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At least 19 recordsLinked to original sources
PubMed1985

Lead induction of crop dysfunction in pigeons through a direct action on neural or smooth muscle components of crop tissue.

Lead acetate solutions administered p.o. to pigeons produce crop stasis. Crop dysfunction may be an indirect effect on crop activity by a direct interaction with the cerebellum or some other site associated with lead-induced ataxia. Alternatively, crop stasis may be due to the direct interaction of lead with sites on the smooth muscle or neural elements in crop tissue. A behavioral test for ataxia was performed on pigeons given lead by crop intubation or i.m. injection. Blood lead concentrations were also monitored. Lead-induced ataxia was separable from lead-induced crop dysfunction depending on the route of lead administration, suggesting that lead-induced crop stasis is not secondary to toxicity at a site associated with ataxia. Intramuscular treatment produced crop stasis more readily than did crop intubation. This probably reflects different mechanisms of absorption and metabolism. A Tris-succinate medium was devised which accommodated the solubility characteristics of lead, permitting studies of crop tissue in vitro. Lead chloride added to crop tissue in tris-succinate medium caused a concentration-related reversible relaxation. Crop circular muscle was more sensitive to Pb++ than was longitudinal muscle, in agreement with the effects of other agonists. The EC30 of crop circular smooth muscle in plasma was 1000 microM PbCl2 compared to 3 microM in Tris-succinate medium. The results suggest that lead induces crop dysfunction by acting either directly on crop smooth muscle or on neural elements in crop tissue.

Animals↗
PubMed2026

Bioinformatics in crop research: using genomic data for crop improvement.

Sustainable crop development aims to maintain or increase yields while reducing environmental impact and managing the challenges imposed by climate change. As the global population grows and arable land becomes scarcer, the integration of molecular breeding with bioinformatics has emerged as an effective strategy for long-term crop improvement. Bioinformatics enables researchers to analyze and interpret the vast quantities of genetic data generated by high-throughput sequencing, making it possible to identify molecular markers, candidate genes, and regulatory networks linked to specific agronomic traits, which breeders then translate into focused, ecologically sustainable breeding programs. This approach has enabled major progress across several fronts: the identification of genes conferring resistance to biotic stressors (pests, pathogens) and abiotic stressors (drought, salinity, heat); the development of nutrient-efficient, low-input crop varieties; the improvement of agronomic performance and nutritional quality through identification of yield- and quality-related genes; and the conservation and deployment of genetic diversity to safeguard long-term breeding sustainability. By combining genomic data with precision breeding techniques, researchers are developing crops that are better adapted to a growing population and a changing climate, positioning the integration of molecular breeding and bioinformatics as a central pillar of future global food security.

bioinformatics↗
PubMed1990

Yeasts and fungi occurring in ensiled whole-crop maize and other ensiled vegetable crops.

The yeast flora of whole-crop maize ensiled for two weeks was predominated by Candida holmii, C. lambica, C. milleri, Hansenula anomala and Saccharomyces dairensis. Inoculation with other yeast species reported in the literature to prevail in maize or wheat silages did not alter the yeast flora. At 25 or 30 degrees C the ascomycetous fermentative species found at 20 degrees C were accompanied with ascomycetous non-fermentative fungi, i.c. Exophiala jeanselmei and Verticillium psalliotae, by the non-fermentative imperfect basidiomycetous yeast Rhodotorula mucilaginosa and by the weakly fermentative imperfect ascomycetous yeast Trichosporon adeninovorans. The yeast flora of other vegetable crops, ensiled at 20 degrees C for two weeks, was predominated by the same species that prevailed in ensiled maize, provided the crop did not contain mustard oils or menthol. If these compounds occurred in the crops, the yeast flora was predominated by nonfermentative species like Candida famata, Stephanoascus ciferrii, Rhodotorula minuta, Rh. rubra and Trichosporon cutaneum.

Animal Feed↗
PubMedDate not supplied

[Characteristics of the microflora of soddy-podzol soil during single-crop cultivation of agricultural plants and during crop rotation].

Structural organization of microbial populations in soddy-podzolic soil was studied during growth of agricultural plants in monoculture and in crop rotation. The content of bacteria and their biomass decreased when plants were grown in monoculture. The content of actinomycetes, bacilli and oligonitrophilic microorganisms increased in soil during crop rotation as compared with monocultures, suggesting a higher rate of mobilization processes. The content of microscopic fingi in soil increased when lupine was grown in monoculture. Growth of plants in monoculture affects the cenotic structure of soil microflora. The composition of active soil microflora was characterized by a wider spectrum of microbial forms during crop rotation of monocultures.

