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Wild cotton species are an important source of desirable genes for genetic improvement of cultivated cottonGossypium hirsutumLinnaeus, 1763. For the success of such an improvement, chromosome pairings and recombinations in hybrids are fundamental. The wild African speciesG. longicalyxHutchinson & Lee, 1958 could be used as donor of the desirable trait of fiber fineness. Twelve BC1 plants obtained from the backcrossing of [(G. hirsutum×G. thurberiTodaro, 1877)2×G. longicalyx] (AhDhD1F1, 2n = 4x = 52) trispecies hybrid (HTL) byG. hirsutum(cv. C2) (AhAhDhDh, 2n = 4x = 52) were investigated for meiotic behaviour and plant fertility. Their chromosome associations varied as follows: (2.5 to 11.5) I + (17 to 22) II + (0.31 to 1.93) III + (0.09 to 1.93) IV + (0 to 0.07) V + (0 to 0.14) VI. Their pollen fertility ranged from 4.67 to 32.10 %. Only four BC1 plants produced a few seeds through self-pollination. The remaining BC1 were totally self-sterile and usually presented the highest number of univalents. All BC1 materials produced BC2 seeds (0.44 to 6.50 seeds per backcross) with the number of seeds negatively correlated with the number of univalents (R2= 0.45, P < 0.05). Most BC1 plants gave significantly finer fiber compared to the cultivatedG. hirsutum. SSR markers showed a segregation of wild alleles among the backcross derivatives and Genomicin situhybridization (GISH) revealed presence of entire chromosomes ofG. longicalyxas well as recombinant chromosomes in the backcross derivatives. The significance and details of these results are presented and the prospects of successfully exploiting these plant materials are discussed.

Background and objective Prior small-scale clinical trials showed that Artemisia annua and Artemisia afra infusions, decoctions, capsules, or tablets were low cost, easy to use, and efficient in curing malaria infections. In a larger-scale trial in Kalima district, Democratic Republic of Congo, we aimed to show A. annua and/or A. afra infusions were superior or at least equivalent to artesunate-amodiaquine (ASAQ) against malaria. Methods A double blind, randomized clinical trial with 957 malaria-infected patients had two treatment arms: 472 patients for ASAQ and 471 for Artemisia (248 A. annua, 223 A. afra) remained at end of the trial. ASAQ-treated patients were treated per manufacturer posology, and Artemisia-treated patients received 1 l/d of dry leaf/twig infusions for 7 d; both arms had 28 d follow-up. Parasitemia and gametocytes were measured microscopically with results statistically compared among arms for age and gender. Results Artemisinin content of A. afra was negligible, but therapeutic responses of patients were similar to A. annua-treated patients; trophozoites cleared after 24 h, but took up to 14 d to clear in ASAQ-treated patients. D28 cure rates defined as absence of parasitemia were for pediatrics 82, 91, and 50% for A. afra, A. annua and ASAQ; while for adults cure rates were 91, 100, and 30%, respectively. Fever clearance took 48 h for ASAQ, but 24 h for Artemisia. From D14-28 no Artemisia-treated patients had microscopically detectable gametocytes, while 10 ASAQ-treated patients remained gametocyte carriers at D28. More females than males were gametocyte carriers in the ASAQ arm but were unaffected in the Artemisia arms. Hemoglobin remained constant at 11 g/dl for A. afra after D1, while for A. annua and ASAQ it decreased to 9-9.5 g/dl. Only 5.0% of Artemisia-treated patients reported adverse effects, vs. 42.8% for ASAQ. Conclusion A. annua and A. afra infusions are polytherapies with better outcomes than ASAQ against malaria. In contrast to ASAQ, both Artemisias appeared to break the cycle of malaria by eliminating gametocytes. This study merits further investigation for possible inclusion of Artemisia tea infusions as an alternative for fighting and eradicating malaria.

Background and objective Schistosomiasis (bilharzia), a serious neglected tropical disease affecting millions, has few cost-effective treatments, so two Artemisia wormwood species, A. annua and A. afra, were compared with the current standard praziquantel (PZQ) treatment in an 800 patient clinical trial, August-November of 2015. Methods The double blind, randomized, superiority clinical trial had three treatment arms: 400 for PZQ, 200 for A. annua , and 200 for A. afra. PZQ-treated patients followed manufacturer posology. Artemisia -treated patients received 1 l/d of dry leaf/twig tea infusions divided into 3 aliquots daily, for 7 days with 28-day follow-up. Results Of 800 enrolled patients having an average of >700 Schistosoma mansoni eggs per fecal sample, 780 completed the trial. Within 14 days of treatment, all Artemisia -treated patients had no detectable eggs in fecal smears, a result sustained 28 days post treatment. Eggs in fecal smears of PZQ-treated patients were undetectable after D21. More males than females who entered the trial had melena, but both genders responded equally well to treatment; by D28 melena disappeared in all patients. In all arms, eosinophil levels declined by about 27% from D0 to D28. From D0 to D28 hemoglobin increases were greater in PZQ and A. afra -treated patients than in A. annua -treated patients. Hematocrit increases were greater from D0 to D28 for patients treated with either PZQ or A. annua compared to those treated with A. afra . Gender comparison showed that A. afra –treated males had significantly greater hemoglobin and hematocrit increases by D28 than either PZQ or A. annua –treated males. In contrast, PZQ and A. afra -treated females had greater hemoglobin and hematocrit increases than A. annua -treated females. Both adults and pediatric patients treated with A. annua responded better compared to PZQ treatment. Conclusion Both A. annua and A. afra provided faster effective treatment of schistosomiasis and should be considered for implementation on a global scale.

