolated two different cyclin cDNA clones, BnCYC1 and BnCYC2, from a Brassica napus shoot apical cDNA library. Both of the cDNA clones contain a destruction box regulatory domain similar to animal mitotic cyclins.Northern blot analysis using BnCYC2 shows mRNA levels which correlate well with the level of cell division in various tissues. Messenger RNA abundance was highest in 1–3 mm leaves, root tips and shoot apices. The mRNA detected using BnCYC1 was restricted to young leaves and the shoot apex, suggesting divergent, organ-specific roles for cyclin family members. The results demonstrate that the plant cyclin gene family is more extensive than previously demonstrated and consists of genes expressed in all dividing tissues as well as a subset of developmentally specific members. 相似文献
7.
Precise editing of CLAVATA genes in Brassica napus L. regulates multilocular silique development 下载免费PDF全文
Yang Yang Kaiyu Zhu Huailin Li Shaoqing Han Qingwei Meng Shahid Ullah Khan Chuchuan Fan Kabin Xie Yongming Zhou 《Plant biotechnology journal》2018,16(7):1322-1335
Multilocular silique is a desirable agricultural trait with great potential for the development of high‐yield varieties of Brassica. To date, no spontaneous or induced multilocular mutants have been reported in Brassica napus, which likely reflects its allotetraploid nature and the extremely low probability of the simultaneous random mutagenesis of multiple gene copies with functional redundancy. Here, we present evidence for the efficient knockout of rapeseed homologues of CLAVATA3 (CLV3) for a secreted peptide and its related receptors CLV1 and CLV2 in the CLV signalling pathway using the CRISPR/Cas9 system and achieved stable transmission of the mutations across three generations. Each BnCLV gene has two copies located in two subgenomes. The multilocular phenotype can be recovered only in knockout mutations of both copies of each BnCLV gene, illustrating that the simultaneous alteration of multiple gene copies by CRISPR/Cas9 mutagenesis has great potential in generating agronomically important mutations in rapeseed. The mutagenesis efficiency varied widely from 0% to 48.65% in T0 with different single‐guide RNAs (sgRNAs), indicating that the appropriate selection of the sgRNA is important for effectively generating indels in rapeseed. The double mutation of BnCLV3 produced more leaves and multilocular siliques with a significantly higher number of seeds per silique and a higher seed weight than the wild‐type and single mutant plants, potentially contributing to increased seed production. We also assessed the efficiency of the horizontal transfer of Cas9/gRNA cassettes by pollination. Our findings reveal the potential for plant breeding strategies to improve yield traits in currently cultivated rapeseed varieties. 相似文献
8.
Potential biases in screening for plant resistance to insect pests: an illustration with oilseed rape 总被引:1,自引:0,他引:1 下载免费PDF全文
M. R. Hervé M. Leclair L. Frat C. Paty D. Renaud A. M. Cortesero 《Journal of Applied Entomology》2017,141(1-2):150-155
Breeding to increase crop resistance is a common strategy to decrease damage caused by insect pests, especially in the current context where insecticides are becoming at the same time less accepted by society and less efficient because of widespread pest resistance. The main bottleneck of this strategy is phenotyping. Although simple, high‐throughput methods have been proposed which could be highly useful, they may raise conceptual issues. Using field and laboratory experiments on oilseed rape (Brassica napus) and the pollen beetle (Brassicogethes aeneus syn. Meligethes aeneus), we illustrated possible difficulties with this approach: (i) field screenings might not represent the real attractiveness of the tested genotypes; (ii) plant phenology or spatial organization of the genotypes might bias field screening results; (iii) experiments based on detached plant parts (here, single flower buds or anthers) might not allow to infer the plant–insect relationship of the whole plant. We propose ways to better take these risks into account. 相似文献
9.
Under stress integrated germination test (SIGT), seeds undergo osmo-saline stresses, which enable to detect differences in vigour of long-term stored seeds with high germination percentage (G%). The quality of Brassica villosa subsp. drepanensis seeds stored in a genebank (at ? 20°C for 16 years) was compared with seeds at harvest by standard germination tests (GT), SIGT and cytogenetic analysis. No differences were detected in G% and mean germination time under GT. Conversely, SIGT performed with NaCl ? 0.9 MPa osmotic potential did not influence G% at harvest but reduced that of stored seeds, SIGT at ? 1.4 MPa reduced G% of both. Cytogenetic analysis showed reduction of mitotic index, appearance of chromosomal aberrations and smaller nucleoli in stored seeds compared with harvest seeds germinated in water. SIGT at ? 0.9 MPa had no effect on mitotic index, but increased chromosome aberrations and nucleoli number. SIGT at ? 1.4 MPa inhibited G% of harvest and stored seeds, reduced mitoses in harvest and completely prevented it in stored seeds. The results indicate that GT does not faithfully reflect the quality of stored seeds, with misinterpretation of their vigour, whereas SIGT and cytogenetical parameters are sensitive, reliable and inexpensive methods for early prediction of genetic erosion in germplasm banks. 相似文献
10.