Genetic algorithms for the sequential irrigation scheduling problem

A sequential irrigation scheduling problem is the problem of preparing a schedule to sequentially service a set of water users. This problem has an analogy with the classical single machine earliness/tardiness scheduling problem in operations research. In previously published work, integer program and heuristics were used to solve sequential irrigation scheduling problems; however, such scheduling problems belong to a class of combinatorial optimization problems known to be computationally demanding (NP-hard). This is widely reported in operations research. Hence, integer program can only be used to solve relatively small problems usually in a research environment where considerable computational resources and time can be allocated to solve a single schedule. For practical applications, metaheuristics such as genetic algorithms (GA), simulated annealing, or tabu search methods need to be used. These need to be formulated carefully and tested thoroughly. The current research is to explore the potential of GA to solve the sequential irrigation scheduling problems. Four GA models are presented that model four different sequential irrigation scenarios. The GA models are tested extensively for a range of problem sizes, and the solution quality is compared against solutions from integer programs and heuristics. The GA is applied to the practical engineering problem of scheduling water scheduling to 94 water users.     

Managing salinity and waterlogging in the Indus Basin of Pakistan

Waterlogging and salinization are major impediment to the sustainability of irrigated lands and livelihoods of the farmers, especially the smallholders, in the affected areas of the Indus Basin. These problems are the result of a multitude of factors, including seepage from unlined earthen canals system, inadequate provision of surface and subsurface drainage, poor water management practices, insufficient water supplies and use of poor quality groundwater for irrigation. About 6.3 million ha are affected by different levels and types of salinity, out of which nearly half are under irrigated agriculture. Since the early 1960s, several efforts have been made to improve the management of salt-affected and waterlogged soils. These include lowering groundwater levels through deep tubewells, leaching of salts by excess irrigation, application of chemical amendments (e.g. gypsum, acids, organic matter), and the use of biological and physical methods. However, in spite of huge investments, the results have in general been disappointing and the problems of waterlogging and salinity persist.This paper reviews sources, causes and extent of salinity and waterlogging problems in the Indus Basin. Measures taken to overcome these problems over the last four decades are also discussed. The results reveal that the installed drainage systems were initially successful in lowering groundwater table and reducing salinity in affected areas. However, poor operation and maintenance of these systems and provision of inadequate facilities for the disposal of saline drainage effluent resulted in limited overall success. The paper suggests that to ensure the sustainability of irrigated agriculture in the Indus Basin, technical and financial support is needed and enhanced institutional arrangements including coordination among different federal and provincial government agencies to resolve inter-provincial water allocation and water related issues is required.     

Gene flow from transgenic wheat and barley under field conditions

In this study the frequency and distance of gene flow from transgenic wheat (Triticum aestivum) and barley (Hordeum vulgare) to non-transgenic wheat and barley crops was investigated under local field conditions. Trials were conducted in the Australian Capital Territory (ACT) and in South Australia (SA). Gene flow from transgenic wheat was confirmed at frequencies of 0.012% and 0.0037% in the ACT and SA, respectively. In both trials gene flow occurred over distances of less than 12 m. Gene flow was also detected from transgenic barley at a frequency of 0.005%, over a distance of less than 12 m. The results show that under Australian field conditions, gene flow occurs at extremely low frequencies and over very short distances. Physical separation of transgenic and non-transgenic cereal crops by greater than 12 m should ensure that contamination of adjacent non-transgenic cereal crops remains less than 0.02%, well below the level permitted under Australian regulations.     

Nitrogen transformation and carbon sequestration in wetland paddy field of Bangladesh

Paddy and Water Environment - Rice-based cropping systems in Bangladesh have received little consideration of changing nitrogen (N) and carbon (C) in soil. Therefore, this study was conducted at...     

Pheromone trap catches as a means of predicting damage by pink bollworm larvae in cotton

The male moth catches in gossyplure-baited traps were used to predict larval infestation of pink bollworm, Pectinophora gossypiella (Saunders), in cotton fields during 1988 and 1989. The mean moth catches per trap per night were positively correlated with percentage larval infestation. The moth counts in traps and larval infestation in green bolls increased with advance in reproductive stage of the cotton plants. A mean trap catch of 9–12 pink bollworm moths per night was associated with economically damaging infestation. It is, therefore, inferred that insecticidal sprays may be scheduled when 9–12 moths are captured per trap per night.     

Vesicular glutamate transporters 1 and 2 target to functionally distinct synaptic release sites

Vesicular glutamate transporters (VGLUTs) 1 and 2 show a mutually exclusive distribution in the adult brain that suggests specialization for synapses with different properties of release. Consistent with this distribution, inactivation of the VGLUT1 gene silenced a subset of excitatory neurons in the adult. However, the same cell populations exhibited VGLUT1-independent transmission early in life. Developing hippocampal neurons transiently coexpressed VGLUT2 and VGLUT1 at distinct synaptic sites with different short-term plasticity. The loss of VGLUT1 also reduced the reserve pool of synaptic vesicles. Thus, VGLUT1 plays an unanticipated role in membrane trafficking at the nerve terminal.     

