ABSTRACT The world collection of sugarcane (Saccharum hybrids. and related grasses (WCSRG) is an important source of genes for sugarcane and energycane breeding. The core collection or diversity panel of the WCSRG was created in Canal Point with 300 accession and 10 checks to evaluate its diversity. The fiber components of the species and accessions within the WCSRG are unknown, so a shredded and dried fiber sample was taken from each accession and sent for fiber analysis. The acetyl groups, acid insoluble lignin, acid soluble lignin, arabinan, glucan, holocellulose, total lignin, structural ash, and xylan were quantified on a % fiber basis and nonstructural ash on a % total basis. There were significant, but not large differences between species for holocellulose, lignin, acetyl, acid soluble lignin, nonstructural ash, and glucan. For each trait, Saccharum spontaneum had significantly more holocellulose, glucan, lignin, and nonstructural ash and less acetyl and acid soluble lignin than other species. In all populations, glucan and holocellulose were positively correlated and glucan and lignin were negatively correlated. In hybrids, internode length correlated positively with holocellulose and nonstructural ash and negatively with lignin. Principal component analysis indicated that a large amount of diversity exists within each of the species. The results suggest that strategic use of the WCSRG could provide both positive and negative selection for fiber-related traits could be made within all species of the collection.

A elevação da quantidade de mudas de alta qualidade associada ao descarte das de baixa qualidade pode aprimorar os programas de seleção e melhoramento genético da cana-de-açúcar (Saccharum spp.). Este trabalho avaliou a capacidade do método Dynamic Technique for Order Preference by Similarity to Ideal Solution (DTOPSIS) de identificar famílias da cana-de-açúcar com elevada qualidade. As características avaliadas foram: Brix, aptidão para moagem, diâmetro do caule, altura e porcentagem de tecido parenquimatoso. Os dados foram coletados em dois experimentos com 17 famílias e duas cultivares incluindo cana soca e brota. O DTOPSIS estima o índice Ci que expressa a proximidade de uma solução particular à ideal. O Ci foi utilizado para avaliar a distância de cada família à família ideal. As demais mudas foram utilizadas em um programa tradicional de seleção. Os valores de Ci de cada família foram comparados às taxas de seleção de famílias obtidas pelo programa tradicional de seleção por meio da estimação das taxas de seleção nos estágios 1 a 4. Os resultados indicaram que os valores de Ci calculados a partir dos experimentos foram significativamente correlacionados (p<0,01) às taxas de seleção do estágio 2 (r=0,8059), estágio 3 (r=0,7967) e estágio 4 (r=0,8202). Os resultados também indicaram que clones com promissor uso apresentam elevados valores de Ci. Conclui-se, portanto, que o método DTOPSIS é apropriado para selecionar e descartar mudas de alta e baixa qualidade, respectivamente, podendo elevar a eficiência dos programas de seleção.

Enlarging the quantity of seedlings of elite families and discarding inferior sugarcane (Saccharum spp.) families could improve sugarcane breeding and selection efficiency. The feasibility of using the method Dynamic Technique for Order Preference by Similarity to Ideal Solution (DTOPSIS) method was explored to identify superior sugarcane families. Data on 5 traits: Brix, millable stalks per stool (MS), stalk diameter (SD), plant height (PH), and percent pith were collected from two family trials having 17 families and two check cultivars at two sites including plant-cane and first-ratoon crops. The rest of the seedlings were planted into field for routine selection in the regular program. The DTOPSIS method calculates a comprehensive index (Ci) which expresses the closeness of a solution to the ideal solution and was used in this study to test the distance of each family to the ideal family. The Ci of the families was compared to the family selection rate in the regular program by determining the selection rate at Stage 1 to Stage 4 for each family in the regular program. The result indicated that the Ci values calculated from family trials were significantly (p<0.01) correlated to the selection rate at Stage 2 (r=0.8059), Stage3 (r=0.7967), and Stage 4 (r=0.8202), and indicating that promising clones were selected from families with higher Ci values in the family trial. Thus, it could be feasible to use DTOPSIS to determine elite sugarcane families and to eliminate inferior families and thereby, increasing the variety selection efficiency.

OBJECTIVE: To determine risk factors for poor birth outcome and their population attributable fractions. METHODS: 1688 women who attended for antenatal care were recruited into a prospective study of the effectiveness of syphilis screening and treatment. All women were screened and treated for syphilis and other reproductive tract infections (RTIs) during pregnancy and followed to delivery to measure the incidence of stillbirth, intrauterine growth retardation (IUGR), low birth weight (LBW) and preterm live birth. FINDINGS: At delivery, 2.7% of 1536 women experienced a stillbirth, 12% of live births were preterm and 8% were LBW. Stillbirth was independently associated with a past history of stillbirth, short maternal stature and anaemia. LBW was associated with short maternal stature, ethnicity, occupation, gravidity and maternal malaria whereas preterm birth was associated with occupation, age of sexual debut, untreated bacterial vaginosis and maternal malaria. IUGR was associated with gravidity, maternal malaria, short stature, and delivering a female infant. In the women who had been screened and treated for syphilis, in between 20 and 34% of women with each outcome was estimated to be attributable to malaria, and 63% of stillbirths were estimated as being attributable to maternal anaemia. Screening and treatment of RTIs was effective and no association was seen between treated RTIs and adverse pregnancy outcomes. CONCLUSION: Maternal malaria and anaemia continue to be significant causes of adverse pregnancy outcome in sub-Saharan Africa. Providing reproductive health services that include treatment of RTIs and prevention of malaria and maternal anaemia to reduce adverse birth outcomes remains a priority.

