Cowpea [Vigna unguiculata (L.)] is one of the most important arid legumes cultivated for pulse and forage production. Drought is one of the most damageable constraints to crop production impacting negatively food secu...Cowpea [Vigna unguiculata (L.)] is one of the most important arid legumes cultivated for pulse and forage production. Drought is one of the most damageable constraints to crop production impacting negatively food security. The potential of cowpea to address food security is well established. However, not much is known about the base index selection method in breeding cowpea for drought tolerance, which is important for yields. Consequently, the present study has been conducted to: 1) evaluate the yield performance of cowpea genotypes under artificial drought and well-watered condition, 2) ranke genotype performance using selection indices, and 3) assess relationship between agronomic traits and yield. The experiment was the 2 watering conditions laid out in a Randomized Complete Block Design (RCBD) with three replications. The experiment was carried out in pots under screen house at the Department of Horticulture at KNUST. The result showed that KPR1-96-73, Simbo, CZ06-4-16, Wilibaly and Agyenkwa were high yielding in well-water condition while Ghana Shoba, Sangaraka, Nketewade, Ghana Shoni and Korobalen were high yielding genotypes in water stress condition. The average yield reduction was 60.6% and 16% for grain and fodder yield respectively. The biplot displays revealed four groups among the genotypes tested which were based on their yielding capacity and drought tolerance. In cluster B high yielding and drought tolerant genotypes were identified, high yielding and drought susceptible have been identified in cluster A, low yielding and drought tolerant in cluster D, and lastly low yielding and drought susceptible in cluster C. Genotypes in cluster B were best due to the fact that it combines high yield and tolerance to drought. They were Ghana Shoni, Nketewade, Sangaraka and Ghana Shoba. These genotypes might be suitably employed in further drought tolerance breeding programs of cowpea. Significant relationships were observed between agronomic trait and yields under drought condition.展开更多
The combined selection index used in the breeding of new Yorkshire dam line with high prolificacy according to breeding objects was formulated as /:2.272E- BVNB-0.056EBVDAYS. After 5 generations breeding, the two mai...The combined selection index used in the breeding of new Yorkshire dam line with high prolificacy according to breeding objects was formulated as /:2.272E- BVNB-0.056EBVDAYS. After 5 generations breeding, the two main selected traits such as total number of born and age at 100 kg weight was 12.17 piglets/litter and 165.18 d, respectively. The genetic improvements per generates was 0.156 and -2.198, respec- tively. The breeding objects of the new Yorkshire dam line with high prolificacy were basically reached. It indicated that the methods and index could be used in pig breeding.展开更多
In order to study selection indices for improving rice grain yield, a cross was made between an Iranian traditional rice (Oryza sativa L.) variety, Tarommahalli and an improved indica rice variety, Khazar in 2006. The...In order to study selection indices for improving rice grain yield, a cross was made between an Iranian traditional rice (Oryza sativa L.) variety, Tarommahalli and an improved indica rice variety, Khazar in 2006. The traits of the parents (30 plants), F1 (30 plants) and F2 generations (492 individuals) were evaluated at the Rice Research Institute of Iran (RRII) during 2007. Heritabilities of the number of panicles per plant, plant height, days to heading and panicle exsertion were greater than that of grain yield. The selection indices were developed using the results of multivariate analysis. To evaluate selection strategies to maximize grain yield, 14 selection indices were calculated based on two methods (optimum and base) and combinations of 12 traits with various economic weights. Results of selection indices showed that selection for grain weight, number of panicles per plant and panicle length by using their phenotypic and/or genotypic direct effects (path coefficient) as economic weights should serve as an effective selection criterion for using either the optimum or base index.展开更多
The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant (FY) and 15 other quantitative traits of 20 rugosa ro...The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant (FY) and 15 other quantitative traits of 20 rugosa rose cultivars. The result showed that: The grey relational grade (GRG) of the number of flowers/plant (NF), the number of branches/plant (NB), the width of floral bud (WB), and the weight/flower (WF) to the FY were larger (〉 0.5); FY improved with the increase of NF and NB. Moreover, the indirect selection of either trait could not achieve improvement of FY. It is necessary to improve FY by multi-trait selection. The integration selection index (ISI) equation of FY was established with the characters NF, NB, WB, and WF: I= 0.3187x1 - 318.6x2 + 670.1 x4 + 6.3xa, index heritability = 0.8014, selective response of the integration breeding value = 245.8811. This will provide a theoretic basis for the genetic breeding of rugosa rose.展开更多
Feature selection is one of the important topics in text classification. However, most of existing feature selection methods are serial and inefficient to be applied to massive text data sets. In this case, a feature ...Feature selection is one of the important topics in text classification. However, most of existing feature selection methods are serial and inefficient to be applied to massive text data sets. In this case, a feature selection method based on parallel collaborative evolutionary genetic algorithm is presented. The presented method uses genetic algorithm to select feature subsets and takes advantage of parallel collaborative evolution to enhance time efficiency, so it can quickly acquire the feature subsets which are more representative. The experimental results show that, for accuracy ratio and recall ratio, the presented method is better than information gain, x2 statistics, and mutual information methods; the consumed time of the presented method with only one CPU is inferior to that of these three methods, but the presented method is supe rior after using the parallel strategy.展开更多
