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PubMed1996

NASA's Biomass Production Chamber: a testbed for bioregenerative life support studies.

The Biomass Production Chamber (BPC) located at Kennedy Space Center, FL, USA provides a large (20 m2 area, 113 m3 vol.), closed environment for crop growth tests for NASA's Controlled Ecological Life Support System (CELSS) program. Since the summer of 1988, the chamber has operated on a near-continuous basis (over 1200 days) without any major failures (excluding temporary power losses). During this time, five crops of wheat (64-86 days each), three crops of soybean (90 to 97 days), five crops of lettuce (28-30 days), and four crops of potato (90 to 105 days were grown, producing 481 kg of dry plant biomass, 196 kg edible biomass, 540 kg of oxygen, 94,700 kg of condensed water, and fixing 739 kg of carbon dioxide. Results indicate that total biomass yields were close to expected values for the given light input, but edible biomass yields and harvest indices were slightly lower than expected. Stand photosynthesis, respiration, transpiration, and nutrient uptake rates were monitored throughout growth and development of the different crops, along with the build-up of ethylene and other volatile organic compounds in the atmosphere. Data were also gathered on system hardware maintenance and repair, as well as person-hours required for chamber operation. Future tests will include long-term crop production studies, tests in which nutrients from waste treatment systems will be used to grow new crops, and multi-species tests.

Biomass↗

PubMed2002

Localized versus systemic effect of arbuscular mycorrhizal fungi on defence responses to Phytophthora infection in tomato plants.

Development of biological control for plant diseases is accepted as a durable and environmentally friendly alternative for agrochemicals. Arbuscular mycorrhizal fungi (AMF), which form symbiotic associations with root systems of most agricultural, horticultural and hardwood crop species, have been suggested as widespread potential bioprotective agents. In the present study the ability of two AMF (Glomus mosseae and Glomus intraradices) to induce local or systemic resistance to Phytophthora parasitica in tomato roots have been compared using a split root experimental system. Glomus mosseae was effective in reducing disease symptoms produced by P. parasitica infection, and evidence points to a combination of local and systemic mechanisms being responsible for this bioprotector effect. The biochemical analysis of different plant defence-related enzymes showed a local induction of mycorrhiza-related new isoforms of the hydrolytic enzymes chitinase, chitosanase and beta-1,3-glucanase, as well as superoxide dismutase, an enzyme which is involved in cell protection against oxidative stress. Systemic alterations of the activity of some of the constitutive isoforms were also observed in non-mycorrhizal roots of mycorrhizal plants. Studies on the lytic activity against Phytophthora cell wall of root protein extracts also corroborated a systemic effect of mycorrhizal symbiosis on tomato resistance to Phytophthora.

Chitinases↗

PubMed1990

Comparison of two cattle production systems in Pabna district Bangladesh.

In Pabna district, Bangladesh there are two cattle production systems: a draught-oriented system with local Deshi cattle and more milk-oriented production with Pabna Milking Cow (PMC) stock. Deshi animals are smaller than PMC animals. More PMC cows are milked than Deshi cows and the milk off-take of PMC cows is much higher. The calving interval in Deshi cows is one year longer than in PMC cows. The great majority of the bullocks and the bulls are used as draught animals. More than 80% of the Deshi cows also have to work compared with only about half of the PMC cows. The milk off-take of cows used for draught work is 30% less than that of other cows. One of the major differences between the two systems is that PMC cows have access to grazing along the rivers. These areas are increasingly taken up for cropping and the traditional Pabna milk production farming system is gradually being replaced.

Animal Husbandry↗

PubMed2005

Black-bellied whistling duck (Dendrocygna autumnalis) brain cholinesterase characterization and diagnosis of anticholinesterase pesticide exposure in wild populations from Mexico.

