Genetic necrosis in Triticum × aegilops pentaploid hybrids

Summary Ten varieties of Triticum aestivum and three synthetic T. durum + Aegilops squarrosa hexaploids were crossed with an Ae. bicornis + Ae. squarrosa amphiploid. 55 hybrid plants involving 9 different combinations developed necrosis and died before maturity. The two plants which survived were both from the F₁ with a synthetic hexaploid, T. durum var. Carleton + Ae. squarrosa.The genetic necrosis developing in these hybrids differed from hybrid necrosis and red hybrid chlorosis both in symptoms and in the genetic basis. The symptoms were similar to those reported for a number of Triticum x Aegilops hybrids in which Ae. bicornis and Ae. squarrosa were involved but the genetic basis was not determined. The survival of 2 of the 13 progenies from one cross is discussed.

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Adjuvanted Outer Membrane Protein Vaccine Protects Poultry against Infection with Salmonella enteritidis

The immunogenicity of a sonicated extract (SE) and of outer membrane proteins (OMP) of Salmonella enteritidis was tested in birds of about 8 weeks of age. The dose, route of vaccination and the adjuvant used varied in different groups of birds. Two vaccine doses with or without adjuvant were given parenterally or orally 3 weeks apart. OMP vaccines gave significantly higher antibody titres than SE vaccines, as indicated by ELISA. The vaccines adjuvanted with oil produced higher antibody titres than those without any adjuvant. A dose of 1 mg of vaccine produced higher antibody titres than 0.5 mg of vaccine. Adjuvanted vaccine given subcutaneously elicited higher antibody responses than oral vaccines given without adjuvant. The birds were challenged with virulent S. enteritidis organisms at the end of the second week after a booster dose. None of the birds given 1 mg of OMP vaccine subcutaneously shed the organisms when tested by culturing cloacal swabs, although a few birds vaccinated with 0.5 mg of OMP vaccine did so. In general, adjuvanted OMP vaccines gave better protection than SE vaccines.     

Synthesis and fungicidal activity of novel 4,4'-bis(2' '-aryl-5' '-methyl/unsubstituted-4' '-oxo-thiazolidin-3' '-yl) bibenzyl

Reduction followed by nitration of benzil I yielded 4,4'-dinitrobibenzyl (III) which by reduction furnished quantitatively and analytically pure 4,4'-diaminobibenzyl (IV) which on condensation with different carbonyl compounds gave 4,4'-bis (benzylideneamino) bibenzyls (Va-f). Compounds (Va-f) on cycloaddition with mercaptoacetic acid/2-mercaptopropionic acid yielded the corresponding 4-oxothiazolidin-3-yl bibenzyls (VIa-l). The compounds VIg-l have two chiral centers in each thiazolidinone moiety so two diastereomers are possible, but on crystallization and repeated chromatography, one diastereomer was obtained. The absolute configuration of the diastereomer was tentatively assigned on the basis of (1)H NMR spectra. (1)H NMR spectra of the product showed a distinct doublet at delta 1.22 for C(5)-CH(3) of thiazolidinone ring (22, 23) and a distinct quartet at delta 4.20 for the C(5)-H proton. Similarly, the C(2) proton showed an independent singlet at delta 5.95, so the diastereomers obtained were assigned trans configuration. Compounds Va-f and VIa-l were evaluated in vitro for their fungitoxicities against Fusarium oxysporium and Penicillium citrinum. All the compounds were found to be antifungal active. Some of the compounds displayed activities comparable with that of the commercial fungicide Dithane M-45. Structure-activity relationships for the screened compounds are discussed.     

