SummaryRapeseed plants have been regenerated after fusion between protoplasts bearing cytoplasms of different genera. Cybrids combine, in a first experiment Brassica napus chloroplasts and a cytoplasmic male sterility (cms) trait coming from Raphanus sativus, in a second experiment chloroplasts of a triazine resistant Brassica campestris and cms trait from Raphanus sativus. Transfer of chloroplasts has been confirmed by restriction cp DNA analysis and two dimensional thylakoïd protein electrophoresis. These plants may be very useful for Brassica hybrid seed production.

Intergeneric cytoplasmic hybridization in cruciferae by protoplast fusion

Considerable progress has been accomplished in the cellular and molecular biology of Brassica species in the past few years. Plant regeneration has been increasingly optimized via organogenesis and somatic embryogenesis using various explants; with tissue culture improvements focusing on factors such as age of the explant, genotype, and media additives. The production of haploids and doubled haploids using microspores has accelerated the production of homozygous lines in the Brassica species. Somatic cell fusion has facilitated the development of interspecific and intergeneric hybrids in the sexually incompatible species of Brassica. Crop improvement using somaclonal variation has also been achieved. The use of molecular markers in marker-assisted selection and breeding, transformation technology for the introduction of desirable traits, and a comparative analysis of these as well as their future prospects are important parts of the current research that is reviewed.

Invited review: brassica biotechnology: progress in cellular and molecular biology

Medicinal plants are sources of important therapeutic aid for alleviating human ailments. With increasing realization of the health hazards and toxicity associated with the indiscriminate use of synthetic drugs and antibiotics, interest in the use of plants and plant-based drugs has revived throughout the world. However, a large number of medicinal plants remain to be investigated for their possible pharmacological value. Most of the pharmaceutical in- dustry is highly dependent on wild populations for the supply of raw materials for extraction of medicinally impor- tant compounds. Due to a lack of proper cultivation practices, destruction of plant habitats, and the illegal and indiscriminate collection of plants from these habitats, many medicinal plants are severely threatened. Advanced biotechnological methods of culturing plant cells and tissues should provide new means of conserving and rapidly propagating valuable, rare, and endangered medicinal plants. This paper describes the work carried out at the Taiwan Agricultural Research Institute and Chaoyang University of Technology on in vitro propagation of some important medicinal plants.

/pdf/studies-on-tissue-culture-of-chinese-medicinal-plant-36ecmhp3uz.pdf

Studies on tissue culture of Chinese medicinal plant resources in Taiwan and their sustainable utilization

This chapter reviews the agricultural role of the Brassicaceae (Cruciferae) or mustard family. The family includes many economically important edible and industrial oilseed, vegetable, condiment, and fodder crop, such as. It also includes the molecular plant model, such as Arabidopsis thaliana. Current crops are reviewed and new and underutilized crucifer crop species discussed. Proposed new uses for these crops, such as biofuel platforms or green manure covers or biofumigants, are also briefly reviewed. The family also contains a rich source of agronomic and economic traits in its highly diverse wild germplasm. Traits discussed in this chapter include morphological and chemical traits; physiological traits such as C3–C4 photosynthesis, cytoplasmic male sterility, apomixis, and regeneration or transformation ability; and tolerances to various stresses such as salt, heavy metals, cold, drought, herbicides, diseases, insect, and nematode pests. These traits are of potential value in crop improvement programs and many wild crucifers now serve as model species in their study.

https://www.springer.com/cda/content/document/cda_downloaddocument/9781441971173-c1.pdf?SGWID=0-0-45-1033755-p174023801

Brassicaceae in Agriculture

Somatic hybrids between Brassica napus (oilseed rape) and its wild relative Sinapis arvensis (Xinjiang wild mustard) from northwestern China were produced by fusing mesophyll protoplasts. Fifty-four plants were identified as symmetric hybrids and four as asymmetric hybrids by random amplified polymorphic DNA analysis and nuclear DNA content. The morphology of investigated 58 hybrid plants resembled characters from both parental species. Highly fertile hybrids were recovered where the fertility was associated with the choice of B. napus genotype. Enhanced disease resistance to Leptosphaeria maculans was found in S. arvensis and in the hybrid offspring. This plant material has great potentials not only for use as a bridge for the introduction of a number of valuable traits from the wild species to Brassica crops but also for breeding new varieties with improved blackleg resistance.

