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[en] Chinese wheat cultivar Lantian 9 showed a stable high yield in the field. Together with its other desirable traits such as tolerance to cold, drought, leaf rust and stripe rust, made it a good source for wheat breading. In our preliminary test, Lantian 9 showed a typical adult resistance phenotype (susceptible at seedling stage but high resistance at adult stage) to most of the major Chinese leaf rust pathotypes. To clarify the adult-plant resistance (APR) genes in this cultivar, a population with 197 F2:3 lines was generated by crossing Lantian 9 with susceptible line Huixian Hong. The population was phenotyped in the field over three years (year 2012, 2013 and 2014) by a mixture of three leaf rust pathotypes (THTT, THTS and THTQ). A total of 1232 simple sequence repeat (SSR) markers were used to screen the parental lines. Polymorphic ones were further applied on the population. Linkage mapping analysis showed that one QTL from Lantian 9 was located on chromosome 2BS, which was relative stable among the data from the year 2012 and 2013 with phenotypic variations of 6.0% and 9.1%, respectively. Three other QTLs from Lantian 9 on chromosome 4BS, 3A and 1BL were detected. We also identified one QTL from Huixian Hong on chromosome 1BL. All these identified wheat leaf rust resistance QTLs with their closely linked molecular markers will greatly facilitate genetic improvement of wheat resistance to leaf rust in China. (author)

[en] In a laboratory trial three chickpea varieties viz, Karak-I, Karak-III and Shenghar were tested against the phytotoxicity of five weed species: Parthenium hysterophorus L., Phragmites australis (Cav.) Trin., Datura alba L., Cyperus rotundus L. and Convolvulus arvensis L.in January 2013. The weed extracts were prepared at the rate of 120 g/L (w/v) after shade dry. The results indicated highly significant inhibitory effect of all the tested weed species on the chickpea varieties. The results also showed that the chickpea variety Karak-III was more susceptible to the phototoxicity of the tested weed extracts. Among the extract, C. arvensis proved much toxic in term of inhibition of germination by giving only 43.33% germination in comparison with control where 97.50% germination was recorded. On the other hand, the effect of P. australis extract was found a little stimulator by speeding the seed germination in all varieties and giving a low (2.21) mean germination time (MGT) value. From the current results it can be concluded that the infestation of C. arvensis can pollute the soil by accumulating toxic chemicals that leads to the germination failure and growth suppression in chickpea. Therefore, the prevention and removal of C. arvensis in the chickpea growing areas could be recommended. In addition, P. australis must be tested against chickpea weeds (chickpea varieties withstand against its phototoxicity), so that it can be popularized as bio herbicide in chickpea if it gave promising results in controlling chickpea weeds. (author)

[en] For experimental purposes it is recommended that one use cooled sprouts in a stage of delayed growth. Cooled sprouts have a high sensitivity to environmental effects and can be used in long-term (up to one or two months) experiments. The authors discuss the influence of suboptimum temperatures on the radiosensitivity of seedlings, the development of radiation damage and persistence of the radiobiological effect

[en] Moringa oleifera Iam is a very important species because of it's multiple uses. The tree grows in many parts of the world including Asia, Africa, Central America and South America. In Kenya, it grows in drier regions of Baringo, Kibwezi, Mandera and the coastal strip. These regions are known to have substantially high level of soluble salts. The study aims at finding the effect of salinity on germination and early seedling growth of M. oleifera seedlings. This was tested in Moi University department of forestry laboratory by varying the concentration of Nacl moles (0.01, 0.03, 0.05, 0.07 and 0.09) in germination medium. The petri dishes with germination media were placed in the incubator at 30 degrees Celsius each containing 25 seeds of each treatment replicated four times. The effect of seedling growth and development was tested in the greenhouse. This was done by varying the concentration of Nacl moles (0.05, 0.15, 0.25, 0.35 and 0.45) in the forest soil used in the experiment. After germination one seedling per treatment was randomly selected and then carefully dug. The root length, shoot height, total dry matter, stem dry matter and leaves dry matter were measured. This was repeated at intervals of one week for seven weeks. The data obtained from the experiments were analysed using ANOVA based on generalized linear modelling procedures. The tests indicated that M. oleifera seed germination and early seedling growth was significantly (p<0.05) affected by salinity. The seedlings also demonstrated development of swellings in the root region and the development of multiple stems for salt concentrations of 0.05 moles and above. These observations show that M. oleifera is affected by salinity in both seed germination and early seedling growth

