Sinorhizobium fredii USDA257 forms nitrogen-fixing nodules on primitive soybean (Glycine max) cultivar Peking but fails to nodulate the improved cultivar McCall. Cultivar specificity is governed by a plasmid-borne locus, nolXBTUV. By DNA sequence analysis, we have identified two open reading frames, y4yA and y4yB, immediately downstream of nolX. Northern (RNA) blot analysis indicated that the e...

Traditional rice cultivars in Sri Lanka conserve different abiotic and biotic tolerant traits but the yield of traditional rice cultivars is not as much of improved cultivars. Abiotic stress tolerance of some traditional rice cultivars were evaluated in previous studies at Faculty of Agriculture, Mapalana, Sri Lanka and this study attempted to understand the possibility of enhancing the yield a...

Quantitative and qualitative changes in total leaf soluble proteins were determined in a spring cv. Zagross and in a winter cv. Azar 2 cultivar of allohexaploid wheat (Triticum aestivum L.) exposed to 4°C for two weeks. The data obtained were used to test whether these different genotypes of wheat responded differentially to cold treatment. Seedlings were grown in a controlled growth chamber fo...

The effects of exogenously applied silicon (Si) on plant growth and the isoform patterns of NAD-dependent malate dehydrogenase (NAD-MDH, EC 1.1.1.37) and NADPdependent malic enzyme (NADP-ME, EC 1.1.1.40) were studied in two pea genotypes (cultivar Auralia and mutant line 1/220) subjected to differential Mn treatments (50, 200 and 500 μM Mn) under control conditions. The excess Mn inhibited plan...

Fusarium head blight (FHB) is a serious disease of wheat worldwide. Cultivar resistance to FHB depends on biochemical factors that confine the pathogen spread in spikes. Breeding for cultivar resistance is considered the most practical way to manage this disease. In this study, different spectroscopy and microscopy techniques were applied to discriminate resistance in wheat genotypes against FH...

BACKGROUND AND AIMS Sunflower cultivars exhibit a wide range of oil content in the mature achene, but the relationship between this and the dynamics of oil deposition in the achene during grain filling is not known. Information on the progress, during the whole achene growth period, of the formation of oil bodies in the components of the achene and its relationship with variations in final oil ...

Recent evidence indicates a role for calcium and calmodulin in the gravitropic response of primary roots of maize (Zea mays, L.). We examined this possibility by testing the relationship between calmodulin activity and gravitropic sensitivity in roots of the maize cultivars Merit and B73 x Missouri 17. Roots of the Merit cultivar require light to the gravitropically competent. The gravitropi...

The perennial grass species that are being developed as biomass feedstock crops harbor extensive genotypic diversity, but the effects of this diversity on biomass production are not well understood. We investigated the effects of genotypic diversity in switchgrass (Panicum virgatum) and big bluestem (Andropogon gerardii) on perennial biomass cropping systems in two experiments conducted over 20...

Salinity is a phenomenon challenging the plantation and growth of grape in arid and semiarid regions. During the present research, tolerance of two grape cultivars (Soltanin and Fakhri) was evaluated against various sodium chloride salinity levels (zero, 50, 100, 150, 200 and 250 mM), which was conducted based on factorial experiment in the form of Randomized Complete Design (RCD) with three re...

BACKGROUND Leafcutter ants depend on the cultivation of symbiotic Attamyces fungi for food, which are thought to be grown by the ants in single-strain, clonal monoculture throughout the hundreds to thousands of gardens within a leafcutter nest. Monoculture eliminates cultivar-cultivar competition that would select for competitive fungal traits that are detrimental to the ants, whereas polycultu...