Agriculture↗
PubMed1977

Intensive fattening of beef cattle by stall feeding on the Lilongwe Plain, Malawi. II. Utilisation of crop residues, crop by-products and leucaena.

Experiments were conducted over three dry seasons to investigate the value for fattening beef cattle, of crop residues (maize stover, groundnut haulm) and madeya (maize bran) with varying levels of dried leucaena leaf or cottonseed cake. The inclusion of groundnut haulm in the roughage increased animal performance when madeya was restricted. Increasing the protein content of the madeya supplement but restricting the quantity of madeya fed did not influence liveweight gain although the efficiency of concentrate conversion was enhanced. Restricting the amount of maize stover and feeding madeya to appetite had no significant effect on liveweight gain, but the inclusion of leucaena up to a level of 12 per cent crude protein improved animal performance. There were no differences between cottonseed cake or leucaena when fed with madeya at the same levels of crude protein.

Animal Feed↗
PubMed1991

The nutrition and health impact of cash cropping in west Africa: a historical perspective.

The impact of cash cropping in West Africa cannot be isolated from its social and historical background. Among the many changes brought to West African economies by cash cropping since the beginning of the century, the present document shows how the extension of trade with European merchants and colonizers created new sets of values and criteria for wealth. Food crops gradually lost their prominent cultural and economics roles to the benefit of export crops or goods. Traditional systems of agricultural production were profoundly disrupted by military actions. They imposed colonial rule and control of trade of tropical crops and goods. Forced labor and compulsory (poorly paid) work assignments were instituted for private and public enterprises: construction of roads, railways, public buildings and plantations. The main justification was the need for cheap labor to cultivate, transport and build roads for the extraction of raw materials. This in turn caused massive migrations from countries such as Burkina Faso (Upper Volta) to Ivory Coast. Cash cropping made systematic collection of taxes possible. An imposition on a per capita basis became the rule and the major incentive of small farmers to engage in commercial farming. Cash cropping made also possible extensive monetarization of West Africa. This results in both favorable and unfavorable effects on the quality of the diet. In profoundly disrupted traditional societies, the diffusion of new consumption patterns was easier and faster. It led to massive food imports of wheat, rice, sugar, alcohol, etc. Cash cropping was (and still is) practiced as a 'mining' agriculture, exhausting soils and deteriorating their fertility for extended periods of time. In the Sudanian and Sahelian zones cash cropping conflicted with the cultivation of grains because peak demands for labor were similar. Therefore, millet and sorghum production declined. Cash cropping was developed in response to the need of European economies for tropical products. However, colonization as a tool to obtain these raw materials was highly inefficient and associated with a considerable misuse of public funds. Together with cash cropping extension was created a network of intermediaries of large European corporations and shopkeepers who would efficiently drain all the earnings from cash cropping away from productive agricultural investments. It made possible the birth of local bourgeoisies and states dedicated almost exclusively to the extraction of a surplus value from the peasantry through cash cropping. It led to a displacement of the role of women; by attributing to them the less profitable food crops, the new production system managed to feed local cities and migrant workers at low cost. Cash cropping provides indirectly a new mean of exploiting women's labor.(ABSTRACT TRUNCATED AT 400 WORDS)

Africa, Western↗
PubMed1975

Prolactin binding activity on the crop sacs of juvenile, mature, parent and prolactin-injected pigeons.

Specific prolactin (PRL) binding activity of lactoperoxidase catalyzed 125I-labeled ovine-PRL was determined in a membrane-rich particulate fraction of pigeon crop sacs. Levels of TSH, LH or FSH as high as 1000 ng each were unable to displace the 125I-o-PRL bound to 600 mug of crop sac microsomal protein, whereas competitive displacement was achieved with as little as 0.5 ng unlabeled PRL. Ovine GH exhibited some cross reactivity when incubated in amounts greater than 500 ng, but this could be accounted for by its stated PRL contamination. Specific PRL binding activities were determined in juvenile and mature pigeons with unstimulated crop sacs, and parent pigeons with 'crop milk' and mature birds injected with PRL for 4 days. Crop sacs from juvenile birds contained approximately twice as much binding activity as crop sacs from mature pigeons. Parent and PRL injected pigeons, each with proliferated crop sac epithelium, exhibited 4-5 times as much specific PRL binding as the non-proliferated crops from juvenile or mature birds. These results show that the pigeon crop sac contains specific binding sites for PRL, and that the crop sac response to PRL is associated with an increase in PRL binding activity.

