Combined field efficacy of <Emphasis Type="Italic">Paranosema locustae</Emphasis> and <Emphasis Type="Italic">Metarhizium anisopliae</Emphasis> var. <Emphasis Type="Italic">acridum</Emphasis> for the control of sahelian grasshoppers

Field trials were conducted to evaluate the efficacy of wheat bran bait formulations of Paranosema locustae and Metarhizium anisopliae for controlling grasshoppers in southeast Niger. Treatments consisted of wheat bran baits mixed with M. anisopliae, P. locustae + M. anisopliae or with P. locustae spores and P. locustae + sugar. Oedaleus senegalensis, Pyrgomorpha cognata and Acrotylus blondeli were the predominant species at the time of application representing ca. 94% of the total population. Bran application was done when O. senegalensis (ca. 75% of the population) was at its early developmental stages, with first, second and third instars accounting for 64–85%. Grasshopper population reduction, P. locustae prevalence and level of infections in the predominant species were monitored. Manual application of P. locustae and M. anisopliae formulated in wheat bran has proven to induce consistent pathogen infection in grasshopper populations. Population density over the three weeks monitoring, typically decreased by 44.7 ± 6.9%, 52.8 ± 8.4%, 73.7 ± 5.5% and 89.1 ± 1.8% in P. locustae, P. locustae + sugar, M. anisopliae and P. locustae + M. anisopliae treated plots respectively. Paranosema locustae prevalence in surviving adult grasshoppers at 28 after application was 48.1 ± 2.3%, 28.9 ± 4.8% and 27.4 ± 3.7%, with infection level of 6.2 ± 0.8 × 10⁶, 2.3 ± 0.3 × 10⁴ and 2.1 ± 0.3 × 10³ spores mg⁻¹ host weight in O. senegalensis, A blondeli and P. cognate respectively. Other species that each accounted for <2% of the community, namely Aiolopus thalassinus, A. simulatrix, Acorypha glaucopsis, Acrotylus patruelis, Anacridium melanorhodon, Diabolocatantops axillaris, Kraussaria angulifera and Schistocerca gregaria were found to show sign of infection. The results from this study suggest that wheat bran application of M. anisopliae and P. locustae alone or in combination, targeting early instars grasshopper could be a valuable option in grasshopper control programs.     

<Emphasis Type="Italic">Fopius arisanus</Emphasis> oviposition in four <Emphasis Type="Italic">Anastrepha</Emphasis> fruit fly species of economic importance in Mexico

We studied the oviposition performance of Fopius arisanus (Sonan) (Hymenoptera: Braconidae) attacking eggs of four fruit flies of the genus Anastrepha Schiner (Diptera: Tephritidae) under laboratory conditions. The complete process of oviposition on an individual egg of Anastrepha ludens (Loew) lasts in average 85.4 ± 2.9 s, including a tremor (25.8 ± 1.03 s) observed in the middle of this process related to the egg’s descent. The average parasitism of A. ludens egg was 60.9 ± 7.5%, with only 1.2% of superparasitized eggs. During individual acts of oviposition, we noted that F. arisanus possesses a highly flexible ovipositor that curves easily as it searches for additional suitable eggs, which may be of particular benefit when a female finds large clutches of eggs. The individual oviposition of F. arisanus in host fruits attacked by Anastrepha spp. varies with the egg clutch size of each fruit fly species: A. serpentina laid the biggest egg clutches (21.3 ± 1.4), followed by A. ludens (14.2 ± 0.9), and A. striata (1.0 ± 0.0) (=A. obliqua). The time spent by F. arisanus in individual ovipositions was parallel to these findings, reinforcing the idea that F. arisanus attacks several eggs in each individual insertion of its ovipositor. Neither formal oviposition acts, nor adult emergences of F. arisanus were registered in A. obliqua. We discuss the potential of F. arisanus as natural enemy of fruit flies of the genus Anastrepha, and explore the eventual developing of its mass rearing. Handling Editor: Torsten Meiners.     

