Influence of chemical and biological treatments on volatile oil composition of Artemisia annua Linn.

The relative abundance of isoprenoids and other volatile components in the aerial parts of Artemisia annua Linn. (Asteraceae) after different nutritional treatments was analyzed by GC and GC/MS. Hydro-distillation of untreated (control) plants yielded 0.28 ± 0.04% essential oil on fresh weight basis. Monoterpenes were predominant in the essential oil of which cis-limonene-1,2-epoxide (22.1%), artemisia ketone (11.5%), iso-pinocamphone (11.4%), thujyl alcohol (9.9%) and camphor (8.4%) were the major components. The essential oil distilled from A. annua treated with Azospirillum (2 ml/plant) amounted to 0.30 ± 0.03% of fresh weight and consisted mainly of neral (31.1%), β-caryophyllene (25.1%), artemisia ketone (10.0%), thujyl alcohol (9.4%), trans-bergamotene (8.5%) and spathulenol (4.8%). The essential oil from plants treated with basal N, P, K and S application (in the form of urea P₂O₅, K₂O and gypsum at a rate of 120, 50, 100 and 50 kg/ha, respectively) amounted to 0.32 ± 0.03% of fresh weight and consisted mainly of thujyl alcohol (33.3%), β-caryophyllene (15.5%), cis-undec-5-ene (14.4%), artemisia ketone (6.0%), trans-nerolidol (5.8%) and undec-4-ene (4.6%). The hydrodistillation of A. annua treated with Glomus (Mycorrhizal soil 50 g/plant) yielded 0.50 ± 0.02% essential oil on fresh weight basis. The sesquiterpenes were predominant in this essential oil and consisted of β-caryophyllene (51.2%), trans-bergamotene (15.4%), α-gurjunene (14.3%), germacrene D (5.1%) and ledol (4.5%) as major components. The only monoterpenes in the essential oil were neral, nerol and pulegone (each less than 1%). These findings suggest that A. annua treated with Glomus lacks glandular trichomes—the primary sites of synthesis of monoterpenes.     

Pattern of genetic inheritance of morphological and agronomic traits of sorghum associated with resistance to sorghum shoot fly, <Emphasis Type="Italic">Atherigona soccata</Emphasis>

Sorghum shoot fly, Atherigona soccata is an important pest of sorghum during the seedling stage, which influences both fodder and grain yield. To understand the nature of inheritance of shoot fly resistance in sorghum, we performed generation mean analysis using two crosses IS 18551 × Swarna and M 35-1 × ICSV 700 during the 2013–2014 cropping seasons. The F₁, F₂, BC₁ and BC₂ progenies, along with the parental lines were evaluated for agronomic and morphological traits associated with resistance/susceptibility to sorghum shoot fly, A. soccata. The cross IS 18551 × Swarna exhibited significant differences between the parents for shoot fly deadhearts (%) in the postrainy season. The progenies of this cross exhibited lower shoot fly damage, suggesting that at least one of the parents should have genes for resistance to develop shoot fly-resistant hybrids. Leaf glossiness, leafsheath pigmentation and plant vigor score during the seedling stage exhibited non-allelic gene interactions with dominant gene action, whereas 100 seed weight showed both additive and dominant gene interactions. Presence of awns showed recessive nature of the awned gene. Generation mean analysis suggested that both additive and dominance gene effects were important for most of the traits evaluated in this study, but dominance had a more pronounced effect.     

Groundwater Purification in a Polymetallic Mining Area (SW Sinai,Egypt) Using Functionalized Magnetic Chitosan Particles

