The coastal zone is a big place: some 40% of the world’s population lives within 100 km of the sea and this zone is under increasing pressure. Sustainable development and management of coastal zone resources are vitally important to human well-being, to national economies and to the ecosystems on which we depend. In simple spatial terms, the coastal zone is the interface between the lan…
Industrial tree crops contribute substantially to the economy of many developing countries on the Asian, African, and Latin American continents. With the World Trade Organization (WTO) substantially focusing on agriculture, the commercial aspects of growing these crops assume considerable economic significance. Within the developing world, there are countries whose sole economic sustenance …
In a relatively brief period the soybean has become a major crop plant in the United States. Based on the utilization of the bean, or products therefrom, a substantial soybean industry has also developed. Its uses, agricultural and industrial, primarily depend on the high content of both protein (ca. 40%) and oil (ca. 20%) in the bean. Soybeans are a cash crop and provide a significant par…
As a consequence of the success of post-World War II agriculture, particularly in western Europe, many in affluent societies have taken food for granted for decades. We lack historical perspective to conclude that the gap between the world demand and supply of food is widening or otherwise. Nonetheless, the recent debate on this gap and the role of research and development in agriculture is a…
In the vast areas of tropical and subtropical regions there is a category of widely distributed, highly weathered soils known as "Red Earths," also referred to as Ferralsols, Acrisols, Oxisols, Ultisols, Latosols, Lateritic Soils, Krasnozems, Ferrisols, and Ferrallitic Soils. Because of the abundant rainfall and high temperature, this type of soil is considered one of the most important agricul…
The dry lands with which this work is concerned, are the areas of meagre or undependable rainfall, in which the average precipitation is deficient in relation to water requirements. These include the arid zones, in which arable crop production is not possible without irrigation, and also their semi-arid fringes, in which rainfall, though precarious, is sufficient for certain types of crops, req…
Tilletia ehrhartae, a smut fungus infecting perennial veldtgrass Ehrharta calycina, is epitypified and characterized using the Consolidated Species Concept, including morphology, ecology (host plant) and rDNA sequences (ITS and LSU). Tilletia ehrhartae is native and endemic to the Cape Floral Kingdom (located entirely in South Africa), but it has also been introduced to the alien artificial ran…
Plant-parasitic nematodes are extremely destructive pathogens with a cosmopolitan distribution and a host range that affects most crops. They are characterized by distinct parasitic lifestyles, e.g., as sedentary or migratory endo- or ectoparasites, resulting in high losses in yield and revenue. Possessing limited lipid metabolism, they produce one or two structurally unique classes of small �…
Fusarium corm rot is the major destructive disease of Crocus sativus, a perennial herb whose stigma forms the commercially important spice Bsaffron^. In the present study we isolated a native Bacillus strain with antagonistic activity against a Fusarium oxysporum isolate causing the disease. Three fungi, Fusarium oxysporum, F. solani and Penicillium sp., were isolated from the corms showing cla…
Banana bunchy top disease is caused by the Banana bunchy top virus (BBTV), which is a species of the genus Babuvirus in the family Nanoviridae. In this study, we collected 61 isolates of BBTV from Sumatra Island. The sequences of DNA-R and DNA-S of 61 samples and DNA-U3 of 37 samples were determined. Although the Sumatra population has different sequences in the stem-loop region in DNA-U3, it i…
A standard area diagram (SAD) set to aid assessment of bacterial spot (caused by Xanthomonas spp.) severity on tomato (Solanum lycopersicum L.) leaves was prepared and evaluated for improving accuracy, precision and reliability of visual estimates. The proposed SAD set contains illustrations of leaves with 12 distinct disease severity values from 0.5 to 90 %, and was validated by 12 raters with…
Three hundred and fifty six isolates of Rhizoctonia solani were obtained from potato stems and tubers in the main potato growing regions of China between 2011 and 2014. On the basis of the hyphal anastomosis and sequence analysis of the internal transcribed spacers of the ribosomal DNA, 249 isolates (69.94 %) were identified to anastomosis group (AG)-3 PT, 44 (12.36 %) to AG-5, 39 (10.96 %) to …
Reactive oxygen species (ROS) can be promoted differently, although iron is regarded as a condicio sine qua of their generation. We assessed how enzymes involved in ROS production and iron accumulation impact the interactions between Pinus sylvestris root and pathogens with di fferent host preferences (Heterobasidion annosum sensu stricto, H. parviporum and H. abietinum). Studies with inhibitor…
