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This study aimed to determine the application methods of brassinosteroids (BR) as an alternative production system to improve plant growth and morpho-physiological characteristics of dry bean (Phaseolus vulgaris L.), soya bean (Glycine max (L.)), and groundnut (Arachis hypogaea L.). Trials were laid out in a complete randomized block design, arranged in a 4 x 2 factorial design. Brassinosteroids (100 g) treatments followed preventative and corrective treatments, where the dry bean, soya bean, and groundnut (three legumes) seeds were treated with BR; BR through the foliar application, soil drenching BR, and the control (with no BR treatment). The effect time of BR treatment was two and four weeks. Results showed that BR significantly improved the yield and morpho-physiological characteristics of all legume crops in this study. The improvement of the morpho-physiological characteristics was attributed to the morphological and physiological parameters, where the increase in plant height, seedling fresh mass, seedling dry mass, root fresh mass, and root dry mass were ascribed to morphological parameters; photosynthetic and chlorophyll content parameters were ascribed to physiological parameters. Interestingly, the foliar application method was significantly (P = 0.05) better than the control in all parameters. Thus, the results confirmed that foliar BR has the potential to improve plant growth in general. [ABSTRACT FROM AUTHOR]

Vitamins play an essential role in broiler nutrition. They are fundamental for normal metabolic and physiological process, and their requirements for poultry are not fixed and can be affected by multiple factors. In contrast, mycotoxins are a challenging issue because they hinder performance and the immune system. Vitamin supplementation above minimum requirements would permit improvement in productive potential, health, bone and meat quality in a situation of mycotoxin challenge. The objective of this study was to determine the influence of optimum vitamin nutrition in diets contaminated with aflatoxin in broilers from 1 to 44 days of age. A total of 1800 Cobb 500 male chicks were randomized to 15 sets of eight treatment groups, each containing 15 birds using a 2 × 2 × 2 factorial design (commercial vitamin levels and high vitamin levels, two levels of aflatoxin – 0 and 0.5 ppm with binder levels of 0 and 10 000 mg/kg). The mash diets were corn and soybean meal based, formulated according to commercial practices. Feed intake, weight gain and feed conversion were analyzed for birds from 1 to 44 days of age. To determine carcass characteristics (carcass yield, breast yield and leg yield) and black bone syndrome, two birds were slaughtered from each group at 45 days. Other analyses included breast tenderness, water loss by dripping and malonaldehyde concentrations. The results demonstrated that broilers that were fed high levels of vitamins showed better weight gain, feed conversion, carcass yield and breast yield than broilers that were fed diets with commercial vitamin levels (P < 0.05); also, broilers that were fed diets containing 0.5 ppm aflatoxin had lower weight gain, carcass yield and breast yield (P < 0.05). The use of 10 000 mg/kg of binder improved (P < 0.05) feed conversion throughout the rearing period. We conclude that aflatoxin negatively affects performance and carcass yield; however, feeding optimum vitamin nutrition improved these performance traits. [ABSTRACT FROM AUTHOR]

Pine wilt disease (PWD), caused by the pine wood nematode (PWN) Bursaphelenchus xylophilus, leads to serious losses to pine forestry around the world. Pinus massoniana, which is vulnerable to be attacked by the PWN, is the dominant species used in pine forestry in China. The objective of this study is to develop a direct PCR-based method for detecting B. xylophilus in the wood of P. massoniana without a separate nematode extraction step. A simple procedure was first developed for isolating B. xylophilus DNA in 5 mg pine wood tissue samples harbouring PWN for detection by PCR amplification. A B. xylophilus-specific amplicon of 403 bp (DQ855275) was generated by PCR from the infested wood tissue. The entire procedure can be completed within 5 h with one pair of primers. This assay can serve as a rapid, cheap and environmentally friendly method to detect B. xylophilus in samples of P. massoniana. [ABSTRACT FROM AUTHOR]

To track malaria parasites for biological studies within the mosquito and mammalian hosts, we constructed a stably transformed clonal line of Plasmodium berghei, PbFluspo, in which sporogonic and pre-erythrocytic liver-stage parasites are autonomously fluorescent. A cassette containing the structural gene for the FACS-adapted green fluorescent protein mutant 2 (GFPmut2), expressed from the 5' and 3' flanking sequences of the circumsporozoite (CS) protein gene, was integrated and expressed at the endogenous CS locus. Recombinant parasites, which bear a wild-type copy of CS, generated highly fluorescent oocysts and sporozoites that invaded mosquito salivary glands and were transmitted normally to rodent hosts. The parasites infected cultured hepatocytes in vitro, where they developed into fluorescent pre-erythrocytic forms. Mammalian cells infected by these parasites can be separated from non-infected cells by fluorescence activated cell sorter (FACS) analysis. These fluorescent insect and mammalian stages of P. berghei should be useful for phenotypic studies in their respective hosts, as well as for identification of new genes expressed in these parasite stages.

