Arbuscular mycorrhizal fungus and rhizobacteria affect the physiology and performance of Sulla coronaria plants subjected to salt stress by mitigation of ionic imbalance

Salt stress has become a major menace to plant growth and productivity. The main goal of this study was to investigate the effect of inoculation with the arbuscular mycorrhizal fungi (AMF; Rhizophagus intraradices) in combination or not with plant growth‐promoting rhizobacteria (PGPR; Pseudomonas sp. (Ps) and Bacillus subtilis) on the establishment and growth of Sulla coronaria plants under saline conditions. Pot experiments were conducted in a greenhouse and S. coronaria seedlings were stressed with NaCl (100 mM) for 4 weeks. Plant biomass, mineral nutrition of shoots and activities of rhizosphere soil enzymes were assessed. Salt stress significantly reduced plant growth while increasing sodium accumulation and electrolyte leakage from leaves. However, inoculation with AMF, whether alone or combined with the PGPR Pseudomonas sp. alleviated the salt‐induced reduction of dry weight. Inoculation with only AMF increased shoot nutrient concentrations resulting in higher K⁺: Na⁺, Ca²⁺: Na⁺, and Ca²⁺: Mg²⁺ ratios compared to the non‐inoculated plants under saline conditions. The co‐inoculation with AMF and Pseudomonas sp. under saline conditions lowered shoot sodium accumulation, electrolyte leakage and malondialdehyde (MDA) levels compared to non‐inoculated plants and plants inoculated only with AMF. The findings strongly suggest that inoculation with AMF alone or co‐inoculation with AMF and Pseudomonas sp. can alleviate salt stress of plants likely through mitigation of NaCl‐induced ionic imbalance, thereby improving the nutrient profile.     

污灌土壤中氟及硫的形态分布特征

以乌鲁木齐雅马里克山的石灰性土壤为研究对象,采用连续提取法和分步提取法对土壤氟和硫的化学形态进行了测定,研究了不同水质及外源对土壤氟和硫各形态的含量及其分布的影响.结果表明土壤氟主要以残渣态为主,占全氟含量99.5%以上.各形态氟呈残余态氟>有机束缚态氟>水溶态氟>可交换态氟>铁锰结合态氟的趋势.不同水质浇灌后,土壤硫主要以有机硫为主,占71.5%～81.2%.并且呈现有机硫>盐酸可溶性硫>水溶性硫>吸附性硫的趋势.外源物质对土壤理化性质及对土壤中氟和硫各形态有不同程度的影响.土壤氟和硫各形态之间以及各形态与土壤理化性质之间的相关性分析表明,全氟与残余态氟极显著相关.土壤全硫与有机硫之间具有十分密切的相关性.土壤pH值、有机质和CaCO₃含量是影响土壤中氟及硫赋存形态的主要土壤因子.     

Comparative study of the retrogradation of intermediate water content waxy maize, wheat, and potato starches

The retrogradation of extruded starches from three different botanical sources was studied in concentrated conditions (34 +/- 1% water) at 25 degrees C using differential scanning calorimetry (DSC) and isothermal calorimetry, Fourier transform infrared spectroscopy (FTIR), and wide-angle X-ray scattering. Potato starch showed the highest rate of retrogradation (approximately 0.17 h(-1)) followed by waxy maize (approximately 0.12 h(-1)), while the retrogradation of wheat starch was the slowest (approximately 0.05 h(-1)). In addition to the kinetics, the extent of molecular order in the retrograded samples was studied in detail in terms of "short-range" (helical) and "long-range" (crystalline) distance scales. The amylopectin crystallinity indices were essentially the same (approximately 47-51% amylopectin basis) for the three starches. However, significant differences were found in the enthalpy of melting measured by DSC after "full" retrogradation (potato, 11.6 +/- 0.7; waxy maize, 9.0 +/- 0.5; and wheat, 6.1 +/- 0.3 J/g of amylopectin). The degree of short-range molecular order in the retrograded state determined by FTIR was waxy maize > potato > wheat. The effect of amylopectin average chain length and the polymorphism of the crystalline phase were taken into account to explain the differences in the retrogradation enthalpies.     