A magnetic glycine-grafted chitosan sorbent (Gly) was functionalized to produce a hydrazide derivative (HGly). The two sorbents were tested in batch mode for the sorption of a series of 10 metal ions present in the groundwater collected in three wells in the Wadi (valley) Nasib mining area (SW Sinai, Egypt). HGly is much more efficient for metal recovery than Gly. Under selected experimental conditions (sorbent dosage 1.5 g L^?1), the sorption efficiency is not sufficient for achieving the standard levels for drinking water: the most problematic metal ions in terms of drinkability remain aluminum (too high metal concentration in the groundwater), cadmium, and chromium for the three wells (and nickel in the case of only one well). Increasing the sorbent dosage improves the treatment efficiency. The sorbent (HGly) was tested in fixed-bed columns. The breakthrough curves were compared for the different metals for the groundwater collected in the most contaminated of the three wells. The levels of metal concentration in the treated groundwater are too high for direct use in irrigation. However, they are consistent with the standards for livestock drinking water (based on FAO recommendations, Food and Agriculture Organization of the United Nations). The metals can be readily desorbed using 0.5 M HCl solutions with a relatively high concentrating effect (i.e., 50 times). The re-use of the sorbent for three successive cycles of sorption/desorption cycles shows a progressive but weak decrease in sorption and desorption performances.     

Effect of Nitrogen Application Timing on Yield Components,Fodder, Grain,and Oil Yields of Brassica Cultivars

The dual-purpose use of Brassica cultivars means cutting or grazing the crop as fodder and then letting it to re-grow and produce grain with little or no yield penalty. A field experiment was conducted in randomized complete block design with split plot arrangement with three replications. Three Brassica cultivars, three nitrogen application timing, and cutting treatments were included in the experiment. The findings indicated that Brassica cultivar Abasin-95 produced higher fresh and dry fodder yields, seeds pod^?1, seed, biological, and oil yields. However, NIFA Raya resulted in a higher number of pods and branches plant^?1. Likewise, fresh and dry fodder yields were higher with nitrogen (N) application all at sowing. Nitrogen applied in two splits resulted in a higher number of pods plant^?1 and grain yield. Cutting suppressed all parameters except 1000 grain weight. Uncut plots produced significantly higher branches plant^?1, pods plant^?1, seeds pod^?1, seed, biological, and oil yields than cut plots.     

Two new lathyrane type diterpenoids from Euphorbia aellenii

Euphorbia aellenii Rech. f. (Euphorbiaceae) afforded a cytotoxic chloroform fraction from which two new esters of 6(17)-epoxylathyrol were identified (1 and 2). The structure of these compounds was elucidated by spectroscopic methods.     

Evaluation of cognitive loads imposed by traditional paper-based and innovative computer-based instructional strategies

Strategies of presenting instructional information affect the type of cognitive load imposed on the learner's working memory. Effective instruction reduces extraneous (ineffective) cognitive load and promotes germane (effective) cognitive load. Eighty first-year students from two veterinary schools completed a two-section questionnaire that evaluated their perspectives on the educational value of a computer-based instructional program. They compared the difference between cognitive loads imposed by paper-based and computer-based instructional strategies used to teach the anatomy of the canine skeleton. Section I included 17 closed-ended items, rated on a five-point Likert scale, that assessed the use of graphics, content, and the learning process. Section II included a nine-point mental effort rating scale to measure the level of difficulty of instruction; students were asked to indicate the amount of mental effort invested in the learning task using both paper-based and computer-based presentation formats. The closed-ended data were expressed as means and standard deviations. A paired t test with an alpha level of 0.05 was used to determine the overall mean difference between the two presentation formats. Students positively evaluated their experience with the computer-based instructional program with a mean score of 4.69 (SD=0.53) for use of graphics, 4.70 (SD=0.56) for instructional content, and 4.45 (SD=0.67) for the learning process. The mean difference of mental effort (1.50) between the two presentation formats was significant, t=8.26, p≤.0001, df=76, for two-tailed distribution. Consistent with cognitive load theory, innovative computer-based instructional strategies decrease extraneous cognitive load compared with traditional paper-based instructional strategies.     

