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PubMed1967

Break-down of the molluscicide N-tritylmorpholine in soil and in rice.

The molluscicide N-tritylmorpholine (Frescon, WL 8008) is likely to be applied to flowing water systems in bilharziasis control programmes. The treated water in irrigation systems will sometimes be applied to growing crops, such as rice, and the nature of the terminal residues of N-tritylmorpholine in rice has therefore been investigated.Crops were grown under greenhouse conditions in soil treated with water containing (14)C-and(3)H-N-tritylmorpholine, using dosage levels very much greater than those that will generally be used in the field. The major radiocomponent in the rice plants was triphenylcarbinol (triphenylmethanol), together with smaller amounts of unchanged N-tritylmorpholine and o-, m-, and p-hydroxytriphenylcarbinol. The hydroxytriphenylcarbinols were present as the free hydroxy compounds and as plant conjugates.Residues of the parent molluscicide and its break-down products are not considered likely to present a toxic hazard to animals or men that eat the crops.

Molluscacides↗
PubMed2005

Ascosphaera aggregata contamination on alfalfa leafcutting bees in a loose cell incubation system.

The alfalfa leafcutting bee, a solitary bee used to pollinate alfalfa seed crops, is seriously affected by chalkbrood, a larval disease caused by the fungus Ascosphaera aggregata. One attempt to control the disease includes removing nests from the nesting boards (the "loose cell" system). We report here that adults emerging from the loose cells are heavily contaminated with A. aggregata spores. The contamination levels are not as high as previously reported for bees emerging directly from the boards, but they are still a likely focus for disease spread and may need to be targeted in chalkbrood control strategies.

Animals↗
PubMed1995

Phosalone poisoning on the cation-linked ATPases of central nervous system of Rana tigrina (Daudin).

An acute dose of phosalone, an organophosphate pesticide, widely used in crop fields, injected to Rana tigrina, intraperitoneally, inhibited the different inorganic ion linked ATPase enzymes of the central nervous system (CNS). Six discrete CNS compartments, namely telencephalon, mid-brain, rhombencephalon, cervical spinal cord, thoracic spinal cord and lumbar spinal cord showed markedly diminished ATPase activity. ATPases inhibition affected the neuronal activity and muscular coordination leading to moribund or comatose phase in the poisoned frogs. The specific inhibition of Mg(2+)-ATPase suggests the uncoupling action of the compound in the neuronal tissue. Increased oxygen uptake in the brain regions of phosalone-treated frogs also supports the above uncoupling action.

Animals↗
PubMed1996

Dynamic control of photosynthetic photon flux for lettuce production in CELSS.

A new dynamic control of photosynthetic photon flux (PPF) was tested using lettuce canopies growing in the Minitron II plant-growth/canopy gas-exchange system. Canopy photosynthetic rates (Pn) were measured in real time and fedback for further environment control. Pn can be manipulated by changing PPF, which is a good environmental parameter for dynamic control of crop production in a Controlled Ecological Life-Support Systems CELSS. Decision making that combines empirical mathematical models with rule sets developed from recent experimental data was tested. With comparable yield indices and potential for energy savings, dynamic control strategies will contribute greatly to the sustainability of space-deployed CELSS.

Biomass↗
PubMed2004

The reuse of treated wastewater for agricultural purposes in Nicaragua; Central America.

The first subsurface flow wetland (SSFW) system for about 1,000 PE, was constructed in Nicaragua in 1996 to apply this technology in the form of an integral project, combining the treatment of domestic wastewater with its reuse for crop production in small and medium size communities. The SSFW-effluent meets all standards established in the national regulations for wastewater reuse in agriculture, except for faecal coliforms, existent at an average concentration of 7 x 10(4) MPN/100 ml. A conventional surface irrigation method was used to irrigate different crop species selected to establish their risk of contamination. To judge the potential health risk for consumers and farmers, samples of vegetables and fruits harvested in the dry seasons of the years 1997 to 2002, were analyzed for the presence of pathogenic microorganisms like faecal coliforms, salmonella and shigella. In addition, a yield comparison between crops irrigated with well water using chemical fertilizers, and crops irrigated with the effluent of the SSFW-system was made, to analyze the economical benefits of the wastewater reuse.