Performance and selection for yield of wheat mutants derived from different cultivars

Summary Phenotypically stable wheat mutants derived from the gamma rays, ethyl methane sulphonate and combined mutagenic treatments of one locally bred cultivar (C-591) and two cultivars (Indus-66 and Nayab) of Mexican origin, were tested for yield performance in M₆ generation. Mutants originating from Nayab could be classified into two main categories relative to the control viz. significantly higher yielding and significantly lower yielding. Mutants of C-591 and Indus-66 gave only significantly reduced mean yields compared with their respective controls. Considerable increases in genotypic variance, heritability and genetic gain expected from selection, were observed among the mutants of the three cultivars. The importance of induced mutations for increasing genetic variability connected with useful agronomic traits is emphasised.     

The phytotoxicity and degradation of diesel hydrocarbons in soil

Hydrocarbon contamination in soils may be toxic to plants and soil microorganisms and act as a source of groundwater contamination. The objective of the study was to evaluate the fate of adding diesel in soil with no previous history of hydrocarbon contamination. Particular aspects examined were soil respiration, changes in microbial population, breakdown of diesel hydrocarbon and phytotoxicity to germination of ryegrass. Soil respiration was measured as evolved CO₂. Bacterial population was determined as Colony Forming Units (CFUs) in dilution plates, and fungal activity was measured as hyphal length. The fate of individual hydrocarbons was determined by GC‐MS after extraction with dichloromethane. When 0.64 % (w/w) of diesel was added to soil, the respiration response showed a lag phase of 2 days and maximum respiration occurred at day 7. The lag phase was 5 days and maximum respiration occurred at day 11 in soil after adding 1.6 %, 4.0 %, and 13.6 % of diesel (w/w). After the peak, respiration decreased up to 20 days, in each of the four levels of diesel addition to the soil. Thereafter, respiration becomes more or less constant but substantially greater than the control. Diesel addition up to 4.0 % (w/w) increased the bacterial population to 10 fold but fungal hyphal length did not increase. However, bacterial population did not increase after adding 13.6 % (w/w) of diesel and fungal hyphal length was significantly less than the control and other three levels of diesel. Removal of inhibition to germination of perennial ryegrass was linked to the decomposition of n‐C₁₀ and n‐C₁₁ hydrocarbons and took from 11 to 30 days depending on the levels of diesel added to the soil. Contamination with 13.6 % (w/w) of diesel inhibited the germination of perennial ryegrass until 24 weeks of incubation.     

Vegetation-environment relationships in the forests of Chitral district Hindukush range of Pakistan

We investigated the composition of plant communities to quantify their relationships with environmental parameters in the Chitral Hindukush range of Pakistan. We sampled tree vegetation using the Point Centered Quarter (PCQ) method while understory vegetation was sampled in 1.5-m circular quadrats. Cedrus deodara is the national symbol of Pakistan and was dominant in the sampled communities. Because environmental variables determine vegetation types, we analyzed and evaluated edaphic and topographic factors. DCA-Ordination showed the major gradient as an amalgam of elevation (p<0.05) and slope (p<0.01) as the topographic factors correlated with species distribution. Soil variables were the factors of environmental significance along DCA axes. However, among these factors, Mg2+ , K + and N2+ contributed not more than 0.054% 0.20% and 0.073%, respectively, to variation along the first ordination axis. We conclude that the principal reason for weak or no correlation with many edaphic variables was the anthropogenic disturbance of vegetation. The understory vegetation was composed of perennial herbs in most communities and was most dense under the tree canopy. The understory vegetation strongly regulates tree seedling growth and regeneration patterns. We recommend further study of the understory vegetation using permanent plots to aid development of forest regeneration strategies.     

Anti-stress properties and two HSP70s mRNA expressions of blunt snout bream (Megalobrama amblycephala) fed with all-plant-based diet