Age Factors↗
PubMed1978

[Effect of plant residues on the parasitic activity of soilborne pathogens and the saprophytic microflora of the soil. III. Influence of rye and rape grown as winter catch crop on the incidence of Cercosporella herpotrichoides Fron (author's transl)].

In a five-years field trial, the influence of two winter catchcrops, rye and rape, upon the incidence of Cercosporella herpotrichoides has been studied. The winter catch-crops had been repeated three times, followed either by stubble-crop or without in fall of the fourth year. The variants (blocks) had been completed by two variants without catch-crop, either carefully cultivated or overgrown with weeds. Each of the four blocks had been divided three times to be grown with three different crop sequences containing 80%, 60% (with the insusceptible corn), or 40% haulm fruit, respectively. Each of the 12 variants had been divided into two parts by continuous fallow stripe, one part being artificially infested with the pathogen in the beginning (1st winter wheat). In the 2nd, 3rd, and 4th year, only spring crops were grown, followed by winter wheat in the 5th year. The final exploration resulted in a medium to heavy degree of infection, being significantly higher in the 80% cereal crop sequence than in the 60% and 40% sequences. Concerning the catch-crops, infection in the rye variants was equal or significantly lower than in the carefully cultivated variants without catch-crop. On the other hand, infection of the rape variants had become significantly higher than that of the catch-crop-free ones, about as heavily as in the weed-infested variants. From fall 1966 to summer 1969, the development of the saprophytic soil microflora and several other edaphic parameters had been investigated. Remarkable differences in intensity of disintegration have been observed under the influence of the main crops, cereals or potatoes, respectively, but no differences could be stated resulting from the matter of disintegration--residues of rye or rape--, which might interpret the contrasting effects on the pathogen. Too, no indication for antagonistic activity of bacteria or actinomycetes has been noted. The results are compared with known facts of Cercosporella and of other soil borne pathogens. The difference in biology of Cercosporella on the one hand, and of root infecting fungi on the other hand seems to be most important to explain the results obtained.

Actinomycetales↗
PubMed1975

Effect of prolactin on lipoprotein lipase in crop sac and adipose tissue of pigeons.

The effect of prolactin on lipoprotein lipase activity of crop sac, omental adipose tissue, and esophagus was studied in adult female pigeons. Prolactin injected for 4 days, 1 mg/day, increased lipoprotein lipase activity from 17 to 177 U/g in crop sac and from 68 to 118 U/g in adipose tissue, but had no effect on the activity in esophagus, 4 U/g. (10 = 1 mumol of chylomicron triglyceride hydrolyzed to free fatty acid and glycerol per hour.? Prolactin increased the weight of crop sac from 1.4 to 7.2 G. The effect of prolactin on lipoprotein lipase activity and weight of crop sac occurred mostly during the 3rd and 4th days of treatment, whereas the effect on the activity of adipose tissue occurred later, during the 4th day of treatment. Crop "milk" collected from pigeons injected with 2 mg of prolactin daily for 4 days contained a small amount of lipoprotein lipase activity, 12 U/g, is smaller than 10% of that found in crop sac. The finding of markedly increased lipoprotein lipase activity in crop sac of prolactin-treated pigeons suggests that blood triglyceride may be used by crop sac for the formation of crop milk lipid.

Adipose Tissue↗
PubMed1975

Candida species and crop mycosis in broiler chickens.

A mycological survey of the crops of approximately 100 healthy birds from each of 6 grow-out operations revealed that the incidence of Candida in the crops ranged from 17.4 to 51.5% with a mean value of 32.3%. The population of Candida in the crops of birds found positive was of low magnitude in the majority of the chickens examined. Of the 573 birds examined in this study less than 1% exhibited visible lesions attributable to Candida. C. albicans comprised 95% of the isolates while C. ravautii, C. salmonicola, C. gulliermondi, C. papapsilosis, C. catenulata and C. brumptii comprised the remainder. The incidence and number of Candida in the crop was related apparently to management practices on the farm. The crops from four field outbreaks of crop mycosis were also studied. Three of the four cases of crop mycosis were characterized by multiple strains of C. albicans in the crop. In one case, C. parapsilosis also was isolated from the crop.