Rice is the main crop in the subbasin of the fluvial lagoon system of Palizada River (FLSPR) in the state of Campeche, Mexico. The pesticides used to control pests of this crop mainly are carbofuran, chlorpyrifos, and glyphosate. Black-bellied whistling duck (Dendrocygna autumnalis) is an ecologically and economically important species in the area. This duck is consumed by local inhabitants throughout the year, despite its potential exposure to pesticides. Due to its feeding habits, abundance, and nutritional value, D. autumnalis is a good indicator of environmental contamination and a potential route of human exposure to organophosphate and carbamate pesticides. In this study, the brain cholinesterase (ChE) in the frontal cerebral cortex of autochthonous ducks was characterized. In addition, the potential of the three locally used pesticides and mixtures to inhibit ChE activity was investigated and the exposure of the wild duck population during intensive pesticide applications in rice fields was evaluated. We found that acetylcholinesterase (AChE) seems to be the predominant ChE form in the biological fraction analyzed. Carbofuran was the most potent ChE inhibitor of D. autumnalis brain ChE activity from the three pesticides analyzed. Cholinesterase inhibition after exposure to pesticide mixtures predominantly was due to carbofuran. A decrease (p < 0.05) in AChE activity (>30%) was apparent in wild ducks compared to reference ducks, with recovery of ChE inhibition in wild ducks occurring months later when no pesticides were applied in the field. Dendrocygna autumnalis brain ChE is a suitable parameter for inclusion in biomonitoring programs for both environmental protection and human safety.

Acetylcholinesterase↗

PubMed2002

Hybrid seed production and the challenge of propagating male-sterile plants.

The introduction of hybrid crop varieties has enabled spectacular increases in productivity owing to hybrid vigor and increased uniformity. To produce hybrid seeds, a pollination control system is required to prevent unwanted self-pollination. In crop species with hermaphrodite flowers, this can be a major challenge. Over the past decade, new pollination control systems have been developed with the aid of genetic engineering, mainly based on the generation of nuclear-encoded male sterility. The successful application of these systems for large-scale hybrid seed production depends on whether the male-sterile female parent line can be multiplied efficiently and economically. In spite of its relevance, the propagation of the male-sterile line has often been overlooked in the development of pollination control systems.

Crops, Agricultural↗

PubMedDate not supplied

The influence of native gut microflora on the colonization and infection of Salmonella gallinarum in chickens.

A native intestinal microflora of chickens that is protective against paratyphoid salmonellae appeared to be partially protective against Salmonella gallinarum and abbreviated the excretion time of S. gallinarum in White Leghorn chicks. Treated birds had a lower incidence of systemic infection measured by liver and spleen culture, and fewer birds developed infection in the intestinal tract. Most of the chickens positive by cloacal swabs excreted S. gallinarum throughout the test period. The low level of protection provided by competitive exclusion suggested that the practice would not prove useful in the practical control of fowl typhoid.

Animals↗

PubMed1975

Status of the digestive system and tibiae of cropectomized hens at night.

Experiments were conducted to determine the effect of cropectomy on the total amount and calcium content of ingesta in the digestive tract of the laying hen at night, as well as to determine if any abnormal physiological changes had occurred in the cropectomized hens. Treatments were cropectomized, sham operated and unoperated control hens. The gizzards from cropectomized hens contained about twice as much feed at 7:30 p.m. as that of the controls. The gizzard weight, without contents, was also significantly heavier in cropectomized hens than that of the controls. At 7:30 p.m. total contents of the digestive system of cropectomized and control hens were 15.94 gm. versus 24.07 gm., respectively. The control birds also had 2.71 times more total calcium in the digestive system at 7:30 p.m. than the cropectomized birds. The contents of the small intestine of cropectomized birds had 17% more calcium at 7:30 p.m. than did that of the controls. However, by 5:30 a.m. the contents of the small intestine of the control birds had 3.17 times more calcium than did that of the cropectomized birds. No differences were found between treatments or between time periods in relation to tibia breaking strength, calcium content of tibia or percent tibia ash. The degree of dietary calcium deficiency at night appears to be greater with cropectomized hens, even though the gizzard compensates, in part, for the loss in storage capacity of the crop. It is hypothesized from these data that the crop is an important and necessary organ in the laying hen for supplying nutrients throughout the night when the hen is not consuming feed.