The influence of all-plant-based diet on fingerling blunt snout breams (Megalobrama amblycephala) was tested by examining growth performance, anti-stress properties and related gene expression. Healthy fish were randomly divided into triplicate groups per dietary treatment and fed with different formulated diets. The results showed that both weight gain, specific growth rate and protein efficiency ratio of all-plant-based diet group were significant higher than those of the control (p < 0.05). In contrast, FCR of all-plant-based diet group was significantly lower than that of the control (p < 0.05). Therefore, all-plant-based diets could not affect the growth performance of blunt snout breams. Compared to the control group, the lysozyme levels in serum and mucus, and glutamic-oxaloacetic transaminase activities in serum and liver decreased significantly (p < 0.05). In contrast, the glutamic-pyruvic transaminase activities in serum and liver increased significantly (p < 0.05). For blunt snout breams fed with all-plant-based diets, the superoxide dismutase activities in mucus, serum and liver as well as catalase activity in serum and liver were decreased significantly (p < 0.05) comparing with that of the control group. But malondialdehyde contents were higher (p < 0.05) in serum and liver than that of control group. The expression of HSC70 mRNA increased significantly (p < 0.05) in blunt snout breams fed with all-plant-based diet, whereas the HSP70 mRNA expression decreased significantly (p < 0.05) when compared with control group. In conclusion, all these results indicated that the application of all-plant-based diet could decrease the anti-stress properties (non-specific immunity, stress resistance and antioxidant ability) and HSP70 mRNA expression in blunt snout breams fingerling. Although all-plant-based diets could not affect the growth performance of blunt snout breams, the application of all-plant-based diet should be discreet in the production practice.     

Cumulative Effect of Soil and Foliar Application of Nitrogen,Phosphorus, and Sulfur on Growth,Physico-Biochemical Parameters,Yield Attributes,and Fatty Acid Composition in Oil of Erucic Acid-Free Rapeseed-Mustard Genotypes

ABSTRACT

The feasibility of split (soil + foliar) applications of nitrogen (N) and phosphorus (P) and addition of a small quantity of sulfur (S) in the spray was tested for improving performance of rapeseed-mustard genotypes in a factorial randomized field experiment. Three genotypes (two erucic acid free, viz. Brassica napus L. cv. ‘Hyola PAC – 401’ and Brassica juncea L. Czern. and Coss. cv. ‘TERI (0E) M 21-Swarna’, and one best performing high yielding Brassica juncea L. cv. ‘Rohini’ as a check) were grown with four soil (B) plus foliar (F) applications of N, P, and S with uniform basal 30 kg potassium (K) ha^{? 1} (K₃₀), viz. (i) the optimum soil-applied treatment supplemented with the spray of deionized water (B_N90P30 + Fw) comprising control, (ii) B_N70P30 + F _N20, (iii) B_N70P28 + F_N20P2, and (iv) B_N70P28 + F_N20P2S2. Soil Plus foliar application of nutrients, particularly B_N70P28 + F_N20P2S2, improved their performance with respect to growth characteristics (shoot length plant^{? 1}, leaf number plant^{? 1}, area leaf^{? 1}, leaf area index, fresh weight plant^{? 1}, and dry weight plant^{? 1}), physico-biochemical parameters (net photosynthetic rate, stomatal conductance, carboxylation efficiency, water use efficiency, carbonic anhydrase activity, leaf NPK content, and N use efficiency), yield attributes (pod number plant^{? 1}, seed number pod^{? 1}, 1000-seed weight, seed yield ha^{? 1}, oil content, and oil yield ha^{? 1}), and fatty acid composition in oil of these genotypes. The cultivar ‘Hyola PAC-401’ performed best particularly with B_N70P28 + F_N20P2S2. The improvement in the response of genotypes to the split application of nutrients may be attributed to their ready availability through foliar application.     

Wheat Breeding in a Water-stressed Environment. I. Delineation of Drought Tolerance and Susceptibility

To elucidate genotypic differences expressed through the grain yield of drought-stressed wheat, 21 commercial varieties and advanced lines were evaluated in the field under a range of soil water levels to induce varying degrees of drought stress. This paper presents data on grain yield and yield-based indices to indicate drought tolerance and drought susceptibility. AZS-4 was identified as drought tolerant and AZS-17 and ‘Pavon’ as drought susceptible. High gram yield under stress can be explained in terms of high yield potential, thus grain yield proved to be the best indicator of drought tolerance.