Agriculture↗
PubMed2006

Detection and resolution of genetic loci affecting circadian period in Brassica oleracea.

Circadian rhythms regulate many aspects of plant growth, fitness and vigour. The components and detailed mechanism of circadian regulation to date have been dissected in the reference species Arabidopsis thaliana. To determine the genetic basis and range of natural allelic variation for intrinsic circadian period in the closest crop relatives, we used an accurate and high throughput data capture system to record rhythmic cotyledon movement in two immortal segregating populations of Brassica oleracea, derived from parent lines representing different crop types. Periods varied between 24.4 and 26.1 h between the parent lines, with transgressive segregation between extreme recombinant lines in both populations of approximately 3.5 h. The additive effect of individual QTL identified in each population varied from 0.17 to 0.36 h. QTL detected in one doubled haploid population were verified and the mapping intervals further resolved by determining circadian period in genomic substitution lines derived from the parental lines. Comparative genomic analysis based on collinearity between Brassica and Arabidopsis also allowed identification of candidate orthologous genes known to regulate period in Arabidopsis, that may account for the additive circadian effects of specific QTL. The distinct QTL positions detected in the two populations, and the extent of transgressive segregation suggest that there is likely to be considerable scope for modulating the range of available circadian periods in natural populations and crop species of Brassica. This may provide adaptive advantage for optimising growth and development in different latitudes, seasons or climate conditions.

Brassica↗
PubMed2001

Population dynamics of Pythium aphanidermatum in cucumber grown in closed systems.

Foot and root rot in cucumber, caused by Pythium aphanidermatum (Edson) Fitzp., is an economically important disease in soilless culture systems. Nevertheless, very few data are available on the populations of this pathogen. Therefore, two detection methods, nested PCR (polymerase chain reaction) and plating on a selective medium after concentration of samples, were optimised and evaluated. With both methods very low concentrations of P. aphanidermatum could be detected; i.e. the detection limits were around 0.05 CFU/ml nutrient solution. In addition, real-time quantitative PCR using a Molecular Beacon probe was designed and tested. The potential and limitations of the different detection methods are discussed. With these different detection techniques, the population dynamics of P. aphanidermatum in a cucumber crop was followed. The impact of different disinfection treatments was studied in a greenhouse experiment with a cucumber crop growing on rockwool slabs in 12 independent closed systems. The nutrient solution was recirculated without disinfection (control), after UV-irradiation (250 mJ/cm2), or after slow sand filtration treatment. Part of the crop was inoculated with an isolate of P. aphanidermatum. The non-inoculated part could only become infected through the recirculated nutrient solution. Disease symptoms (stem rot, wilt, and root rot) and the yield loss were recorded in addition to the population dynamics of the pathogen. Very clear differences in the spread of the pathogen and in disease symptoms were measured between the systems with and without disinfection. UV-irradiation and slow sand filtration were both effective in removing the pathogen and protected the crop from disease symptoms. Correlation indices between the final yield and the different measurements during the experiment were calculated.

Colony Count, Microbial↗
PubMed2001

Determination of dithiocarbamate fungicide residues in food by a spectrophotometric method using a vertical disulfide reaction system.