Animal Feed↗

PubMed1994

Approaches to resource recovery in Controlled Ecological Life Support Systems.

Recovery of resources from waste streams in a space habitat is essential to minimize the resupply burden and achieve self sufficiency. The ultimate goal of a Controlled Ecological Life Support System (CELSS) is to achieve the greatest practical level of mass recycle and provide self sufficiency and safety for humans. Several mission scenarios leading to the ultimate application could employ CELSS component technologies or subsystems with initial emphasis on recycle of the largest mass components of the waste stream. Candidate physical/chemical and biological processes for resource recovery from liquid and solid waste streams are discussed and the current fundamental recovery potentials are estimated.

Biomass↗

PubMed2005

[Simulating net primary production of rice and wheat crops: model establishment].

On the basis of the principles of plant physiology, agro-meteorology and soil environment, net primary production of rice and wheat crops was modeled. The model includes two main functional modules: photosynthesis and respiration, and nitrogen transport within soil-plant system. The processes of photosynthesis and respiration are driven by environmental variables and plant nitrogen content. The transportation of nitrogen within soil-plant system is determined by simulating the processes of crop nitrogen uptake, soil nitrogen mineralization and synthetic nitrogen release.

Biomass↗

PubMed2004

Response of graywater recycling systems based on hydroponic plant growth to three classes of surfactants.

Anionic (sodium laureth sulfate, SLES), amphoteric (cocamidopropyl betaine, CAPB) and nonionic (alcohol polyethoxylate, AE) surfactants were added to separate nutrient film technique (NFT) hydroponic systems containing dwarf wheat (Triticum aestivum cv. USU Apogee) in a series of 21 day trials. Surfactant was added either in a (1). temporally dynamic mode (1-3 g surfactant m(-2) growing area d(-1)) as effected by automatic addition of a 300 ppm surfactant solution to meet plant water demand, or (2). continuous mode (2 g surfactant m(-2) growing area d(-1)) as effected by slow addition (10 mLh(-1)) of a 2000 ppm surfactant solution beginning at 4d after planting. SLES showed rapid primary degradation in both experiments, with no accumulation 24 h after initial addition. CAPB and AE were degraded less rapidly, with 30-50% remaining 24 h after initial addition, but CAPB and AE levels were below detection limit for the remainder of the study. No reductions in vegetative growth of wheat were observed in response to SLES, but biomass was reduced 20-25% with CAPB and AE. Microbial communities associated with both the plant roots and wetted hardware surfaces actively degraded the surfactants, as determined by monitoring surfactant levels following pulse additions at day 20 (with plants) and day 21 (after plant removal). In order to test whether the biofilm communities could ameliorate phytotoxicity by providing a microbial community acclimated for CAPB and AE decay, the continuous exposure systems were planted with wheat seeds after crop removal at day 21. Acclimation resulted in faster primary degradation (>90% within 24h) and reduced phytotoxicity. Overall, the studies indicate that relatively small areas (3-5m(2)) of hydroponic plant systems can process per capita production of mixed surfactants (5-10 g x person(-1)d(-1)) with minimal effects on plant growth.

Biofilms↗

PubMed2004

Nitrogen fertilization, soil nitrate accumulation, and policy recommendations in several agricultural regions of China.

Excessive nitrogen (N) fertilization and decreasing N recovery rates by crops have caused dramatic increases in non-point source pollution from agriculture in China. The rate of N fertilization across the country varies widely among regions and crops, depending on the stage of economic development. For example, N application rates in the eastern regions and on cash crops are far higher than in western regions of the country and on cereal crops. Moreover, N application rates in wealthier regions are higher than recommended by the Chinese Academy of Sciences. To successfully achieve environmental protection as well as high crop yields, China must formulate relevant agricultural policies to encourage farmers in economically developed areas to reduce their N fertilization rate while also issuing conventional fertilization recommendations for small-scale farming systems and the expanding cultivation of cash crops.

