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111.
Marcel Maymon Gunjan Sharma Marina Hazanovsky Orly Erlich Shir Pessach Stanley Freeman Leah Tsror 《Plant pathology》2021,70(4):793-803
Fusarium wilt, caused by Fusarium oxysporum, is a major disease of jojoba, causing serious economic losses. This study was aimed at characterizing the Fusarium populations associated with jojoba in Israel. Fifty Fusarium isolates used in this study included 23 isolates from the 1990s (“past”) and 27 recently isolated (“recent”). All the isolates were characterized by arbitrarily primed (ap)-PCR and 16 representatives were additionally delineated using multilocus (tef1, rpb1, rpb2) phylogeny and evaluated for their pathogenic potential. Consequently, 88% of the isolates were identified and characterized to the F. oxysporum species complex. The remaining 12% grouped within the F. fujikuroi, F. solani, and F. redolens species complexes. Variations in the infection rate (16.7%–100%), disease symptoms (0.08–1.25, on a scale of 0–3), and fungal colonization index (0.67–2.17, on a scale of 0–4) were observed within the tested isolates, with no significant differences between the past and recent isolates. The representative isolates were assigned to 11 groups based on ap-PCR. Pathogenicity tests showed that isolates from Groups II, IV, and V were the most aggressive, whereas isolates from Groups III, VIII, and IX were the least aggressive. Among the tested isolates, F. oxysporum sensu lato was the most aggressive, followed by F. proliferatum, while F. nygamai was the least aggressive. This study demonstrates the complexity and genetic diversity of Fusarium wilt on jojoba in Israel, indicating possible multiple introductions of infected germplasm into the country. 相似文献
112.
水稻中413的广亲恢性及其系列组合 总被引:8,自引:2,他引:8
中413是从50465中经系统选育而成的广亲和恢复系。与籼型测验种IR36,南京11测交,F1结实率分别为75.5%和80.0%;与粳型测验种秋光,Balilla测交,结实率分别为71.4%和53.2%。对野败,矮败,Dissi,马尾粘等胞质不育系均具有较强的恢复能力。以中413为广亲恢系而配制的系列组合均有较强的杂种优势,在不同地区,不同季节种植均比对照汕优63和汕优10号增产或极显著增产。作单季种植,亩产可达700 kg以上;作双晚栽培,亩产可达600 kg左右。表现为秧苗素质号,生长势旺,耐肥抗倒,穗大,叶面积系数大,物质生产力高,穗多,库源关系协调。中413系列组合不仅表现较强的杂种优势,而且较好地克服了籼粳亚种间优势利用种F1结实率偏低,籽粒不饱满,植株偏高和生育期偏长等障碍。 相似文献
113.
有关三系籼粳杂交稻的广亲和测验种的探讨 总被引:2,自引:1,他引:2
有关三系籼粳杂交稻的广亲和测验种的探讨高勇,滕利生,申宗坦(浙江农业大学农学系,杭州310029)关键词:籼粳杂交稻;测验种;广亲和性DiscussionofTesterofWideCompatibilityinThree-lineindica-ja... 相似文献
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116.
Qiang Zeng Lihua Deng Wenbin Hu Xingjian He Qiucheng Meng Jianghui Yu Jinjiang Li Lushui Weng Guoying Xiao 《水稻科学》2020,27(3):215-226
Weeds and insect pests are two important biotic stresses resulting in yield loss in rice, and wide compatibility is the essential characteristic of breeding inter-subspecific hybrid rice. This study focused on glyphosate resistance, lepidopteran resistance and wide compatibility as well as identification of molecular and some agronomic characteristics of transgenic male sterile line E1 C4008 S. The results indicated that glyphosate resistance gene Epsps# and lepidopteran resistance gene Cry1 ca~# were transferred into japonica wide compatibility male sterile line 4008 S by Agrobacterium-mediated method, and four independent transformation events named E1 C4008 S-1, E1 C4008 S-2, E1 C4008 S-3 and E1 C4008 S-4 were obtained, in which E1 C4008 S-3 and E1 C4008 S-4 were of single copy insertion. The EPSPS protein contents of E1 C4008 S-3 and E1 C4008 S-4 in different organs were significantly different both in descending order of leaf stem root, and ranged from 300.58 to 1410.69 μg/g at the tillering stage. The glyphosate tolerable concentration(dosage) of E1 C4008 S-3 and E1 C4008 S-4 reached at least 16 g/L(54.42 kg/hm2), and the seeds of E1 C4008 S-4 can germinate normally on the medium containing 1 g/L glyphosate. The CRY1 C protein contents of E1 C4008 S-3 and E1 C4008 S-4 in different organs were significantly different both in descending order of leaf stem root, and ranged from 0.62 to 2.43 μg/g at the tillering stage. The larvae mortalities of rice leaf rollers fed on leaves of E1 C4008 S-3 and E1 C4008 S-4 for 5 d were 95.35% and 97.77%, respectively, while the average mortalities of silkworms fed with protein extracts from leaves of E1 C4008 S-3 and E1 C4008 S-4 reached 94.55% and 83.64%, respectively. The results suggested that wide compatibility and evaluated agronomic traits of E1 C4008 S-4 were not significantly changed by insertion of the exogenous genes. Overall, a novel male sterile germplasm with glyphosate resistance, lepidopteran resistance and wide compatibility was verified to be developed in rice. 相似文献
117.
