Subcortical brain atrophy persists even in HAART-regulated HIV disease

The purpose of this study was to determine the pattern and extent of caudate nucleus and putamen atrophy in HIV-infected men with well-controlled immune status and viral replication. 155 men underwent structural brain magnetic resonance imaging; 84 were HIV-infected and 71 were uninfected controls. MRI data were processed using the Fully Deformable Segmentation routine, producing volumes for the right and left caudate nucleus and putamen, and 3-D maps of spatial patterns of thickness. There was significant atrophy in the HIV-infected men in both the caudate and putamen, principally in the anterior regions. The volume of the basal ganglia was inversely associated with the time since first seropositivity, suggesting that either there is a chronic, subclinical process that continues in spite of therapy, or that the extent of the initial insult caused the extent of atrophy

STS marker based tracking of slow rusting <i>Lr34</i> gene in Indian wheat genotypes

207-213Bi-allelic STS marker was used to confirm the presence of adult plant durable rust resistance gene Lr34 in advance generation breeding lines. These lines were scored for leaf rust three times at an equal interval and the area under disease progress curve (AUDPC) was calculated. The lower AUDPC values of Lr34 positive lines confirmed their slow rusting nature. In the absence of direct selection method, the breeders are selecting Lr34 gene carrying lines unintentionally as they showed better resistance. Lines possessing Lr34, an ‘undefeated gene’, should be used in breeding programme in order to have a broad-spectrum durable leaf rust resistance

Plant Archives

Not AvailableThe antagonistic potential of bacteria is being applied to biocontrol the infectious diseases caused by pathogenic fungi in plants that are one of the major threats to the growth and productivity of crop plants. In the present study, bacterial strains were isolated from soil samples collected from the rhizosphere of Sorghum (Sorghum bicolor) and Wheat (Triticum aestivum). Microscopic analysis revealed that all three bacterial isolates were Gram-positive, rod-shaped and spore-forming. The isolates Bacillus subtilis BP171 and Bacillus amyloliquefaciens BP124 demonstrated salt tolerance up to 12% while Bacillus subtilis BP67 tolerated up to 10% of NaCl. All the three strains were screened against seven test pathogenic fungi like Bipolaris sorokiniana, Fusarium oxysporum, Aspergillus sp., Penicillium sp., Rhizoctonia solani, Aspergillus niger, and Fusarium sp. for their antagonistic activity. BP124 was found to be the most potent in comparison to BP67 and BP171. Bacillus amyloliquefaciens BP124 demonstrated significantly highest (p<.0001) inhibition percentage against Fusarium sp., (61%) and Fusarium oxysporum (60%). The optimization of various parameters like pH, temperature, inoculum size, agitation, carbon sources, and nitrogen sources was carried out to enhance the antagonistic potential of bacterial isolates. The results revealed that the bacterial isolates were able to demonstrate significantly highest (p<.0001) antagonistic potential when inoculum size required for the growth was 1ml, agitation rate at 150 rpm, while the medium of pH at 7.0 and 30oC incubation temperature. Starch as carbon source and peptone as nitrogen source supported significantly highest (p<.0001) antagonistic activity against all the fungal pathogens for all the bacterial isolates. Therefore, the study showed that appropriate and optimum fermentation conditions can be of great importance in enhancing the antagonistic potential of bacterial isolates

Marker-Assisted Improvement of Bread Wheat Variety HD2967 for Leaf and Stripe Rust Resistance

The mega wheat variety HD2967 was improved for leaf and stripe rust resistance by marker-assisted backcross breeding. After its release in 2011, HD2967 became susceptible to stripe rust and moderately susceptible to leaf rust. The leaf rust resistance gene LrTrk was transferred into HD2967 from the durum wheat genotype Trinakria. Then, HD2967 was crossed with Trinakria to produce F1 plant foreground selection for LrTrk and background selection for the recurrent parent genotype was carried out in BC1F1, BC2F1 and BC2F2 generations. Foreground selection was carried out with the linked marker Xgwm234, while polymorphic SSR markers between parents were used for background selection. Background selection resulted in the rapid recovery of the recurrent parent genome. A morphological evaluation of 6 near isogenic lines (NILs)—2 resistant to leaf and stripe rust, and 4 resistant to leaf rust only—showed no significant differences in yields among NILs and the recurrent parent HD2967. All of the 6 NILs showed the presence of 2NS/2AS translocation, carrying the linked genes Lr37/Sr38/Yr17 present in HD2967 and the targeted leaf rust resistance gene LrTrk. Two NILs also showed additional resistance to stripe rust. Therefore, these NILs with rust resistance and an at par yielding ability of H2967 can replace the susceptible cultivar HD2967 to reduce yield losses due to disease

Native rhizobacteria suppresses spot blotch disease, improves growth and yield of wheat under salt–affected soils

The simultaneous occurrence of biotic and abiotic stresses affects the performance of the crops in salt–affected agroecologies. The plant–microbe interaction with effective rhizobacteria can effectively manage these stresses. This study characterized the biocontrol, plant growth promotion, and responsiveness of rhizobacteria in wheat under salt-affected soils. Out of the 184 rhizobacteria isolates, the 20 isolates showed 41–72% growth inhibition of fungal phytopathogens of seedling blight of wheat (Fusarium sp), head blight of wheat (Fusarium oxysporum), onion molds (Penicillium sp and Aspergillus sp), root rot of wheat (Rhizoctonia solani), ear rot of corn (Aspergillus sp.) and spot blotch of wheat (Bipolaris sorokininana). The potent three rhizobacterial isolates identified as close neighbours of Bacillus amyloliquefaciens strain TA124, B. subtilis strain SB67 and B. subtilis strain BJ171 caused 65.5–71.1% growth inhibition of B. sorokiniana. The extracellular organic acid, siderophore, and chitinase enzymes played a significant role in rhizobacterial performance for fungal growth inhibition; and P and Zn solubilization in growth media. The foliar spray of bioformulation aids 15–20% reduction in the B. sorokiniana disease severity. The rhizobacterial responsiveness to the dual inoculation through seed treatment and foliar spray was 12.6–51, 15.8–46.3, and 13.2–148.1% for grain yield, P uptake, and disease suppression, respectively. The changes caused by rhizobacterial bioformulation in soil (Olsen's–P and microbial biomass carbon) and plant (proline, malondialdehyde, peroxidase, and Na+/K+ratio) explained 85% variability in the yield, P nutrition, and disease severity. Therefore, native rhizobacteria with biocontrol and plant growth-promoting capabilities can be an effective option for managing multiple stresses of crops in salt–affected agroecologies