1.Introduction Cereal crop plants,which provide human societies around the world with a large proportion of their daily carbohydrate requirements,are subject to continual attack by potentially pathogenic fungi.The fun...1.Introduction Cereal crop plants,which provide human societies around the world with a large proportion of their daily carbohydrate requirements,are subject to continual attack by potentially pathogenic fungi.The fungi can penetrate the outer layers of plants in a number of ways,but plants will usually resist infection.However,in some cases,the fungi will overcome the plant’s defenses and establish infection.When agriculturally important plant species succumb to pathogen attack,the resulting reduction in yields or complete destruction of the crop can have devastating social,environmental,and financial effects on national and international communities.During the co-evolution of plants and pathogenic fungi,plants have developed a range of defense strategies against fungal infection,while the fungi,in parallel,have developed new tactics to achieve penetration and infection,and/or to overcome the existing resistance mechanisms of plants.This constant battle for supremacy continues today,and a key and continual objective in cropimprovement programs around the world is to provide plants with an(at least temporary)advantage over the fungi.展开更多
In cereals, the presence of soluble polysaccharides including(1,3;1,4)-b-glucan has downstream implications for human health, animal feed and biofuel applications. Sorghum bicolor(L.) Moench is a versatile crop, b...In cereals, the presence of soluble polysaccharides including(1,3;1,4)-b-glucan has downstream implications for human health, animal feed and biofuel applications. Sorghum bicolor(L.) Moench is a versatile crop, but there are limited reports regarding the content of such soluble polysaccharides.Here, the amount of(1,3;1,4)-b-glucan present in sorghum tissues was measured using a Megazyme assay. Very low amounts were present in the grain, ranging from 0.16%–0.27%(w/w), while there was a greater quantity in vegetative tissues at 0.12–1.71%(w/w). The fine structure of(1,3;1,4)-b-glucan, as denoted by the ratio of cellotriosyl and cellotetraosyl residues,was assessed by high performance liquid chromatography(HPLC) and ranged from 2.6–3:1 in the grain, while ratios in vegetative tissues were lower at 2.1–2.6:1. The distribution of(1,3;1,4)-b-glucan was examined using a specific antibody and observed with fl uorescence and transmission electron microscopy. Micrographs showed a variable distribution of(1,3;1,4)-b-glucan in fl uenced by temporal and spatial factors. The sorghum orthologs of genes implicated in the synthesis of(1,3;1,4)-b-glucan in other cereals, such as the Cellulose synthase-like(Csl) F and H gene families were de fined.Transcript pro filing of these genes across sorghum tissues was carried out using real-time quantitative polymerase chain reaction, indicating that, as in other cereals, Csl F6 transcripts dominated.展开更多
文摘1.Introduction Cereal crop plants,which provide human societies around the world with a large proportion of their daily carbohydrate requirements,are subject to continual attack by potentially pathogenic fungi.The fungi can penetrate the outer layers of plants in a number of ways,but plants will usually resist infection.However,in some cases,the fungi will overcome the plant’s defenses and establish infection.When agriculturally important plant species succumb to pathogen attack,the resulting reduction in yields or complete destruction of the crop can have devastating social,environmental,and financial effects on national and international communities.During the co-evolution of plants and pathogenic fungi,plants have developed a range of defense strategies against fungal infection,while the fungi,in parallel,have developed new tactics to achieve penetration and infection,and/or to overcome the existing resistance mechanisms of plants.This constant battle for supremacy continues today,and a key and continual objective in cropimprovement programs around the world is to provide plants with an(at least temporary)advantage over the fungi.
基金supported by funding from the Australian Development Scholarship (ADS),Australia Awards and the Australian Research Council Centre of Excellence in Plant Cell Walls,The University of Adelaide
文摘In cereals, the presence of soluble polysaccharides including(1,3;1,4)-b-glucan has downstream implications for human health, animal feed and biofuel applications. Sorghum bicolor(L.) Moench is a versatile crop, but there are limited reports regarding the content of such soluble polysaccharides.Here, the amount of(1,3;1,4)-b-glucan present in sorghum tissues was measured using a Megazyme assay. Very low amounts were present in the grain, ranging from 0.16%–0.27%(w/w), while there was a greater quantity in vegetative tissues at 0.12–1.71%(w/w). The fine structure of(1,3;1,4)-b-glucan, as denoted by the ratio of cellotriosyl and cellotetraosyl residues,was assessed by high performance liquid chromatography(HPLC) and ranged from 2.6–3:1 in the grain, while ratios in vegetative tissues were lower at 2.1–2.6:1. The distribution of(1,3;1,4)-b-glucan was examined using a specific antibody and observed with fl uorescence and transmission electron microscopy. Micrographs showed a variable distribution of(1,3;1,4)-b-glucan in fl uenced by temporal and spatial factors. The sorghum orthologs of genes implicated in the synthesis of(1,3;1,4)-b-glucan in other cereals, such as the Cellulose synthase-like(Csl) F and H gene families were de fined.Transcript pro filing of these genes across sorghum tissues was carried out using real-time quantitative polymerase chain reaction, indicating that, as in other cereals, Csl F6 transcripts dominated.