Detection, seedborne nature, disease transmission and eradication of seedborne infection by rhizoctonia bataticola (Taub) butler in groundnut

A study was conducted to determine the seedborne nature, disease transmission and eradication of seedborne infection by Rhizoctonia bataticola in groundnut. In case of 10 groundnut accessions, infection percentage of R. bataticola, ranged between 13.3 to 73.3. Component-plating method indicated that the pathogen is located mainly on the seed coat and rarely in the endosperm and embryo. Infection in embryo and endosperm was always associated with seed coal infection. All accessions showed pre-emergence damping-off in the form of seed rot. Post- emergence damping-off was noticed in three accessions. The per cent infection ranged between 9.5 to 42.9 in case of pre-emergence damping-off. while it was 4.8 to 19.1 for post-emergence damping-off. The latent infection of R. bataticola from healthy seedlings was proved using Potato carrot agar medium. Infected seeds of 10 groundnut accessions were gi~own and no apparent symptoms were observed on the plants for one season, but seeds harvested from such plants resulted in seed infection of 6.1 - 33.3 % indicating the seed transmission nature of the pathogen from one generation to the next. Carbendazim + tin ram @ 2g a.i / kg seed can be used as a routine treatment in quarantine laboratories to eliminate R. bataticola from groundnut seed

Movement and activity pattern of a collared tigress in a human-dominated landscape in central India

Tigers (Panthera tigris) are wide-ranging species, and a permeable landscape matrix outside Protected Areas (PAs) is extremely important for their dispersal. A tigress which had fallen in a water duct in the Nagpur district was rescued by the Forest Department on 12th October, 2011 and released on 27th November, 2011 in a forest adjacent to the site of capture. A GPS-GSM collar that we fitted on her indicated that she remained in the same forest area until 25th December, 2011, and then moved eastwards into a human-dominated landscape where she was present until 25th March, 2012, after which the GPS battery ceased to function. She moved a minimum distance of 454.65 km from the time of her release up to 25th March, 2012, using a total area of 726 km² (95% MCP), but between 30th December, 2011 and 25th March, 2012, after moving into the human-dominated forest-agricultural landscape her home range was 431 km² (95% MCP). Her home range also encompassed villages, roads and croplands. Her activity was largely nocturnal and she rested in dense foliage inside forest patches during the day. About half of all the prey items that we identified during this period (n = 12) were wild pigs (Sus scrofa). Although, she was present very close to areas where humans were active in the day, no untoward incident occurred. She was photographed in April 2013, a year after the collar stopped functioning, in the same region about 40 km from the release site, indicating that she is still present in the human-dominated area. Very little is known about tiger ecology, and their temporal and spatial patterns of movement, outside PAs. These areas will be crucial in terms of dispersal between PAs as well as sensitive in terms of conflict

Differential cross sections and recoil polarizations for the reaction gamma p -> K+ Sigma0

High-statistics measurements of differential cross sections and recoil polarizations for the reaction $\gamma p \rightarrow K^+ \Sigma^0$ have been obtained using the CLAS detector at Jefferson Lab. We cover center-of-mass energies ($\sqrt{s}$) from 1.69 to 2.84 GeV, with an extensive coverage in the $K^+$ production angle. Independent measurements were made using the $K^{+}p\pi^{-}$($\gamma$) and $K^{+}p$($\pi^-, \gamma$) final-state topologies, and were found to exhibit good agreement. Our differential cross sections show good agreement with earlier CLAS, SAPHIR and LEPS results, while offering better statistical precision and a 300-MeV increase in $\sqrt{s}$ coverage. Above $\sqrt{s} \approx 2.5$ GeV, $t$- and $u$-channel Regge scaling behavior can be seen at forward- and backward-angles, respectively. Our recoil polarization ($P_\Sigma$) measurements represent a substantial increase in kinematic coverage and enhanced precision over previous world data. At forward angles we find that $P_\Sigma$ is of the same magnitude but opposite sign as $P_\Lambda$, in agreement with the static SU(6) quark model prediction of $P_\Sigma \approx -P_\Lambda$. This expectation is violated in some mid- and backward-angle kinematic regimes, where $P_\Sigma$ and $P_\Lambda$ are of similar magnitudes but also have the same signs. In conjunction with several other meson photoproduction results recently published by CLAS, the present data will help constrain the partial wave analyses being performed to search for missing baryon resonances.Comment: 23 pages, 17 figure

Near-threshold Photoproduction of Phi Mesons from Deuterium

We report the first measurement of the differential cross section on $\phi$-meson photoproduction from deuterium near the production threshold for a proton using the CLAS detector and a tagged-photon beam in Hall B at Jefferson Lab. The measurement was carried out by a triple coincidence detection of a proton, $K^+$ and $K^-$ near the theoretical production threshold of 1.57 GeV. The extracted differential cross sections $\frac{d\sigma}{dt}$ for the initial photon energy from 1.65-1.75 GeV are consistent with predictions based on a quasifree mechanism. This experiment establishes a baseline for a future experimental search for an exotic $\phi$-N bound state from heavier nuclear targets utilizing subthreshold/near-threshold production of $\phi$ mesons

A comparison of forward and backward pp pair knockout in 3He(e,e'pp)n

Measuring nucleon-nucleon Short Range Correlations (SRC) has been a goal of the nuclear physics community for many years. They are an important part of the nuclear wavefunction, accounting for almost all of the high-momentum strength. They are closely related to the EMC effect. While their overall probability has been measured, measuring their momentum distributions is more difficult. In order to determine the best configuration for studying SRC momentum distributions, we measured the $^3$He$(e,e'pp)n$ reaction, looking at events with high momentum protons ($p_p > 0.35$ GeV/c) and a low momentum neutron ($p_n< 0.2$ GeV/c). We examined two angular configurations: either both protons emitted forward or one proton emitted forward and one backward (with respect to the momentum transfer, $\vec q$). The measured relative momentum distribution of the events with one forward and one backward proton was much closer to the calculated initial-state $pp$ relative momentum distribution, indicating that this is the preferred configuration for measuring SRC.Comment: 8 pages, 9 figures, submitted to Phys Rev C. Version 2 incorporates minor corrections in response to referee comment

Comment on the narrow structure reported by Amaryan et al

The CLAS Collaboration provides a comment on the physics interpretation of the results presented in a paper published by M. Amaryan et al. regarding the possible observation of a narrow structure in the mass spectrum of a photoproduction experiment.Comment: to be published in Physical Review

Absorption of the ω\omega and ϕ\phi Mesons in Nuclei

Due to their long lifetimes, the $\omega$ and $\phi$ mesons are the ideal candidates for the study of possible modifications of the in-medium meson-nucleon interaction through their absorption inside the nucleus. During the E01-112 experiment at the Thomas Jefferson National Accelerator Facility, the mesons were photoproduced from $^{2}$H, C, Ti, Fe, and Pb targets. This paper reports the first measurement of the ratio of nuclear transparencies for the $e^{+}e^{-}$ channel. The ratios indicate larger in-medium widths compared with what have been reported in other reaction channels.Comment: 6 pages, 4 figure