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[Objective] The paper was to provide scientific basis for popularization and application of 70% Thiamethoxam ZF. [Method] 70% Thiamethoxam ZF was selected and applied in the soil for controlling Ceratovacuna lanigera Zehntner and Baliathrips serratus Kobus. [Result] 70% Thiamethoxam ZF had good control effect against C. lanigera and B. serratus. The optimum dosage of 70% Thiamethoxam ZF was 450 g/hm²(effective ingredients 315 g). 70% Thiamethoxam ZF (dosage per hm²) mixed with the regular fertilizer (dosage per hm²) should be applied together in sugarcane planting and management from February to June. The control effects against C. lanigera and B. serratus were above 98.4% and 82.9% respectively. The actual yield and sugar content were increased by more than 34 290 kg/hm² and 6.8% respectively compared to blank control. [Conclusion] 70% Thiamethoxam ZF was a new ideal pesticide with characteristics of sustainedrelease, long-lasting and low-toxic for controlling C. lanigera and B. serratus, and should be applied widely in the sugarcane planting area. [ABSTRACT FROM AUTHOR]

The synthesis and post-synthesis separation of nanoparticles that are polydispersed in size and shape is important due to their variety of applications. In the present study, it is demonstrated that the Magnolia kobus plant extract produces a diverse mixture of extracellular gold and silver nanocrystals with a majority of polydispersed spheres; however, there are a significant number of homogeneously sized triangles, pentagons, and hexagons. The gold and silver nanoparticles synthesized using the M. kobus plant extract can be separated using density gradient centrifugation in the size range of 52 ∼ 117 nm and 38 ∼ 61 nm, respectively. The average particle sizes increase with increases in the sucrose concentration of each layer. Relatively larger but long, thin plates of gold nanoparticles appear in the higher density sediments, whereas a larger proportion of smaller spheres featured in the lower density gradients. Similarly, silver nanospheres of different sizes are separated at different density gradients with smaller proportions of plates. [ABSTRACT FROM AUTHOR]

The article describes the Bovidae (Mammalia) species from the lower Pliocene in Kossom Bougoudi (KB) and Kollé (KL) in Chad. Most of the specimens analyzed are consist of isolate teeth, incomplete horn-cores and limb bones and evidence of wind abrasion. The holotype, paratype, derivato nominis and diagnosis of each Bovidae species are discussed, including Tchadotragus fanonei, Kobus, Aepyceros, Jamous kolleensis and Gazella. According to the authors, the assemblages in KB and KL document the gradual replacement of hippotragines by alcelaphines. A comparison between the KB and KL Bovidae with those from Sahabi, Libya is also presented.

Reproductive effort should negatively correlate with reproductive value, yielding a pattern of increased effort with age. According to the terminal investment hypothesis, females near the end of their reproductive life span should devote more resources to reproduction than those near the start of their reproductive careers. We tested predictions of the terminal investment hypothesis by evaluating 38 years of reproductive life-history data collected from Nile lechwe (Kobus megaceros), an ungulate species living at San Diego Zoo's Wild Animal Park. The maximum reproductive success of Nile lechwe matched predictions of models of lifetime reproductive effort, with the relative mass of newborn calves providing an accurate indicator of the costs of reproduction. Newborn mass was significantly correlated with maternal age, and neonatal males tended to be heavier than neonatal females. Older dams were more likely to produce sons than daughters, dams that produced sons were more likely to die than were dams that produced daughters, and male calves were less likely to survive than were female calves. We conclude that young females endure a fertility cost while breeding, whereas older females encounter a survivorship cost, associated with progeny production. Our findings support the terminal investment hypothesis, and we suggest that secondary sex ratio bias among older female Nile lechwe reflects the evolution of a flexible life-history strategy promoting production of costly male calves when reproductive value is declining. [ABSTRACT FROM AUTHOR]

The article offers information on the research conducted on the intra-tooth enamel stable isotopes of waterbuck Kobus ellipsiprymnus at the Queen Elizabeth National Park (QENP) in Uganda. Researchers found that waterbuck Kobus ellipsiprymnus (K. e.), comprise two genetically distinct subspecies K. e. ellipsiprymnus and K. e. defassa, which are known to be predominantly grazers, which browse in their diet, especially during the dry season when grasses become higher in structural components and lower in protein. Carbon isotope ratio data confirm that defassa waterbuck in the QENP consume mainly C4 grass but include some C3 browse in its diets.

