Phenotypic and Molecular Assessment of Wheat Genotypes Tolerant to Leaf Blight,Rust and Blast Diseases

Globally among biotic stresses, diseases like blight, rust and blast constitute prime constraints for reducing wheat productivity especially in Bangladesh. For sustainable productivity, the development of disease-resistant lines and high yielding varieties is vital and necessary. This study was conducted using 122 advanced breeding lines of wheat including 21 varieties developed by Bangladesh Wheat and Maize Research Institute (BAMRI) with aims to identify genotypes having high yield potential and resistance to leaf blight, leaf rust and blast diseases. These genotypes were evaluated for resistance against leaf blight and leaf rust at Dinajpur and wheat blast at Jashore under field condition. Out of 122 genotypes tested, 20 lines were selected as resistant to leaf blight based on the area under the diseases progress curve (AUDPC) under both irrigated timely sown (ITS) and irrigated late sown (ILS) conditions. Forty-two genotypes were found completely free from leaf rust infection, 59 genotypes were identified as resistant, and 13 genotypes were identified as moderately resistant to leaf rust. Eighteen genotypes were immune against wheat blast, 42 genotypes were categorized as resistant, and 26 genotypes were identified as moderately resistant to wheat blast. Molecular data revealed that the 16 genotypes showed a positive 2NS segment among the 18 immune genotypes selected against wheat blast under field conditions. The genotypes BAW 1322, BAW 1295, and BAW 1203 can be used as earlier maturing genotypes and the genotypes BAW 1372, BAW 1373, BAW 1297 and BAW 1364 can be used for lodging tolerant due to short plant height. The genotypes WMRI Gom 1, BAW 1349 and BAW 1350 can be selected for bold grain and the genotypes WMRI Gom 1, BAW 1297, BAW 1377 can be used as high yielder for optimum seeding condition but genotypes BAW 1377 and BAW 1366 can be used for late sown condition. The selected resistant genotypes against specific diseases can be used in the further breeding program to develop wheat varieties having higher disease resistance and yield potential.     

Contrasting Effects of Farmyard Manure (FYM) and Compost for Remediation of Metal Contaminated Soil

We investigated effect of farm yard manure (FYM) and compost applied to metal contaminated soil at rate of 1% (FYM-1, compost-1), 2% (FYM-2, compost-2), and 3% (FYM-3, compost-3). FYM significantly (P < 0.001) increased dry weights of shoots and roots while compost increased root dry weight compared to control. Amendments significantly increased nickel (Ni) in shoots and roots of maize except compost applied at 1%. FYM-3 and -1 caused maximum Ni in shoots (11.42 mg kg^?1) and roots (80.92 mg kg^?1), respectively while compost-2 caused maximum Ni (14.08 mg kg^?1) and (163.87 mg kg^?1) in shoots and roots, respectively. Plants grown in pots amended with FYM-2 and compost-1 contained minimum Cu (30.12 and 30.11 mg kg^?1) in shoots, respectively. FYM-2 and compost-2 caused minimum zinc (Zn) (59.08 and 66.0 mg kg^?1) in maize shoots, respectively. FYM-2 caused minimum Mn in maize shoots while compost increased Mn in shoots and roots compared to control. FYM and compost increased the ammonium bicarbonate diethylene triamine penta acetic acid (AB-DTPA) extractable Ni and Mn in the soil and decreased Cu and Zn. Lower remediation factors for all metals with compost indicated that compost was effective to stabilize the metals in soil compared to FYM.     

Neuronal expression of a single‐subunit yeast NADH–ubiquinone oxidoreductase (Ndi1) extends Drosophila lifespan

The ‘rate of living’ theory predicts that longevity should be inversely correlated with the rate of mitochondrial respiration. However, recent studies in a number of model organisms, including mice, have reported that interventions that retard the aging process are, in fact, associated with an increase in mitochondrial activity. To better understand the relationship between energy metabolism and longevity, we supplemented the endogenous respiratory chain machinery of the fruit fly Drosophila melanogaster with the alternative single‐subunit NADH–ubiquinone oxidoreductase (Ndi1) of the baker’s yeast Saccharomyces cerevisiae. Here, we report that expression of Ndi1 in fly mitochondria leads to an increase in NADH–ubiquinone oxidoreductase activity, oxygen consumption, and ATP levels. In addition, exogenous Ndi1 expression results in increased CO₂ production in living flies. Using an inducible gene‐expression system, we expressed Ndi1 in different cells and tissues and examined the impact on longevity. In doing so, we discovered that targeted expression of Ndi1 in fly neurons significantly increases lifespan without compromising fertility or physical activity. These findings are consistent with the idea that enhanced respiratory chain activity in neuronal tissue can prolong fly lifespan.     

Establishment and coexistence of two predators,Laricobius nigrinus and Sasajiscymnus tsugae,introduced against hemlock woolly adelgid on eastern hemlock

The coexistence of two introduced predatory species, Laricobius nigrinus Fender and Sasajiscymnus tsugae (Sasaji and McClure), and a native predator, L. rubidus LeConte, on eastern hemlock was documented for the first time. Details of their coexistence and implications to management of hemlock woolly adelgid, Adelges tsugae Annand, are discussed.     