Thirteen different inbred lines in relation to the type of grain and life cycles were characterized by testing for osmotic stress associated with salinity. The identification of tolerant genotypes would be an effectiv...Thirteen different inbred lines in relation to the type of grain and life cycles were characterized by testing for osmotic stress associated with salinity. The identification of tolerant genotypes would be an effective strategy to overcome the saline stress. Osmotic stress reduces immediately the expansion of the roots and young leaves which determine a reduction in the size of the plant. A completely randomized design was adopted to test seedlings under controlled conditions of light and temperature. Two treatments were used: 0 mM NaCl (as control) and 100 mM NaCl. After 15 days of complete salinization, the seedlings were harvested and several morphological traits were measured. The morphological traits of growth were leaf growth (Ar1, Ar2, Ar3 and Ar4), dry masses of shoot and root (SDM and RDM, respectively). Also, traits associated with water economy were registered: leaf water loss (LWL) and relative water content (RWC). The morphological traits were expressed in relative terms, while the traits associated with the economy of water were expressed in absolute terms. Uni and multivariate techniques were applied to identify genotypes with divergent behaviors to osmotic stress tolerance. Also, a Tolerance Index was employed to identify superior genotypes. Four clusters were obtained after applying a Cluster Analysis and Principal Component Analysis (PCA). The genotypes were compared to each other with a test of DMS. The results obtained with different statistical techniques converged. Some variables presented a differential weight classification of genotypes. The morphological traits like RDM, SDM, Ar3, Ar4 and Ar5 were the most discriminating. Tolerance Index allowed to classify genotypes, thus SC2 and AD3 lines were that reached highest value of the index and therefore would be tolerant lines, while AF3 and LP3 had a low index and were seen as sensible.展开更多
This study determined the indirect selection index of doubled haploid(DH)rice using a multivariate analysis approach to select lines adaptive to salinity stress,comprising three experiments.The first experiment involv...This study determined the indirect selection index of doubled haploid(DH)rice using a multivariate analysis approach to select lines adaptive to salinity stress,comprising three experiments.The first experiment involved the selection of good agronomic characters in a field experiment conducted at an experimental station in Bogor,Indonesia.The second experiment involved salinity tolerance screening through hydroponic cultures using 0 and 120 mmol/L NaCl,conducted at a greenhouse in Bogor.The third experiment involved the validation of the indirect adaptability selection index(IASI)through a field experiment in Sukra(saline area).Field experiments followed a randomized complete block design(RCBD),whereas an RCBD nested factorial design was used for the greenhouse experiment.The first and second experiments used 56 DH lines and four check varieties with three replications.In the second experiment,Pokkali and IR29 varieties were also added as tolerant and sensitive checks of salinity,respectively.The third experiment used 28 selected DH lines,Inpari 29 and one sensitive DH line.The good agronomic index(GAI)was 0.465 yield+0.433 number of productive tillers+0.31 number of filled grains.This generated 24 DH rice lines with good agronomic traits.The salinity tolerance index(SaTI)was developed through the average of standardized salinity tolerance score and salinity selection index based on discriminant analysis.This generated 34 DH rice lines with good salinity stress tolerance.The IASI(IASI=GAI–SaTI)selected 28 DH rice lines adaptive to salinity stress and it was considered effective by Sukra validation.展开更多
Maize is an important economic crop grown in Nigeria. Its production is dramatically affect by the pink stem borer--Sesamia caIamistis (Hampson, Noctuidae) and sugarcane borer--Eldana saccharina (Walker, Pyralidae...Maize is an important economic crop grown in Nigeria. Its production is dramatically affect by the pink stem borer--Sesamia caIamistis (Hampson, Noctuidae) and sugarcane borer--Eldana saccharina (Walker, Pyralidae) that are endemic in Southeastern Nigeria. In areas of stress, existing genotypes may marginally do well due to their inherent capabilities. Therefore, it is possible to find useful genes in such areas of stress, since such genes have been responsible for the survival of host crops over the years. Evaluation study was conducted for a range of agronomic characteristics and resistance attributes for 209 local maize collections from Southeastern Nigeria along with three improved check varieties. Field trials were conducted at three locations in a total of four environments in 2001. Highly significant genotypic variances as were noted in all the traits, are indicative of the magnitude of variation that exists among the genotypes, thus providing the opportunity of selection for desirable traits. Furthermore, four traits, namely, leaf feeding, ear damage, stalk lodging and yield were used from across the environments to construct a rank summation index (RSI), which was used to rank the entries for resistance to stem borers. This RSI led to the identification of 11 genotypes which represents the best 5% of the 212 genotypes in resistance ability. Genotype AMA TZBR-WC1 (from International Institute of Tropical Agriculture (IITA), Ibadan) had the best overall resistance levels, followed by genotypes SE NG-77 and SE NG-67 (from Umuahia North), SE NG-62 (from Ikwuano), SE NG-148 (from Ukwa West), SE NG-106 (from Bende), SE NG-119 (from Isiala Ngwa), SE NG-33 (from Ikwuano) and SE NG-65 (from Umuahia North).展开更多
