Application of crop growth simulation and mathematical modeling to supply chain management in the Thai sugar industry

The poorly integrated cane supply planning between mills and cane growers in the Northeast of Thailand generates an excess of cane supplies that exceeds the mills’ capacity during the peak of harvest season. Each grower individually determines his/her cultivation plan by selecting planting dates and cultivars based on one’s own preference without taking into account the individual mill’s capacity and other growers’ plans. This situation causes most sugarcane grown in this area to reach its mature stage at the same period. In this study, we propose a framework of cultivation planning to cope with the problem. The focus of the cultivation plan is a long-term plan to determine the cultivation time, the cultivar selection and the corresponding prospective harvesting time window for each field such that overall sugar production is optimized.The crop growth model and a mathematical model are employed for yield simulation and optimization task. The crop growth model enables decision-makers to visualize cane production of each individual field at different dates with different cultivars and allow decision-makers to apply the mathematical programming to cultivation planning. The suggested framework has the potential to increase sugar production by 23% when compared to the traditional method.     

Effect of L‐carnitine on maturation,cryo‐tolerance and embryo developmental competence of bovine oocytes

In this study, the effects of the addition of L‐carnitine in in vitro maturation (IVM) medium for bovine oocytes on their nuclear maturation and cryopreservation were investigated; they were matured in IVM medium supplemented with 0.0, 0.3, 0.6 and 1.2 mg/mL of L‐carnitine (control, 0.3, 0.6 and 1.2 groups, respectively) and some of them were vitrified by Cryotop. Moreover, the effects of L‐carnitine during in vitro fertilization (IVF) and in vitro culture (IVC) on the developmental potential and quality of IVF embryos were also examined. A significantly higher maturation rate of oocytes was obtained for 0.3 and 0.6 mg/mL groups compared with the control (P < 0.05). The blastocyst formation rate in the 0.6 group was significantly improved, whereas the rate in the 1.2 group was significantly decreased when compared with the control group (P < 0.05). No significant difference was found in embryo development between the control and the L‐carnitine group after oocyte vitrification. Supplementation of IVF and IVC media with L‐carnitine had no effect on development to the blastocyst stage of IVM oocytes treated with 0.6 mg/mL L‐carnitine. In conclusion, the supplementation of L‐carnitine during IVM of bovine oocytes improved their nuclear maturation and subsequent embryo development after IVF, but when they were vitrified the improving effects were neutralized.     

Effect of incorporating ragi (Eleusine Coracana) husk in semisynthetic diets

The effect of including ragi husk in the diet, at the 8 per cent level, on growth and body composition of pair-fed albino rats was studied. Even on equal food intake by both control as well as the experimental animals, the incorporation of ragi husk promoted better growth, nitrogen retention and protein efficiency ratio. Protein content of the carcass and liver of rats fed diets containing ragi husk was higher than the control group. The growth response of rats fed ragi husk appeared to increase with the content of nitrogen in the husk.     

Evaluation of Agronomic Traits in Chromosome Segment Substitution Lines of KDML105 Containing Drought Tolerance QTL under Drought Stress

Drought is a major abiotic constraint to rice production in rainfed lowland and insufficiently irrigated areas.The improvement of drought tolerant varieties is one of the strategies to reduce the negative effects of drought.Quantitative trait loci(QTLs) for primary and secondary traits related to drought tolerance(DT) on chromosomes 1,3,4,8 and 9 that determined from double haploid lines derived from a cross between CT9993 and IR62266 were introgressed and dissected into small pieces in the genetic background of Khao Dawk Mali 105(KDML105) to develop chromosome segment substitution line(CSSL) population.The CSSLs were evaluated at the reproductive stage for their agronomic performance and yield components under drought stress,and results were compared with irrigated condition.The flowering of CSSL lines was 6 to 7 d earlier than KDML105.The mean values of grain yields in the CSSLs were higher than KDML105 under drought and irrigated conditions.At irrigated condition,the grain yields of introgression lines carrying DT-QTLs from chromosomes 4 and 8 were higher than that of KDML105,whereas other traits showed little difference with KDML105.Analysis indicated that grain yield has positive correlation with plant height,tiller and panicle number per plant,and total grain weight per plant under drought stress while negatively correlated with days to flowering.As mentioned above,CSSLs showing good adaptation under drought stress can be used as genetic materials to improve drought tolerance in Thai rainfed lowland rice breeding program,and as materials to dissect genes underlying drought tolerance.     