Catecholamines up integrates dopamine synthesis and synaptic trafficking

The highly reactive nature of dopamine renders dopaminergic neurons vulnerable to oxidative damage. We recently demonstrated that loss-of-function mutations in the Drosophila gene Catecholamines up (Catsup) elevate dopamine pools but, paradoxically, also confer resistance to paraquat, an herbicide that induces oxidative stress-mediated toxicity in dopaminergic neurons. We now report a novel association of the membrane protein, Catsup, with GTP cyclohydrolase rate-limiting enzyme for tetrahydrobiopterin (BH(4)) biosynthesis and tyrosine hydroxylase, rate-limiting enzyme for dopamine biosynthesis, which requires BH(4) as a cofactor. Loss-of-function Catsup mutations cause dominant hyperactivation of both enzymes. Elevated dopamine levels in Catsup mutants coincide with several distinct characteristics, including hypermobility, minimal basal levels of 3,4-dihydroxy-phenylacetic acid, an oxidative metabolite of dopamine, and resistance to the vesicular monoamine transporter inhibitor, reserpine, suggesting that excess dopamine is synaptically active and that Catsup functions in the regulation of synaptic vesicle loading and release of dopamine. We conclude that Catsup regulates and links the dopamine synthesis and transport networks.     

Bioassay of insulin activity of pancreatic tissue in active and aestivated African lungfish, Protopterus annectens (Owen)

The insulin activity of the pancreatic tissues of free-swimming and aestivated African lungfish, P. annectens (Owen), was bioassayed against standard insulin in rabbits. The hepatic glycogen content and plasma glucose concentration in free-swimming and aestivated lungfish were also estimated. The liver glycogen content was 64·47 ± 6·32 and 7·19 ± 2·68 mgg⁻¹ net wt and the plasma glucose concentration was 37·62 ± 4·22 and 6·39 ± 1·29% in free-swimming and aestivated lungfish, respectively.
Extracts of pancreatic tissue of the lungfish produced a dose-dependent decrease in the plasma glucose concentration in rabbits. The magnitude of the decrease in plasma glucose concentration produced by extracts from aestivated specimens was significantly smaller (about 26%) compared to that produced by pancreatic extracts from free-swimming active lungfish (about 37%). The insulin activity of the pancreatic tissue was 0·82 ± 0·02 and 1·27 ± 0·25 iu mg⁻¹ dry pancreatic tissue weight in aestivated and free-swimming lungfish, respectively.     

Extraction, purification, identification and metabolism of 3'',5''-cyclic UMP, 3'',5''-cyclic IMP and 3'',5''-cyclic dTMP from rat tissues.

The large-scale extraction and partial purification of endogenous 3',5'-cyclic UMP, 3',5'-cyclic IMP and 3',5'-cyclic dTMP are described. Rat liver, kidney, heart, spleen and lung tissues were subjected to a sequential purification procedure involving freeze-clamping, perchlorate extraction, alumina and Sephadex ion-exchange chromatography and preparative electrophoresis. The samples thus obtained co-chromatographed with authentic cyclic UMP, cyclic IMP and cyclic dTMP on t.l.c. and h.p.l.c. and the u.v. spectra of the extracted samples were identical with those of the standards. Fast atom bombardment of the three cyclic nucleotide standards yielded mass spectra containing a molecular protonated ion in each case; mass-analysed ion kinetic-energy spectrometry ('m.i.k.e.s') of these ions produced a spectrum unique to the parent cyclic nucleotide. The extracted putative cyclic UMP, cyclic IMP and cyclic dTMP each produced a m.i.k.e.s. identical with that obtained with the corresponding cyclic nucleotide standard. Rat liver, heart, kidney, brain, intestine, spleen, testis and lung protein preparations were each found capable of the synthesis of cyclic UMP, cyclic IMP and cyclic dTMP from the corresponding nucleoside triphosphate, of the hydrolysis of these cyclic nucleotides and of their binding, with the exception that cyclic dTMP was not synthesized by the kidney preparation.     

Regucalcin ameliorates doxorubicin-induced cytotoxicity in Cos-7 kidney cells and translocates from the nucleus to the mitochondria

Doxorubicin (DOX) is a potent anticancer drug, which can have unwanted side-effects such as cardiac and kidney toxicity. A detailed investigation was undertaken of the acute cytotoxic mechanisms of DOX on kidney cells, using Cos-7 cells as kidney cell model. Cos-7 cells were exposed to DOX for a period of 24 h over a range of concentrations, and the LC₅₀ was determined to be 7 µM. Further investigations showed that cell death was mainly via apoptosis involving Ca²⁺ and caspase 9, in addition to autophagy. Regucalcin (RGN), a cytoprotective protein found mainly in liver and kidney tissues, was overexpressed in Cos-7 cells and shown to protect against DOX-induced cell death. Subcellular localization studies in Cos-7 cells showed RGN to be strongly correlated with the nucleus. However, upon treatment with DOX for 4 h, which induced membrane blebbing in some cells, the localization appeared to be correlated more with the mitochondria in these cells. It is yet to be determined whether this translocation is part of the cytoprotective mechanism or a consequence of chemically induced cell stress.