Leptochloa fusca (sprangletop).

Leptochloa fusca is a perennial weed with a global distribution. It is an aggressive species showing a competitive advantage in many situations due to its tolerance of saline and alkaline soils and its likely ability to fix nitrogen. It is commonly a serious weed of rice in many countries. It is recorded as invasive in Cuba, Hawaii and in the Chagos Archipelago (as L. fusca subsp. uninervia) and has been the subject of an 'eradication action' in Europe.

Comparative study of fodder halophytes in saline and alkaline soils

A research was conducted in 2014-15 to know the usefulness of halophytes on saline and sodic stress with 3 halophytes and 6 treatments i.e Control (pH-7.0 and ECe-0.56), Sodic (pH-9.5 and 10.0) and Saline (ECe- 15, 25 and 35 dSm-1) which was done in Factorial randomized block design in small micro-plots in research area at Central Soil Salinity Research Institute, Karnal, Haryana. We found that pHs of soils were less and ECe of soils were more affected by growing halophytes in this experiment. Dicanthium had more number of tillers and Suaeda had more number of branches under sodic stress. In case of Urochondra Setulosa, number of tillers had increased up to pH-9.5 thereafter it decreased. Likewise, all other plant nutrients concentration in the soil was found to be reduced which showed that halophytes utilized these nutrients for their growth under the stress conditions. the results showed that Dicanthuim annulatum can be grown as a fodder crop under low to high sodic stress conditions whereas Suaeda nudiflora and Urochondra setulosa can be grown easily under saline soils/ irrigated condtions and in areas with sea water.

Effects of rooting powder and soil salt stress on the growth and physiological characteristics of Tamarix chinensis cuttings

Background: Vegetation restoration is a main ecological remediation technology for greening saline and alkaline soils. The objectives of this study were to determine whether aminobenzotriazole (ABT), a rooting powder, can be used to improve the physiological regulatory abilities of Tamarix chinensis under salt stress; to reveal the physiological regulatory pattern by which T. chinensis pre-treated with ABT adapts to salt stress. Results: (1) As the salt stress level increased, the cutting survival rate, height, and root length of T. chinensis gradually decreased, whereas their biomass first decreased and then increased. At salt content（ S c）>0.9%, cutting propagation of T. chinensis was difficult, and there was a considerable decrease in its biomass. The effectiveness of ABT in improving the survival rate and growth of T. chinensis cuttings became increasingly pronounced as the salt stress level increased. (2) T. chinensis was found to adapt to salt stress through increased Chl content. However, excess salt stress inhibited Chl synthesis. ABT can be used to widen the range of tolerance of T. chinensis seedlings to salt stress during Chl synthesis. (3) T. chinensis can eliminate excess reactive oxide species (ROS) by enhancing SOD and POD activities. An excess accumulation of ROS will impede the increase in enzyme activities. ABT can help improve T. chinensis seedling enzyme system regulation and was found to be most effective at a concentration of 100 mg·L -1 . (4) ABT can reduce MDA accumulation and damage caused by membrane lipid peroxidation (MLP). ABT at a concentration of 100 mg·L -1 was found to be highly effective in reducing MDA content. Conclusions: ABT was effective in improving the survival rate and the growth and physiological regulatory abilities of T. chinensis cuttings under salt stress. ABT enhanced the resistance of T. chinensis to salt stress. However, under high S c (>0.9%) and ABT concentration (>100 mg·L -1 ) conditions, the physiological regulatory ability of T. chinensis seedlings exposed to salt stress weakened. At S c of 0.9%, T. chinensis seedlings pre-treated with ABT at 100 mg·L -1 exhibited the most vigorous growth, highest biomass, and highest physiological and biochemical regulatory abilities.

Kocuria dechangensis sp. nov., an actinobacterium isolated from saline and alkaline soils

A Gram-stain positive, strictly aerobic, non-motile and coccus-shaped actinobacterium, designated strain NEAU-ST5-33T, was isolated from saline and alkaline soils in Dechang Township, Zhaodong City, PR China. It formed beige-yellow colonies and grew at NaCl concentrations of 0–5 % (w/v) (optimum 0 %), at pH 6.0–9.0 (optimum pH 7.0) and over a temperature range of 4–50 °C (optimum 35 °C). Based on 16S rRNA gene sequence analysis, strain NEAU-ST5-33T was phylogenetically closely related to the type strains of species of the genus Kocuria, Kocuria polaris CMS 76orT, Kocuria rosea DSM 20447T, Kocuria turfanensis HO-9042T, Kocuria aegyptia YIM 70003T, Kocuria himachalensis K07-05T and Kocuria flava HO-9041T, with respective sequence similarities of 98.8 %, 98.8 %, 98.3 %, 98.1 %, 98.1 % and 97.9 %. DNA–DNA hybridization relatedness values of strain NEAU-ST5-33T with type strains of the closely related species ranged from 54 ± 1 % to 34 ± 1 %. The DNA G+C content was 61.2 mol%. The major fatty acids (>5 %) were C15 : 0 anteiso, C15 : 0 iso and C16 : 1ω7c and/or C16 : 1ω6c. The major menaquinone detected was MK-8 (H2), and the polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unknown aminolipid and one unknown lipid. On the basis of the genotypic, chemotaxonomic and phenotypic data, we propose that strain NEAU-ST5-33T represents a novel species of the genus Kocuria, with the name Kocuria dechangensis sp. nov. The type strain is NEAU-ST5-33T ( = CGMCC 1.12187T = DSM 25872T).

Pseudomonas zhaodongensis sp. nov., isolated from saline and alkaline soils

Strain NEAU-ST5-21T was isolated from saline and alkaline soils in Zhaodong City, Heilongjiang Province, China. It was aerobic, Gram-stain-negative, rod-shaped and motile with a polar flagellum. It produced yellow–orange colonies with a smooth surface, and grew in the presence of 0–5 % (w/v) NaCl (optimum 0 %, w/v), at temperatures of 20–40 °C (optimum 28 °C) and at pH 7–11 (optimum pH 7). Phylogenetic analyses based on the separate 16S rRNA gene sequences and concatenated 16S rRNA, gyrB and rpoD gene sequences indicated that strain NEAU-ST5-21T belongs to the genus Pseudomonas in the class Gammaproteobacteria . The most closely related species is Pseudomonas xanthomarina , whose type strain (KMM 1447T) showed gene sequence similarities of 99.0 % for 16S rRNA, 81.8 % for gyrB and 85.0 % for rpoD with strain NEAU-ST5-21T. DNA–DNA hybridization values between strain NEAU-ST5-21T and P. xanthomarina DSM 18231T, Pseudomonas kunmingensis CGMCC 1.12273T, Pseudomonas stutzeri DSM 5190T, Pseudomonas oleovorans subsp. lubricantis DSM 21016T, Pseudomomas chengduensis CGMCC 2318T, Pseudomonas alcaliphila DSM 17744T and Pseudomonas toyotomiensis DSM 26169T were 52±0 % to 25±2 %. The DNA G+C content of strain NEAU-ST5-21T was 65 mol%. The major fatty acids (>10 %) were C18 : 1ω7c and/or C18 : 1ω6c, C16 : 1ω7c and/or C16 : 1ω6c and C16 : 0, the predominant respiratory quinone was ubiquinone 9, and polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, one unknown phospholipid, phosphatidylglycerol, one unknown aminolipid, one unknown lipid and a glycolipid. The proposed name is Pseudomonas zhaodongensis sp. nov., NEAU-ST5-21T ( = ACCC 06362T = DSM 27559T) being the type strain.