Differential responses of lipid peroxidation and antioxidants in <Emphasis Type="Italic">Alternanthera philoxeroides</Emphasis> and <Emphasis Type="Italic">Oryza sativa</Emphasis> subjected to drought stress

To evaluate oxidative stress and the plant antioxidant system of Alternanthera philoxeroides [Mart.] Griseb and Oryza sativa L. in the response to drought, root and leaf tissues of drought-treated A. philoxeroides and O. sativa were collected and relative water content, stomatal conductance, the concentrations of malondialdehyde, proline and the activities of superoxide dismutase, peroxidases, catalase and total antioxidative activity investigated. The results showed that drought treatment had almost no effect on relative water content in A. philoxeroides but reduced relative water content in O. sativa. A. philoxeroides maintained a greater stomatal conductance than O. sativa under drought stress. In A. philoxeroides levels of lipid peroxidation were lower than in O. sativa and did not change during the experiment. After exposure to drought, concentrations of proline and activities of superoxide dismutase, peroxidases and catalase in A. philoxeroides were between 10% and 30% higher than in O. sativa, whereas total antioxidative activity in A. philoxeroides was several-fold higher than in O. sativa.     

Growth and carrageenan quality of <Emphasis Type="Italic">Kappaphycus striatum</Emphasis> var. <Emphasis Type="Italic">sacol</Emphasis> grown at different stocking densities,duration of culture and depth

Kappaphycus striatum var. sacol was grown in two separate studies: (1) at two stocking densities, and (2) at four different depths, each for three different durations of culture (30, 45 and 60 days) in order to determine the growth rate of the seaweed and evaluate the carrageenan content and its molecular weight. The results demonstrated that stocking density, duration of culture and depth significantly (P < 0.01) affected the growth rate, carrageenan content and molecular weight of K. striatum var. sacol. Decreasing growth rate was observed at both stocking densities and at four depths as duration of culture increased. A lower stocking density (500 g m⁻¹line⁻¹) showed a higher growth rate for the shortest durations, i.e. 30 days, as compared to those grown at a higher density. Likewise, decreasing growth rate was observed as depth increased, except at 50 cm after 60 days of culture. A 45-day culture period produced the highest molecular weight at both stocking densities (500 g m⁻¹line⁻¹ = 1,079.5 ± 31.8 kDa, 1,000 g m⁻¹line⁻¹ = 1,167 ± 270.6 kDa). ‘Sacol’ grown for 30 days at 50 cm (1,178 kDa) to 100 cm (1,200 kDa) depth showed the highest values of molecular weight of carrageenan extracted. The results suggested that K. striatum var. sacol is best grown at a stocking density of 500 g m⁻¹line⁻¹, at a depth of 50–100 cm, and for a duration of 30 days in order to provide the highest growth rate, carrageenan content and molecular weight.     

Effect of fungal infection on reproductive potential and survival time of <Emphasis Type="Italic">Tetranychus urticae</Emphasis> (Acari: Tetranychidae)