Sugarcane family evaluation on 108 hybridized combinations generated during 2013-2014 was conducted by measuring the main traits of plant and ratoon crops. Stalk height, stalk diameter, stalk number per stool and brix...Sugarcane family evaluation on 108 hybridized combinations generated during 2013-2014 was conducted by measuring the main traits of plant and ratoon crops. Stalk height, stalk diameter, stalk number per stool and brix were investigated in both plant cane and ratoon cane, while stalk weight per stool and brix weight per stool were measured only in plant cane. Genetic variation and genetic parameters of all traits were analyzed, and the families were evaluated based on comprehensive index method. The results showed that the stalk height of both plant and ratoon, stalk diameter of both plant and ratoon, stalk number per stool of plant, brix of both plant and ratoon, stalk weight per stool and brix weight per stool were sig- nificantly different among the families. Stalk height, stalk diameter, stalk number per stool of plant crop showed higher level of broad-sense heritability, genetic variation coefficient and relative genetic advance than those in ratoon crop. But there were no significant differences in broad-sense heritability, genetic variation coefficient and relative genetic advance of brix between plant and ratoon crops. Analysis of phenotypic and genotypic correlation showed that stalk weight per stool was significantly correlated with brix weight per stool, Fifteen elite families including Zhanzhe 74-141× CP72-1210, Guitang 05-3081×Yuetang 91-976, Yunzhe 02-588×ROC22, Funong 39× Guitang 03-1229, Guitang 02-901×Guitang 03-2357, Guitang 05-2743×Guitang 03- 1229, Guitang 92-66×ROC22, Dezhe 93-88×ROC22, Guitang 05-3445×Guitang 03- 2309, Yuetang 00-319×CP72-1210, Guitang 03-3089×ROC22, Yuetang 91-976×CP84- 1198, Yuefu 90-95 ×CP72-1210, Yunzhe 99-601×Guitang 00-122, Yuetang 00-236× ROC22 were selected based on comprehensive index method, and stalk weight per stool and brix weight per stool showed greater genetic gain. The families selected based on comprehensive index were not completely the same as the families selected by brix weight per stool, the rank correlation coefficient of the families selected based on comprehensive index and brix weight per stool was 0.748 (P〈0.01).展开更多
The selection of superior genotypes based on the simultaneous response to several characteristics of agronomic importance is a key strategy to overcome the scarcity of available varieties of papaya. This study aimed t...The selection of superior genotypes based on the simultaneous response to several characteristics of agronomic importance is a key strategy to overcome the scarcity of available varieties of papaya. This study aimed to apply the combined selection by using distinct selection indexes based on both the genetic values obtained by the REML/BLUP methodology and the real measured values to select agronomically superior genotypes of papaya within backcross progenies. The combined selection was carried out based on genetic and phenotypic values, original and standardized, multiplied by the agronomic weights. The results of the analysis of genetic parameters indicate that the evaluated progenies have expressive genetic variability for the considered traits, and that there are real possibilities of genetic progress with the selection. Among the analyzed indexes, the one based on standardized genetic value presented greater consistency in the ranking of genetic material, demonstrating the advantage of data standardization. Five progenies belonging to the BC1 generation, and five to the BC3 generation were selected using this index. A total of 27 plants ag-ronomically superior were selected within the top five progenies and recommended for generation advance, 23 being selected by combined selection and 4 using the direct selection for the four mainly characters in papaya breeding program: production, pulp and fruit firmness and soluble solids. Beyond the selection of superior genotypes for the development of future inbred lines, this study also allowed defining the best strategy to apply the combined selection in papaya using pre-dicted breeding values obtained by BLUP. This strategy may allow higher accuracy in the selection process, thus increasing the chances of success of the breeding programs.展开更多
The effects of acid surface dissolution on the flotation kinetics of ilmenite(IL)and its common accompanied gangue minerals including olivine-pyroxene(Ol-Px),tremolite-clinochlore(Tr-Cch)and quartz were investigated.T...The effects of acid surface dissolution on the flotation kinetics of ilmenite(IL)and its common accompanied gangue minerals including olivine-pyroxene(Ol-Px),tremolite-clinochlore(Tr-Cch)and quartz were investigated.The results show that through the surface dissolution the adsorption rate constant for ilmenite increases from 5.272 to 8.441 mol/(g·min)while it decreases for Ol-Px,Tr-Cch and quartz from 6.332,7.309 and 7.774 mol/(g·min)to 5.034,6.223 and 7.371 mol/(g·min),respectively.Also,the flotation experiments on a binary mixture of minerals indicate that after surface dissolution the values of modified rate constant for ilmenite flotation from Ol-Px,Tr-Cch and quartz are enhanced from 36.15,36.52 and 47.86 min-1 to 41.72,45.78 and 56.24 min-1,respectively.This results in the improvement of kinetic selectivity index(SI)in the separation of treated ilmenite from gangue minerals.As evidenced by ICP-MS analysis,the decrease of kinetic parameters for gangue minerals can be due to the removal of Fe^2+,Ca^2+and Mg^2+ions from their surfaces,which results in the lack of enough active sites to interact with collector species.As confirmed by contact angle measurements,this prevents the formation of a stable hydrophobic layer on the minerals surfaces for creating stable attachments between minerals and bubbles.Generally,the improvement of ilmenite flotation kinetics has a negative correlation with the iron content in its accompanied gangue minerals.展开更多