OBJETIVO: Identificar los factores de riesgo de desenlace adverso del parto y sus fracciones poblacionales atribuibles. MÉTODOS: En un estudio prospectivo sobre la eficacia de la detección y tratamiento de la sífilis se incluyeron 1688 mujeres que esperaban recibir atención prenatal. Todas ellas fueron sometidas a pruebas de detección y tratamiento de la sífilis y de otras infecciones del aparato reproductor durante el embarazo, y fueron observadas hasta el parto para determinar la incidencia de muerte fetal, retraso del crecimiento intrauterino, bajo peso al nacer y parto antes del término. RESULTADOS: Entre las 1536 mujeres observadas hasta el parto hubo un 2,7% de muertes fetales, un 12% de nacidos vivos antes del término y un 8% de recién nacidos con bajo peso al nacer. La muerte fetal se asoció de forma independiente a los antecedentes de muerte fetal y a la anemia y la baja estatura de la madre. El bajo peso al nacer se asoció a la baja estatura de la madre, su etnia y ocupación, el número de embarazos anteriores y los antecedentes de paludismo, mientras que el parto antes del término se asoció con la ocupación, la edad de inicio de las relaciones sexuales, la vaginosis bacteriana no tratada y los antecedentes de paludismo. El retraso del crecimiento intrauterino se asoció con el número de embarazos anteriores, el paludismo, la baja estatura de la madre y el sexo femenino del recién nacido. En estas mujeres sometidas a pruebas de detección y tratamiento de la sífilis, entre un 20 y un 34% de cada uno de los desenlaces adversos fueron atribuibles al paludismo, mientras que el 63% de las muertes fetales fueron atribuibles a la anemia materna. La detección y tratamiento de las infecciones del aparato reproductor fue eficaz y no se observó ninguna asociación entre las infecciones tratadas y los desenlaces adversos del embarazo. CONCLUSIÓN: El paludismo y la anemia materna siguen siendo causas importantes de desenlace adverso del embarazo en el África subsahariana. La prestación de servicios de salud reproductiva que incluyan el tratamiento de las infecciones del aparato reproductor y la prevención de la malaria y la anemia materna siguen siendo prioritarias para reducir los desenlaces adversos del embarazo.

OBJECTIF: Déterminer les facteurs de risque pour diverses issues défavorables de l'accouchement et les fractions attribuables en population de ces issues. MÉTHODES: 1688 femmes bénéficiant de soins anténataux ont été incluses dans une étude prospective visant à évaluer l'efficacité du dépistage de la syphilis et de son traitement. Pendant leur grossesse, ces femmes ont toutes été soumises à un dépistage de la syphilis et ont éventuellement été traitées contre cette maladie ou d'autres infections de l'appareil reproducteur. Elles ont également fait l'objet d'un suivi jusqu'à l'accouchement, en vue de mesurer l'incidence des mortinaissances, des retards de développement intra-utérins, des faibles poids à la naissance et des naissances avant terme. RÉSULTATS: Parmi les 1536 accouchements, 2,7 % ont donné un enfant mort-né, 12 % un enfant prématuré vivant et 8 % un enfant de faible poids à la naissance. La mortinaissance était associée de manière indépendante aux facteurs suivants : antécédents d'accouchement d'un enfant mort-né, et faible stature ou anémie maternelles. Le faible poids à la naissance pouvait être associé à une petite stature de la mère, à son origine ethnique, à sa profession, au nombre de grossesses et à la présence du paludisme chez la mère, tandis que la naissance avant terme pouvait être mise en relation avec la profession, l'âge au début de l'activité sexuelle et la présence d'une vaginite bactérienne non traitée ou d'un paludisme chez la mère. Le retard de croissance intra-utérin pouvait être corrélé avec le nombre de grossesses, la présence d'un paludisme chez la mère, une faible stature maternelle et la mise au monde d'une fille. Parmi les femmes chez lesquelles on avait détecté et traité une syphilis, 20 à 24 % des issues défavorables de l'accouchement ont été considérées comme imputables au paludisme et 63 % des mortinaissances à une anémie maternelle. Le dépistage et le traitement des infections de l'appareil reproducteur se sont révélés efficaces et aucune association n'a été relevée entre ces infections et des issues défavorables de la grossesse. CONCLUSION: Le paludisme et l'anémie maternels restent des causes importantes d'issues défavorables de la grossesse en Afrique subsaharienne. L'apport de services de santé génésique comprenant le traitement des infections de l'appareil reproducteur et la prévention du paludisme et de l'anémie chez la mère demeure une priorité pour réduire les issues défavorables de l'accouchement.