苏云金芽胞杆菌(Bacillus thuringiensis,Bt)可产生多种杀虫活性物质,是一种应用最广泛的微生物杀虫剂。最近研究表明Bt对化学杀虫剂抗性害虫有较好的防治效果,并且与化学杀虫剂的联合使用可以提高杀虫效果,减少化学杀虫剂的用量。为了进一步设计更好的Bt与化学杀虫剂协同控害方案,本论文研究了不同亚种的Bt菌株与常用化学杀虫剂的兼容性。泛基因组分析表明不同亚种的Bt菌株在基因组成上有较大差异,说明Bt菌株对化学杀虫剂的反应可能会有所不同。进一步化学杀虫剂对Bt增殖影响分析结果显示,溴虫腈对大部分Bt测试菌株有抑制,说明Bt与化学杀虫剂协同使用时需要测定两者兼容性。高效氯氰菊酯对所有常用的防治鳞翅目害虫的Bt杀虫剂亚种类型库斯塔克亚种(Bt kurstaki,Btk)和鲇泽亚种(Bt aizawai,Bta)菌株影响都不大,可以进行协同使用;氯虫苯甲酰胺和茚虫威对Btk菌株HD1有一定抑制作用,定虫隆对其有较好的促进作用,说明HD1与定虫隆协同使用效果更好;茚虫威对Bta菌株G03影响较小,定虫隆对其有一定的抑制作用,氯虫苯甲酰胺对G03则有一定的促进作用,说明G03及其衍生菌株可以与氯虫苯甲酰胺、茚虫威协同使用。本研究结果说明Bt菌株对不同杀虫剂的敏感性是有差异的,可以通过筛选获得兼容性好的组合,为进一步制定Bt杀虫剂与化学杀虫剂配伍方案与协同使用技术提供了理论指导与数据参考,对实现化学农药减量施用具有重要的指导意义。 相似文献
118.
[目的]利用分子标记辅助选择培育水稻广亲和保持系,为水稻籼粳亚种杂种优势利用提供参考.[方法]用4个不育系博A、天A、青A、62A与24个水稻姊妹系杂交,测定其恢保性;同时利用与Sn5紧密连锁的SSR标记GXR6对24个姊妹系进行检测;再通过籼粳测交验证其亲和性.[结果]24个姊妹系中除B11、B13、B14、B15外,其余B1~B10、B12、B 16~B24等20个姊妹系花粉不育度均达100.0%,对4个不育系博A、青A、天A、62A均保持不育.SSR分子标记检测结果显示,B1、B2、B4~B7、B10~B12、B14~B16、B 18~B20、B22、B23等17个姊妹系均携带187R的广亲和基因Sn5;但与日本晴和巴利拉测交验证结果显示,仅B1、B4具有亲和性,B9虽未携带Sn5却具有亲和性,其测交组合F1代植株结实率极显著高于桂B测交的结实率(P<0.01)而低于测验种自身的结实率(桂B结实率79.79%,日本晴76.87%,巴利拉73.65%),B1、B4和B9属于中亲和力品系.[结论]筛选获得的广亲和保持系B1、B4和B9,可用来改造现有不育系,充分发挥籼粳亚种杂种优势,提高杂交水稻产量,具有较好的应用前景. 相似文献
119.
BACKGROUND: The possibility of gene flow from transgenic crops to wild relatives may be affected by reproductive capacity between them. The potential gene flow from two transgenic rice lines containing the bar gene to five accessions of weedy rice (WR1–WR5) was determined through examination of reproductive compatibility under controlled pollination. RESULTS: The pollen grain germination of two transgenic rice lines on the stigma of all weedy rice, rice pollen tube growth down the style and entry into the weedy rice ovary were similar to self‐pollination in weedy rice. However, delayed double fertilisation and embryo abortion in crosses between WR2 and Y0003 were observed. Seed sets between transgenic rice lines and weedy rice varied from 8 to 76%. Although repeated pollination increased seed set significantly, the rank of the seed set between the weedy rice accessions and rice lines was not changed. The germination rates of F1 hybrids were similar or greater compared with respective females. All F1 plants expressed glufosinate resistance in the presence of glufosinate selection pressure. CONCLUSIONS: The frequency of gene flow between different weedy rice accessions and transgenic herbicide‐resistant rice may differ owing to different reproductive compatibility. This result suggests that, when wild relatives are selected as experimental materials for assessing the gene flow of transgenic rice, it is necessary to address the compatibility between transgenic rice and wild relatives. Copyright © 2009 Society of Chemical Industry 相似文献
120.