Effect of Sanitizers on Planktonic Edwardsiella tarda Isolated from Asian Stinging Catfish Heteropneustes fossilis (Bloch 1794)

Incidence of Edwardsiella tarda in Asian stinging catfish, Heteropneustes fossilis (Bloch), and its sensitivity to antibiotics and sanitizers was studied. Five out of 10 representative lots of H. fossilis were positive for E. tarda. The minimum bactericidal concentration (MBC) of sanitizers (hydrogen peroxide, glutaraldehyde, benzalkonium chloride, sodium hypochlorite, and iodophor) on planktonic E. tarda varied with strains, suspending media (distilled water, physiological saline, pond water, and tryptic soy broth), and combination of factors. The time taken by the sanitizers to achieve 5-log reductions varied greatly between 1 min and 180 min at X and 2X MBCs of sanitizers. Benzalkonium chloride, glutaraldehyde, and sodium hypochlorite were effective in reducing the planktonic E. tarda at concentrations ranging from 3.13 ppm for glutaraldehyde to 25 ppm for sodium hypochlorite. Edwardsiella tarda strains were highly sensitive to ciprofloxacin and exhibited varying degrees of resistance to other antibiotics.     

Early Stage above Ground Interaction in Wheat-Jatropha Agrisilviculture System

Experiments were conducted to analyze the initial tree crop interaction between Jatropha curcas and wheat by planting the perennial component in East-West orientation with 8-2 m distance and wheat as intercrop at National Research Centre for Agroforestry （NRCAF）, Jhansi during July, 2007 to April, 2009. During planting of Jatropha the interaction to wheat was non-significant and influence of orientation is also nil. Eighteen months after plating Jatropha had attained the mean height of 124.56 cm, collar diameter of 6.37 cm, number of branches of 11.25, canopy diameter of 98.5 cm and yielded 18.5 g seeds per plant. During 18 MAP also observations revealed the non-significant influence of Jatropha on wheat. Observations also indicated the progress in wheat growth and yield attributes with the increase of distances from tree base and it follow the order of 0.5 m〈1.0 m〈2.0 m〈3.0, 4.0 m and open. Nearly, 62% and 14% yield loss in wheat grain was observed at 0.5 m and lm distance from the tree base respectively compare with open. Comparison ofwheat-Jatropha agrisilviculture system and sole wheat cropping indicated the net grain yield reduction up to 13.5% by agrisilviculture system. The comparison of wheat and straw yields between the two years clearly indicating that the system and sole cropping have not much differed while the influence of climatic factor is witnessed by the variation of yields over years. It revealed that the initial above ground interaction between Jatropha and wheat was due to the space that can be managed by the pruning of branches which is a recommended cultural practice of Jatropha.     

Morphological,cytological and reproductive characterization of tri-species hybrids (GOS) between <Emphasis Type="Italic">Pennisetum glaucum</Emphasis>, <Emphasis Type="Italic">P. orientale</Emphasis> and <Emphasis Type="Italic">P. squamulatum</Emphasis>

New tri-species hybrids (GOS) in the genus Pennisetum involving the cultivated species pearl millet (P. glaucum L.) and two wild species, viz. P. squamulatum Fresen and P. orientale L. C. Rich, are reported. Six hybrid plants were recovered after crossing a backcross hybrid (2n = 3x = 23, GGO) between P. glaucum (2n = 2x = 14, GG) and P. orientale (2n = 2x = 18, OO) with F₁s (2n = 6x = 42, GGSSSS) between P. glaucum (2n = 4x = 28, GGGG) and P. squamulatum (2n = 8x = 56, SSSSSSSS). The hybrids were perennial, morphologically intermediate to their parents, and represented characters from the three contributing species. The hybrids contained 2n = 44 chromosomes (GGGSSO) representing 21, 14 and nine chromosomes from P. glaucum, P. squamulatum and P. orientale, respectively. Meiotic and flow-cytometric analysis suggested origin of these hybrids from unreduced female and reduced male gametes. Average chromosome configuration (8.42_I + 14.32_II + 1.62_III + 0.52_IV) at Meiosis showed limited inter-genomic pairing indicating absence of significant homology between the three genomes. The hybrids were male sterile (except one) and highly aposporous. P. orientale was identified to induce apospory in hybrid background with P. glaucum at diploid and above levels, though it was quantitatively affected by genomic doses from sexual parent. A case of inducible and recurrent apospory is presented whereby a transition from Polygonum-type sexual embryo-sacs to Panicum-type aposporous embryo-sacs was observed in diploid interspecific hybrids. Results supported independent origin and partitioning of the three apomixis-components (apomeiosis, parthenogenesis, and functional endosperm development), reported for the first time in Pennisetum. Potential utilization of GOS hybrids in understanding genome interactions involved in complex traits, such as perenniality and apomixis, is discussed.     