Agriculture↗

PubMed1996

Bioregenerative life support systems for long-term space habitation: a conceptual approach.

Life support systems represent one of the most critical aspects of human space exploration. Future long-term missions such as the establishment of human-tended Lunar and Martian bases require closed life support systems. A conceptual approach to an Engineered Closed/Controlled EcoSystem incorporating bioregenerative capabilities by integrating humans, plants, and waste management processes is presented. The integration of physical/chemical and biological waste treatment processes is suitable for supporting plant growth through hydroponics and materially closing the human and plant metabolic loops. This conceptual design separates wastes into individual loops for treatment according to the specific metabolic needs of humans and plants. The means through which an integrated Engineered Closed/Controlled EcoSystem meets the life support objectives of long-term space habitation are summarized.

Biomass↗

PubMed2006

Potato (Solanum tuberosum L.).

Potato (Solanum tuberosum L.) is a globally important crop plant producing high yields of nutritionally valuable food in the form of tubers. It has been the focus of substantial study because of its use both as a staple food crop and as a potentially significant source of compounds of interest. This has included the development and application of transgenic technology for introducing novel traits of fundamental and applied interest. This chapter describes a rapid, efficient, and cost-effective system for the routine transformation of this crop plant at rates above 40% efficiency, calculated as the mean number of Southern blot- confirmed independent transgenics per number of internodal explants originally plated. Internodal sections are co-cultivated with Agrobacterium tumefaciens and subjected to a two-stage callus induction/shoot outgrowth system under kanamycin selection. Shoot regeneration rates are high using the described method, and excised independent shoots rooting from the cut end of the stem after two further subcultures on kanamycin are 95% certain to be transformed. The transgenic status can be confirmed by molecular analysis and the plants grown on for tuber production enabling a wide spectrum of further studies.

Agrobacterium tumefaciens↗

PubMed1997

An overview: recycling nutrients from crop residues for space applications.

Without some form of regenerative life support system, long duration space habitation or travel will be limited severely by the prohibitive costs of resupplying air, water, and food from Earth. Components under consideration for inclusion in a regenerative life support system are based on either physicochemical or biological processes. Physicochemical systems would use filtration and elemental phase changes to convert waste materials into usable products, while biological systems would use higher plants and bioreactors to supply crew needs. Neither a purely biological nor strictly a physicochemical approach can supply all crew needs, thus, the best each approach can offer will be combined into a hybrid regenerative life support system. Researchers at Kennedy Space Center (KSC) Advanced Life Support Breadboard Project have taken the lead on bioregenerative aspects of space life support. The major focus has been on utilization of higher plants for production of food, oxygen, and clean water. However, a key to any regenerative life support system is recycling and recovery of resources (wastes). In keeping with the emphasis at KSC on bioregenerative systems and with the focus on plants, this paper focuses on research with biologically-based options for resource recovery from inedible crop residues.

Biodegradation, Environmental↗

PubMed1996

Mission simulation as an approach to develop requirements for automation in Advanced Life Support Systems.

This paper examines mission simulation as an approach to develop requirements for automation and robotics for Advanced Life Support Systems (ALSS). The focus is on requirements and applications for command and control, control and monitoring, situation assessment and response, diagnosis and recovery, adaptive planning and scheduling, and other automation applications in addition to mechanized equipment and robotics applications to reduce the excessive human labor requirements to operate and maintain an ALSS. Based on principles of systems engineering, an approach is proposed to assess requirements for automation and robotics using mission simulation tools. First, the story of a simulated mission is defined in terms of processes with attendant types of resources needed, including options for use of automation and robotic systems. Next, systems dynamics models are used in simulation to reveal the implications for selected resource allocation schemes in terms of resources required to complete operational tasks. The simulations not only help establish ALSS design criteria, but also may offer guidance to ALSS research efforts by identifying gaps in knowledge about procedures and/or biophysical processes. Simulations of a planned one-year mission with 4 crewmembers in a Human Rated Test Facility are presented as an approach to evaluation of mission feasibility and definition of automation and robotics requirements.