Dithiocarbamates are a class of fungicides extensively used in many crops worldwide. The current residue definition of dithiocarbamates in food for compliance with maximum residue limits, at national and international levels, is total residues arising from the use of any or each dithiocarbamate fungicide, determined as CS(2). The analytical method most frequently used to analyze dithiocarbamate residues in food for monitoring purposes was proposed more than 30 years ago. In this method, total dithiocarbamates are decomposed to CS(2), which is purified and reacted with a cupric reagent. The yellow complex formed is quantified by spectrophotometry. In this paper, a new reaction system for the purification and complexation of CS(2) is proposed. The new system is less fragile than the traditional design, is easier to assemble, and allows for a higher sample throughput, in addition to being of low cost. Recovery of added mancozeb, thiram, or ziram (0.15-8.0 mg/kg) in rice, beans, apple, banana, orange, papaya, tomato, cucumber, and potato ranged from 82 to 120%, with relative standard deviations from 0 to 10% (n = 3 or 5). Analysis of apple, tomato, and papaya samples with field-incurred dithiocarbamate residues showed comparable results using both the traditional and the new reaction systems.

Disulfides↗
PubMed2026

Artificial intelligence-driven advancements in agricultural biotechnology.

The need for faster and more informative data processing for better decision-making is driving the adoption of artificial intelligence (AI) in the agricultural sector. Thanks to recent advancements in computer science and the increase in computational powers of modern computers, AI is not only augmenting traditional solutions, but also helping in developing novel solutions to existing challenging matters. AI-driven models have an exceptional ability to identify patterns and combine a diverse collection of data together and make inference. The increasing pressure on farmlands posed by the growing global population and climate change is lessening growth, yield, and productivity ultimately posing risk to food security worldwide. Incorporation of AI in agriculture has the potential to drive farming efficiency to new heights. This comprehensive review critically evaluates the evolution of AI in agricultural biotechnology from a theoretical concept to a global phenomenon. A comprehensive literature search was performed using major scientific databases, including PubMed, Web of Science, Embase, Scopus, Lens and the Cochrane Library. In this review, we empirically demonstrate the fields advancement toward more capable AI systems and discuss the current applications of AI across crop improvement and precision agriculture such as crop improvement and genetic engineering, genomic selection and plant breeding, pest and disease detection, precision agriculture and smart farming, soil health and nutrient management, climate resilient crop development, livestock biotechnology, challenges and ethical considerations in AI based agricultural biotechnology. Furthermore, this review addresses the exponential growth of commercial intellectual property in the field and contrast it with academic publication outputs. Finally, we critically assess the ethical challenges impeding equitable adoption of AI including data sovereignty and digital divide, while projecting future frontiers involving quantum computing. This review will help build sustainable agricultural systems capable of adapting to climate change, contribute to the development of climate-resilient and high-yielding crops, and address global food security challenges.

Agriculture↗
PubMed2005

Simulation supported scenario analysis for water resources planning: a case study in northern Italy.

The work presents the results of a comprehensive modelling study of surface and groundwater resources in the Muzza-Bassa Lodigiana irrigation district, in Northern Italy. It assesses the impact of changes in land use and irrigation water availability on the distribution of crop water consumption in space and time, as well as on the groundwater resources. A distributed, integrated surface water-groundwater simulation system was implemented and applied to the study area. The system is based on the coupling of a conceptual vadose zone model with the groundwater model MODFLOW. To assess the impact of land use and irrigation water availability on water deficit for crops as well as on groundwater system in the area, a number of management scenarios were identified and compared with a base scenario, reflecting the present conditions. Changes in land use may alter significantly both total crop water requirement and aquifer recharge. Water supply is sufficient to meet demand under present conditions and, from the crop water use viewpoint, a reduction of water availability has a positive effect on the overall irrigation system efficiency; however, evapotranspiration deficit increases, concentrated in July and August, when it may be critical for maize crops.

Agriculture↗
PubMed2004

Principles of biorefineries.

Sustainable economic growth requires safe, sustainable resources for industrial production. For the future re-arrangement of a substantial economy to biological raw materials, completely new approaches in research and development, production and economy are necessary. Biorefineries combine the necessary technologies between biological raw materials and industrial intermediates and final products. The principal goal in the development of biorefineries is defined by the following: (biomass) feedstock-mix + process-mix --> product-mix. Here, particularly the combination between biotechnological and chemical conversion of substances will play an important role. Currently the "whole-crop biorefinery", "green biorefinery" and "lignocellulose-feedstock biorefinery" systems are favored in research and development.