In regions where malaria is endemic, inhabitants remain susceptible to repeated reinfection as they develop and maintain clinical immunity. This immunity includes responses to surface-exposed antigens on Plasmodium sp.-infected erythrocytes. Some of these parasite-encoded antigens may be diverse and phenotypically variable, and the ability to respond to this diversity and variability is an important component of acquired immunity. Characterizing the relative specificities of antibody responses during the acquisition of immunity and in hyperimmune individuals is thus an important adjunct to vaccine research. This is logistically difficult to do in the field but is relatively easily carried out in animal models. Infections in inbred mice with rodent malaria parasite Plasmodium chabaudi chabaudi AS represent a good model for Plasmodium falciparum in humans. This model has been used in the present study in a comparative analysis of cross-reactive and specific immune responses in rodent malaria. CBA/Ca mice were rendered hyperimmune to P. chabaudi chabaudi (AS or CB lines) or Plasmodium berghei (KSP-11 line) by repeated infection with homologous parasites. Serum from P. chabaudi chabaudi AS hyperimmune mice reacted with antigens released from disrupted P. chabaudi chabaudi AS-infected erythrocytes, but P. chabaudi chabaudi CB and P. berghei KSP-11 hyperimmune serum also contained cross-reactive antibodies to these antigens. However, antibody activity directed against antigens exposed at the surfaces of intact P. chabaudi chabaudi-infected erythrocytes was mainly parasite species specific and, to a lesser extent, parasite line specific. Importantly, this response included opsonizing antibodies, which bound to infected erythrocytes, leading to their phagocytosis and destruction by macrophages. The results are discussed in the context of the role that antibodies to both variable and invariant antigens may play in protective immunity in the face of continuous susceptibility to reinfection.

Intracellular bacteria and parasites typically invade host cells through the formation of an internalization vacuole around the invading pathogen. Plasmodium sporozoites, the infective stage of the malaria parasite transmitted by mosquitoes, have an alternative mechanism to enter cells. We observed breaching of the plasma membrane of the host cell followed by rapid repair. This mode of entry did not result in the formation of a vacuole around the sporozoite, and was followed by exit of the parasite from the host cell. Sporozoites traversed the cytosol of several cells before invading a hepatocyte by formation of a parasitophorous vacuole, in which they developed into the next infective stage. Sporozoite migration through several cells in the mammalian host appears to be essential for the completion of the life cycle.

Detailed morphological comparisons with light and scanning electron microscopy were made of white females and cysts of several isolates of Globodera tabacum sspp. tabacum (GTT), virginiae (GTV), and solanacearum (GTS). Observations focused on body shape, anterior region including head shape, lip pattern, stylet morphology, and the terminal area in females; and body shape and terminal area of cysts. The most useful characters to separate the three subspecies were forms of the female body, cyst, stylet knobs, tail region, perineal tubercles, anal-fenestral ridge patterns, and the distinctiveness of the anus. GTT is characterized by having round females and cysts, sharply back sloped stylet knobs, clumped perineal tubercles in the vulval region, tight parallel ridges in the cyst anal-fenestral region, and a uniformly conoid tail region. GTV is characterized by its ovoid to ellipsoid female and cyst shape, the "Dutch shoe" shape of the dorsal stylet knob, the more dispersed perineal tubercles, a maze-like pattern of ridges in the anal-fenestral region, and an indistinct anus. GTS is characterized by its ovoid to ellipsoid female and cyst shape, moderately backward sloped stylet knobs, more widely separated ridges, a distinct anus, and a usually crescent shaped tail region. Much variability in shape and patterns is visible among all the isolates of the different subspecies. Tubercles in the neck, as well as bullae, are reported, and their taxonomic value is discussed.

A morphometric evaluation of second-stage juveniles (J2), males, females, cysts, and eggs of several isolates of the tobacco cyst nematode (TCN) complex, Globodera tabacum tabacum (GTT), G. t. virginiae (GTV), and G. t. solanacearum (GTS) is presented. Morphometrics of eggs, J2, and males are considerably less variable than of females and cysts. No measurements of eggs and J2 are useful for identification of the three subspecies. Distance from the median bulb and excretory pore to the head end in J2 and males is quite stable. Stylet knob width of males is useful for identifying GTV isolates and tail length in separating males of GTT isolates from GTV and GTS. Body length/width (L/W) ratio of females and cysts discriminates GTT from GTV and GTS; stylet knob width is an auxiliary character for identifying GTV. This subspecies complex has a continuum of values for the other characters. Data suggest a close relationship between GTV and GTS, which also occur in close proximity in Virginia.

Morphological comparisons with light microscopy and scanning electron microscopy were made among second-stage juveniles (J2) and males of several isolates of the three subspecies of the tobacco cyst nematode complex, Globodera tabacum sspp. tabacum, virginiae, and solanacearum. Observations focused on the anterior region, (including head shape, lip pattern, and stylet morphology) and the tail region (including tail shape in J2 and spicules in males). The three subspecies could not be separated on the basis of any of these characters.