In Wireless Sensor Networks(WSNs),Clustering process is widely utilized for increasing the lifespan with sustained energy stability during data transmission.Several clustering protocols were devised for extending netw...In Wireless Sensor Networks(WSNs),Clustering process is widely utilized for increasing the lifespan with sustained energy stability during data transmission.Several clustering protocols were devised for extending network lifetime,but most of them failed in handling the problem of fixed clustering,static rounds,and inadequate Cluster Head(CH)selection criteria which consumes more energy.In this paper,Stochastic Ranking Improved Teaching-Learning and Adaptive Grasshopper Optimization Algorithm(SRITL-AGOA)-based Clustering Scheme for energy stabilization and extending network lifespan.This SRITL-AGOA selected CH depending on the weightage of factors such as node mobility degree,neighbour's density distance to sink,single-hop or multihop communication and Residual Energy(RE)that directly influences the energy consumption of sensor nodes.In specific,Grasshopper Optimization Algorithm(GOA)is improved through tangent-based nonlinear strategy for enhancing the ability of global optimization.On the other hand,stochastic ranking and violation constraint handling strategies are embedded into Teaching-Learning-based Optimization Algorithm(TLOA)for improving its exploitation tendencies.Then,SR and VCH improved TLOA is embedded into the exploitation phase of AGOA for selecting better CH by maintaining better balance amid exploration and exploitation.Simulation results confirmed that the proposed SRITL-AGOA improved throughput by 21.86%,network stability by 18.94%,load balancing by 16.14%with minimized energy depletion by19.21%,compared to the competitive CH selection approaches.展开更多
This study assessed the effect of cyanogenic potential (CNP) in leaf tissue on grasshopper incidence and severity of damage in cassava for the identification of parents with desired complementary traits for crossing. T...This study assessed the effect of cyanogenic potential (CNP) in leaf tissue on grasshopper incidence and severity of damage in cassava for the identification of parents with desired complementary traits for crossing. The experiment was conducted at the Foya Wulleh, Njala experimental site in Sierra Leone during 2020 and 2021 cropping seasons in a randomized complete block design with three replications. A total of 30 genotypes comprising 26 breeding lines, two improved and two local genotypes were assessed. Results showed a significant (p < 0.05) linear relationship between leaf CNP and grasshopper infestation (incidence and severity of damage) among cassava genotypes. Findings showed that the higher leaf CNP, the lower the grasshopper infestation in cassava genotypes. About two genotypes (Cooksoon and Cocoa) had low leaf CNP;three genotypes (TR0020, TR0037 and TR0013) CNP had moderately low leaf CNP;eight genotypes (SLICASS 6, TR0029, TR0032, TR0011, TR0012, TR0016-1/17, TR0002 and TR0010) had intermediate leaf CNP;seven (TR0009, TR0015-1/17, TR0036, TR0022-1/17, SLICASS 4, TR0007 and TR0026-1/17) had moderately high leaf CNP;eight (TR0008, TR0019-1/17, TR0006, TR0005, TR0021, TR0021-1/17, TR0022 and TR0024-1/17) had high leaf CNP;and two genotypes (TR0001 and TR0018-1/17) had very high leaf CNP. This suggests the indirect dependence of leaf cyanogenic potential on grasshopper infestation (incidence and severity of damage) in cassava that could be exploited for the genetic improvement of cassava for improved resistance to grasshopper infestation, nutrition and utilization of the crop.展开更多
Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for ha...Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus L.) reared some cassava (Manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra Leone during 2022/2023. The treatments comprised three soil types (Sandy, Loamy and Clay), each with three replications laid out in a randomized complete block design (RCBD) in wooden cages. Data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), Doubling time (Dt), and overall survivorship. Findings revealed that, Z. variegatus L. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.展开更多
[ Objective] The relationship between the genetic evolution and phylogenesis of the main grasshopper species in Inner Mongolia grasslands in molecular level was studied. [ Method] Random amplified polymorphic DNA （R...[ Objective] The relationship between the genetic evolution and phylogenesis of the main grasshopper species in Inner Mongolia grasslands in molecular level was studied. [ Method] Random amplified polymorphic DNA （RAPD） technique was used to amplify the 80 individuals of 8 grasshoppers （4 families, 6 genera） in Acridoidea, the polymorphisms of their genomic DNA were compared. [ Result] 64 specific fragments were amplified by 7 primers with the molecular weight of 300 -2 000 bp. The genetic distance between 8 grasshoppers was 0.228 2 -0.589 6. Band pat- tern showed that polymorphism was commonly existed in different genus within the same family and different species within the same genus. The resuits were conducted UPGMA cluster analysis according to Neis＇ genetic distance, the results showed that the species within the same genus first clustered together, then the species in the same family clustered together. [ Condusloa] The study could provide molecular biological basis for system development and evolution research of main grasshoppers in Inner Mongolia grassland.展开更多
The grassland in western Heilongiiang basically belongs to mesophytic meadow grassland with more than 103 species of grasses, while Leymus chinensis meadow grassland and L. chinensis herbage steppe have the largest di...The grassland in western Heilongiiang basically belongs to mesophytic meadow grassland with more than 103 species of grasses, while Leymus chinensis meadow grassland and L. chinensis herbage steppe have the largest distribution. L. chinensis, ArundineUa hirta （ Thunb. ） C. Tanaka, Gleistogenes chinensis （ Max- im. ） Keng, Stipa baicalensis Roshev, Carex tristachya, Deyeuxia langsdorffii （Link） Kunth, Artemisia integrifolia, Carex meyeriana and Cyperus rotundus are the main dominant and subdominant species. There are about 17 common species of grasshoppers causing damage on grassland, while eight of them are dominant spe- cies. According to the characters of grassland, vegetation and the species of grasshoppers, the paper has raised the integrated control measures for grasshoppers in western Heilongjiang.展开更多
文摘In Wireless Sensor Networks(WSNs),Clustering process is widely utilized for increasing the lifespan with sustained energy stability during data transmission.Several clustering protocols were devised for extending network lifetime,but most of them failed in handling the problem of fixed clustering,static rounds,and inadequate Cluster Head(CH)selection criteria which consumes more energy.In this paper,Stochastic Ranking Improved Teaching-Learning and Adaptive Grasshopper Optimization Algorithm(SRITL-AGOA)-based Clustering Scheme for energy stabilization and extending network lifespan.This SRITL-AGOA selected CH depending on the weightage of factors such as node mobility degree,neighbour's density distance to sink,single-hop or multihop communication and Residual Energy(RE)that directly influences the energy consumption of sensor nodes.In specific,Grasshopper Optimization Algorithm(GOA)is improved through tangent-based nonlinear strategy for enhancing the ability of global optimization.On the other hand,stochastic ranking and violation constraint handling strategies are embedded into Teaching-Learning-based Optimization Algorithm(TLOA)for improving its exploitation tendencies.Then,SR and VCH improved TLOA is embedded into the exploitation phase of AGOA for selecting better CH by maintaining better balance amid exploration and exploitation.Simulation results confirmed that the proposed SRITL-AGOA improved throughput by 21.86%,network stability by 18.94%,load balancing by 16.14%with minimized energy depletion by19.21%,compared to the competitive CH selection approaches.