Plant type and grain quality are two major aspects in rice breeding. Using canonical correlation analysis and canonical redundancy analysis, the relationship between plant type traits and rice grain quality traits was...Plant type and grain quality are two major aspects in rice breeding. Using canonical correlation analysis and canonical redundancy analysis, the relationship between plant type traits and rice grain quality traits was studied with 100 crosses derived from 10 sterile lines × 10 restorer lines. There was a complex relationship between parts of the traits of the two aspects. The angle of the 2nd leaf from the top and single panicle weight played important roles in plant type system and amylose content and grain length in grain quality system. The angle of the 2nd leaf from the top, plant height and single panicle weight had a great effect on grain quality traits, and amylose content, brown rice rate and translucency were easily influenced by plant type traits. Selection index model indicated that japonica hybrid rice in Northern China with good quality was characterized by broad flag leaf and 2nd leaf from the top, narrow and short 3rd leaf from the top, low plant height, short culm, long and more panicles and low single panicle weight.展开更多
A field trial of 20 seed sources of Asparagus racemosus was conducted at the Forest Research Institute, Dehradun, Uttarakhand, India to evaluate their performance of different economic traits. Genotypic variance, phen...A field trial of 20 seed sources of Asparagus racemosus was conducted at the Forest Research Institute, Dehradun, Uttarakhand, India to evaluate their performance of different economic traits. Genotypic variance, phenotypic variance, genotypic coefficient of variance (GCV) and phenotypic coefficient of variance (PCV) for number of shoots, shoot height, shoot weight, number of roots, root length, root diameter and root weight were calculated. Maximum genotypic and phenotypic variance was observed in shoot height among the shoot - related traits and root length among the root - related traits. For the shoot height, genotypic variance, phenotypic variance, genotypic coefficient of variance, phenotypic coefficient of variance were 231.80, 3924.80, 61.26 and 1037.32, respectively, where those of the root length were 9.55, 16.80, 23.46 and 41.27, respectively. The maximum genetic advance and genetic gain were obtained for shoot height among the shoot-related traits and root length among the root-related traits. Index values were developed for all the seed sources based on the four most important traits, and Panthnagar (Uttrakhand), Jodhpur (Rajasthan), Dehradun (Uttarakhand), Chandigarh (Punjab), Jammu (Jammu and Kashmir) and Solan (Himachal Pradesh), were promising seed sources for root production.展开更多
Based on the beneficial trait which is from the two component traits of feed efficiency by price, a method for drawing up selection index to improve feed efficiency is discussed. The method avoids some troubles from d...Based on the beneficial trait which is from the two component traits of feed efficiency by price, a method for drawing up selection index to improve feed efficiency is discussed. The method avoids some troubles from directly selecting feed efficiency and settles the questions to draw up selection index for the kind of ratio traits simultaneously.展开更多
Crop seeds are important sources of protein, oil, and carbohydrates for food, animal feeds, and industrial products. Recently, much attention has been paid to quality and functional properties of crop seeds. However, ...Crop seeds are important sources of protein, oil, and carbohydrates for food, animal feeds, and industrial products. Recently, much attention has been paid to quality and functional properties of crop seeds. However, seed traits possess some distinct genetic characteristics in comparison with plant traits, which increase the difficulty of genetically improving these traits. In this study, diallel analysis for seed models with genotype by environment interaction (GE) effect was applied to estimate the variance-covariance components of seed traits. Mixed linear model approaches were used to estimate the genetic covariances between pair-wise seed and plant traits. The breeding values (BV) were divided into two categories for the seed models. The first category of BV was defined as the combination of direct additive, cytoplasmic, and maternal additive effects, which should be utilized for selecting stable cultivars over multi-environments. The three genetic effects, together with their GE interaction, were included in the second category of BV for selecting special lines to be grown in specific ecosystems. Accordingly, two types of selection indices for seed traits, i.e., general selection index and interaction selection index, were developed and constructed on the first and the second category BV, respectively. These proposed selection indices can be applied to solve the difficult task of simultaneously improving multiple seed traits in various environments. Data of crop seeds with regard to four seed traits and four yield traits based on the modified diallel crosses in Upland cotton (Gossypium hirsutum L.) were used as an example for demonstrating the proposed methodology.展开更多
Introduction:As a consequence of habitat loss and degradation,the leopard cat(Prionailurus bengalensis)in China has become endangered and in need of urgent protection.In situ conservation of leopard cats must be based...Introduction:As a consequence of habitat loss and degradation,the leopard cat(Prionailurus bengalensis)in China has become endangered and in need of urgent protection.In situ conservation of leopard cats must be based on an understanding of their habitat selection patterns.We studied the summer habitat of leopard cats using line-transect surveys in the northern Taihang Mountain region surrounding Beijing,China.We compared used plots with non-used plots in elevation,tree canopy,and 20 other ecological variables,and used VanderploegScavia’s resource selection index(VSI)to analyze habitat preferences.Outcomes/others:Results show that tree canopy,tree height,tree density,and stump quantity of used plots were significantly lower than non-used plots in summer,and that leopard cats preferred habitats located on northern,flat slopes with lower slope,shrub-dominated,dry soil,and less fallen-wood.Leopard cats had a strong tendency to use habitats near human disturbance areas with moderate levels of disturbance intensity.Conclusion:The results suggest that future conservation efforts should emphasize:(1)strengthening the protection and management of forest fringe shrub habitats to improve summer habitat suitability,and(2)environmental education and animal protection campaigns to promote community biodiversity conservation.展开更多