Pulmonary Edema Due to Oral Gavage in a Toxicological Study Related to Aquaporin-1, -4 and -5 Expression

A one-time oral gavage can be enough to cause of alveologenic edema with higher expression of AQP-1 and -4 than that with repeated-dose oral gavage, which caused both profound perivascular edema and hydrostatic pressure edema, while AQP-5 was similarly expressed. The alteration of AQPs expression was probably related to alveolar fluid clearance across the alveolar and bronchiolar epithelium in different stages of lung injury. The results clarified the type of lung edema in acute and sub-chronic toxicity studies without treatment related effect of tested material. The pathogenesis of pulmonary edema due to oral gavage toxicological study is associated with the cellular immune response to the reflux materials. Mast cell and leukocyte accumulation may contribute to increase vascular permeability leading to permeability edema. The increase in alveolar septum epithelium, perivascular and peribronchial cuffing, accumulation alveolar lipid containing macrophage and medial hyperplasia of the pulmonary artery might have been caused to increase airway resistance, which resulted in hydrostatic pressure edema.     

Effect of restricted feeding on metabolic adaptations of Kamphaengsaen and crossbred Brahman heifers

Metabolic adaptation during feed deprivation was determined in five Kamphaengsaen (KPS) and six crossbred Brahman (Crossbred Bra) heifers. All heifers were fed at the rate of 85% of the metabolizable energy requirement for maintenance. At the end of 20 days of restricted feeding, the Crossbred Bra heifers lost more bodyweight than the KPS heifers (12.0 vs. 7.2 kg) (P < 0.05). In both groups of heifers there was a similar depletion of back‐fat thickness, however, the loin eye area of the Crossbred Bra heifers decreased more than KPS heifers (8.43 vs. 0.92%; P < 0.05). Feed restriction elevated the rate of lipolysis in adipose tissue, resulting in increased nonesterified fatty acids concentrations in plasma. The Crossbred Bra heifers had a greater serum high density lipoprotein triacylglycerol concentration than the KPS heifers (17.02 vs. 9.53 mg/dL; P < 0.05). This would suggest that the hepatic tissues in the Crossbred Bra heifers exported more triacylglycerols as very low density lipoprotein than in the KPS heifers. During the feed restriction period, the plasma β‐hydroxybutyrate concentration for the heifers was elevated; however, Crossbred Bra heifers shown less plasma β‐hydroxybutyrate concentration than KPS heifers (242 vs. 326 µmol/L; P < 0.05). This may be due to the difference in very low density lipoprotein secretion between the two groups of heifers. There were significant differences in plasma urea‐nitrogen and plasma glucose concentrations (P < 0.05), with the KPS heifers showing less extensive plasma urea‐nitrogen concentration and hypoglycemia, whereas the Crossbred Bra heifers had more extensive plasma urea‐nitrogen concentration and euglycemia. These two metabolites were suggestive of a ketogenic effect on muscle protein catabolism. In conclusion, it was found that the underfed KPS heifers utilized ketone bodies as their energy source, thus limiting body protein degradation, whereas the Crossbred Bra adapted to feed deprivation by exhibiting an auto‐regulation mechanism for ketogenesis and broke down body protein extensively to satisfy their demand for glucose.     

Molecular characterization and expression of the Prostaglandin reductase 1 gene and protein during ovarian development of the giant tiger shrimp Penaeus monodon

