Impact of sub-lethal residues of azinphos-methyl on the pheromone-communication systems of insecticide-susceptible and insecticide-resistant obliquebanded leafrollers Choristoneura rosaceana (Lepidoptera: Tortricidae)

The effects of sub-lethal residues of azinphos-methyl on pheromone production, calling, female attractiveness and the ability of males to locate sources of natural and synthetic pheromone were compared in azinphos-methyl-susceptible (susceptible) and azinphos-methyl-resistant (resistant) obliquebanded leafrollers, Choristoneura rosaceana (Harris). The amount of pheromone in susceptible females was reduced by 29-33% after exposure to azinphos-methyl; this treatment did not affect the pheromone content of resistant females. Azinphos-methyl-treated resistant females contained 39-43% less pheromone than azinphos-methyl-treated susceptible females. Resistant females that were not treated with azinphos-methyl contained 35-56% less pheromone than susceptible females that were not treated with insecticide. The incidence of calling was reduced by 67-100% in azinphos-methyl-treated susceptible females; the incidence of calling by resistant females was not affected by exposure to azinphos-methyl. The incidence of calling by azinphos-methyl-treated susceptible females was 58-100% lower than that of azinphos-methyl-treated resistant females. There was no difference in the incidence of calling between susceptible and resistant females that had not been treated with insecticide. In a flight tunnel, treatment with insecticide reduced the attractiveness of susceptible females by 38%; treatment with insecticide did not affect the attractiveness of resistant females. There was no difference in the proportion of males attracted to susceptible and resistant females that had, or had not been treated with insecticide. In an apple orchard, the attractiveness of susceptible and resistant females treated with azinphos-methyl was reduced by 84 and 12%, respectively. The proportion of males attracted to azinphos-methyl-treated susceptible females was 58% lower than the proportion attracted to azinphos-methyl-treated resistant females, whereas, if females were not treated with insecticide, the proportion attracted to resistant females was 57% lower than the proportion attracted to susceptible females. In a flight tunnel, azinphos-methyl did not affect the ability of susceptible or resistant males to locate a source of pheromone gland extract. Likewise, in an apple orchard, the insecticide treatment had no effect on the ability of susceptible or resistant males to locate a source of synthetic pheromone. In a flight tunnel, there was no difference in the proportion of azinphos-methyl-treated susceptible and resistant males locating a source of pheromone gland extract; however, in the orchard, 39% fewer azinphos-methyl-treated resistant males located a source of synthetic pheromone than azinphos-methyl-treated susceptible males. A similar proportion of susceptible and resistant males that had not been treated with insecticide located a source of pheromone gland extract in the flight tunnel, but in the orchard, the proportion of resistant males not treated with azinphos-methyl that located the source of synthetic pheromone was 32% lower than the proportion of susceptible males not treated with this insecticide. The implications of the differences in the effect of sub-lethal residues of azinphos-methyl on the pheromone communication system of susceptible and resistant moths are discussed in relation to the theory of the development of insecticide resistance, the detection of resistance in feral populations of moths using sex pheromone-baited traps, and the control of moths using sex pheromone-mediated mating disruption.     

Spineless cactus (Opuntia ficus-indica) and saltbush (Atriplex halimus L.) as feed supplements for fattening Awassi male lambs: effect on digestibility,water consumption,blood metabolites,and growth performance

