Effect of increased CO2 concentration and temperature on the phyllosphere mycoflora of winter wheat flag leaves during ripening

The impact of elevated carbon dioxide (CO₂, 600/700 μmol mol^-1) and temperature (+ 4°C) on phyllosphere fungi colonising flag leaves of mini crops of winter wheat cv. Mercia between anthesis and harvest was determined in a computer-controlled environment facility in 1993 and 1994. In both years the total fungal populations (cm² leaf) were found to have increased due to exposure to either elevated CO₂ and elevated CO₂+ temperature treatments. This was mainly due to significant increases in populations of Cladosporium spp. (C. cladosporioides and C. herbarum) on the flag leaves during ripening. Other phyllosphere component species such as white and pink yeasts were not markedly affected by treatments. The range of fungal species found in such controlled environment chambers was narrower than that commonly found on flag leaves of field grown crops. Common and important colonisers of leaves and ripening ears such as Aureobasidium pullulans, Epicoccum nigrum and Fusarium spp. were seldom isolated.     

Construction of intersubspecific molecular genetic map of lentil based on ISSR, RAPD and SSR markers

Lentil (Lens culinaris ssp. culinaris), is a self-pollinating diploid (2n?=?2x?=?14), cool-season legume crop and is consumed worldwide as a rich source of protein (~24.0%), largely in vegetarian diets. Here we report development of a genetic linkage map of Lens using 114 F₂ plants derived from the intersubspecific cross between L 830 and ILWL 77. RAPD (random amplified polymorphic DNA) primers revealed more polymorphism than ISSR (intersimple sequence repeat) and SSR (simple sequence repeat) markers. The highest proportion (30.72%) of segregation distortion was observed in RAPD markers. Of the 235 markers (34 SSR, 9 ISSR and 192 RAPD) used in the mapping study, 199 (28 SSRs, 9 ISSRs and 162 RAPDs) were mapped into 11 linkage groups (LGs), varying between 17.3 and 433.8 cM and covering 3843.4 cM, with an average marker spacing of 19.3 cM. Linkage analysis revealed nine major groups with 15 or more markers each and two small LGs with two markers each, and 36 unlinked markers. The study reported assigning of 11 new SSRs on the linkage map. Of the 66 markers with aberrant segregation, 14 were unlinked and the remaining 52 were mapped. ISSR and RAPD markers were found to be useful in map construction and saturation. The current map represents maximum coverage of lentil genome and could be used for identification of QTL regions linked to agronomic traits, and for marker-assisted selection in lentil.     

In vitro assessment of cord blood–derived proinsulin-specific regulatory T cells for cellular therapy in type 1 diabetes

Background

Antigen-specific regulatory T cells (Tregs) have proven to be effective in reversing established autoimmunity in type 1 diabetes (T1D). Cord blood (CB) can serve as an efficient and safe source for Tregs for antigen-specific immunomodulation in T1D, a strategy that is yet to be explored. Therefore, we assessed the potential of CB in generation of proinsulin (PI)-specific Tregs by using HLA class II tetramers.

Effect of high temperature treatment on disinfestation and quality characteristics of sorghum

Sorghum grain (two varieties) was modified to different water contents (12% to 16% wet weight basis) and heated to 60°C, 70°C and 80°C for periods of 4, 8 and 12 min. Germination, seedling vigour, seedling dry matter, free fatty acid (FFA) content, fungal contamination and infestation with the insect pest Rhyzopertha dominica (F.) were all markedly affected by heat treatment. The effectiveness of the heat treatment was also influenced by the size of the sample used. Heat treatment at 60°C and 70°C resulted in germination being unaffected or stimulated while at 80°C and the higher water contents significantly reduced, when compared to untreated controls. The dry matter of seedlings, and seedling vigour was positively correlated with germination and heat treatment. Heat treatment had no effect on FFA. All stages of the insect pest, R. dominica, were destroyed at 70°C and an 8 min exposure time. However, the water content of the sorghum was critical in determining the efficacy against this pest. The percentage fungal contamination of grain was reduced from 90% to about 25% by heat treatment. However, some grain fungi, particularly Eurotium spp., Aspergillus niger and Penicillium spp. could still be isolated from sorghum grain treated at 80°C for up to 12 minutes.