Survey of ixodid ticks in domestic ruminants in Bedelle district,Southwestern Ethiopia

A survey aimed at determining the status of ticks in cattle, sheep and goats in Bedelle district (Southwestern Ethiopia) was carried out from November 2007 to April 2008. Out of the total 330 animals examined, 314 (95.2%) were found to be infested (harbouring of at least a single tick). High rates of infestations were recorded across all three host species. Factors like month of collection, age and sex of host species did not show significant association with infestation rates. A total of 5,507 ticks belonging to three genera (i.e. Amblyomma, Boophilus and Rhipicephalus) were collected during the study period of which six species were identified. The species of ticks encountered comprise of Amblyomma cohaerens (44.1%), Amblyomma variegatum (13.8%), Amblyomma lepidum (1.2%), Boophilus decoloratus (24.9%), Rhipicephalus evertsi evertsi (14.3%) and Rhipicephalus lunulatus (1.7%). As about 86.7% (4,772) of the ticks were collected from cattle, it was recognised that this could be an evidence of host preference where cattle are serving as principal host while sheep and goats serve as alternative hosts. The role of ecological factors and little attention paid by livestock owners for treatment of animals against ticks are suggested to result in the abundance of ticks. Acaricide spraying should be strategically applied to control ticks. Better result could be achieved if an emphasis is being put on spraying cattle. Studies on tick-borne diseases, involvement of wildlife species as well as related factors are recommended as they may provide a valuable basis for designing and launching an all-round control programme in the country.     

Effects of Bermudagrass hay and soybean hulls inclusion on performance of sheep fed cactus-based diets

The objective of this experiment was to determine the effects of replacing corn with soybean hulls (SH) or Bermudagrass tifton hay (TH) on performance of sheep fed cactus-based diets. Three ruminally fistulated sheep were used in a 3 × 3 Latin square experiment with 21-day periods. All diets contained 75% spineless cactus (dry matter basis, DM) and formulated to be isonitrogenous. Fiber source had no influence on nutrient intakes except for the intake of neutral detergent fiber (NDF) which was lower (p < 0.05) for animals fed corn relative to those fed SH or TH. Time expended in rumination and total chewing time were higher (p < 0.05) for animals fed TH than those fed SH or corn. In vivo nutrient digestibilities were similar for all dietary treatments and averaged 69.6%, 74.8%, 69.9%, and 61.8% for DM, organic matter, crude protein, and NDF, respectively. Feeding SH relative to TH and corn decreased ruminal pH (p < 0.05) and increased concentration of total volatile fatty acids (p < 0.05). However, ruminal NH₃–N concentration was higher (p < 0.05) for animal fed TH than for those fed SH or corn. Abdominal distension and ruminal biofilm production were greater (p < 0.05) in animals fed corn or SH than in those fed TH. It was concluded that replacing corn with SH or TH up to 15% of the diet DM in a cactus-based diet had no effect on nutrient intakes or total tract nutrient utilization. Changes in ruminal fermentation parameters reflected differences in ruminal degradability between the two fiber sources. Bermudagrass tifton hay was more effective than SH in reducing the risk of bloat associated with feeding high levels of spineless cactus to ruminants.     

Defoliation and nitrogen effects on photosynthesis and growth of Eucalyptus globulus

Plant responses to defoliation are complex. We established a field experiment in a nine-month-old Eucalyptus globulus Labill. plantation to examine the effects of pattern (upper crown versus lower crown removal), frequency (single, double or triple defoliation within a 12-month period) and severity (25 versus 38% of leaf area removed) of defoliation and the effect of soil nitrogen (N) on photosynthetic processes and stem growth. The photosynthetic responses observed following defoliation could be attributed to changes in source:sink ratios. Light-saturated CO(2) uptake (A(max)) increased with increasing severity and frequency of defoliation irrespective of defoliation pattern. Seedlings defoliated in autumn did not exhibit increases in A(max) until the following spring, whereas there was no such delay in photosynthetic responses associated with spring defoliation. Application of N before defoliation allowed trees to compensate for the effect of defoliation on stem diameter growth, which could not be explained simply in terms of increases in A(max). The observed increases in stem diameter increment following N fertilization of defoliated trees suggested increases in leaf area development, and there were changes in the leaf area:leaf dry mass ratio that may have increased light absorption by the crown. Nitrogen fertilization also increased partitioning of dry mass to branches at the expense of main stems, suggesting that N supply was important in rebuilding crowns following a defoliation event.