利用小麦条锈病品种-小种群体间相互关系模型即大区流行模型,PANCRIN,进行了模拟试验。模拟试验结果导致了如下推测或假想,如;1.陇南半山麦田的自生麦苗在大区流行中作用最大,但大区流行周年循环除冬麦和春麦→自生苗→冬麦这一主要路线...利用小麦条锈病品种-小种群体间相互关系模型即大区流行模型,PANCRIN,进行了模拟试验。模拟试验结果导致了如下推测或假想,如;1.陇南半山麦田的自生麦苗在大区流行中作用最大,但大区流行周年循环除冬麦和春麦→自生苗→冬麦这一主要路线外,可能还有一条冬麦→晚熟春麦→早播冬麦的次要路线。2.陇冬早播冬麦区在大区流行秋季菌源传播中的桥梁作用虽可肯定,但陇南 L2、L3自生苗上的菌源对关中、黄淮、江淮麦区 L7、L8、L9的作用仍然很大。3.消灭自生麦苗,必需把密度消减到历史最大密度的10%才能明显见效。4.不论新小种产生的突变率 MU 大小,全大区范围的品种布局比局布地区的,对延长广大平原麦区的品种抗病性更为有效;等等。这些结果一部分与已有经验或看法基本符合,另一部分则可为未知问题和有争议的问题的研究解决提供参考。展开更多
为适应品种一小种间群体上相互关系和新小种流行预测等问题定量研究的需要,提出了植物病原物寄生适合度(F)两种操作定义和相应两种测定方法。方法Ⅰ可称为相对1代病情法,方法Ⅱ可称为相对表观侵染速率法,前者适用于按病菌每代繁殖倍数...为适应品种一小种间群体上相互关系和新小种流行预测等问题定量研究的需要,提出了植物病原物寄生适合度(F)两种操作定义和相应两种测定方法。方法Ⅰ可称为相对1代病情法,方法Ⅱ可称为相对表观侵染速率法,前者适用于按病菌每代繁殖倍数进行运算的模型,后者适用于按逻辑斯蒂模型进行运算的模型,两法所得 F 值可以相互换算。初步设计了符合操作定义的田间试验方法,用相应试验所得数据可算出 F 值。根据作者用第一手实测数据估算两种 F 值的经验,认为两种 F 值在测定和应用上互有优劣,可因地制宜采用,但均需作好数据资料测定的试验设计,使之符合操作定义的要求,并精心执行、力求缩小试验误差,以使所得 F 值能有实用价值。展开更多
The 5.12 Earthquake in 2008 and 8.14 Debris Flow in 2010 resulted in large-scale landslides that disturbed vast areas of vegetation in the Hongchun Gully, Wenchuan County, China. To define the specific characteristics...The 5.12 Earthquake in 2008 and 8.14 Debris Flow in 2010 resulted in large-scale landslides that disturbed vast areas of vegetation in the Hongchun Gully, Wenchuan County, China. To define the specific characteristics of vegetation restoration during natural recovery after catastrophic events,vegetation species composition and interspecific associations were investigated on this typical landslide. Field survey data selected from a total of 51 sample plots belonged to seven belt transects and were analysed by Schluter's variance ratio, pearson's chi-squared test, Spearman's correlation coefficients and ecological species groups. Plant communities on the landslide consisted of 78 species, 65 genera and52 families. Of the total of 78 species, 25 are identified as dominant species, among which Camptotheca acuminate, Toxicodendron vernicifluum, Coriaria nepalensis, Robinia pseudoacacia, Buddleja alternifolia, Anemone vitifolia and Nephrolepis auriculata play a constructive role during the natural afforestation. Moreover, according to environmental and ecological factors, these 25 dominant species could be divided into four ecological species groups.This study found that even though the landslide had frequently suffered from interference due to heavy rain, the vegetation succession processes are ongoing,and it is now at a shrub–herb community succession stage, which indicates that vegetation can naturally recover in the denuded sites. This study provides a useful insight into the ecological interactions and interdependence between plant species during the natural recovery of vegetation and provides valuable information on vegetation recovery modelling in the landslide area.展开更多
文摘利用小麦条锈病品种-小种群体间相互关系模型即大区流行模型,PANCRIN,进行了模拟试验。模拟试验结果导致了如下推测或假想,如;1.陇南半山麦田的自生麦苗在大区流行中作用最大,但大区流行周年循环除冬麦和春麦→自生苗→冬麦这一主要路线外,可能还有一条冬麦→晚熟春麦→早播冬麦的次要路线。2.陇冬早播冬麦区在大区流行秋季菌源传播中的桥梁作用虽可肯定,但陇南 L2、L3自生苗上的菌源对关中、黄淮、江淮麦区 L7、L8、L9的作用仍然很大。3.消灭自生麦苗,必需把密度消减到历史最大密度的10%才能明显见效。4.不论新小种产生的突变率 MU 大小,全大区范围的品种布局比局布地区的,对延长广大平原麦区的品种抗病性更为有效;等等。这些结果一部分与已有经验或看法基本符合,另一部分则可为未知问题和有争议的问题的研究解决提供参考。
文摘为适应品种一小种间群体上相互关系和新小种流行预测等问题定量研究的需要,提出了植物病原物寄生适合度(F)两种操作定义和相应两种测定方法。方法Ⅰ可称为相对1代病情法,方法Ⅱ可称为相对表观侵染速率法,前者适用于按病菌每代繁殖倍数进行运算的模型,后者适用于按逻辑斯蒂模型进行运算的模型,两法所得 F 值可以相互换算。初步设计了符合操作定义的田间试验方法,用相应试验所得数据可算出 F 值。根据作者用第一手实测数据估算两种 F 值的经验,认为两种 F 值在测定和应用上互有优劣,可因地制宜采用,但均需作好数据资料测定的试验设计,使之符合操作定义的要求,并精心执行、力求缩小试验误差,以使所得 F 值能有实用价值。
基金Funds of China West Normal University (17YC332 17YC114)+2 种基金the National Natural Science Foundation of China (31572293)the Natural Science project of the Sichuan Department of Education (16ZB0177)the Fundamental Research Funds of China West Normal University (14D010)
文摘The 5.12 Earthquake in 2008 and 8.14 Debris Flow in 2010 resulted in large-scale landslides that disturbed vast areas of vegetation in the Hongchun Gully, Wenchuan County, China. To define the specific characteristics of vegetation restoration during natural recovery after catastrophic events,vegetation species composition and interspecific associations were investigated on this typical landslide. Field survey data selected from a total of 51 sample plots belonged to seven belt transects and were analysed by Schluter's variance ratio, pearson's chi-squared test, Spearman's correlation coefficients and ecological species groups. Plant communities on the landslide consisted of 78 species, 65 genera and52 families. Of the total of 78 species, 25 are identified as dominant species, among which Camptotheca acuminate, Toxicodendron vernicifluum, Coriaria nepalensis, Robinia pseudoacacia, Buddleja alternifolia, Anemone vitifolia and Nephrolepis auriculata play a constructive role during the natural afforestation. Moreover, according to environmental and ecological factors, these 25 dominant species could be divided into four ecological species groups.This study found that even though the landslide had frequently suffered from interference due to heavy rain, the vegetation succession processes are ongoing,and it is now at a shrub–herb community succession stage, which indicates that vegetation can naturally recover in the denuded sites. This study provides a useful insight into the ecological interactions and interdependence between plant species during the natural recovery of vegetation and provides valuable information on vegetation recovery modelling in the landslide area.