文摘This study assessed the effect of cyanogenic potential (CNP) in leaf tissue on grasshopper incidence and severity of damage in cassava for the identification of parents with desired complementary traits for crossing. The experiment was conducted at the Foya Wulleh, Njala experimental site in Sierra Leone during 2020 and 2021 cropping seasons in a randomized complete block design with three replications. A total of 30 genotypes comprising 26 breeding lines, two improved and two local genotypes were assessed. Results showed a significant (p < 0.05) linear relationship between leaf CNP and grasshopper infestation (incidence and severity of damage) among cassava genotypes. Findings showed that the higher leaf CNP, the lower the grasshopper infestation in cassava genotypes. About two genotypes (Cooksoon and Cocoa) had low leaf CNP;three genotypes (TR0020, TR0037 and TR0013) CNP had moderately low leaf CNP;eight genotypes (SLICASS 6, TR0029, TR0032, TR0011, TR0012, TR0016-1/17, TR0002 and TR0010) had intermediate leaf CNP;seven (TR0009, TR0015-1/17, TR0036, TR0022-1/17, SLICASS 4, TR0007 and TR0026-1/17) had moderately high leaf CNP;eight (TR0008, TR0019-1/17, TR0006, TR0005, TR0021, TR0021-1/17, TR0022 and TR0024-1/17) had high leaf CNP;and two genotypes (TR0001 and TR0018-1/17) had very high leaf CNP. This suggests the indirect dependence of leaf cyanogenic potential on grasshopper infestation (incidence and severity of damage) in cassava that could be exploited for the genetic improvement of cassava for improved resistance to grasshopper infestation, nutrition and utilization of the crop.
文摘Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus L.) reared some cassava (Manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra Leone during 2022/2023. The treatments comprised three soil types (Sandy, Loamy and Clay), each with three replications laid out in a randomized complete block design (RCBD) in wooden cages. Data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), Doubling time (Dt), and overall survivorship. Findings revealed that, Z. variegatus L. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.
基金Supported by Basic Scientific Research Fund Project of Nonprofit Research Institutions(Grassland Research Institute,Chinese Academy of Agricultural Sciences)~~
文摘[ Objective] The relationship between the genetic evolution and phylogenesis of the main grasshopper species in Inner Mongolia grasslands in molecular level was studied. [ Method] Random amplified polymorphic DNA （RAPD） technique was used to amplify the 80 individuals of 8 grasshoppers （4 families, 6 genera） in Acridoidea, the polymorphisms of their genomic DNA were compared. [ Result] 64 specific fragments were amplified by 7 primers with the molecular weight of 300 -2 000 bp. The genetic distance between 8 grasshoppers was 0.228 2 -0.589 6. Band pat- tern showed that polymorphism was commonly existed in different genus within the same family and different species within the same genus. The resuits were conducted UPGMA cluster analysis according to Neis＇ genetic distance, the results showed that the species within the same genus first clustered together, then the species in the same family clustered together. [ Condusloa] The study could provide molecular biological basis for system development and evolution research of main grasshoppers in Inner Mongolia grassland.
基金Supported by Natural Science Foundation of Heilongjiang Province (C9833)~~
文摘The grassland in western Heilongiiang basically belongs to mesophytic meadow grassland with more than 103 species of grasses, while Leymus chinensis meadow grassland and L. chinensis herbage steppe have the largest distribution. L. chinensis, ArundineUa hirta （ Thunb. ） C. Tanaka, Gleistogenes chinensis （ Max- im. ） Keng, Stipa baicalensis Roshev, Carex tristachya, Deyeuxia langsdorffii （Link） Kunth, Artemisia integrifolia, Carex meyeriana and Cyperus rotundus are the main dominant and subdominant species. There are about 17 common species of grasshoppers causing damage on grassland, while eight of them are dominant spe- cies. According to the characters of grassland, vegetation and the species of grasshoppers, the paper has raised the integrated control measures for grasshoppers in western Heilongjiang.
