A mixture of six Georgia isolates of Phytophthora capsici (Leon.), the causal agent of phytophthora blight, were used for greenhouse mass screening of over 700 accessions of Capsicum annuum for both stem blight and fo...A mixture of six Georgia isolates of Phytophthora capsici (Leon.), the causal agent of phytophthora blight, were used for greenhouse mass screening of over 700 accessions of Capsicum annuum for both stem blight and foliar blight. From this screening, it was determined that resistance to both forms of the disease were relatively common in the germplasm, but resistance to one form of the disease was not strongly correlated to resistance to the other form. Ten accessions previously shown to possess root rot resistance were tested for resistance to stem rot and leaf blight, and were found to also be highly resistant to these forms of the disease. It appears that single accessions have resistance to foliar, stem and root rot caused by P. capsici, which may simplify breeding for resistance to all three forms of the disease.展开更多
为检测和鉴定引起西藏日喀则地区的辣椒根腐病病原菌种类,2024年7—9月从西藏日喀则白朗县巴扎乡彭仓村、桑珠孜区聂日雄乡盘孔村、江孜县达孜乡德吉村和拉孜县拉孜镇玉哲村4个区域采集了16份辣椒感病植株样品。采用常规组织分离法对发...为检测和鉴定引起西藏日喀则地区的辣椒根腐病病原菌种类,2024年7—9月从西藏日喀则白朗县巴扎乡彭仓村、桑珠孜区聂日雄乡盘孔村、江孜县达孜乡德吉村和拉孜县拉孜镇玉哲村4个区域采集了16份辣椒感病植株样品。采用常规组织分离法对发病部位进行病原菌分离与培养后得到25株病原真菌,利用显微形态学观察将分离物代表菌株分为LJ1、LJ2和LJ3共3类真菌分离物。结合分子生物学方法及系统发育树构建,将LJ1类病原菌鉴定为镰孢菌属茄病镰孢菌,LJ2类病原菌为丝核菌属立枯丝核菌AG-4菌丝融合群的HGⅠ亚群(Rhizoctonia solani AG 4 HG-Ⅰ),LJ3类病原菌为镰孢菌属尖孢镰孢菌。采用幼苗刺伤接种法进行病原菌致病性评价,3类真菌分离物均能够侵染辣椒幼苗造成根腐病,且尖孢镰孢菌致病性最强。日喀则各地辣椒根腐病病原菌优势菌有差异,尖孢镰孢菌是优势致病菌,分离频率为52.0%;茄病镰孢菌分离频率为32.0%;立枯丝核菌分离频率为16.0%。西藏日喀则地区的辣椒根腐病是由尖孢镰孢菌、茄病镰孢菌和立枯丝核菌AG-4菌丝融合群的HGI亚群复合侵染导致,茄病镰孢菌和立枯丝核菌AG-4菌丝融合群的HGI亚群均是首次在西藏被分离鉴定。展开更多
Greenhouse studies were performed to determine the reactions of 10 “California Wonder” (Capsicum annuum) accessions to the three forms of Phytophthora blight (root rot, stem blight and foliar blight) caused by Phyto...Greenhouse studies were performed to determine the reactions of 10 “California Wonder” (Capsicum annuum) accessions to the three forms of Phytophthora blight (root rot, stem blight and foliar blight) caused by Phytophthora capsici. Differences in root rot, stem blight and foliar blight severities among accessions were significant. The accessions consistently differentiated into two groups across the three disease syndromes. Simple sequence repeat (SSR) markers showed variability both within and between accessions of California Wonder. The variability in the responses to the three forms of Phytophthora blight does not warrant its usefulness as a standard susceptible control in studies involving the Capsicum-P. capsici patho-system.展开更多
文摘A mixture of six Georgia isolates of Phytophthora capsici (Leon.), the causal agent of phytophthora blight, were used for greenhouse mass screening of over 700 accessions of Capsicum annuum for both stem blight and foliar blight. From this screening, it was determined that resistance to both forms of the disease were relatively common in the germplasm, but resistance to one form of the disease was not strongly correlated to resistance to the other form. Ten accessions previously shown to possess root rot resistance were tested for resistance to stem rot and leaf blight, and were found to also be highly resistant to these forms of the disease. It appears that single accessions have resistance to foliar, stem and root rot caused by P. capsici, which may simplify breeding for resistance to all three forms of the disease.
文摘为检测和鉴定引起西藏日喀则地区的辣椒根腐病病原菌种类,2024年7—9月从西藏日喀则白朗县巴扎乡彭仓村、桑珠孜区聂日雄乡盘孔村、江孜县达孜乡德吉村和拉孜县拉孜镇玉哲村4个区域采集了16份辣椒感病植株样品。采用常规组织分离法对发病部位进行病原菌分离与培养后得到25株病原真菌,利用显微形态学观察将分离物代表菌株分为LJ1、LJ2和LJ3共3类真菌分离物。结合分子生物学方法及系统发育树构建,将LJ1类病原菌鉴定为镰孢菌属茄病镰孢菌,LJ2类病原菌为丝核菌属立枯丝核菌AG-4菌丝融合群的HGⅠ亚群(Rhizoctonia solani AG 4 HG-Ⅰ),LJ3类病原菌为镰孢菌属尖孢镰孢菌。采用幼苗刺伤接种法进行病原菌致病性评价,3类真菌分离物均能够侵染辣椒幼苗造成根腐病,且尖孢镰孢菌致病性最强。日喀则各地辣椒根腐病病原菌优势菌有差异,尖孢镰孢菌是优势致病菌,分离频率为52.0%;茄病镰孢菌分离频率为32.0%;立枯丝核菌分离频率为16.0%。西藏日喀则地区的辣椒根腐病是由尖孢镰孢菌、茄病镰孢菌和立枯丝核菌AG-4菌丝融合群的HGI亚群复合侵染导致,茄病镰孢菌和立枯丝核菌AG-4菌丝融合群的HGI亚群均是首次在西藏被分离鉴定。
文摘Greenhouse studies were performed to determine the reactions of 10 “California Wonder” (Capsicum annuum) accessions to the three forms of Phytophthora blight (root rot, stem blight and foliar blight) caused by Phytophthora capsici. Differences in root rot, stem blight and foliar blight severities among accessions were significant. The accessions consistently differentiated into two groups across the three disease syndromes. Simple sequence repeat (SSR) markers showed variability both within and between accessions of California Wonder. The variability in the responses to the three forms of Phytophthora blight does not warrant its usefulness as a standard susceptible control in studies involving the Capsicum-P. capsici patho-system.
