Expression of a rice chitinase gene in transgenic banana ('Gros Michel', AAA genome group) confers resistance to black leaf streak disease

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Resistance to Anticarsia gemmatalis Hübner (Lepidoptera, Noctuidae) in transgenic soybean (Glycine max (L.) Merrill Fabales, Fabaceae) cultivar IAS5 expressing a modified Cry1Ac endotoxin

Somatic embryos of the commercial soybean (Glycine max) cultivar IAS5 were co-transformed using particle bombardment with a synthetic form of the Bacillus thuringiensis delta-endotoxin crystal protein gene cry1Ac, the beta-glucuronidase reporter gene gusA and the hygromycin resistance gene hpt. Hygromycin-resistant tissues were proliferated individually to give rise to nine sets of clones corresponding to independent transformation events. The co-bombardment resulted in a co-transformation efficiency of 44%. Many histodifferentiated embryos and 30 well-developed plants were obtained. Twenty of these plants flowered and fourteen set seeds. The integration and expression of the cry1Ac, gusA and hpt transgenes into the genomes of a sample of transformed embryos and all T0, T1, T2 and T3 plants were confirmed by Gus activity, PCR, Southern and western blot, and ELISA techniques. Two T0 plants out of the seven co-transformed plants produced seeds and were analyzed for patterns of integration and inheritance until the T3 generation. Bioassays indicated that the transgenic plants were highly toxic to the velvetbean caterpillar Anticarsia gemmatalis, thus offering a potential for effective insect resistance in soybean

Genetics and molecular breeding in Lolium/Festuca grass species complex

Perennial ryegrass ( Lolium perenne ) and Italian ryegrass ( L. multiflorum ) are regarded as ideal grass species for use as animal forage in temperate grassland agriculture. Ryegrasses establish and grow quickly and provide dense swards of highly nutritious and easily digestible forage that can be turned into healthy meat and animal products for human consumption. However, their use is restricted as they lack persistency, especially in marginal areas and locations that are subject to summer and winter stresses and drought stress. Close relative species from within genus Festuca are much better adapted to such abiotic stresses but, by contrast, do not compare well in animal forage provision to Lolium species as they show poor establishment and comparatively lower quality characteristics. Lolium and Festuca species hybridize naturally and exhibit high frequencies of gene exchange in the hybrid condition. Intergeneric hybrids ( Festulolium ) between Lolium and Festuca species are being used to broaden the gene pool and to provide the plant breeder with options to combine high quality traits with broad adaptations to a range of environmental constraints. Festulolium varieties have promise as novel grasses with high forage quality and resistance to environmental stress and can thereby improve grassland productivity, persistency and benefit incomes. Recent progress on Festulolium breeding programs is described here. Conventional forage grass breeding programs rely on basis observable phenotypes using the natural genetic variation found between and within varieties or ecotypes. Genetic improvement of forage grasses by conventional breeding programs is very slow due to the obligate outbreeding and perennial nature of grasses. Advances in genomics and gene manipulation can complement and enhance conventional plant breeding programs. Many studies concerning the implementation of DNA markers, high-throughout gene discovery, genome-wide gene expression analysis and gene manipulation are currently being conducted for forage grasses. Recent progress on molecular and genomic research activity in the genus Lolium and Festuca is reviewed