Resistance to glufosinate has been confirmed in glyphosate-resistant Italian ryegrass populations collected in hazelnut orchards in Oregon. Dose–response, ammonia accumulation, and enzyme activity studies were conducted to test the sensitivity of three glyphosate-resistant and three susceptible Italian ryegrass populations to glufosinate. The glufosinate rates required to reduce the growth by…
Johnsongrass is one of the most troublesome weeds of the world and is listed as a noxious weed in Arkansas. Reduced johnsongrass control with the recommended application rate of glyphosate (840 g ae ha21) was reported in a continuous soybean field near West Memphis, AR, in the fall of 2007. A greenhouse study was conducted (1) to confirm and characterize glyphosate resistance in the johnsongras…
Re-seeding efforts to restore or rehabilitate Great Basin rangelands invaded by exotic annual grasses are expensive and have generally achieved limited success. There is a need to identify new strategies to improve restoration outcomes. We tested the performance of a native early seral seed mix (annual forbs, early seral grasses and shrubs) with that of a native late seral mix representative of…
The challenges associated with the adoption of conservation tillage and/or low-input cropping systems, whether organic or herbicide-free, across Canada are shaped by scale, environment, and local practices. A study in eastern Canada captured the challenges of introducing low-input cropping systems in mature (20þ yr) tillage treatments in a barley/red clover/corn/soybean rotation. Each mature t…
Auxinic herbicides are widely used for control of broadleaf weeds in cereal crops and turfgrass. These herbicides are structurally similar to the natural plant hormone auxin, and induce several of the same physiological and biochemical responses at low concentrations. After several decades of research to understand the auxin signal transduction pathway, the receptors for auxin binding and resul…
Prairies are imperiled habitats, with remnants being generally small and often existing in isolation. Invasive plants have the potential to invade not just the edge of small remnants but also the interior because smaller remnants experience greater edge effects than do large, contiguous prairies. Additionally, invasive plants limit recruitment of native plants, which can arrest secondary succes…
Noninversion tillage with tine- or disc-based cultivations prior to crop establishment is the most common way of reducing tillage for arable cropping systems with small grain cereals, oilseed rape, and maize in Europe. However, new regulations on pesticide use might hinder further expansion of reduced-tillage systems. European agriculture is asked to become less dependent on pesticides and prom…
Weeds cause crop loss indirectly by reducing the quantity of resources available for growth. Quantifying the effects of weed interference on nitrogen (N) supply, crop growth, and N nutrition may assist in making both N and weed management decisions. Experiments were conducted to quantify the effect of N addition and weed interference on soil nitrate-N (NO3-N) over time and the dependence of cor…
With growing agricultural demands from both conventional and organic systems comes the need for sustainable practices to ensure long-term productivity. Implementation of reduced- or no-till practices offers a number of environmental benefits for agricultural land and maintains adequate yield for current and future production. Concerns over satisfactory pest control options, particularly weed co…
Researchers, product registration personnel, and growers desire the ability to chemically detect residual amounts of herbicides in soil at concentrations below those necessary to cause phytotoxicity to sensitive nontarget or rotational crop plants. Alfalfa, cotton, soybean, and sunflower, crops sensitive to low concentrations of aminocyclopyrachlor in soil, were planted at field test sites appr…
Corallita (Antigonon leptopus) is a perennial vine, lauded as an ornamental for its vigorous growth, and plentiful (usually) pink flowers, and even its ability to smother unsightly landscapes. In the United States it thrives in horticultural zones 8 to 10, and also is successfully grown worldwide in tropical climates. When corallita is neglected, it can grow quickly over other vegetation, sprea…
As cases of resistance to herbicides escalate worldwide, there is increasing demand from growers to test for weed resistance and learn how to manage it. Scientists have developed resistance-testing protocols for numerous herbicides and weed species. Growers need immediate answers and scientists are faced with the daunting task of testing an increasingly large number of samples across a variety …