Prostaglandin reductase 1 (PTGR1; also called NADP⁺-dependent leukotriene B4 12-hydroxydehydrogenase, LTB4DH) is the key enzyme responsible for biological inactivation of prostaglandins and related eicosanoids. In this study, the full-length cDNA of PTGR1 in the giant tiger shrimp (Penaeus monodon) was characterized. PmPTGR1 was 2405 bp in length with an ORF of 1035 bp encoding a polypeptide of 344 amino acids. Interestingly, its 3′ UTR contained the nucleotide sequence (825 bp) that significantly matched positions 3–277 (with 4 amino acid variants) of the deduced P. monodon peritrophin2 protein. PmPTGR1 was more preferentially expressed in ovaries than testes of P. monodon broodstock. In intact broodstock, PmPTGR1 was up-regulated in early cortical rod (stage III) ovaries (P < 0.05) and comparably expressed afterwards (P > 0.05). In eyestalk-ablated broodstock, PmPTGR1 was temporally lower in early cortical rod compared to previtellogenic (I) and vitellogenic (II) ovaries (P < 0.05) and returned to the previous level in mature (IV) ovaries (P < 0.05). More importantly, the relative expression level of PmPTGR1 in each ovarian stage in eyestalk-ablated females was lower than that in intact P. monodon broodstock (P < 0.05). This strongly suggested that eyestalk ablation potentially affects the expression of PmPTGR1 allowing the stimulating effects of prostaglandins and related eicosanoids on vitellogenesis and ovarian maturation of P. monodon. The level of ovarian PmPTGR1 protein seemed to increase during ovarian development in intact broodstock but slightly reduced in mature ovaries in eyestalk-ablated broodstock. Results suggested the possible contribution of PmPTGR1 in ovarian development of P. monodon.     

Wolbachia enhance Drosophila stem cell proliferation and target the germline stem cell niche

Wolbachia are widespread maternally transmitted intracellular bacteria that infect most insect species and are able to alter the reproduction of innumerous hosts. The cellular bases of these alterations remain largely unknown. Here, we report that Drosophila mauritiana infected with a native Wolbachia wMau strain produces about four times more eggs than the noninfected counterpart. Wolbachia infection leads to an increase in the mitotic activity of germline stem cells (GSCs), as well as a decrease in programmed cell death in the germarium. Our results suggest that up-regulation of GSC division is mediated by a tropism of Wolbachia for the GSC niche, the cellular microenvironment that supports GSCs.     

A chemical switch for detecting insect infestation

BACKGROUND: Plants emit phytochemicals as a defensive mechanism against herbivores. A small sensor switch that responds to these chemicals could be used to stop insect infestation at early stages. RESULTS: Polyethylene‐co‐vinyl acetate was chosen as the best polymer for this particular application, based on its swelling response to plant volatiles. When the carbon concentration of the active layer was low enough to be near the percolation threshold, the sensor could be used as a ‘chemical switch’. The resistance of the sensor increased significantly, mimicking a ‘switch‐off’ response when exposed to the analyte vapor. When the analyte vapor was no longer present, the sensor returned back to its original condition, showing a ‘switch‐on’ response. The percolation point was obtained when the carbon concentration of the polymer/carbon composite was kept at 2.5 wt%. CONCLUSION: A low‐mass‐fraction carbon composite sensor has been designed and fabricated to detect γ‐terpinene, α‐pinene, p‐cymene, farnesene, limonene and cis‐hexenyl acetate. The sensor is inexpensive, easy to fabricate and highly stable in air. Copyright © 2011 Society of Chemical Industry     

Changes in radiation interception and R:FR over time and with canopy depth of two soybean cultivars with different branching characteristics

Because an outgrowth of auxiliary bud in plant is regulated by light quality detected by phytochrome, branching differences in various environment or cultivars in soybean would be the results of the responses to light environment. Therefore, we analyzed differences in the number of branches of two determinate soybean cultivars, ‘Hatsusayaka’ and ‘Sachiyutaka’, between low and high planting densities in relation to light quality within the canopy. We compared changes in the ratio of red to far red (R:FR) irradiance at the ground level over time and with canopy height with those in the fraction of intercepted photosynthetically active radiation (FIPAR) and leaf area index (LAI). Regardless of time or distance from the top of the canopy, the changes in R:FR were sigmoidal, and were symmetrical with those of FIPAR and LAI. The effects of density and cultivar on FIPAR, LAI, and R:FR could be modeled with a logistic function. The number of branches was greater at low density than at high density, and in Hatsusayaka than in Sachiyutaka. However, there were no notable differences in the dynamics of R:FR between planting densities or between cultivars. Close relationships between parameters of the dynamics of the changes in R:FR and of those in FIPAR and LAI suggest that FIPAR and LAI are major factors that regulate R:FR, regardless of time or canopy depth. We found no evidence of a causal relationship between the dynamics of R:FR within the canopy over time or with canopy depth and number of branches of either cultivar.