文摘Cowpea [Vigna unguiculata (L.)] is one of the most important arid legumes cultivated for pulse and forage production. Drought is one of the most damageable constraints to crop production impacting negatively food security. The potential of cowpea to address food security is well established. However, not much is known about the base index selection method in breeding cowpea for drought tolerance, which is important for yields. Consequently, the present study has been conducted to: 1) evaluate the yield performance of cowpea genotypes under artificial drought and well-watered condition, 2) ranke genotype performance using selection indices, and 3) assess relationship between agronomic traits and yield. The experiment was the 2 watering conditions laid out in a Randomized Complete Block Design (RCBD) with three replications. The experiment was carried out in pots under screen house at the Department of Horticulture at KNUST. The result showed that KPR1-96-73, Simbo, CZ06-4-16, Wilibaly and Agyenkwa were high yielding in well-water condition while Ghana Shoba, Sangaraka, Nketewade, Ghana Shoni and Korobalen were high yielding genotypes in water stress condition. The average yield reduction was 60.6% and 16% for grain and fodder yield respectively. The biplot displays revealed four groups among the genotypes tested which were based on their yielding capacity and drought tolerance. In cluster B high yielding and drought tolerant genotypes were identified, high yielding and drought susceptible have been identified in cluster A, low yielding and drought tolerant in cluster D, and lastly low yielding and drought susceptible in cluster C. Genotypes in cluster B were best due to the fact that it combines high yield and tolerance to drought. They were Ghana Shoni, Nketewade, Sangaraka and Ghana Shoba. These genotypes might be suitably employed in further drought tolerance breeding programs of cowpea. Significant relationships were observed between agronomic trait and yields under drought condition.
基金Supported by National Science and Technology Support Plan during the Eleventh Five-year Plan(2006BAD01A08-02)Hubei Agricultural Innovation Program(2007-620-004-003)Special Fund for Modern Pig Production Technology Construction(NYCYTX-009)~~
文摘The combined selection index used in the breeding of new Yorkshire dam line with high prolificacy according to breeding objects was formulated as /:2.272E- BVNB-0.056EBVDAYS. After 5 generations breeding, the two main selected traits such as total number of born and age at 100 kg weight was 12.17 piglets/litter and 165.18 d, respectively. The genetic improvements per generates was 0.156 and -2.198, respec- tively. The breeding objects of the new Yorkshire dam line with high prolificacy were basically reached. It indicated that the methods and index could be used in pig breeding.
文摘In order to study selection indices for improving rice grain yield, a cross was made between an Iranian traditional rice (Oryza sativa L.) variety, Tarommahalli and an improved indica rice variety, Khazar in 2006. The traits of the parents (30 plants), F1 (30 plants) and F2 generations (492 individuals) were evaluated at the Rice Research Institute of Iran (RRII) during 2007. Heritabilities of the number of panicles per plant, plant height, days to heading and panicle exsertion were greater than that of grain yield. The selection indices were developed using the results of multivariate analysis. To evaluate selection strategies to maximize grain yield, 14 selection indices were calculated based on two methods (optimum and base) and combinations of 12 traits with various economic weights. Results of selection indices showed that selection for grain weight, number of panicles per plant and panicle length by using their phenotypic and/or genotypic direct effects (path coefficient) as economic weights should serve as an effective selection criterion for using either the optimum or base index.
文摘The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant (FY) and 15 other quantitative traits of 20 rugosa rose cultivars. The result showed that: The grey relational grade (GRG) of the number of flowers/plant (NF), the number of branches/plant (NB), the width of floral bud (WB), and the weight/flower (WF) to the FY were larger (〉 0.5); FY improved with the increase of NF and NB. Moreover, the indirect selection of either trait could not achieve improvement of FY. It is necessary to improve FY by multi-trait selection. The integration selection index (ISI) equation of FY was established with the characters NF, NB, WB, and WF: I= 0.3187x1 - 318.6x2 + 670.1 x4 + 6.3xa, index heritability = 0.8014, selective response of the integration breeding value = 245.8811. This will provide a theoretic basis for the genetic breeding of rugosa rose.
基金supported by the Science and Technology Plan Projects of Sichuan Province of China under Grant No.2008GZ0003the Key Technologies R & D Program of Sichuan Province of China under Grant No.2008SZ0100
文摘Feature selection is one of the important topics in text classification. However, most of existing feature selection methods are serial and inefficient to be applied to massive text data sets. In this case, a feature selection method based on parallel collaborative evolutionary genetic algorithm is presented. The presented method uses genetic algorithm to select feature subsets and takes advantage of parallel collaborative evolution to enhance time efficiency, so it can quickly acquire the feature subsets which are more representative. The experimental results show that, for accuracy ratio and recall ratio, the presented method is better than information gain, x2 statistics, and mutual information methods; the consumed time of the presented method with only one CPU is inferior to that of these three methods, but the presented method is supe rior after using the parallel strategy.
