Rice blast disease, caused by a seed-borne fungus Pyricularia grisea, is an important and serious disease of rice (Oryza sativa L.) worldwide. The disease has been reported to cause yield losses of up to 40% in Tanzan...Rice blast disease, caused by a seed-borne fungus Pyricularia grisea, is an important and serious disease of rice (Oryza sativa L.) worldwide. The disease has been reported to cause yield losses of up to 40% in Tanzania. Studies were conducted to determine the effect of aqueous extracts of Aloe vera, Allium sativum, Annona muricata, Azadirachta indica, Bidens pilosa, Camellia sinensis, Chrysanthemum coccineum, processed Coffee arabica, Datura stramonium, Nicotiana tabacum and Zingiber officinalis for control of rice blast disease (Pyricularia grisea) in-vitro and in-vivo. The results indicate that processed C. arabica at 10% and 25% (v/v) had the highest (81.12%) and (89.40%) inhibitory effect, respectively, against P. grisea. Aqueous extract from N. tabacum at 10% concentration ranked third (80.35%) in inhibiting P. grisea. These were followed by extracts from 25% A. vera (79.45%) and 25% C. coccineum flower (78.83%). The results also indicate that, extracts from A. indica, A. vera, A. sativum, C. arabica, D. stramonium, C. sinensis, Z. officinalis and N. tabacum did not have any phytotoxic effect on seed germination, shoot height, root length, dry weight, seedling growth and seedling vigour index. These plant extracts can thus be used for rice seed treatment to manage rice blast disease.展开更多
Blast has been a continuous threat to finger millet production in semi-arid tropics.The disease is economically important and widespread in finger millet major growing areas of western,Nyanza and Rift valley in Kenya....Blast has been a continuous threat to finger millet production in semi-arid tropics.The disease is economically important and widespread in finger millet major growing areas of western,Nyanza and Rift valley in Kenya.Host resistance is the most economical and effective means of controlling the disease as finger millet is grown by resource-poor farmers.This study evaluated a hundred finger millet genotypes for resistance to blast at KALRO(Kenya Agricultural Research and Livestock Organization)Kakamega and Alupe,Kenya for two seasons in 2011/2012 in a lattice square design for two seasons each.Data on blast incidence and severity were measured.Data were analyzed using ANOVA(analysis of variance)and means separated using Duncan multiple range test(DMRT)at p<0.005.The results showed that disease severity was highest in early maturing varieties and lowest in the late maturing varieties.The most resistant genotypes were:GBK000702,GBK000513,GBK029869,GULU-E,GBK000752 and Busibwabo.Pearson correlation analysis between neck severity and physiological maturity was positively significant(r=-0.47).A strong positive correlation between finger severity and neck severity(r=0.87)was observed.These tolerant genotypes could be utilized as donor parents for breeding durable blast resistant varieties.展开更多
冈 4 6B(G4 6B)是水稻生产应用中的一个农艺性状十分优良的保持系 ,其主要的缺陷是稻瘟病抗性较弱 ,通过对地谷 ,BL 1,Pi 4号等三个分别含抗病基因Pi d(t) 1 、Pi b、Pi ta2 的稻瘟病抗性材料与G4 6B聚合杂交 ,并利用抗病基因连锁的分...冈 4 6B(G4 6B)是水稻生产应用中的一个农艺性状十分优良的保持系 ,其主要的缺陷是稻瘟病抗性较弱 ,通过对地谷 ,BL 1,Pi 4号等三个分别含抗病基因Pi d(t) 1 、Pi b、Pi ta2 的稻瘟病抗性材料与G4 6B聚合杂交 ,并利用抗病基因连锁的分子标记对杂交后代进行辅助选择 ,在聚合杂交的F2代及B1C1代群体中共获得了 15株含Pi d(t) 1 、Pi b、Pi ta2 等三个抗稻瘟病基因的材料 ,其可能的基因型分别为 :三基因杂合体Pi d(t) 1 pi d(t) 1 Pi bpi b Pi ta2 pi ta2 4株 ,双基因杂合体 10株 ,其中Pi d(t) 1 Pi d(t) 1 Pi bpi b Pi ta2 pi ta2 6株 ,Pi d(t) 1 pi d(t) 1 Pi bpi b Pi ta2 Pi ta2 3株 ,Pi d(t) 1 pi d(t) 1 Pi bPi b Pi ta2 pi ta2 1株 ,双基因纯合体Pi d(t) 1 Pi d(t) 1 Pi bpi b Pi ta2 Pi ta2仅 1株 ,这一研究结果为进一步改良G4 6B的稻瘟病抗性奠定了基础 ,同时这一研究结果表明利用分子标记可快速、有效地实现多个抗病基因的聚合 。展开更多