Prevalence and Characterization of Coagulase Positive Staphylococci Isolated from Salted Anchovy

A total of 100 salted anchovy samples were used to investigate the prevalence of S. aureus and other coagulase positive Staphylococci (CPS) as well as to determine the methicillin (MR) and antibiotic resistance (AR) profile, the presence of Panton-Valentine leukocidine (PVL) toxin gene (lukS/F-PV), slime factor properties (SFP), and the genotypic relatedness of the isolates. Agar disc diffusion assay (ADDA) and microdilution broth susceptibility test (MDBST) were applied to compare the specificity and sensitivity of the MR detection methods. A total of 41 CPS isolates were detected at the 10² and 10³ CFU/g levels in contrast to S. aureus. The 16S rRNA (genus specific) was detected in all the isolates in contrast to nuc (species-specific) and lukS/F-PV genes. A total of 16/41 isolates were found to be MR by using the three methods. Polymerase chain reaction (PCR) assay was a more sensitive and reliable method for the detection of MR isolates. The antibiotic resistance rates were 75.60, 73.17, 51.21, 31.70, 12.19, and 4.87% to penicillin, ampicillin, tetracycline, erythromycin, ciprofloxacin, and clindamycin, respectively. All the isolates were sensitive to gentamicin and vancomycin. The SFP were determined in all the isolates by using Congo Red agar, and 20 different genotypes were determined by using randomly amplified polymorphic DNA (RAPD)-PCR assay.     

Seed priming improves early seedling vigor,growth and productivity of spring maize

Potential of seed priming treatments in improving the performance of early planted maize was evaluated against timely planting. Seeds of maize hybrid FH-810 were soaked in water(hydropriming), Ca Cl2(2.2%, osmopriming), moringa leaf extracts(MLE 3.3%, osmopriming) and salicylic acid(SA, 50 mg L–1, hormonal priming) each for 18 h. Untreated and hydroprimed seeds were taken as control. Seeds primed with SA took less time in emergence and had high vigor in early planted maize. Amongst treatments, hormonal priming, reduced the electrical conductivity, increased the leaf relative and chlorophyll contents followed by osmopriming with Ca Cl2 at seedling stage. Likewise, plant height, grain rows and 1 000-grain weight, grain and biological yield and harvest index were also improved by seed priming; however hormonal priming and osmopriming with MLE were more effective in this regard. Improved yield performance by hormonal priming or osmopriming with MLE in early planting primarily owed to increased leaf area index, crop growth and net assimilation rates, and maintenance of green leaf area at maturity. In conclusion, osmopriming with MLE and hormonal priming with SA were the most economical treatments in improving productivity of early planted spring maize through stimulation of early seedling growth at low temperature.     

Different Eucalyptus Species Show Different Mechanisms of Tolerance to Salinity and Salinity × Hypoxia

ABSTRACT

We studied the effect of sodium chloride (NaCl) salinity and oxygen deficiency stress on growth and leaf ionic composition of three Eucalyptus species [E. tereticornis, E. camaldulensis (Silverton), and E. camaldulensis (Local)]. Species were grown with control (no NaCl) and salinity (150 mol m^?3 NaCl) under hypoxic and non-hypoxic conditions in nutrient solution with five replications following CRD. Species differed significantly in their response to salinity and hypoxia. Absolute shoot dry matter was significantly better in E. camaldulensis (Silverton) in salinity and in E. camaldulensis (Local) in saline hypoxic treatment. E. tereticornis was the most sensitive species to salinity and salinity × hypoxia in the root environment. Sodium (Na⁺) and chloride (Cl^?) concentrations were significantly lower in E. camaldulensis (Local) in non-hypoxic saline treatment compared to the other two species. E. camaldulensis (Silverton) seems to have better tissue compartmentalization, whereas E. camaldulensis (local) seems to have better exclusion of Na⁺ at the root level.     

Isolation and identification of novel tocotrienols from rice bran with hypocholesterolemic, antioxidant, and antitumor properties

Two novel tocotrienols were isolated from stabilized and heated rice bran, apart from the known alpha-, beta-, gamma-, and delta-tocopherols and tocotrienols. These new tocotrienols were separated by HPLC, using a normal phase silica column. Their structures were determined by ultraviolet, infrared, nuclear magnetic resonance, circular dichroism, and high-resolution mass spectroscopies and established as desmethyl tocotrienol [3, 4-dihydro-2-methyl-2-(4,8,12-trimethyltrideca-3'(E),7'(E), 11'-trienyl)-2H-1-benzopyran-6-ol] and didesmethy tocotrienol [3, 4-dihydro-2-(4,8,12-trimethyltrideca-3'(E),7'(E), 11'-trienyl)-2H-1-benzopyran-6-ol]. These tocotrienols significantly lowered serum total and LDL cholesterol levels and inhibited HMG-CoA reductase activity in chickens. They had much greater in vitro antioxidant activities and greater suppression of B16 melanoma cell proliferation than alpha-tocopherol and known tocotrienols. Results indicated that the number and position of methyl substituents in tocotrienols affect their hypocholesterolemic, antioxidant, and antitumor properties.