文摘Thirteen different inbred lines in relation to the type of grain and life cycles were characterized by testing for osmotic stress associated with salinity. The identification of tolerant genotypes would be an effective strategy to overcome the saline stress. Osmotic stress reduces immediately the expansion of the roots and young leaves which determine a reduction in the size of the plant. A completely randomized design was adopted to test seedlings under controlled conditions of light and temperature. Two treatments were used: 0 mM NaCl (as control) and 100 mM NaCl. After 15 days of complete salinization, the seedlings were harvested and several morphological traits were measured. The morphological traits of growth were leaf growth (Ar1, Ar2, Ar3 and Ar4), dry masses of shoot and root (SDM and RDM, respectively). Also, traits associated with water economy were registered: leaf water loss (LWL) and relative water content (RWC). The morphological traits were expressed in relative terms, while the traits associated with the economy of water were expressed in absolute terms. Uni and multivariate techniques were applied to identify genotypes with divergent behaviors to osmotic stress tolerance. Also, a Tolerance Index was employed to identify superior genotypes. Four clusters were obtained after applying a Cluster Analysis and Principal Component Analysis (PCA). The genotypes were compared to each other with a test of DMS. The results obtained with different statistical techniques converged. Some variables presented a differential weight classification of genotypes. The morphological traits like RDM, SDM, Ar3, Ar4 and Ar5 were the most discriminating. Tolerance Index allowed to classify genotypes, thus SC2 and AD3 lines were that reached highest value of the index and therefore would be tolerant lines, while AF3 and LP3 had a low index and were seen as sensible.
文摘This study determined the indirect selection index of doubled haploid(DH)rice using a multivariate analysis approach to select lines adaptive to salinity stress,comprising three experiments.The first experiment involved the selection of good agronomic characters in a field experiment conducted at an experimental station in Bogor,Indonesia.The second experiment involved salinity tolerance screening through hydroponic cultures using 0 and 120 mmol/L NaCl,conducted at a greenhouse in Bogor.The third experiment involved the validation of the indirect adaptability selection index(IASI)through a field experiment in Sukra(saline area).Field experiments followed a randomized complete block design(RCBD),whereas an RCBD nested factorial design was used for the greenhouse experiment.The first and second experiments used 56 DH lines and four check varieties with three replications.In the second experiment,Pokkali and IR29 varieties were also added as tolerant and sensitive checks of salinity,respectively.The third experiment used 28 selected DH lines,Inpari 29 and one sensitive DH line.The good agronomic index(GAI)was 0.465 yield+0.433 number of productive tillers+0.31 number of filled grains.This generated 24 DH rice lines with good agronomic traits.The salinity tolerance index(SaTI)was developed through the average of standardized salinity tolerance score and salinity selection index based on discriminant analysis.This generated 34 DH rice lines with good salinity stress tolerance.The IASI(IASI=GAI–SaTI)selected 28 DH rice lines adaptive to salinity stress and it was considered effective by Sukra validation.
文摘Maize is an important economic crop grown in Nigeria. Its production is dramatically affect by the pink stem borer--Sesamia caIamistis (Hampson, Noctuidae) and sugarcane borer--Eldana saccharina (Walker, Pyralidae) that are endemic in Southeastern Nigeria. In areas of stress, existing genotypes may marginally do well due to their inherent capabilities. Therefore, it is possible to find useful genes in such areas of stress, since such genes have been responsible for the survival of host crops over the years. Evaluation study was conducted for a range of agronomic characteristics and resistance attributes for 209 local maize collections from Southeastern Nigeria along with three improved check varieties. Field trials were conducted at three locations in a total of four environments in 2001. Highly significant genotypic variances as were noted in all the traits, are indicative of the magnitude of variation that exists among the genotypes, thus providing the opportunity of selection for desirable traits. Furthermore, four traits, namely, leaf feeding, ear damage, stalk lodging and yield were used from across the environments to construct a rank summation index (RSI), which was used to rank the entries for resistance to stem borers. This RSI led to the identification of 11 genotypes which represents the best 5% of the 212 genotypes in resistance ability. Genotype AMA TZBR-WC1 (from International Institute of Tropical Agriculture (IITA), Ibadan) had the best overall resistance levels, followed by genotypes SE NG-77 and SE NG-67 (from Umuahia North), SE NG-62 (from Ikwuano), SE NG-148 (from Ukwa West), SE NG-106 (from Bende), SE NG-119 (from Isiala Ngwa), SE NG-33 (from Ikwuano) and SE NG-65 (from Umuahia North).