The effect of replacing 13.6% and 20.3% of a total ration of fattening Awassi lambs by two combinations of fresh saltbush (Atriplex halimus) and fresh spineless cactus (Opuntia ficus-indica) cladodes at a ratio of 1.9:1 (TRT1) and 1.7:1 (TRT2) on water intake, digestibility, blood metabolites, and fattening performance was evaluated. Thirty-six lambs with average initial live weight 34.5?±?4.18 kg were randomly assigned to three diets (control, TRT1, and TRT2). The control received a diet containing 166 g/kg barley straw and 834 g/kg of commercial concentrate mixture; TRT1 comprised 126 g barley straw, 739 g/kg concentrate mixture, 47 g/kg spineless cactus, and 89 g saltbush; TRT2 comprised 67 g/kg barley straw, 704 g/kg commercial concentrate mixture, 86 g/kg spineless cactus, and 144 g saltbush. A growth trial of 100 days (10 days of adaptation and 90 days of collection) followed by a metabolism trial of 17 days (10 days of adaptation and 7 days of a total feces and urine collection) was carried out. Daily dry matter intake, digestibility of crude protein, ether extract and nutrient detergent fiber, nitrogen balance, average daily gain, feed conversion ratio, and blood metabolites were not significantly affected by the treatment. Water consumption in TRT2 was significantly 16% less compared with the control. A combination of saltbush and spineless cactus at a ratio of 1.7:1 (TRT2) replaced 60% of barley straw and 16% of concentrate mixture without adverse effects on health and growth performance of Awassi male lambs. This represents a potential reduction in feed costs for smallholder farmers.

     

Comparison of efficiency of in vitro cloned sheep embryo production by conventional somatic cell nuclear transfer and handmade cloning technique

Conventional somatic cell nuclear transfer (SCNT) technique of in vitro production of cloned embryos involves use of costly and complicated micromanipulators. Handmade cloning (HMC) technique has been applied as efficient and cost‐effective alternative in many livestock species. The aim of the present study was to compare the efficiency of in vitro production and in vitro development of cloned sheep embryos by the two techniques. Cloned embryos were produced by conventional SCNT using micromanipulator apparatus and by HMC technique. Enucleation efficiency and efficiency of fusion with somatic cell (nucleus donor) were compared. Cleavage percentage was observed on day 2 of in vitro culture (IVC), and morula and blastocyst percentages were calculated on day 7 of IVC. Higher enucleation efficiency (96.98 ± 1.01 vs. 93.62 ± 1.03; p > .05) as well as fusion efficiency was obtained with HMC technique than with conventional SCNT (96.26 ± 1.34 vs. 92.63 ± 0.70, p < .05); 181 cloned sheep embryos were produced in vitro by conventional SCNT and 92 by HMC. Cleavage percentage observed on day 2 of in vitro culture was higher in HMC than SCNT (66.92 ± 3.72 vs. 55.97 ± 2.5, respectively, p < .05). Morula percentage obtained was higher in SCNT than HMC (44.12 ± 2.93 vs. 30.43 ± 6.79, respectively, p < .05), whereas blastocyst percentage obtained by HMC was higher (12.46 ± 4.96) than SCNT (5.31 ± 2.25; p > .05). It was inferred that HMC technique provides a cost‐effective and efficient method of in vitro production of cloned sheep embryos with a comparatively simpler technique with a possibility of automation. Efficiency of cloned embryo production could be improved further by propagating and standardizing this technique.     

Rangeland Livestock Production in Relation to Climate and Vegetation Trends in New Mexico

A large statewide historical database involving livestock numbers, vegetation cover, precipitation, air temperature, and drought frequency and severity allowed us to explore relationships between climate and rangeland livestock grazing levels and livestock productivity from 1920 to 2017. Trends in vegetation cover and livestock grazing levels from 1984 to 2017 were also explored. Our climate time series was divided into two periods, 1920 ? 1975 and 1976 ? 2017, based on an apparent accelerated increase in mean annual air temperatures that began in the mid-1970s. Both mean annual precipitation (MAP) and mean annual air temperature (MAT) differed (P ≤ 0.05) between the two periods. MAP and MAT were 9.6% and 3.4% higher in period 2 compared with period 1, respectively. From the 1920s to 2010s the livestock grazing level and weaned calf numbers fell 30% and 40%, respectively, despite a significant increase in MAP. Long-term declines in livestock grazing levels and in weaned calf numbers were significantly (P ≤ 0.05) correlated with increasing MAT (r = ? 0.34 and r = ? 0.43, respectively). No long-term trends (1984–2017) in woody or perennial herbaceous cover were detected at the level of the entire state of New Mexico. Woody plant cover dynamics for New Mexico were not related to livestock grazing levels. However, at the county level we detected a 2% increase in woody plant cover coupled with a 9% decrease in cattle animal units between 2000 and 2002 and 2015 and 2017 for 19 select counties well distributed across New Mexico. Increases in woody plant cover varied greatly among counties and were higher for eastern than western New Mexico. Both global and New Mexico data show the climate warming trend is accelerating. Our findings have relevance to several other parts of the world because New Mexico occurs at midlatitude, has varied topography and climatic conditions, and several different range vegetation types.     