Animals↗
PubMed2025

Synergic impact mechanisms of cover crop residue on Cd and As availability and native organic carbon mineralization in Cd and As co-contaminated paddy soil.

The synergic impacts of cover crop residue on heavy metal and metalloid availability and soil organic carbon (SOC) mineralization in contaminated paddy soil and the underlying microbial mechanism remain unclear. This study investigated the availability of cadmium (Cd) and arsenic (As) and mineralization of native SOC in paddy soil treated with 0, 0.4 %, 0.8 % and 1.2 % of δ13C-labeled cover crop residue (Astragalus sinicus L.) via 90-day incubation experiments, the related functional genes and functional microbial communities were analyzed using metagenomic binning assembly. Cover crop residue with addition rate from 0.4 % to 1.2 % significantly decreased available Cd by 56 %-85 % but increased available As by 39 %-66 % compared to the control treatment. Cover crop residue resulted in a positive priming effect on native SOC mineralization but benefited SOC sequestration. Cover crop residue increased the abundance of genes encoding iron reductase (mtrABC, pilA, omcB), sulfate reductase (sir, fpr), As(V) reductase (ArsC), organic carbon hydrolases, methanogenesis, and methylotrophy. Genomes associated with Chloroflexota and Bacteroidota encoded all these key pathways, and their abundance increased with cover crop residue application. Cover crop residue decreased soil Eh, dissolved crystalline iron oxides, enriched specific microorganisms, including Chloroflexota and Bacteroidota, and then synergistically promoted the decrease in Cd availability and the increase in As availability and native SOC mineralization in the examined paddy soil. These findings provided practical and feasible guidance for achieving both safe production and carbon sequestration in contaminated paddy fields, highlighting the requirement to cautious utilization of cover crop residue in As-contaminated paddy fileds.

Soil Pollutants↗
PubMed1992

The influence of the stomach on crop function and feeding behavior in domestic turkeys.

We tested the hypotheses that motility of the crop and muscular stomach are coordinated and that the stomach exerts primary control over crop filling and emptying in domestic turkeys. Simultaneous recordings of motility of the crop, esophagus, and stomach with implanted strain gauge transducers and visual observations of food passage using image intensification radiography revealed an inverse relationship between the frequency of stomach and crop contractions. Artificially filling the stomach of a fasted turkey with a food slurry prior to feeding did not increase crop filling during the first morning meal, but it did inhibit crop emptying in fasted turkeys by markedly reducing the number of crop contractions. Artificially filling the crop of fasted turkeys prior to the first morning meal did not decrease the amount of feeding activity or the total amount of food consumed during that meal. It is suggested that meal termination is associated with the degree of inhibition of esophageal peristalsis.

Animals↗
PubMed2026

Adaptive evolution of polyploid crops.

Crop evolution represents a fundamental biological process through which plants respond to selection in different environments. This encompasses mechanisms operating at multiple scales of biological organization, including genetic and epigenetic regulation and higher-order interactions among molecular complexes. This Review synthesizes how polyploidy shapes crop evolution by generating duplicated genes, driving genome reorganization, altering dosage relationships and promoting regulatory divergence, which together influence crop metabolism, physiology, development and environmental responses. We focus mainly on the mechanisms underlying adaptation in polyploid crops, including the consequences of gene and genome duplication, genome reorganization and subfunctionalization. We also examine how hybridization, phenotypic plasticity and crop-microbiome interactions intersect with polyploidy to expand or constrain adaptive potential. Together, these processes affect crop survival, fitness and breeding value under changing environments. We suggest that future research connect polyploid genome architecture with experimentally validated signatures of selection and field performance to make better use of polyploidy-derived variation in crop improvement.

Polyploidy↗
PubMed2026

Herbicide Resistance Genes in Crops: Mechanisms, Progress, and Future Perspectives.