En vue d’évaluer les performances de production de Jatropha curcas L. en conditions de sols pauvres, un essai a été réalisé entre juillet 2009 et décembre 2012 sur le plateau des Batéké dans les sites de Mbankana et de Mongata à proximité de Kinshasa. Les résultats obtenus montrent des différences significatives (p

Cotton (Gossypium spp.) is the leading natural fiber crop in the world. The genus Gossypium comprises a broad genetic base that has been and continues to be actively studied by cotton genetists and breeders. Cytogenetic tools play an important role in cotton genome research and cotton breeding. Based essentially on the observation of chromosome morphologies and the analysis of chromosome pairing, classical cytogenetics has contributed greatly to understanding cotton history, taxonomy and phylogeny, and has been a great help in cotton breeding programs designed to transfer desired genes from alien species into cultivated varieties. With the advent of molecular cytogenetics in the 1980s, the field of cytogenetics has been revolutionized. Beside an increase in the speed, sensitivity and specificity of conventional cytogenetic techniques, molecular cytogenetics offers opportunities to perform a variety of tasks not achievable by classical methods. These tasks include analysis of the distribution of repeated sequences along the genome, assignment of repetitive and single copy DNA sequences to positions on chromosomes, determination of the relationship between specific chromosomes and linkage groups, determination of the relationships between physical and genetic distances, differentiation of the genomes involved in hybrids, detection of alien DNA in introgressed lines, and others. We summarize the achievements of classical and molecular cytogenetic investigations in Gossypium and underline the relevance of bridging these approaches in Gossypium genetic studies and exploitation.

Correspondance: mergeai.g@fsagx.ac.be; International audience; A three-species hybrid named HTL including Gossypium hirsutum L. [2n = 4 x = 52, (AD)1 genome] was created using the pseudophyletic introgression method with G. longicalyx Hutch. & Lee (2n = 2x = 26, F1 genome) as donor parent and G. thurberi Tod. (2n = 2x = 26, D1 genome) as bridge species. The new hybrid was totally self-sterile and its interspecific status was confirmed using simple sequence repeat markers and cytogenetic analysis. Cytogenetic studies showed that its chromosome configuration was 2n = 52 = 14.13 I + 15.10 II + 1.03 III + 0.9 IV + 0.03 V + 0.13 VI (where I, II, III, IV, V and VI are univalents, bivalents, trivalents, tetravalents, pentavalents and hexavalents, respectively). Prospects for successfully exploiting the HTL hybrid in breeding programmes are discussed.

Genetic barriers often prevent exploiting diploid cotton germplasm for the improvement of tetraploid cotton. The objective of this study was to investigate mating schemes to achieve introgression of Gossypium sturtianum J.H. Willis and G. australe F. Muell diploid cottons into tetraploid G. hirsutum L. Gossypium hirsutum x G. sturtianum and G. hirsutum x G. australe hexaploids were backcrossed to G. hirsutum to produce BC1 pentaploids and BC2 and BC1S1 euploid and aneuploid plants. The use of G. hirsutum x G. australe pentaploids as male parent in backcrosses with G. hirsutum allowed the production of an important progeny of BC2 self fertile plants that were euploid or carried one chromosome of G. australe in addition to the 52 chromosomes of G. hirsutum. The only two BC2 fertile plants issued from G. hirsutum x G. sturtianum hybrids were monosomic addition materials. Both of them were obtained with the pentaploid as female parent in the backcross to cv. Stam F. These results confirm that cotton male gametes are more limited than female gametes in the number of supernumerary chromosomes they can carry. This provides a means of developing alien monosomic addition lines in the G. hirsutum background from all the diploid species of Gossypium whose chromosomes do not carry genes preventing their individual male transfer. The analysis of the monosomic addition plants produced from the G. hirsutum x G. australe hexaploid with simple sequence repeat (SSR) markers allowed us to distinguish seven lines carrying different single chromosomes of G. australe. These lines constitute valuable materials with which to carry out fundamental and applied genetic investigations. (Resume d'auteur)