The effect of fungal infection on the reproductive potential of two-spotted spider mite, Tetranychus urticae, was evaluated as part of the full biocontrol potential of three entomopathogenic fungi by modeling of fecundity probability. Female mites (≤2-day-old) on leaves were exposed to the sprays of Beauveria bassiana, Paecilomyces fumosoroseus and Metarhizium anisopliae at the concentrations of 1.13 × 10³, 1.55 × 10³ and 0.95 × 10³ deposited conidia mm⁻² and then individually reared at 25°C and 12:12 L:D for oviposition. Mite mortalities 10 days after spraying were 73.1, 75.4 and 67.9% in the fungal treatments versus 15.5% in control. On average, females infected by the three fungal species survived 5.8, 6.2 and 6.3 days, and laid 3.1, 4.0 and 4.0 eggs per capita, respectively. These were 3–4 fold lower than the control fecundity at 12.3. The cumulative probabilities [P(m ≤ N)] for the counts of infected and non-infected (control) females laying m eggs per capita (m ≤ N) during 10 days fit very well the equation P(m ≤ N) = 1/[1 + exp(a + bm)] (r ² ≥ 0.98), yielding a solution to the probability for the female mites to achieve a specific fecundity {P(m ≤ N)−P[m ≤ (N − 1)]}. Consequently, the infected mites had 71–78% chance to lay ≤5 eggs per capita but only 5–8% to deposit >10 eggs despite some variation among the tested fungi. In contrast, the chances for the non-infected mites to achieve the low and high fecundities were 23 and 55%. The fitted probabilities provide a full coverage of the fecundity potential of infected versus non-infected mites and are more informative than the mean fecundities.     

Karyological studies in <Emphasis Type="Italic">Deschampsia antarctica</Emphasis> Desv. (Poaceae)

Deschampsia antarctica Desv. (Poaceae), known as Antarctic hairgrass, is the only grass species and one of the two vascular plant species native to Antarctica and it is a valuable source for gene discovery associated with freezing-tolerance. In this work the karyotype of D. antarctica collected near Jubany Antarctic Base was reported for the first time. This species presents a chromosome number of 2n = 2x = 26, with karyotypic formula 10m + 6sm + 8st + 2t. The nucleolar organizer region is located in the short arm in one of the submetacentric pairs forming a terminal satellite. Aneusomaty, a phenomenon already reported in the genus, was detected during this study. The cytogenetic information, together with the recent phylogenetic data will be useful for breeding strategies in agronomically valuable crops.     

Growth of <Emphasis Type="Italic">Trametes versicolor</Emphasis> on phenol

Trametes versicolor 1 was shown to grow on phenol as its sole carbon and energy source. The culture growth and degradation ability dependence on culture medium pH value was observed. The optimal pH value of a liquid Czapek salt medium was 6.5. The investigated strain utilized completely 0.5 g/l phenol in 6 days. The dynamics of the phenol degradation process was investigated. The process was characterized by specific growth rate μ_max 0.33 h⁻¹, metabolic coefficient k = 4.4, yield coefficient Y _x/s  = 0.23 and rate of degradation Q = 0.506 h⁻¹. The intracellular activities of phenol hydroxylase (0.333 U/mg protein) and cis,cis-muconate lactonizing enzyme (0.41 U/mg protein) were demonstrated for the first time in this fungus. In an attempt to estimate the occurrence of gene sequences in T. versicolor 1 related to phenol degradation pathway a dot blot analysis with total DNA isolated from this strain was performed. Two synthetic oligonucleotides were used as hybridizing probes. One of the probes was homologous to the 5′end of phyA gene coding for phenol hydroxylase in Trichosporon cutaneum ATCC 46490. The other probe was created on the basis of cis,cis-muconate lactonizing enzyme coding gene in T. cutaneum ATCC 58094. The results of these investigations showed that T. versicolor 1 may carry genes similar to those of Trichosporon cutaneum capable to degrade phenol.     

Enhanced fructooligosaccharides and inulinase production by a <Emphasis Type="Italic">Xanthomonas campestris</Emphasis> pv. <Emphasis Type="Italic">phaseoli</Emphasis> KM 24 mutant