The potyvirus-induced passion fruit woodiness disease (PWD) is considered the most important limiting factor for passion fruit production in several countries. In Brazil, PWD is caused by the Cowpea aphid-borne mosaic virus (CABMV), and to date there are no reports on the existence of P. edulis genotypes resistant to this virus. Thus, resistance gene introgression from wild Passiflora species f…
We have investigated the uptake and delivery of Erwinia amylovora-specific bacteriophages in apple plants. The main aim of this study was to assess the potential of phage application as a means for improving phage persistence and thereby the control of fire blight, the disease caused by E. amylovora. Both phage strains tested (ΦEa104 and H5K) were able to translocate in apple seedlings and we…
Sclerotinia sclerotiorum is a filamentous fungal phytopathogen capable of infecting many economically important crops and vegetables. The dinitroaniline fungicide fluazinam had not been registered for control of S. sclerotiorum in China until April 2014. In this study, control efficacy of fluazinam was determined and baseline sensitivity of S. sclerotiorum to this fungicide was established base…
The adjusted stochastic weather generator to disaggregate the monthly climate averages into daily timescale is investigated due to the limitations of Climate Models in representing the daily weather fluctuations. We use weather generator for daily precipitation and maximum and minimum temperature are investigated for Sao Paulo State. We use the adjusted stochastic weather generator to disaggreg…
The water salinization is a widespread phenomenon in the world and generally, it is accompanied by salinization of soils. This makes very hard to grow any crops because to irrigate with salt water often destroys crops and fertility of soils. To mitigate such issues, within a geographical area of Sicily involved in such problems and declared at risk of desertification, Giuseppe Ingiaimo applied…
Field studies were conducted in Wyoming and Nebraska in 2007 through 2009 to evaluate winter wheat response to aminocyclopyrachlor. Aminocyclopyrachlor was applied at rates between 15 and 120 g ai ha-1 6, 4, and 2 mo before winter wheat planting (MBP). Redroot pigweed control was 90% with aminocyclopyrachlor rates of 111 and 50 g ha-1 when applied 4 or 2 MBP. Aminocyclopyrachlor at 37 g ha-1 co…
The inclusion of winter cereals in spring-annual rotations in the northern Great Plains may reduce weed populations and herbicide requirements. A broad range of spring and winter cereals were compared for ability to suppress weeds and maximize grain yield at Lacombe (2002 to 2005) and Lethbridge (2003 to 2005), Alberta, Canada. High seeding rates (≥ 400 seeds/m2) were used in all years to max…
† Background and Aims: The morphological variability of the flower in angiosperms, combined with its relatively simple structure, makes it an excellent model to study cell specification and the establishment of morphogenetic patterns. Flowers are the products of floral meristems, which are determinate structures that generate four different types of floral organs before terminating. The prec…
In the rice–wheat (RW) systems of the Indo-Gangetic Plains of South Asia, conservation tillage practices, including zerotillage (ZT), are being promoted to address emerging problems such as (1) shortages of labor and water, (2) declining factor productivity, (3) deterioration of soil health, and (4) climate change. Despite multiple benefits of ZT, weed control remains a major challenge to ado…
Organic agricultural systems increase the complexity of weed management, leading organic farmers to cite weeds as one of the greatest barriers to organic production. Integrated Weed Management (IWM) systems have been developed to address the ecological implications of weeds and weed management in cropping systems, but adoption is minimal. Organic agriculture offers a favorable context for a…
In northern U.S. vegetable cropping systems, attempts at no-till (NT) production have generally failed because of poor crop establishment and delayed cropmaturity. Strip tillage (ST) minimizes these problems by targeting tillage to the zone where crops are planted whilemaintaining untilled zones between crop rows, which foster improvements in soil quality. ST has been shown to maintain crop yie…
Desiccation following prolonged air exposure challenges survival of aquatic plants during droughts, water drawdowns, and overland dispersal. To improve predictions of plant response to air exposure, we observed the viability of vegetative fragments of 10 aquatic plant species (Cabomba caroliniana, Ceratophyllum demersum, Elodea canadensis, Egeria densa, Myriophyllum aquaticum, Myriophyllum he…
Reduced-tillage systems including no-tillage and striptillage have well-known benefits for conserving and improving soils, protecting vulnerable crops from extreme weather events, and reducing labor and fuel costs associated with full-width inversion tillage. Despite these benefits, reduced-tillage has not been widely adopted in many cropping systems due in part to the increased difficulty of m…
The widespread evolution of multiple herbicide resistance in the most serious annual weeds infesting Australian cropping fields has forced the development of alternative, non-chemical weed control strategies, especially new techniques at grain harvest. Harvest weed seed control (HWSC) systems target weed seed during commercial grain harvest operations and act to minimize fresh seed inputs to th…