Bioelectric Energy Sources↗
PubMed2006

A multisite telemammography system for remote management of screening mammography: an assessment of technical, operational, and clinical issues.

OBJECTIVE: This paper describes a high-quality, multisite telemammography system to enable "almost real-time" remote patient management while the patient remains in the clinic. One goal is to reduce the number of women who would physically need to return to the clinic for additional imaging procedures (termed "recall") to supplement "routine" imaging of screening mammography. MATERIALS AND METHODS: Mammography films from current and prior (when available) examinations are digitized at three remote sites and transmitted along with other pertinent information across low-level communication systems to the central site. Images are automatically cropped, wavelet compressed, and encrypted prior to transmission to the central site. At the central site, radiologists review and rate examinations on a high-resolution workstation that displays the images, computer-assisted detection results, and the technologist's communication. Intersite communication is provided instantly via a messaging "chat" window. RESULTS: The technologists recommended additional procedures at 2.7 times the actual clinical recall rate for the same cases. Using the telemammography system during a series of "off-line" clinically simulated studies, radiologists recommended additional procedures at 1.3 times the actual clinical recall rate. Percent agreement and kappa between the study and actual clinical interpretations were 66.1% and 0.315, respectively. For every physical recall potentially avoided using the telemammography system, approximately one presumed "unnecessary" imaging procedure was recommended. CONCLUSION: Remote patient management can reduce the number of women recalled by as much as 50% without performing an unreasonable number of presumed "unnecessary" procedures.

Ambulatory Care Facilities↗
PubMedDate not supplied

Photoperiod shift effects on yield characteristics of rice.

Edible yield must be maximized for each crop species selected for inclusion in the Controlled Ecological Life-Support System (CELSS) proposed by NASA to support long-term manned space missions. In a greenhouse study aimed at increasing biomass partitioning to rice (Oryza sativa L.) grain, plants of the high yielding semi-dwarf rice cultivar Ai-Nan-Tsao were started in pots under 8-h photoperiods at a density of 212 plants m-2. After different periods of time under 8-h photoperiods, pots were switched to continuous light for the remainder of the cropping cycle. Continuous light did not delay time to first panicle emergence (60 d) or time to harvest (83 d). There was a positive correlation between the length of continuous light treatments and nongrain biomass. Grain yield (1.6 +/- 0.2 g plant-1) did not increase in continuous light. Yield-efficiency rate (grain weight per length of cropping cycle, canopy volume, and weight of nongrain shoot biomass) was used to compare treatments. Small Ai-Nan-Tsao rice canopies grown under 8-h photoperiods were more efficient producers of grain than canopies grown under continuous light for a portion of the rice cropping cycle.

Biomass↗
PubMed2005

An evaluation of production and economic efficiency of two beef systems from calving to slaughter.

A 3-yr experiment was conducted with cows and their calves to evaluate resource inputs, animal performance, and carcass characteristics of two production systems. In the control system, cows (CON; n = 99/yr) grazed pasture and were fed hay during the winter, and CON steer calves were finished in the feedlot for 211 d after weaning. In the treatment system (TRT; n = 100/yr), cows grazed pasture and crop residue during the winter and were fed hay. Treatment steer calves grazed crop residue after weaning, grazed pasture in the spring and summer, and were finished in the feedlot for 90 d. Body condition scores after TRT cows returned from crop residue grazing were greater (P < 0.01) for CON than for TRT cows. Calving rates were similar for both groups (CON = 91%; TRT = 93%). In the feedlot, CON steers had lower (P < 0.05) ADG and DMI, but were more efficient (P < 0.01) than TRT steers. Treatment steers had greater (P < 0.05) final weight, hot carcass weight and longissimus muscle area, and decreased marbling score. The cost per weaned calf and weaning breakeven were greater (P = 0.07) for the CON system than for the TRT system (CON = 455.12 dollars, 0.91 dollar/0.45 kg; TRT = 421.43 dollars, 0.84 dollar/0.45 kg). When steers were priced into the postweaning phase on an economic basis, slaughter breakeven was lower (P = 0.01), and profit potential tended (P = 0.14) to be greater for TRT steers when they were sold on a live basis. When steers were priced into the postweaning phase on a financial basis, slaughter breakeven was lower (P = 0.03) and profit potential from the sale of steers on a live basis was greater (P = 0.07) for TRT than for CON steers. Economic evaluation of the total system resulted in greater (P = 0.06) profit potential for the TRT system when steers were priced into the system on either an economic or a financial basis and when steers were sold on a live basis, but no differences were observed when steers were sold on a grid basis. Despite differences in cow weight and body condition, calving rates did not differ between systems. Although calves were herdmates, feedlot performance and carcass characteristics differed between systems. The TRT system had lower weaning and slaughter breakeven, lower cost per weaned calf, and greater profit potential when finished steers were sold on a live basis.