Xanthomonas campestris pv phaseoli produced an extracellular endoinulinase (9.24 ± 0.03 U mL⁻¹) in an optimized medium comprising of 3% sucrose and 2.5% tryptone. X. campestris pv. phaseoli was further subjected to ethylmethanesulfonate mutagenesis and the resulting mutant, X. campestris pv. phaseoli KM 24 demonstrated inulinase production of 22.09 ± 0.03 U mL⁻¹ after 18 h, which was 2.4-fold higher than that of the wild type. Inulinase production by this mutant was scaled up using sucrose as a carbon source in a 5-L fermenter yielding maximum volumetric (21,865 U L⁻¹ h⁻¹) and specific (119,025 U g⁻¹ h⁻¹) productivities of inulinase after 18 h with an inulinase/invertase ratio of 2.6. A maximum FOS production of 11.9 g L⁻¹ h⁻¹ and specific productivity of 72 g g⁻¹ h⁻¹ FOS from inulin were observed in a fermenter, when the mutant was grown on medium containing 3% inulin and 2.5% tryptone. The detection of mono- and oligosaccharides in inulin hydrolysates by TLC analysis indicated the presence of an endoinulinase. This mutant has potential for large-scale production of inulinase and fructooligosaccharides.     

Acaricidal effects of <Emphasis Type="Italic">Corymbia citriodora</Emphasis> oil containing <Emphasis Type="Italic">para</Emphasis>-menthane-3,8-diol against nymphs of <Emphasis Type="Italic">Ixodes ricinus</Emphasis> (Acari: Ixodidae)

The toxicity of para-menthane-3,8-diol (PMD), the main arthropod-repellent compound in the oil of the lemon eucalyptus, Corymbia citriodora, was evaluated against nymphs of Ixodes ricinus using five methods (A–E) of a contact toxicity bioassay. Mortality rates were estimated by recording numbers of dead nymphs at 30 min intervals during the first 5 h after the start of exposure and at longer intervals thereafter. The mortality rate increased with increasing concentration of PMD and duration of exposure with a distinct effect after 3.5 h. From the results obtained by methods A, C and E, the LC₅₀ range was 0.035–0.037 mg PMD/cm² and the LC₉₅ range was 0.095–0.097 mg PMD/cm² at 4 h of exposure; the LT₅₀ range was 2.1–2.8 h and the LT₉₅ range was 3.9–4.2 h at 0.1 mg PMD/cm². To determine the duration of toxic activity of PMD, different concentrations (0.002, 0.01, 0.1 mg PMD/cm²) were tested and mortality was recorded at each concentration after 1 h; thereafter new ticks were tested. This test revealed that the lethal activity of PMD remained for 24 h but appeared absent after 48 h. The overall results show that PMD is toxic to nymphs of I. ricinus and may be useful for tick control.     

AFLP markers in the detection of Scirpus × mariqueter (CYPERACEAE) hybrid in China

Scirpus × mariqueter Tang & F.T. Wang (CYPERACEAE) is a pioneer plant of the tidal zone of estuaries of East Asia. Amplified fragment length polymorphisms (AFLP) were used to infer the relationship between S. × mariqueter and its putative progenitors, Scirpus planiculmis F. Schmidt and Scirpus triqueter L. The genetic distance between S. × mariqueter and S. triqueter was much higher than that between S. × mariqueter and S. planiculmis, and samples of S. × mariqueter and those of S. planiculmis did not form a monophyletic group, while the S. triqueter group formed a distinct monophyletic group. However, we also detected an apparent clustering of individuals of S. × mariqueter and S. planiculmis separately. Our results disprove the hybrid origin of S. × mariqueter and rather suggest that it is more closely related to S. planiculmis.     

Genetic transformation and regeneration of transgenic plants from precultured cotyledon and hypocotyl explants of <Emphasis Type="Italic">Eucalyptus tereticornis</Emphasis> Sm. using <Emphasis Type="Italic">Agrobacterium tumefaciens</Emphasis>