Production of fertile intergeneric somatic hybrids between Brassica napus and Sinapis arvensis for the enrichment of the rapeseed gene pool

Protoplasts from a total of thirty-six genotypes of Brassica species – B. napus, B. campestris (syn. B. rapa), B. juncea, and three distant relatives, Orychophragmus violaceus, Isatis indigotica and Xinjiang wild rape – were analysed for shoot regeneration using a feeder culture system. With the exception of B. campestris and Xinjiang wild rape, some genotypes of all the species could regenerate plants with high efficiency (above 20% of isolated calli initiating shoots). Several genotypes with high regeneration ability were elite breeding lines. Culture conditions as well as genotype had a significant impact on shoot regeneration frequency. In particular, silver nitrate added to the regeneration medium at doses of 6 and 30 μM improved shoot regeneration frequency to 25.4% and 52.2% of isolated calli, respectively, compared to 7.3% percent shoot regeneration without silver nitrate in seven responsive genotypes. Addition of silver nitrate to the regeneration medium also induced shoot regeneration in non-responsive genotypes. Intact plants could be obtained within three months from protoplast isolation in the regenerative genotypes using the current culture system. Advantages of mesophyll protoplasts as compared to protoplasts isolated from hypocotyls for genetic manipulation in Brassica species are discussed.

Plant regeneration capacity of mesophyll protoplasts from Brassica napus and related species

In Brassica oleracea L, plant regeneration from protoplasts is genotype-dependent and colony formation can be obtained routinely In order to identify genes for regenerability, we performed a genetic analysis of the characteristic in the F2 generation of a cross between two accessions selected for high and low regenerability Regeneration frequencies were obtained from protoplast culture of 248 individual F2 plants after 5, 10, and 15 weeks of culture on regeneration medium Broad-sense heritability estimate was 0492 at the early stage and lower (0046–0149) at advanced stages The frequency distribution observed during short-term culture can be explained by two independent loci with duplicate dominant genes controlling regeneration In long-term culture, one additional dominant gene can confer regeneration; ie, three independent loci are responsible for regenerability The results suggest that selection for high regeneration response may be efficient at early stages because of the lower environmental influence on the characteristic, and because fewer genes are involved at this stage than at advanced stages The control of regenerability by a few dominant genes facilitates incorporation of the trait into breeding material Molecular markers linked to the genes may assist in the selection of genotypes with high regeneration percentage in the future

Genetic analysis of protoplast regeneration ability in Brassica oleracea

Protoplasts of an accession of Isatis indigotica Fort. were isolated from mesophyll tissue by enzymatic digestion and cultured using a feeder cell system. Shoot regeneration efficiency was 100% via organogenesis among 627 isolated calluses within 30–37 days. Among these shoot initiating calluses, 162 (22.6%) developed normal shoots with multiple (2–5) shoots per callus. The remaining calluses developed only vitreous shoots. High concentration (5 μM) of indole-3-butyric acid had a positive effect on rooting compared to low concentration (0.5 μM) of indole-3-butyric acid and α-naphthalene-acetic acid. The average rooting efficiency of regenerated shoots of two experiments was higher on LS medium with 5 μM indole-3-butyric acid than on LS medium without growth regulators. Twenty-nine plantlets, with 2–3 expanded leaves and roots were potted in soil and 22 developed normally to maturity in the glasshouse.

Lise N. Hansen

Papers

Plant regeneration capacity of mesophyll protoplasts from Brassica napus and related species

Genetic analysis of protoplast regeneration ability in Brassica oleracea

Plant regeneration from mesophyll protoplasts in Isatis indigotica