Sources of resistance to Indian pathotypes of Puccinia graminis tritici and P. triticina in durum wheat

Stem rust and leaf rust are important diseases affecting durum wheat production in India. Inheritance and extent of diversity in resistance were studied in five durum genotypes, viz. ?B 662', ?ED 2398‐A', ?HG 110', ?IWP 5019' and ?Line 1172? using Pgt pathotypes 40A and 117‐6, and Pt pathotypes 12‐2 and 104‐2. F₂ and F₃ analyses showed that resistance was conferred by one or two genes in each line. In all, four genes for resistance to 40A, and eight each for pathotypes 117‐6 and 12‐2 were identified among the five genotypes, and three for resistance to 104‐2 among B 662, ED 2398‐A and IWP 5019 were indicated by tests of allelism. Although the gene identities are not known, at least some of them should be different from Sr2, Sr7b, Sr8a, Sr8b, Sr9e, Sr9g, Sr11, Sr12, Sr13, Sr14, Sr17, Sr23 and Sr28; and from Lr3, Lr14a, Lr23 and Lr27 + Lr31. These genotypes enrich the diversity of resistance to stem rust and leaf rust for durum wheat improvement.     

Alleviation of drought stress in maize (Zea mays L.) by using endogenous endophyte Bacillus subtilis in North West Himalayas

ABSTRACT

In the present study, we reported the isolation and molecular characterisation of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase-producing endophyte and its effect on alleviating drought stress in maize. Ten morphologically distinct indigenous plant growth-promoting rhizobacteria (PGPR) from maize roots and rhizosphere were screened for multiple plant growth-promoting (PGP) traits, and of ten, two strains (DHK and B1N1) possessing maximum PGP traits were evaluated at three water stress regimes in maize: (i) 80% field capacity (FC), (ii) 60% FC, and (iii) 40% FC for 45 days, starting 15 days after sowing to the maturity. Inoculation of DHK strain with maize at 80% FC induced a significant increase in plant biomass (root biomass, 86.67%; shoot biomass, 111.63%) together with decreased reactive oxygen species and increased activity of antioxidant enzymes (superoxide dismutase, 14.11?U/g fresh weight; peroxidase, 1.14?U/g fresh weight and catalase; 14.91?U/g fresh weight) compared to uninoculated control at same water regime (80% FC). The derivative strain also significantly accrued nutrients in maize and enhanced total chlorophyll and amino acid content in comparison with non-inoculated plants. 16S rDNA analysis of DHK strain revealed its lineage to Bacillus subtilis. Present investigations demonstrated the potential of the bacterial partner in alleviating drought stress in maize.     

Effect of complete feed block with tree leaves rich in hydrolysable and condensed tannins on nutrient utilization,rumen fermentation and growth performance of lambs

Thirty lambs (Avishaan genotype, 10 weeks old, 14.0 ± 0.2 kg live weight) were randomly assigned into three equal treatment groups to study the effect of complete feed blocks (CFB; concentrate and roughage at 70:30 ratio) with three different tanniniferous tree leaves on intake and utilization of nutrients, rumen fermentation, microbial protein synthesis and growth performance. The treatments were T1 (Control), CFB1 with Vigna sinensis hay; T2, CFB2 with Acacia nilotica leaves rich in hydrolysable tannins (HT); and T3, CFB3 with Ziziphus nummularia leaves rich in condensed tannins (CT). The three CFBs were fed ad libitum to the respective groups of lambs for a period of 12 weeks. There was lower (p < .05) intake of dry matter (DM), total carbohydrates (TCHO) and fibre components in T2 compared with T1 and T3. However, the digestibility of nutrients except crude protein (CP) was higher in T2. Diet had no effect (p > .05) on the LW gain in lambs. Amongst the three groups, T3 showed enhanced N utilization with a comparable microbial protein synthesis, the lowest being in T2. The T2 group of lambs had higher propionate and lower non-glucogenic: glucogenic short-chain fatty acids ratio. It may be concluded that tanniniferous tree leaves at 30% of total mixed ration can meet the requirement of nutrients for desired post-weaning growth.