An efficient transformation protocol was developed for Eucalyptus tereticornis Sm. using cotyledon and hypocotyl explants. Precultured cotyledon and hypocotyl explants were cocultured with Agrobacterium tumefaciens strain LBA 4404 harboring the binary vector pBI121 containing the uidA and neomycin phosphotransferase II genes for 2 d and transferred to selective regeneration medium containing 0.5 mg/l 6-benzylaminopurine (BAP), 0.1 mg/l naphthalene acetic acid, 40 mg/l kanamycin, and 300 mg/l cefotaxime. After two passages in the selective regeneration medium, the putatively transformed regenerants were transferred to Murashige and Skoog (MS) liquid medium containing 0.5 mg/l BAP and 40 mg/l kanamycin on paper bridges for further development and elongation. The elongated kanamycin-resistant shoots were subsequently rooted on the MS medium supplemented with 1.0 mg/l indole-3-butyric acid and 40 mg/l kanamycin. A strong β-glucuronidase activity was detected in the transformed plants by histochemical assay. Integration of T-DNA into the nuclear genome of transgenic plants was confirmed by polymerase chain reaction and southern hybridization. This protocol allows effective transformation and direct regeneration of E. tereticornis Sm.     

Optimized expression of an acid xylanase from <Emphasis Type="Italic">Aspergillus usamii</Emphasis> in <Emphasis Type="Italic">Pichia pastoris</Emphasis> and its biochemical characterization

The xylanase gene xyn II from Aspergillus usamii E001 was placed under the control of an alcohol oxidase promoter (AOX1) in the plasmid pPIC9K and integrated into the genome of a methylotrophic yeast, P. pastoris GS115, by electroporation. His⁺ transformants were screened for on the basis of their resistance to G418 and activity assay. A transformant, P. pastoris GSC12, which showed resistance to over 6 mg G418/ml and highest xylanase activity was selected. Recombinant xylanase was secreted by P. pastoris GSC12 24 h after methanol induction of shake-flask cultures, and reached a final yield of 3139. About 68 U/mg 120 h after the induction. The molecular mass of this xylanase was estimated to be 21 kDa by SDS-PAGE. The optimum pH and temperature were 4.2 and 50 °C, respectively. Xylanase was stable below 50 °C and within pH 3.0–7.0. Its activity was increased by EDTA and Co²⁺ ion and strongly inhibited by Mn²⁺, Li⁺ and Ag⁺ ions. The K _m and V _max values with birchwood xylan as the substrate were found to be 5.56 mg/ml and 216 μmol/mg/min, respectively. This is the first report on expression and characterization of xylanase from A. usamii in P. pastoris. The hydrolysis products consisted of xylooligosaccharides together with a small amount of xylose. This property made the enzyme attractive for industrial purposes, as relatively pure xylooligosaccharides could be obtained.     

Age and growth of <Emphasis Type="Italic">Schizothorax waltoni</Emphasis> in the Yarlung Tsangpo River in Tibet,China

Age and growth were studied for Schizothorax waltoni in the middle reaches of the Yarlung Tsangpo River in Tibet, southwest of China, from April 2004 to September 2006. A total of 201 specimens were collected ranging from 110 to 580 mm in standard length (SL). In contrast to other otoliths, sectioned lapillus showed a clear pattern of alternating opaque and hyaline zones. Marginal increment analyses showed that the increments, each composed of one opaque and one hyaline zone, are deposited annually. Opaque edges were prevalent from May to August. The von Bertalanffy growth parameters based on sectioned otolith data were L _t  = 689.8{1 − exp[0.051 (t + 3.275)]} for males, and L _t  = 691.1{1 − exp[0.056 (t + 2.466)]} for females. The slow growth and long life indicate that S. waltoni is vulnerable to overfishing and that harvesting strategies for the species should be conservative.     