基金Supported by Special Fund for Sugarcane Industry Technology System Construction(CARS-20-1-3)Scientific Research and Technological Development Program of Guangxi Zhuang Autonomous Region(1598006-1-1A)+3 种基金Special Fund for Sugarcane Breeding Program of Guangxi Zhuang Autonomous RegionSpecial Fund for Basic Scientific Research of Guangxi Academy of Agricultural Sciences(2014YZ02,2015JZ01,2015JZ02,2016YM03)Science and Technology Development Foundation of Guangxi Academy of Agricultural Sciences(2015JM05)Scientific and Technological Achievements Transformation Project of Guangxi Academy of Agricultural Sciences(2016001)~~
文摘Sugarcane family evaluation on 108 hybridized combinations generated during 2013-2014 was conducted by measuring the main traits of plant and ratoon crops. Stalk height, stalk diameter, stalk number per stool and brix were investigated in both plant cane and ratoon cane, while stalk weight per stool and brix weight per stool were measured only in plant cane. Genetic variation and genetic parameters of all traits were analyzed, and the families were evaluated based on comprehensive index method. The results showed that the stalk height of both plant and ratoon, stalk diameter of both plant and ratoon, stalk number per stool of plant, brix of both plant and ratoon, stalk weight per stool and brix weight per stool were sig- nificantly different among the families. Stalk height, stalk diameter, stalk number per stool of plant crop showed higher level of broad-sense heritability, genetic variation coefficient and relative genetic advance than those in ratoon crop. But there were no significant differences in broad-sense heritability, genetic variation coefficient and relative genetic advance of brix between plant and ratoon crops. Analysis of phenotypic and genotypic correlation showed that stalk weight per stool was significantly correlated with brix weight per stool, Fifteen elite families including Zhanzhe 74-141× CP72-1210, Guitang 05-3081×Yuetang 91-976, Yunzhe 02-588×ROC22, Funong 39× Guitang 03-1229, Guitang 02-901×Guitang 03-2357, Guitang 05-2743×Guitang 03- 1229, Guitang 92-66×ROC22, Dezhe 93-88×ROC22, Guitang 05-3445×Guitang 03- 2309, Yuetang 00-319×CP72-1210, Guitang 03-3089×ROC22, Yuetang 91-976×CP84- 1198, Yuefu 90-95 ×CP72-1210, Yunzhe 99-601×Guitang 00-122, Yuetang 00-236× ROC22 were selected based on comprehensive index method, and stalk weight per stool and brix weight per stool showed greater genetic gain. The families selected based on comprehensive index were not completely the same as the families selected by brix weight per stool, the rank correlation coefficient of the families selected based on comprehensive index and brix weight per stool was 0.748 (P〈0.01).
基金the Fundacao de Amparo a Pesquisa do Estado do Rio de Janeiro(FAPERJ)for providing the Master’s scholarshipthe Empresa Caliman Agrícola S/A(Caliman)for the financial and logistical support.
文摘The selection of superior genotypes based on the simultaneous response to several characteristics of agronomic importance is a key strategy to overcome the scarcity of available varieties of papaya. This study aimed to apply the combined selection by using distinct selection indexes based on both the genetic values obtained by the REML/BLUP methodology and the real measured values to select agronomically superior genotypes of papaya within backcross progenies. The combined selection was carried out based on genetic and phenotypic values, original and standardized, multiplied by the agronomic weights. The results of the analysis of genetic parameters indicate that the evaluated progenies have expressive genetic variability for the considered traits, and that there are real possibilities of genetic progress with the selection. Among the analyzed indexes, the one based on standardized genetic value presented greater consistency in the ranking of genetic material, demonstrating the advantage of data standardization. Five progenies belonging to the BC1 generation, and five to the BC3 generation were selected using this index. A total of 27 plants ag-ronomically superior were selected within the top five progenies and recommended for generation advance, 23 being selected by combined selection and 4 using the direct selection for the four mainly characters in papaya breeding program: production, pulp and fruit firmness and soluble solids. Beyond the selection of superior genotypes for the development of future inbred lines, this study also allowed defining the best strategy to apply the combined selection in papaya using pre-dicted breeding values obtained by BLUP. This strategy may allow higher accuracy in the selection process, thus increasing the chances of success of the breeding programs.
文摘The effects of acid surface dissolution on the flotation kinetics of ilmenite(IL)and its common accompanied gangue minerals including olivine-pyroxene(Ol-Px),tremolite-clinochlore(Tr-Cch)and quartz were investigated.The results show that through the surface dissolution the adsorption rate constant for ilmenite increases from 5.272 to 8.441 mol/(g·min)while it decreases for Ol-Px,Tr-Cch and quartz from 6.332,7.309 and 7.774 mol/(g·min)to 5.034,6.223 and 7.371 mol/(g·min),respectively.Also,the flotation experiments on a binary mixture of minerals indicate that after surface dissolution the values of modified rate constant for ilmenite flotation from Ol-Px,Tr-Cch and quartz are enhanced from 36.15,36.52 and 47.86 min-1 to 41.72,45.78 and 56.24 min-1,respectively.This results in the improvement of kinetic selectivity index(SI)in the separation of treated ilmenite from gangue minerals.As evidenced by ICP-MS analysis,the decrease of kinetic parameters for gangue minerals can be due to the removal of Fe^2+,Ca^2+and Mg^2+ions from their surfaces,which results in the lack of enough active sites to interact with collector species.As confirmed by contact angle measurements,this prevents the formation of a stable hydrophobic layer on the minerals surfaces for creating stable attachments between minerals and bubbles.Generally,the improvement of ilmenite flotation kinetics has a negative correlation with the iron content in its accompanied gangue minerals.