Automation↗

PubMed2026

Generational variation and stabilization in resynthesized allotetraploid Brassica juncea derived from diploid progenitors B. rapa and B. nigra.

BACKGROUND: Polyploidy is a major driver of plant evolution and crop improvement, generating novel variation in morphology, physiology, and agronomic traits. Brassica juncea (AABB, 2n = 36), a natural allotetraploid derived from B. rapa (AA) and B. nigra (BB), is an important oilseed and vegetable crop; however, its narrow genetic base limits further breeding gains. Resynthesized B. juncea (RBJ), developed from known progenitors, provides a tractable system to investigate polyploid stabilization, trait diversification, and generational variation. This study evaluated RBJ across nine generations (F1-S8) to elucidate generational variation in morphological, molecular, cytological, and oil content traits during progressive stabilization. RESULTS: Substantial variation was observed for key yield-related traits, including siliqua length, seeds per siliqua, and thousand-seed weight. High estimates of heritability, genotypic variance, and genetic advance indicated their potential utility in selection based improvement. Comparative analyses revealed a clear generational progression, characterized by relatively enhanced performance in early generations, increased recombination-driven variability in intermediate generations, and the partial stabilization of several traits in later generations. Generation mean analysis suggested the involvement of additive, dominance, and epistatic gene effects in trait inheritance. Molecular analysis using SSR markers confirmed the amphidiploid origin and genomic integrity of RBJ generations. Cytological assessments, pollen viability assays, and flow cytometric analysis collectively demonstrated stable chromosome numbers, improved fertility, and maintenance of ploidy stability across successive generations. CONCLUSIONS: The study provides valuable insights into the generational variation and stabilization of morphological, molecular, and oil content traits in resynthesized B. juncea. The findings suggest that variability arising from polyploidization and interspecific hybridization undergoes gradual reorganization across successive generations, leading to increased trait stabilization and more consistent expression of selected agronomic characteristics. Collectively, these results contribute to the understanding of early stabilization processes in RBJ, highlighting resynthesized polyploids as useful systems for studying variation and stabilization in allopolyploid crops.

Mustard Plant↗

PubMed1994

Man as a component of a closed ecological life support system

Material support of all manned space flights so far has been provided from a prestored stock of substances or replenished from the Earth's biosphere. Exploration of space will, however, become real only when man is able to break away from Earth completely, when he will be accompanied by a system providing everything necessary to sustain full-valued life for an unlimited time. The only known system to date meeting this requirement is the Earth's biosphere. To break away from his cradle, as K.E. Tsiolkovsky called Earth, it is necessary to devise a life support system functionally similar to the natural biosphere. This need not be similar in structure to the vast diversity of trophic relationships available on Earth, but requires the solution of a multitude of various problems of an ecological, physiological, engineering and social-psychological nature. Human life-support systems based on biological regeneration of environments in small volumes have been studied at the Institute of Biophysics (Siberian Branch of the Russian Academy of Sciences) over many years. This work has resulted in the design of Bios-3, a biologically-based self-sustained human life support system.

Blood Cell Count↗

PubMed1992

A study of biohazard protection for farming modules of lunar base CELSS.

For the Closed Ecological Life Support System (CELSS) of a manned lunar base which is planned to be built on the moon early in the 21st century, several proposed programs exist to grow vegetables inside a farming module. At the 40th IAF (Malaga, 1989) the author et al presented a proposal for supplying food and nutrients to a crew of eight members, a basic concept which is based on growing four kinds of vegetables. This paper describes measures for biohazard protection in farming modules. In this study, biohazard protection means prevention of the dispersion of plant diseases to other plant species or other portions of farming beds.

Agriculture↗