Isolation and characterization of porins from <Emphasis Type="Italic">Desulfovibrio piger</Emphasis> and <Emphasis Type="Italic">Bilophila wadsworthia</Emphasis>: structure and gene sequencing

The outer membrane proteins of Desulfovibrio piger and Bilophila wadsworthia (Omp-DP and Omp-BW, respectively) and the genes encoding them (omp-DP and omp-BW) were isolated and characterized. Native Omp-DP and Omp-BW form a trimeric structure of approximately 120 kDa. These proteins disaggregated into monomers with a molecular weight of approximately 53 kDa after heating at 95°C for 10 min. The pore-forming abilities of these oligomeric proteins demonstrated that they form small nonspecific channels with an exclusion limit of 260–300 Da. The omp-DP and omp-BW genes were cloned and sequenced. Sequence analyses revealed an open reading frame of 1,512 bp for omp-DP and 1,440 bp for omp-BW. The mature Omp-DP protein consisted of 480 amino acids and had a calculated MW of 53,290 Da. The mature Omp-BW protein consisted of 456 amino acids and had a calculated MW of 50.050 Da. Alignment of Omp-DP with Omp-BW revealed 54% homology, whereas alignment with other known porins showed a low level of homology. Analysis of the secondary structures indicated that both proteins span the outer membrane 18 times with amphipathic β-strands. This research presents porins which were isolated and characterized for the first time from bacteria belonging to the Desulfovibrionaceae family. O. Avidan and E. Kaltageser have contributed equally to this work.     

The suitability of non-target native mangroves for the survival and development of the lantana bug <Emphasis Type="Italic">Aconophora compressa</Emphasis>, an introduced weed biological control agent

Aconophora compressa (Hemiptera: Membracidae), a biological control agent introduced against the weed Lantana camara (Verbenaceae) in Australia, has since been observed on several non-target plant species, including native mangrove Avicennia marina (Acanthaceae). In this study we evaluated the suitability of two native mangroves, A. marina and Aegiceras corniculatum (Myrsinaceae), for the survival and development of A. compressa through no-choice field cage studies. The longevity of females was significantly higher on L. camara (57.7 ± 3.8 days) than on A. marina (43.3 ± 3.3 days) and A. corniculatum (45.7 ± 3.8 days). The proportion of females laying eggs was highest on L. camara (72%) followed by A. marina (36%) and A. corniculatum (17%). More egg batches per female were laid on L. camara than on A. marina and A. corniculatum. Though more nymphs per shoot emerged on L. camara (29.9 ± 2.8) than on A. marina (13 ± 4.8) and A. corniculatum (10 ± 5.3), the number of nymphs that developed through to adults was not significantly different. The duration of nymphal development was longer on A. marina (67 ± 5.8 days) than on L. camara (48 ± 4 days) and A. corniculatum (43 ± 4.6 days). The results, which are in contrast to those from previous glasshouse and quarantine trials, provide evidence that A. compressa adults can survive, lay eggs and complete nymphal development on the two non-target native mangroves in the field under no-choice condition.     

Chromatic photoacclimation extends utilisable photosynthetically active radiation in the chlorophyll <Emphasis Type="Italic">d</Emphasis>-containing cyanobacterium, <Emphasis Type="Italic">Acaryochloris marina</Emphasis>

Chromatic photoacclimation and photosynthesis were examined in two strains of Acaryochloris marina (MBIC11017 and CCMEE5410) and in Synechococcus PCC7942. Acaryochloris contains Chl d, which has an absorption peak at ca 710 nm in vivo. Cultures were grown in one of the three wavelengths (525 nm, 625 nm and 720 nm) of light from narrow-band photodiodes to determine the effects on pigment composition, growth rate and photosynthesis: no growth occurred in 525 nm light. Synechococcus did not grow in 720 nm light because Chl a does not absorb effectively at this long wavelength. Acaryochloris did grow in 720 nm light, although strain MBIC11017 showed a decrease in phycobilins over time. Both Synechococcus and Acaryochloris MBIC11017 showed a dramatic increase in phycobilin content when grown in 625 nm light. Acaryochloris CCMEE5410, which lacks phycobilins, would not grow satisfactorily under 625 nm light. The cells adjusted their pigment composition in response to the light spectral conditions under which they were grown. Photoacclimation and the Q _y peak of Chl d could be understood in terms of the ecological niche of Acaryochloris, i.e. habitats enriched in near infrared radiation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Effects of <Emphasis Type="Italic">Lactobacillus buchneri</Emphasis> and <Emphasis Type="Italic">Lactobacillus plantarum</Emphasis> on fermentation,aerobic stability,bacteria diversity and ruminal degradability of alfalfa silage