The United States is charging toward the largest expansion of agriculture in 10,000 years with vast acreages of primarily exotic perennial grasses planted for bioenergy that possess many traits that may confer invasiveness. Cautious integration of these crops into the bioeconomy must be accompanied by development of best management practices and regulation to mitigate the risk of invasion posed…
Beach vitex is a salt-tolerant, perennial, invasive shrub that has naturalized in coastal areas of the southeastern United States. Since its introduction in the 1980s, this Pacific Rim native has invaded many fragile beach-dune ecosystems along the Mid-Atlantic, Southern Atlantic, and Gulf of Mexico. Large-scale monocultures of beach vitex supplant native species through rapid vegetative reprod…
Agroecosystems are inherently complex, and practices aimed at managing one component of the system can have unintended consequences for other components of the system. Management decisions, therefore, can be improved by assessing and understanding the multivariate nature of agricultural systems and the multifunctional character of particular agricultural management practices. The act of simult…
Glyphosate is regularly used to control annual bluegrass populations in dormant bermudagrass turf. A population of annual bluegrass not controlled by glyphosate at 840 g ha-1 (glyphosate resistant, GR) was identified on a golf course in Humboldt, TN in 2010. Mature tillers of GR plants were established in a greenhouse and treated with glyphosate at 0, 210, 420, 840, 1,680, 3,360, and 6,720 g ha…
A waterhemp population from a native-grass seed production field in Nebraska was no longer effectively controlled by 2,4-D. Seed was collected from the site, and dose-response studies were conducted to determine if this population was herbicide resistant. In the greenhouse, plants from the putative resistant and a susceptible waterhemp population were treated with 0, 18, 35, 70, 140, 280, 560, …
This contributed book applies mathematical models and systems analysis techniques to the study of insect pests, plant pathogens, and human diseases. The research programmes of over 40 scientists from aU over the world are compared and contrasted in detail to provide a stateof-the-art review on how such modelling can increase the effectiveness of more traditional ecological, biological, and chem…
Herbicides are one of the most widely used groups of pesticides worldwide for controlling weedy species in agricultural and non-crop settings. Due to the extensive use of herbicides and their value in weed management, herbicide research remains crucial for ensuring continued effective use of herbicides while minimizing detrimental effects to ecosystems. Presently, a wide range of research conti…
As the veg specialist on Which? Gardening, when off ering advice to readers, I found that the hardest question to answer was “I want to grow vegetables; how do I start?” I’ve started three allotments myself over the years, and watched many novices start out enthusiastically but fail to make a go of it. This book would surely have made a diff erence. How many of us set out with good i…
Assessment of contamination of foods with monochloropropanediols (MCPD) and subsequent mitigation of their formation is an important current issue of a global food security. Methods for the determination of 2- or 3-MCPD in foods at low µg/kg levels require analyte derivatization prior to gas chromatographymass spectrometry (GC-MS) determination. All existing methods suffer from various dr…
1 The most important defoliating pest of Sitka spruce Picea sitchensis in the U.K. is the green spruce aphid Elatobium abietinum. This aphid species is expected to respond to a predicted increase in the incidence of spring–summer drought events, with serious implications for growth of infested spruce plants and control of the pest. 2 Growth rate, adult weight and nymph weight of E. abietin…
Agriculture can serve as an important engine for economic growth in developing countries, yet yields in these countries have lagged far behind those in developed countries for decades. One potential mechanism for increasing yields is the use of improved agricultural technologies, such as fertilizers, seeds, and cropping techniques. Public sector programs have attempted to overcome information-r…
During a study of the contribution of photosynthetic traits to biomass yield among 11 diverse species of willow, the light and CO 2 dependence of photosynthesis were found to differ, with absolute rates at ambient and saturating CO 2 , together with maximum rates of Rubsico-limited and electron-transportlimited photosynthesis ( V cmax and J , respectively) varying by factors in excess of 2…
Compared to other potential feedstocks such as sugarcane, sugar beet, maize, and watermelon, sweet sorghum possesses higher levels of directly fermentable reducing sugars within the culm and the ability to accumulate high biomass under low-input production systems. In addition, it is tolerant to drought and has more efficient utilization of solar radiation and nitrogen-based fertilizers than ma…