Mitochondrial DNA control region sequences and seven microsatellites were used to estimate the genetic structuring, evolutionary history and historic migration patterns of the kob antelope ( Kobus kob). Ten populations were analysed, representing the three recognized K. kob subspecies: K. k. kob in west Africa, K. k. thomasi in Uganda and K. k. leucotis in Sudan and Ethiopia. Despite being classified as K. k. thomasi and being phenotypically identical to the kob in Queen Elizabeth National Park (NP), the Murchison Falls population in Uganda showed high genetic similarity with the phenotypically distinct K. k. leucotis populations in Sudan and Ethiopia. This was regardless of marker type. Pairwise comparisons and genetic distances between populations grouped Murchison with K. k. leucotis, as did the Bayesian analysis, which failed to find any genetic structuring within the group. We propose that the divergent phenotype and life-history adaptations of K. k. leucotis reflect the isolation of kob populations in refugia in west and east Africa during the Pleistocene. Subsequent dispersal has led to secondary contact and hybridization in northern Uganda between lineages, which was supported by high levels of genetic diversity in Murchison. The reduced variability observed in Queen Elizabeth NP reflects a small founder population from west Africa and in part the decimation of Uganda's wildlife during the country's political turmoil in the 1970s. Due to similarities in phenotype and ecology, and the joint evolutionary history of their mtDNA sequences, the taxonomic status of K. k. kob and K. k. thomasi as separate subspecies is called into question. [ABSTRACT FROM AUTHOR]

The genetic differentiation among kob populations (Kobus kob) representing two recognized subspecies was examined using mitochondrial control region sequences. Two distinct lineages (estimated sequence divergence of 9.8%) exhibited different geographical distributions and do not coincide with previously recognized ranges of subspecies. The presence of the two lineages was further supported with sequences of mitochondrial cytochrome b gene. One lineage was predominant in the west and southern ranges of the populations studied and the other was commonly found in a more northern distribution (Murchison populations) in Uganda. Murchison and the geographically intermediate Toro populations (Uganda) represented the area of overlap. The existence of the two lineages in the area of overlap is hypothesized to have resulted from a range expansion and secondary contact of the two lineages of kob that evolved in allopatry. The existence of the kob during the Pleistocene offers a plausible explanation for the observed biogeographic pattern. Our mitochondrial data reveal two examples of discordance between a gene tree and presumed species tree as: (i) the two lineages co-occur in the kob subspecies, Kobus kob thomasi (Uganda kob); and (ii) the puku, which was included in the analysis because of its controversial taxonomic status (currently recognized as a distinct species from the kob), is paraphyletic with respect to the kob. Significant degrees of heterogeneity were detected between populations. Relatively high genetic variation was observed in the populations, however, the inclusion of distinct lineages influences the population structure and nucleotide diversity of the kob populations. [ABSTRACT FROM AUTHOR]

G- and C-banded karyotypes of four species of the genus Kobus were compared using the standard karyotype of Bos taurus . Chromosomal complements were 2n = 50–54 in K. ellipsiprymnus , 2n = 50 in K. kob , 2n = 48 in K. leche , and 2n = 52 in K. megaceros . The number of autosomal arms in all karyotypes was 58. Fifteen autosomal pairs were conserved among these four species, including the 1;19 and 2;25 centric fusions, and autosomal differences involved eight centric fusion rearrangements. Five centric fusions were each unique to a particular taxon: 3;10 (K. leche ), 3;11 and 6;29 (K. kob ), and 5;17 and 7;11 (K. ellipsiprymnus ). The 4;7 fusion occurred in K. leche and K. megaceros , whereas the 5;13 fusion occurred in K. kob and K. leche ; the 6;18 fusion was found in three species but was absent in K. kob . Differences between the X chromosomes of the four Kobus species were attributed to heterochromatic additions or deletions, and Y-chromosome differences may have been the result of pericentric inversion. G-banded karyotypes of putative K. l. leche and K. l. kafuensis appeared identical, as did C-banded karyotypes of the two subspecies. Karyotypes of K. e. ellipsiprymnus and K. e. defassa differed as a result of the 6;18 centric fusion, which was polymorphic in K. e. defassa , and the 7;11 centric fusion, which was polymorphic in K. e. ellipsiprymnus but absent in K. e. defassa . Several centric fusions were related by monobrachial chain-IV complexes; however, records of hybridization indicate that reproductive isolation between at least certain species of Kobus is incomplete. Karyotypic differences between K. ellipsiprymnus (including K. e. ellipsiprymnus and K. e. defassa ), K. kob , K. leche , and K. megaceros support the validity of these taxa, as well as the need to manage them as separate populations. Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract The kob (Kobus kob kob ) population studied in the Comoé National Park, Ivory Coast, suffered unsustainable losses to poaching before and during the investigation. This in turn did not only lead to low densities but also changed the population composition, resulting in a strong female bias in all age classes except juveniles. The relative rarity of adult males probably had negative effects on the population recruitment. Although mating occurred throughout the year and birth intervals were short, at least in some females, annual birth-rate was low compared to earlier studies in the same area. Effective conservation measures are urgently needed to ensure the future existence of the studied population. [ABSTRACT FROM AUTHOR]