Silages are important feedstuffs. Homofermentative lactic acid bacterial inoculants are often used to control silage fermentation. However, some research pointed out those homofermentative lactic acid bacteria (LAB) impaired the aerobic stability of wheat, sorghum, and corn silages. Adding heterofermentative LAB can produce more acetic acid, thereby stabilizing silages during aerobic exposure. Alfalfa is difficult to ensile. The present work was to study the effects of L. buchneri (heterofermentative LAB), alone or in combination with L. plantarum (homofermentative LAB) on the fermentation, aerobic stability, bacteria diversity and ruminal degradability of alfalfa silage. After 90 days ensiling, the pH, NH₃-N/TN, butyric acid content and molds counts of control were the highest. The inoculated silages had more lactic acid, acetic acid content and more lactic acid bacteria than the control. Inoculating LAB inhibited harmful microorganisms, such as Enterobacterium and Klebsiella pneumoniae. The L. buchneri + L. plantarum-inoculated silage had more acetic acid and less yeasts than other three treatments (P < 0.05), and lower NH₃-N/TN than control (P < 0.05). The CO₂ production of L. buchneri + L. plantarum-inoculated silage was less than that of L. plantarum-inoculated silage (P < 0.05). Inoculating LAB in alfalfa silages can decrease pH, increase the production of lactic and acetic acids, reduce the number of yeasts and molds, and inhibit Enterobacterium and K. pneumoniae. Inoculating with L. buchneri or L. buchneri + L. plantarum can improve aerobic stability of alfalfa silages. A combination of L. buchneri and L. plantarum is preferable because it enhanced alfalfa silage quality and aerobic stability.     

Production and characterization of intergeneric somatic hybrids between <Emphasis Type="Italic">Brassica napus</Emphasis> and <Emphasis Type="Italic">Orychophragmus violaceus</Emphasis> and their backcrossing progenies

Alien chromosome addition lines have been widely used for identifying gene linkage groups, assigning species-specific characters to a particular chromosome and comparing gene synteny between related species. In plant breeding, their utilization lies in introgressing characters of agronomic value. The present investigation reports the production of intergeneric somatic hybrids Brassica napus (2n = 38) + Orychophragmus violaceus (2n = 24) through asymmetric fusions of mesophyll protoplasts and subsequent development of B. napus-O. violaceous chromosome addition lines. Somatic hybrids showed variations in morphology and fertility and were mixoploids (2n = 51–67) with a range of 19–28 O. violaceus chromosomes identified by genomic in situ hybridization (GISH). After pollinated with B. napus parent and following embryo rescue, 20 BC₁ plants were obtained from one hybrid. These exhibited typical serrated leaves of O. violaceus or B. napus-type leaves. All BC₁ plants were partially male fertile but female sterile because of abnormal ovules. These were mixoploids (2n = 41–54) with 9–16 chromosomes from O. violaceus. BC₂ plants showed segregations for female fertility, leaf shape and still some chromosome variation (2n = 39–43) with 2–5 O. violaceus chromosomes, but mainly containing the whole complement from B. napus. Among the selfed progenies of BC₂ plants, monosomic addition lines (2n = 39, AACC + 1O) with or without the serrated leaves of O. violaceus or female sterility were established. The complete set of additions is expected from this investigation. In addition, O. violaceus plants at diploid and tetraploid levels with some variations in morphology and chromosome numbers were regenerated from the pretreated protoplasts by iodoacetate and UV-irradiation. Z. Zhao and T. Hu make equal contributions to this work.