This study investigated the ability of Neofusicoccum luteum to infect wounded shoots, trunks, pruned cane ends, leaf surfaces, buds, berries and roots, and its further progression into stem tissues. All tissue types were susceptible to infection except roots, with highest incidences in trunks (100%), cane ends (100%), shoots (92%) and buds (88%), indicating that in New Zealand, N. luteum is pri…
1. This study examined biological characteristics of sexual and asexual strains of the parasitoid wasp, Lysiphlebus fabarum (Marshall) (Hymenoptera:Braconidae). 2. Strains were reared in different instar hosts (the black bean aphid, Aphis fabae Scopoli) under identical environmental conditions (21 ∘C, 65–75% RH, and LD 16:8 h). 3. Results showed that the second instar of the aphid is the …
The effect of the dual inoculation with arbuscular mycorrhizal (AM) and saprophytic fungi and a combination of wheat straw and sewage sludge residues were studied by determining their effect on dry weight of tomato and on chemical and biochemical properties of soil. Incubation of organic residue (sewage sludge combined with wheat straw) with saprophytic fungi and plant inoculation with myco…
Recent development of site-specific weed management strategies suggests patch application of herbicides to avoid their excessive use in crops. The estimation of infestation of weeds and control thresholds are important components for taking spray decisions. If weed pressure is below a certain level in some parts of the field and if late germinating weeds do not affect yield, it may not be nece…
To identify crop rotation systems capable of sequestering C and N to 1 metre depth in a subtropical Ferralsol of Southern Brazil managed under long-term zero-tillage (21 yrs), we evaluated six crop sequences: wheat (Triticum aestivum)–soybean (Glycine max) [W-S], the baseline; oat (Avena strigosa, as cover crop)–maize (Zea mays)–wheat–soybean [O-M-W-S]; vetch (Vicia villosa, as legum…
The effect of Citrus tristeza virus (CTV) infection on photosynthetic activity and antioxidant metabolism was analysed in plants of the highly susceptible citrus genotype Mexican lime (Citrus aurantifolia). Two virus isolates differing in their virulence (the severe T318 and the mild T385) were used in the experiments. CTV infection caused a reduction in photosynthetic capacity in infected plan…
Global warming has become one of the major challenges in maintaining global food security. This paper reviews the impacts of climate change on fourteen strategic crops for eight sub- Saharan Africa countries. Climate change is projected to increase median temperature by 1.4–5.5°C and median precipitation by −2% to 20% by the end of the 21st century. However, large levels of uncertaint…
The two field trials evaluated the performance of sesame (var. PBTil) and sunflower (var. Isaanka) intercropped with cassava (var. TMS 30572 and TME 1) in a cassava-based cropping system with a view to studying the phenology of the component crops and establishing mixture productivity in terms of biological efficiency (land equivalent ratio [LER] and area time equivalency ratio [ATER]), in…
There is a broad literature on the impact of Bt cotton adoption in different countries, but few studies have explicitly looked at environmental and health effects from an economic perspective. We analyse the impact of Bt cotton on environmental efficiency in Pakistan, using farm survey data and a doubly heteroskedastic stochastic production function framework. Negative environmental and health…
Water stress is one of the major abiotic stresses that adversely affect cotton production. Seedlings of 142 backcross inbred lines (BILs) derived from Pima cotton ‘Pima S-7’ (Gossypium barbadense L.) 9 Upland cotton ‘Sure-Grow 747’(G. hirsutum L.) were evaluated in two tests for plant height, fresh shoot weight and root weight under two treatments (5% PEG and water-control conditions) …
The sensitivity of photosynthetic metabolism to temperature has been identified as a key uncertainty for projecting the magnitude of the terrestrial feedback on future climate change. While temperature responses of photosynthetic capacities have been comparatively well investigated in temperate species, the responses of tropical tree species remain unexplored. We compared the responses …
As the result of intensive research and breeding efforts over the last 20 years, the yield potential and yield quality of cereals have been greatly improved. Nowadays, yield safety has gained more importance because of the forecasted climatic changes. Drought and high temperature are especially considered as key stress factors with high potential impact on crop yield.Yield safety can only be im…