Development of single-dispenser pheromone suppression of Epiphyas postvittana, Planotortrix octo and Ctenopseustis obliquana in New Zealand stone fruit orchards

BACKGROUND: Pheromones of two native leafrollers of economic importance to the New Zealand horticulture industry, Planotortrix octo [(Z)‐8‐tetradecenyl acetate and tetradecyl acetate] and Ctenopseustis obliquana [(Z)‐5‐tetradecenyl acetate and (Z)‐8‐tetradecenyl acetate], were reinvestigated and combined with pheromone of Epiphyas postvittana [light‐brown apple moth, (E)‐11‐tetradecenyl actetate and (E, E)‐9,11‐tetradecen‐1‐yl acetate] to develop a single dispenser for mating disruption of three pest species for integrated pest management. RESULTS: Additional compounds identified from pheromone gland extracts were characterised as repellents for P. octo. However, for C. obliquana from Central Otago, a change in ratio of (Z)‐5‐tetradecenyl acetate and (Z)‐8‐tetradecenyl acetate and the addition of three compounds found in the gland (dodecyl acetate, tetradecyl acetate and hexadecanal) led to a significant improvement in catch over previous lures. Males from Central Otago showed antennal electrophysiological responses to hexadecanal, unlike C. obliquana from Auckland, which did not. Three multiple‐species disruption blends were devised in a single dispenser to target E. postvittana, P. octo and C. obliquana. Disruption of traps was recorded in single‐tree replicates with all three blends, but the five‐component blend was overall most effective at disruption and was deployed area wide in commercial orchard plots. CONCLUSIONS: Deployment of single dispensers into commercial stone fruit orchards led to disruption of trapping for the three species and measurable reductions in insecticide use in cherries, peaches and nectarines without increased fruit damage (assessed in apricots). Copyright © 2011 Society of Chemical Industry     

Relationship Between Ion Accumulation and Growth in Two Spring Wheat Lines Differing in Salt Tolerance at Different Growth Stages

A salt-tolerant line, S24, of spring wheat was compared with a salt-sensitive line, Yecora Rojo, in sand cultures at four different growth stages, i.e. germination, seedling, tillering and booting, under greenhouse conditions. The NaCl treatments used were 0 or 125 mol m⁻³ in full strength Hoagland's nutrient solution. S24 exceeded Yecora Rojo in biomass or grain yield at the tillering and booting stages, but these lines did not differ at the initial growth stages, i.e. germination and seedling. The growth performance of the two lines at different growth stages was positively related to the pattern of accumulation of cations and anions. The superiority of S24 to Yecora Rojo at the two later growth stages was related to its relatively low accumulation of Na⁺ or Cl⁻ and high accumulation of K⁺ in leaves. The former line also maintained higher leaf K/Na ratios, Ca/Na ratios, K versus Na selectivities and Ca versus Na selectivities than the latter particularly at the tillering and booting stages. Salt tolerance in spring wheat, in this study, is found to be age-dependent. The booting stage has been found as one of the most appropriate growth stages where maximum differentiation in salt-tolerant and salt-sensitive lines occurred. As is evident from previous studies with spring wheat, in the present study there is a positive correlation between partial exclusion of Na⁺ or Cl⁻¹ from the tissues and maintenance of high tissue K/Na and Ca/Na ratios, and K versus Na and Ca versus Na selectivities, and salt tolerance of this crop.     