While previous reviews have largely focused on individual crops or single target-site mechanisms, the full-chain comparative landscape across major cereal crops remains unexplored. Here, we fill this critical gap by providing the first systematic, cross-crop comparative review that spans herbicide targets, resistance mechanisms, and breeding applications across four major cereals-rice, maize, wheat, and sorghum. Weed infestation is a serious constraint on crop production. Chemical weed control faces challenges such as herbicide resistance evolution and ecological risks. Developing herbicide-resistant varieties is a fundamental approach to achieve green and sustainable weed management. This review systematically summarizes research progress on herbicide resistance genes from three aspects: herbicide classification, resistance mechanisms, and crop breeding applications. It highlights key differences among four major cereal crops (rice, maize, wheat, and sorghum) in resistance-gene discovery and translational progress. Rice has the richest target-site resistance-gene resources. Maize leads in commercialization of transgenic herbicide resistance. Wheat focuses on endogenous precise editing due to genome complexity and regulatory constraints. Sorghum relies on specific mutations to serve cereal-legume intercropping systems. Based on this comparison, this review identifies the core trends in resistance breeding: from single-gene to multi-gene stacking, and from exogenous gene introduction to endogenous gene editing. It also points out common bottlenecks, including insufficient systematic mining of resistance-gene resources, lagging elucidation of non-target-site resistance regulatory networks, and strong genotype dependence in genetic transformation. Future efforts should focus on exploring broad-spectrum resistance genes, optimizing precise editing technologies, and developing sustainable resistance management strategies. This review provides a theoretical framework and practical references for molecular breeding of herbicide-resistant crops.

crop breeding↗
PubMed2026

CROP: a feature-independent context-aware method for CRISPR-Cas9 frameshift prediction.

MOTIVATION: The CRISPR-Cas9 complex has revolutionized genome-editing technologies. By designing a 20 nt-long guide RNA, a Cas9 nuclease can be guided to cleave almost any genomic target site (followed by NGG). The cleavage induces double-stranded DNA breaks, which are then repaired by cellular pathways. Accurate CRISPR-Cas9 repair-outcome prediction is essential for designing guide RNAs with desired genomic effects, such as gene knockout. A central challenge is quantifying the rate of frameshifts, i.e. repair-outcomes that lead to a change in the local length that is not a multiple of three. Previous methods for frameshift-rate prediction were trained on only a few experimental or cellular contexts, mostly relied on manually defined microhomology features, and were limited by sparse features and class labels. RESULTS: We developed CROP, a feature-independent context-aware repair-outcome prediction method. By aggregating specific repair outcomes as Δlength classes, CROP overcomes class sparsity. We designed CROP to work with variable input sequence lengths and output classes to utilize multiple datasets simultaneously. We benchmarked CROP against state-of-the-art repair-outcome prediction methods over 18 datasets, which we curated and standardized from various studies. Across all datasets, CROP outperformed all competing methods in frameshift-rate prediction. We performed cross-experiment and cross-cellular frameshift-rate predictions to investigate the generalizability of repair mechanisms. Finally, we show that CROP learned microhomology principles from raw sequences without explicit feature engineering, establishing an end-to-end architecture for CRISPR-Cas9 repair-outcome prediction that learns from multiple datasets. AVAILABILITY AND IMPLEMENTATION: CROP is available at https://github.com/OrensteinLab/CROP.

CRISPR-Cas Systems↗
PubMed1979

The nutritional significance of root and tuber crop development as staples in the Caribbean community.

The competition between cereals and root crops as CARICOM staples is described. The move to substitute locally grown food for imported wheat is shown to favor root crop development in the region. Against this background, traditional nutrition-prompted objections to wheat substitution by root crops are examined. Evidence is cited to show the essential adequacy of protein in root crops, except plantain and cassava and for all humans except perhaps some infants. The low protein in cassava and plantain, it is proposed, can be easily overcome in the process of local root crop development. Finally, it is argued that there exists the potential to obtain cheap calories from root crops. This and the generation of economic activity among small farmers, concomitant with root crop development, are seen as possible indicators of good nutrition for the region in the future.

Diet↗
PubMed1976

Composition of crop and gizzard contents in the laying hen.

Crop and gizzard contents were analysed at six stages of egg formation. 2. The crop was empty during the day and full during the night while the gizzard contained a constant amount of dry matter. The water content of the crop did not change but that of the gizzard was at a minimum just after the ovulation and at a maximum 18 h later. 3. The osmotic pressure of the gizzard contents remained constant and close to that of the blood; that of the crop contents was almost isotonic at oviposition but hypertonic 18 h later. In both organs the pH of the liquid phase varied cyclicly with the egg formation and was lowest during egg shell deposition. 4. The Na+, K+ and Cl- contents of the crop liquid phase did not vary but Ca2+ increased with decreasing pH.Na+ and K+ were also constant in the gizzard liquid phase but Cl- and Ca2+ increased during shell formation. 5. It is concluded that the amount of HCl secreted by the proventiculus is related to egg shell deposition and that calcium solubilisation depends on microbial fermentation in crop and HCl secretion by proventriculus.

Animals↗