Saflufenacil (KixorTM) is a new protoporphyrinogen IX oxidase (PPO) inhibiting herbicide for preplant burndown and selective PRE dicot weed control in multiple crops, including corn. The biokinetic properties and the mechanism of selectivity of saflufenacil in corn, black nightshade, and tall morningglory were investigated. After root treatment of plants at the third-leaf stage, the difference …
Herbicides are the foundation of weed control in commercial crop-production systems. However, herbicide-resistant (HR) weed populations are evolving rapidly as a natural response to selection pressure imposed by modern agricultural management activities. Mitigating the evolution of herbicide resistance depends on reducing selection through diversification of weed control techniques, minimizing …
In little over 20 yr, Palmer amaranth has risen from relative obscurity to its current status as one of the most widespread, troublesome, and economically damaging agronomic weeds in the southeastern U.S. Numerous factors have enabled Palmer amaranth to become such a dominant and difficult-to-control weed, including its rapid growth rate, high fecundity, genetic diversity, ability to tolerate a…
Cover crop–based organic rotational no-till soybean production has attracted attention from farmers, researchers, and other agricultural professionals because of the ability of this new system to enhance soil conservation, reduce labor requirements, and decrease diesel fuel use compared to traditional organic production. This system is based on the use of cereal rye cover crops that are mecha…
The introduction of herbicide-resistant crops and postemergence herbicides with a wide action spectrum shifted the research focus from how to when crops should be treated. To maximize net return of herbicide applications, the evolution of weed–crop competition over time must be considered and its effects quantified. A model for predicting the yield trend in relation to weed removal time, cons…
Natural herbicides approved in organic agriculture are primarily nonselective burn-down essential oils applied POST. Multiple applications are often required due to their low efficacy. To address this problem, the in vivo herbicidal activity of manuka oil, the essential oil distilled from manuka tree (Leptospermum scoparium J.R. and G. Forst), was tested on selected broadleaf and grass weeds. W…
A study was conducted in summer fallow fields near Davenport, WA, and Pendleton, OR, in 2007 and 2008 to evaluate the POST weed control efficacy of herbicide treatments applied with a light-activated, sensor-controlled (LASC) sprayer compared to the broadcast application of glyphosate. The LASC application of glyphosate alone (at all rates) and in mixture with pyrasulfotole plus bromoxynil or 2…
Seed production of annual weeds persisting through cropping phases replenishes/establishes viable seed banks from which these weeds will continue to interfere with crop production. Harvest weed seed control (HWSC) systems are now viewed as an effective means of interrupting this process by targeting mature weed seed, preventing seed bank inputs. However, the efficacy of these systems is dire…
Herbicides are small molecules that inhibit specific molecular target sites within plant biochemical pathways and/or physiological processes. Inhibition of these sites often has catastrophic consequences that are lethal to plants. The affinity of these compounds for their respective target sites makes them useful tools to study and dissect the intricacies of plant biochemical and physiological …
Development of herbicide-resistant crops has resulted in significant changes to agronomic practices, one of which is the adoption of effective, simple, low-risk, crop-production systems with less dependency on tillage and lower energy requirements. Overall, the changes have had a positive environmental effect by reducing soil erosion, the fuel use for tillage, and the number of herbicides with …
Extensive areas in the upper Midwest have been invaded by spotted knapweed, and effective management strategies are required to reestablish native plant communities. We examined effects of mowing, mowing plus clopyralid, or mowing plus glyphosate in factorial combination with hand pulling and burning on knapweed abundances on a knapweed-infested site in western Michigan. We applied mowing and h…
The ecology of tropical bracken, which occurs in tropical regions, is not well known. We studied its response to weather variations and burning in the south Ecuadorian Andes, where this weed had already overgrown 40% of the pastureland. In field observations, a constant 1 : 1 ratio of emerging and dying leaves suggested limitation of frond density by nutrient shortage. Short-term deviations fro…
Herbicides are the primary method used to control exotic, invasive plants. This study evaluated restoration efforts applied to grasslands dominated by an invasive plant, sulfur cinquefoil, 6 yr after treatments. Of the five herbicides we evaluated, picloram continued to provide the best control of sulfur cinquefoil over 6 yr. We found the timing of picloram applications to be important to the n…
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…