Introduction – Plants from the Lamiaceae family have been known traditionally for their beneficial health-promoting properties, attributed to their anti-inflammatory, anaesthetic and anti-microbial effects. Objective – The purposes of this study was to characterise the essential oils from four Lamiaceae plants by applying different extraction techniques. Methods – Accelerated solven…
Loss and fragmentation of natural ecosystems are widely recognized as the most important threats to biodiversity conservation, with Neotropical dry forests among the most endangered ecosystems. Area and edge effects are major factors in fragmented landscapes. Here, we examine area and edge effects and their interaction, on ensembles of arthropods associated to native vegetation in a fragmented …
The purpose of this study was to investigate the reproductive cycle of a highelevation population of Aspidoscelis costata costata (1500–1600 m) and compare its reproductive cycle with that of other populations, species, and closely related genera. Adult male A. costata costata lizards were collected, and the reproductive tracts were removed and subjected to histological analyses. Testicular …
This book covers key areas in agricultural science, namely crop improvement, production, response to water, nutrients, and temperature, crop protection, agriculture and human health, and animal nutrition. The contributions by the authors include manipulation of the variables and genetic resources of inheritance of quantitative genes, crop rotation, soil water and nitrogen, and effect of tempera…
The present book is a collection of ten original research articles and reports, associated with selected topics in agricultural chemistry. The discussed issues are organized in four sections: Classification and labeling of active substances in plant protection products, Environmental and stress plant physiology and behavior, Antimicrobial and antioxidant potential of plant extracts, and Polluta…
Background and Aims Specific leaf area (SLA), a key element of the ‘worldwide leaf economics spectrum’, is the preferred ‘soft’ plant trait for assessing soil fertility. SLA is a function of leaf dry matter content (LDMC) and leaf thickness (LT). The first, LDMC, defines leaf construction costs and can be used instead of SLA. However, LT identifies shade at its lowest extreme and succul…
Background and Aims Plants are able to adapt to the environment dynamically through regulation of their growth and development. Excess copper (Cu2+ ), a toxic heavy metal, induces morphological alterations in plant organs; however, the underlying mechanisms are still unclear. With this in mind, the multiple signalling functions of nitric oxide (NO) in plant cells and its possible regulatory r…
Organic farming is an environmental friendly ecosystem management in which, use of all kinds of synthetic inputs are eliminated. The area delineated for" organic farming" forbids use of synthetic fertilizers, pesticides, genetically modified seeds (GMO) and breeds, etc. These are replaced with site-specific management system that maintain and increase long-term soil fertility and prevent …
Large portions of the Great Basin become degraded and disturbed every day due to natural and human-induced causes. Some disturbed areas may recover naturally in time, but other areas may never recover naturally because invasive weeds establish quickly and prevent native plants from establishing. Invasive weeds can potentially spread into adjacent, healthy landscapes where they can threaten loc…
The formation, dispersal, and germination of seeds are crucial stages in the life cycles of gymnosperm and angiosperm plants. The unique properties of seeds, particularly their tolerance to desiccation, their mobility, and their ability to schedule their germination to coincide with times when environmental conditions are favorable to their survival as seedlings, have no doubt contributed s…
Insects are often considered a nuisance to human beings and mere pests for crops and animals. Yet this is far from the truth. Insects provide food at low environmental cost, contribute positively to livelihoods, and play a fundamental role in nature. However, these benefits are largely unknown to the public. Contrary to popular belief, insects are not merely “famine foods” eaten in time…
Background and Aims The herbivore defence system of true grasses (Poaceae) is predominantly based on silicon that is taken up from the soil and deposited in the leaves in the form of abrasive phytoliths. Silicon uptake mechanisms can be both passive and active, with the latter suggesting that there is an energetic cost to silicon uptake. This study assessed the effects of plant-available soil …
Background and Aims The cell cycle-regulated protein ENDOSPERM DEFECTIVE 1 (EDE1) is a novel plant microtubule-associated protein essential for plant cell division and for microtubule organization in endosperm. EDE1 is only present on microtubules at mitosis and its expression is highly cell cycle regulated both at the protein and the transcript levels. Methods To search for EDE1-interacting …