Studies on epidemics of the citrus Huanglongbing and yield loss in early maturing citrus orchards | 早熟柑橘黄龙病流行与产量损失关系研究

صينى. 摘　　要：2002-2009年测定了早熟柑橘品种‘宫川’（以下简称早熟柑橘）黄龙病病情扩散速率与产量的关系。结果表明：早熟柑橘黄龙病病情随时序推进呈Logistic曲线上升，总体上病情扩散速率为先快后慢，并呈现从强到弱的趋势特征，前4年因病原基数低而病情增长幅度大，扩散速率快；后4年因病原基数处于较高状态，而相对传染扩散速率减慢，表现扩散速率较平缓，形成随病级上升单株结果数减少、健果率下降、产量下降的危害规律；由此建立早熟‘宫川’黄龙病病情扩散速率（P）与发病时序（N）的关系模型为：P=65.082 7/［1＋EXP（4.017 8-0.752 838N）］（R=0.999 1. ____攴⒉÷剩P）与病情指数（M）关系模型为：M=0.571 2P-2.398 6（R=0.993 7. ____煌_〖叮m）病树与其果数（G）、健果率（J）的关系模型：G=1 344.833 9/［1＋EXP（-3.693 7＋0.549 3m）］（R=-0.988 6. ___J=91.560 5/［1＋EXP（-6.677 0＋1.090 4m）］（R=-0.974 2. ___徊煌_〖叮m）病树与其单果重（W）、单株产量（Y）、产量损失率（Rp）的关系模型：W=95.427 8/［1＋EXP（-29.770 1＋3.993 2m）］ （R=-0.990 6. ___Y=44.138 2_/［1＋EXP（-4.019 2＋0.689 1m）］（R=-0.984 2. _____p=131.536 4/［1＋EXP（4.239 9-0.592 4m）］（R=-0.984 7.

إنجليزي. The epidemic diffusion velocity of Huanglongbing （HLB） and the yield loss due to it were measured in early_maturing citrus orchards from 2002 to 2009. The results showed that HLB rised by Logistic curve with temporal evolution. General tendency of the epidemic diffusion velocity was quick and strong first, followed by slow and weak. A linear model between the epidemic diffusion velocity of HLB （P） and morbidity time series （N） was established： P=65.082 7/[1＋EXP（4.017 8-0.752 838N）]; the relationship between morbidity （P） and disease index （M） was： M=0.571 2P-2.398 6; the relationships among different disease stage of trees （m）, fruit number （G） and healthy fruit rate （J） was： G=1 344.833 9/[1＋EXP（-3.693 7＋0.549 3m）] and J=91.560 5/[1＋_EXP（-6.677 0＋1.090 4m）]; the relationships among_ different disease stage （m） of diseased trees, fruit weight （W） and grain yield per plant （Y） was： W=95.427 8_/[1＋EXP（-29.770 1＋3.993 2m）];Y=44.138 2/[1＋EXP（-4.019 2_＋0.689 1m）]; the relationship between different disease stage （m） of diseased trees and yield loss rate （R_p） was： R_p=131.536 4/[1＋EXP（4.239 9_-0.592 4m）]. Studies on epidemics of the citrus Huanglongbing and yield loss in early maturing citrus orchards Yu Jihua1,Wang Enguo2,Zhang Minrong1,Liang Kehong3,Ye Zhiyong1,Tao Jian1 1. Plant Quarantine Station of Huangyan District, Taizhou318020, China;_2. Plant Protection and Quarantine Station of Linhai City, Linhai317000, China;_3. Fruit Technology Promotion Station of Huangyan District, Taizhou318020, China Received Revised Online Accepted Abstract The epidemic diffusion velocity of Huanglongbing （HLB） and the yield loss due to it were measured in early_maturing citrus orchards from 2002 to 2009. The results showed that HLB rised by Logistic curve with temporal evolution. General tendency of the epidemic diffusion velocity was quick and strong first, followed by slow and weak. A linear model between the epidemic diffusion velocity of HLB （P） and morbidity time series （N） was established： P=65.082 7/[1＋EXP（4.017 8-0.752 838N）]; the relationship between morbidity （P） and disease index （M） was： M=0.571 2P-2.398 6; the relationships among different disease stage of trees （m）, fruit number （G） and healthy fruit rate （J） was： G=1 344.833 9/[1＋EXP（-3.693 7＋0.549 3m）] and J=91.560 5/[1＋_EXP（-6.677 0＋1.090 4m）]; the relationships among_ different disease stage （m） of diseased trees, fruit weight （W） and grain yield per plant （Y） was： W=95.427 8_/[1＋EXP（-29.770 1＋3.993 2m）];Y=44.138 2/[1＋EXP（-4.019 2_＋0.689 1m）]; the relationship between different disease stage （m） of diseased trees and yield loss rate （R_p） was： R_p=131.536 4/[1＋EXP（4.239 9_-0.592 4m）].