Evaluation of state and community/private forests in Punjab,Pakistan using geospatial data and related techniques

Background: Forests are fundamental in maintaining water supplies, providing economic goods, mitigating climate change, and maintaining biodiversity, thus providing many of the world’s poorest with income, food and medicine.Too often, forested lands are treated as "wastelands" or "free" and are easily cleared for agricultural and infrastructure expansion.Methods: In this paper, the sustainability of two forest ecosystems(state and community/private owned) was evaluated using SPOT-5 satellite images of 2005 and 2011. This study was conducted in a sub-watershed area covering 468 km2, of which 201 km2 is managed by the state and 267 km2 by community/private ownership in the Murree Galliat region of Punjab Province of Pakistan. A participatory approach was adopted for the delineation and demarcation of forest boundaries. The Geographic Object-Based Image Analysis(GEOBIA) technique was used for identification and mapping of ten Land Cover(LC) features.Results: The results show that between the years 2005 to 2011, a total of 55 km2(24 km2 in state-owned forest and 31km2 in community/private forest) was converted from forest to non-forest. The conclusion is that conservation is more effective in state-owned forests than in the community/private forests.Conclusions: These findings may help to mobilize community awareness and identify effective initiatives for improved management of community/private forest land for other regions of Pakistan.     

Intra-specific Variation for Salt Tolerance in Linseed (Linum usitatissimum L.)

Thirty-six accessions of linseed ( Linum usitatissimum L.) were screened for salt tolerance at the seedling stage after 2 weeks growth in solution culture salinized with 150mol m⁻³ NaCL Considerable variation in salt tolerance was observed in this set of germplasm. Two salt-tolerant accessions, T-5(69-S9)B and LS-2 and two salt-sensitive accessions P-70 and Aver-Rer-Seic, selected at the seedling stage, were grown to maturity in sand culture salinized with 0 (control), 70, 140, and 210 mol m⁻³ NaCl. Both the salt-tolerant accessions exceeded the two salt-sensitive accessions in biomass production, seed yield, and yield components, but the accessions did not differ significantly in seed oil content in the salt treatments. The tolerant accessions accumulated greater amounts of Na⁺ in the shoots and less in the roots compared with the salt-sensitive accessions. The shoot K⁺, K: Na ratios, and K⁺ versus Na⁺ selectivity were lower in the salt-tolerant accessions compared with the salt-sensitive accessions; the reverse was true for their roots. Contributions of Na⁺ and Ca²⁺ to osmotic adjustment were much higher in the two salt-tolerant accessions than in the salt-sensitive ones.
It has been established that there is a great deal of variation for salt tolerance in linseed. The degree of salt tolerance of this crop does not vary during ontogeny. The physiological basis of salt tolerance of this species appears to be associated with the inclusion of Na⁺ in the shoots.     

Inoculating wheat seedlings with exopolysaccharide-producing bacteria restricts sodium uptake and stimulates plant growth under salt stress

A pot experiment was conducted to elucidate the effects of inoculating five exopolysaccharide- (EPS-) producing bacterial strains on the dry matter yield and the uptake of K⁺, Na⁺, and Ca²⁺ by wheat seedlings grown in a moderately saline soil. The bacteria were isolated from the rhizosphere soil (RS) of wheat grown in a salt-affected soil and included Aeromonas hydrophila/caviae (strain MAS-765), Bacillus insolitus (strain MAS17), and Bacillus sp. (strains MAS617, MAS620 and MAS820). The inoculation substantially increased the dry matter yield of roots (149–527% increase) and shoots (85–281% increase), and the mass of RS (176–790% increase). All the strains, except MAS617, also increased the RS mass/root mass ratio as well as the population density of EPS bacteria on the rhizoplane, and both these parameters were significantly correlated with the content of water-insoluble saccharides in the RS. Inoculation restricted Na⁺ uptake by roots, which was not attributable to the binding of Na⁺ by the RS, or to the ameliorative effects of Ca²⁺ under salinity. The decreased Na⁺ uptake by roots of inoculated than uninoculated plants was probably caused by a reduced passive (apoplasmic) flow of Na⁺ into the stele due to the higher proportion of the root zones covered with soil sheaths in inoculated treatments. Among the strains tested, MAS820 was the most efficient in all respects, whereas MAS617 was the least effective. Results suggested that inoculating selected EPS-producing bacteria could serve as a useful tool for alleviating salinity stress in salt-sensitive plants.