Animal Feed↗
PubMed1996

A Framework to Assess Regional Environmental Impacts of Dedicated Energy Crop Production

Numerous studies have evaluated air quality and greenhouse gas mitigation benefits of biomass energy systems, but the potential environmental impacts associated with large-scale changes in land-use patterns needed to produce energy crops have not been quantified. This paper presents a framework to assess the potential soil, water, and biodiversity impacts that may result from the large-scale production of dedicated energy crops. The framework incorporates producer economic decision models with environmental models to assess changes in land use patterns and to quantify the consequent environmental impacts. Economic and policy issues that will affect decisions to produce energy crops are discussed. The framework is used to evaluate erosion and chemical runoff in two Tennessee regions. The analysis shows that production of dedicated energy crops in place of conventional crops will significantly reduce erosion and chemical runoff.

Journal Article↗
PubMed2000

A geographic information assessment of birth weight and crop production patterns around mother's residence.

A landscape approach using remote sensing (RS) and geographic information system (GIS) technologies was developed to identify the proximity of maternal residence to agricultural areas, and the association between crop production patterns around mothers residences and low birth weight was evaluated. Satellite data obtained for Weld County, Colorado, in 1991 and 1993 were digitally processed to generate crop location maps for this study. GIS procedures were then used to determine crop types within 300- and 500-m circular zones around mothers' homes for 125 births that occurred from 1991 to 1993 in the study area. The relationships between different crop patterns around the mothers' residences and the birth weight of babies were investigated while controlling for potential confounding variables. The results indicated that low birth weight was associated with total crop production area within a 300-m buffer zone around mothers' residences (P=0.058). When each of the study crops was considered separately, low birth weight was associated with sugar beet production (P=0.05) and corn production (P=0.1) within both the 300- and the 500-m buffer zones. This RS/GIS approach provides clues to the potential relationships between birth weight and crop production near the residence.

Adult↗
PubMed1995

The food-process subsystem for CELSS: a conceptual analysis.

A controlled ecological life support system (CELSS) is required to sustain life for future long-duration space missions. Food processing is an important subsystem component of a CELSS. Factors for designing the food-process subsystem are identified and characterized in this analysis. Interactions of the subsystem with other subsystems in a CELSS are also discussed.

Crops, Agricultural↗
PubMedDate not supplied

Production and energetic use of biogas from energy crops and wastes in Germany.

The production of biogas for reducing fossil CO2 emissions is one of the key strategic issues of the German government and has resulted in the development of new process techniques and new technologies for the energetic use of biogas. Progress has been made in cultivating energy crops for biogas production, in using new reactor systems for anaerobic digestion, and in applying more efficient technologies for combined heat and power production. Recently, integration of fuel cells within the anaerobic digestion process was started, and new technologies for biogas upgrading and conversion to hydrogen were tested. This article describes the trends in Germany for achieving more efficient energy production.

Bacteria, Anaerobic↗