文摘Rice blast disease, caused by a seed-borne fungus Pyricularia grisea, is an important and serious disease of rice (Oryza sativa L.) worldwide. The disease has been reported to cause yield losses of up to 40% in Tanzania. Studies were conducted to determine the effect of aqueous extracts of Aloe vera, Allium sativum, Annona muricata, Azadirachta indica, Bidens pilosa, Camellia sinensis, Chrysanthemum coccineum, processed Coffee arabica, Datura stramonium, Nicotiana tabacum and Zingiber officinalis for control of rice blast disease (Pyricularia grisea) in-vitro and in-vivo. The results indicate that processed C. arabica at 10% and 25% (v/v) had the highest (81.12%) and (89.40%) inhibitory effect, respectively, against P. grisea. Aqueous extract from N. tabacum at 10% concentration ranked third (80.35%) in inhibiting P. grisea. These were followed by extracts from 25% A. vera (79.45%) and 25% C. coccineum flower (78.83%). The results also indicate that, extracts from A. indica, A. vera, A. sativum, C. arabica, D. stramonium, C. sinensis, Z. officinalis and N. tabacum did not have any phytotoxic effect on seed germination, shoot height, root length, dry weight, seedling growth and seedling vigour index. These plant extracts can thus be used for rice seed treatment to manage rice blast disease.
文摘Blast has been a continuous threat to finger millet production in semi-arid tropics.The disease is economically important and widespread in finger millet major growing areas of western,Nyanza and Rift valley in Kenya.Host resistance is the most economical and effective means of controlling the disease as finger millet is grown by resource-poor farmers.This study evaluated a hundred finger millet genotypes for resistance to blast at KALRO(Kenya Agricultural Research and Livestock Organization)Kakamega and Alupe,Kenya for two seasons in 2011/2012 in a lattice square design for two seasons each.Data on blast incidence and severity were measured.Data were analyzed using ANOVA(analysis of variance)and means separated using Duncan multiple range test(DMRT)at p<0.005.The results showed that disease severity was highest in early maturing varieties and lowest in the late maturing varieties.The most resistant genotypes were:GBK000702,GBK000513,GBK029869,GULU-E,GBK000752 and Busibwabo.Pearson correlation analysis between neck severity and physiological maturity was positively significant(r=-0.47).A strong positive correlation between finger severity and neck severity(r=0.87)was observed.These tolerant genotypes could be utilized as donor parents for breeding durable blast resistant varieties.
基金国家 8 63高技术发展与研究计划项目 (No .2 0 0 4AA2 1113 2 )教育部优秀博士论文基金 (No .2 0 0 0 5 4)~~
文摘冈 4 6B(G4 6B)是水稻生产应用中的一个农艺性状十分优良的保持系 ,其主要的缺陷是稻瘟病抗性较弱 ,通过对地谷 ,BL 1,Pi 4号等三个分别含抗病基因Pi d(t) 1 、Pi b、Pi ta2 的稻瘟病抗性材料与G4 6B聚合杂交 ,并利用抗病基因连锁的分子标记对杂交后代进行辅助选择 ,在聚合杂交的F2代及B1C1代群体中共获得了 15株含Pi d(t) 1 、Pi b、Pi ta2 等三个抗稻瘟病基因的材料 ,其可能的基因型分别为 :三基因杂合体Pi d(t) 1 pi d(t) 1 Pi bpi b Pi ta2 pi ta2 4株 ,双基因杂合体 10株 ,其中Pi d(t) 1 Pi d(t) 1 Pi bpi b Pi ta2 pi ta2 6株 ,Pi d(t) 1 pi d(t) 1 Pi bpi b Pi ta2 Pi ta2 3株 ,Pi d(t) 1 pi d(t) 1 Pi bPi b Pi ta2 pi ta2 1株 ,双基因纯合体Pi d(t) 1 Pi d(t) 1 Pi bpi b Pi ta2 Pi ta2仅 1株 ,这一研究结果为进一步改良G4 6B的稻瘟病抗性奠定了基础 ,同时这一研究结果表明利用分子标记可快速、有效地实现多个抗病基因的聚合 。