文摘Plant type and grain quality are two major aspects in rice breeding. Using canonical correlation analysis and canonical redundancy analysis, the relationship between plant type traits and rice grain quality traits was studied with 100 crosses derived from 10 sterile lines × 10 restorer lines. There was a complex relationship between parts of the traits of the two aspects. The angle of the 2nd leaf from the top and single panicle weight played important roles in plant type system and amylose content and grain length in grain quality system. The angle of the 2nd leaf from the top, plant height and single panicle weight had a great effect on grain quality traits, and amylose content, brown rice rate and translucency were easily influenced by plant type traits. Selection index model indicated that japonica hybrid rice in Northern China with good quality was characterized by broad flag leaf and 2nd leaf from the top, narrow and short 3rd leaf from the top, low plant height, short culm, long and more panicles and low single panicle weight.
文摘A field trial of 20 seed sources of Asparagus racemosus was conducted at the Forest Research Institute, Dehradun, Uttarakhand, India to evaluate their performance of different economic traits. Genotypic variance, phenotypic variance, genotypic coefficient of variance (GCV) and phenotypic coefficient of variance (PCV) for number of shoots, shoot height, shoot weight, number of roots, root length, root diameter and root weight were calculated. Maximum genotypic and phenotypic variance was observed in shoot height among the shoot - related traits and root length among the root - related traits. For the shoot height, genotypic variance, phenotypic variance, genotypic coefficient of variance, phenotypic coefficient of variance were 231.80, 3924.80, 61.26 and 1037.32, respectively, where those of the root length were 9.55, 16.80, 23.46 and 41.27, respectively. The maximum genetic advance and genetic gain were obtained for shoot height among the shoot-related traits and root length among the root-related traits. Index values were developed for all the seed sources based on the four most important traits, and Panthnagar (Uttrakhand), Jodhpur (Rajasthan), Dehradun (Uttarakhand), Chandigarh (Punjab), Jammu (Jammu and Kashmir) and Solan (Himachal Pradesh), were promising seed sources for root production.
文摘Based on the beneficial trait which is from the two component traits of feed efficiency by price, a method for drawing up selection index to improve feed efficiency is discussed. The method avoids some troubles from directly selecting feed efficiency and settles the questions to draw up selection index for the kind of ratio traits simultaneously.
基金supported by the National Basic Research Program of China (No. 2006CB101708)National Science and Technology Supporting Item of China (No. 2006BAD10A00).
文摘Crop seeds are important sources of protein, oil, and carbohydrates for food, animal feeds, and industrial products. Recently, much attention has been paid to quality and functional properties of crop seeds. However, seed traits possess some distinct genetic characteristics in comparison with plant traits, which increase the difficulty of genetically improving these traits. In this study, diallel analysis for seed models with genotype by environment interaction (GE) effect was applied to estimate the variance-covariance components of seed traits. Mixed linear model approaches were used to estimate the genetic covariances between pair-wise seed and plant traits. The breeding values (BV) were divided into two categories for the seed models. The first category of BV was defined as the combination of direct additive, cytoplasmic, and maternal additive effects, which should be utilized for selecting stable cultivars over multi-environments. The three genetic effects, together with their GE interaction, were included in the second category of BV for selecting special lines to be grown in specific ecosystems. Accordingly, two types of selection indices for seed traits, i.e., general selection index and interaction selection index, were developed and constructed on the first and the second category BV, respectively. These proposed selection indices can be applied to solve the difficult task of simultaneously improving multiple seed traits in various environments. Data of crop seeds with regard to four seed traits and four yield traits based on the modified diallel crosses in Upland cotton (Gossypium hirsutum L.) were used as an example for demonstrating the proposed methodology.
基金This research was supported by The Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment,China(2019HJ2096001006)the Nature Science Foundation of China(31672300).
文摘Introduction:As a consequence of habitat loss and degradation,the leopard cat(Prionailurus bengalensis)in China has become endangered and in need of urgent protection.In situ conservation of leopard cats must be based on an understanding of their habitat selection patterns.We studied the summer habitat of leopard cats using line-transect surveys in the northern Taihang Mountain region surrounding Beijing,China.We compared used plots with non-used plots in elevation,tree canopy,and 20 other ecological variables,and used VanderploegScavia’s resource selection index(VSI)to analyze habitat preferences.Outcomes/others:Results show that tree canopy,tree height,tree density,and stump quantity of used plots were significantly lower than non-used plots in summer,and that leopard cats preferred habitats located on northern,flat slopes with lower slope,shrub-dominated,dry soil,and less fallen-wood.Leopard cats had a strong tendency to use habitats near human disturbance areas with moderate levels of disturbance intensity.Conclusion:The results suggest that future conservation efforts should emphasize:(1)strengthening the protection and management of forest fringe shrub habitats to improve summer habitat suitability,and(2)environmental education and animal protection campaigns to promote community biodiversity conservation.