[en] The present paper contains the data of photosynthetic activity and stomatic aperture of bean-seedlings Ieaves, and the relations obtained with both results. It has been observed that the product of photosynthetic activity by the resistance; to transpiration measured by a promoter ia a constant, between some limits. (Author) 45 refs

[en] Fire suppression and other anthropogenic activities have the potential to eliminate ecological barriers that previously kept related, sympatric species from interbreeding. We compared artificial F1 shortleaf pine (Pinus echinata Mill.) x loblolly pine (Pinus taeda L.) hybrids with their parents to determine potential traits that have allowed hybrid seedlings to dramatically increase in abundance since 1950s. Six open-pollinated families each of loblolly and shortleaf pine as well as 12 controlled crosses were compared over 2 years in Oklahoma, USA. Loblolly and hybrid seedlings had higher establishment and growth rates than shortleaf pine. The hybrid seedlings had similar numbers of sprouts following top-clipping as shortleaf, which were higher than those of loblolly pine. Formation of a strong basal crook, an adaptation to protect dormant buds from fire, was greatest in shortleaf and lower in hybrid and loblolly pine. Instantaneous water use efficiency indicated that hybrid pine had similar high water use efficiency as shortleaf pine compared with loblolly pine. In the absence of fire, the hybrid seedlings perform at least as well as the parent species, which points out the importance of fire to eliminate hybrids and maintain the genetic integrity of shortleaf pine native to fire-prone, xeric sites. (author)

[en] Accumulation of ³²p in the insect body of rice stem borer (chilo suppressalis walker) and labelling efficiency. Labelling of C. suppressalis months with ³²p though larval feeding with rice seedling indicated good result. Labelling efficiency at a given dose of 50 μVi/50 ml reached 81% at 100 μCi/50 ml was 95%. Forty percent of the total labelled individuals contained radioactivity greater than 1500 counts per minute as measured by liquid scintillation counter with 57.5% efficiency. Accumulation of ³²p in the labelled insects was found mostly (50%) in the abdomen. The remaining 50% were distributed to the thorax (34%), to the head (9%) and to the wings (7%). (author). 6 refs

[en] Bioassays were conducted to test the phytotoxic potential of Celtis australis against Trifolium alexandrinum, Brassica campestris, Triticum aestivum and Lactuca sativa under laboratory condition. Aqueous extracts from twigs and leaves were obtained by soaking 5 and 10g plant material in 100 ml distilled water for 24 and 48hr durations. Aqueous extracts significantly delayed/retarded the germination and reduced the plumule and radicle growth of all the four test species. Generally, extracts soaked for 48h especially 10 gm/100ml were inhibitory than 24h extracts of 5 or 10gm material. Extracts from twigs were inhibitory to germination of wheat while same extracts inhibited the plumule growth of B. campestris. Radicle growth of T. alexandrinum was inhibited more by twig extracts. Hot water extracts from twigs were less inhibitory than leaf extracts. Litter and mulch also significantly delayed the seed germination and retarded the overall growth of seedlings of all test species. The number and length of seminal roots of T. aestivum was suppressed by all aqueous extracts, added litter and mulch. The inhibitory response depended upon the test species, concentration, soaking duration and physiological parameters. The results suggested that Celtis australis has strong phytotoxic potential. (author)

[en] The study was conducted to evaluate the effect of NaCl salinity on germination and emergence of Physalis ixocarpa and Physalis peruviana. Seeds of P. ixocarpa and P. peruviana were germinated by the use of 0, 30, 60, 90, 120 and 180 mM NaCl solutions in petri dishes. Final germination percentage (FGP) decreased with the increase in NaCl concentration. Both species germinated at the ranges of salinity. P. peruviana gave the greater germination percentages under salt stress than P. ixocarpa. NaCl salinity at different concentrations adversely affected germination rates. For seedling growth, seeds of both species were sown at 10 mm depth in plastic trays filled with peat to determine final emergence percentage (FEP). The trays were irrigated manually to saturation every day with 0, 30, 60, 90, 120, 150 or 180 mM NaCl solutions to maintain the level of salinity. Salinity affected seed emergence and seedlings growth more than seed germination. The study showed that no emergence of Physalis was observed at 90, 120 and 180 mM NaCl salinity. Fresh and dry weights of normal seedlings were also evaluated. Salt stress significantly decreased the plant fresh and dry weight of both species. Based on the results of the experiment, it can be concluded that seedling emergence and growth is more sensitive to salt stress than seed germination in Physalis. (author)