Analytical characterization of Moringa oleifera seed oil grown in temperate regions of Pakistan

The hexane-extracted oil content of Moringa oleifera seeds ranged from 38.00 to 42.00%. Protein, fiber, and ash contents were found to be 26.50-32.00, 5.80-9.29, and, 5.60-7.50%, respectively. Results of physical and chemical parameters of the extracted oil were as follows: iodine value, 68.00-71.80; refractive index (40 degrees C), 1.4590-1.4625; density (24 degrees C), 0.9036-0.9080 mg/mL; saponification value, 180.60-190.50; unsaponifiable matter, 0.70-1.10%; and color (1 in. cell), 0.95-1.10 R + 20.00-35.30 Y. Tocopherols (alpha, gamma, and delta) in the oil were up to 123.50-161.30, 84.07-104.00, and 41.00-56.00 mg/kg, respectively. The oil was found to contain high levels of oleic acid (up to 78.59%) followed by palmitic, stearic, behenic, and arachidic acid up to levels of 7.00, 7.50, 5.99, and 4.21%, respectively. The induction period (Rancimat, 20 L/h, 120 degrees C) of the crude oil was 9.99 h and reduced to 8.63 h after degumming. Specific extinctions at 232 and 270 nm were 1.70 and 0.31, respectively. Many parameters of M. oleifera oil indigenous to Pakistan were comparable to those of typical Moringa seed oils reported in the literature. The results of the present analytical study were also compared with those of different vegetable oils.     

干旱区城市化对城市内河水质的影响研究——以吐曼河为例

随着城市社会经济的迅速发展，工业主导的城市化过程带来了许多城市生态环境问题，引起了城市内河水质的恶化。采用1996～2000年喀什市吐曼河水质观测数据、1990年与1999年卫星遥感图像和城市发展中有关的社会经济统计数据与土地利用资料，在3S技术的支持下，运用地表水污染综合指数法，对吐曼河水质进行评价，定量与定性相结合分析了干旱区城市化对城市内河水质的影响。结果表明：大气中的总悬浮颗粒是导致吐曼河水质严重污染的主要原因。此外，城市化所带来得人口增加、工业化与土地利用方式的改变也一定程度的影响了吐曼河的水质。     

达坂城地区荒漠及农业区鼠类群落的聚类分析

本文根据１９９３．８－１９９５．５的调查资料并采用了聚类分析对达坂城地区荒漠及农业区鼠类群落进行了分析研究,结果表明,该地区的鼠类可划分为３种群落,小林姬鼠＋褐家鼠＋小家鼠群落;小林姬鼠＋灰仓鼠群落;红尾沙鼠＋五趾跳鼠群落;群落的多样性指数以群落Ａ最高,次为群落;群落Ｃ的多样性最低。     

新疆山地针叶林乔木胸径-树高关系分析

树木的生长包括了径向生长和垂直生长两个方面,这两方面具有密切的关系,这一关系既受到树木本身的控制,同时也受森林立地条件的影响.通过分析新疆阿尔泰山、天山南北坡以及昆仑山区11个地点120个样方的胸径-树高关系.结果表明:昆仑山的尖削度(taper)显著大于其余3地,其潜在最大树高(potential height,H*...     

Influence of Heat Stress on the Cortisol and Oxidant‐Antioxidants Balance During Oestrous Phase in Buffalo‐Cows (Bubalus bubalis): Thermo‐protective Role of Antioxidant Treatment

In the present study, the effect of heat stress, which is commonly observed in the animals of Upper Egypt area in summer, as well as the effect of antioxidant treatment as a thermo‐protective was examined. In this study, the animals (n = 120) were divided into winter group (n = 40, bred during winter) and summer group (n = 80, bred during summer) as well as, animals in the summer group were divided into first subgroup animals (n = 40) and injected with Viteselen intramuscularly (15 ml) twice weekly for 10 weeks and second subgroup animals (n = 40) were not treated (as control). Serum levels of progesterone (P4), oestradiol (E2), cortisol, superoxide dismutase (SOD), lipid peroxidase (LPO) and nitric oxide (NO) were measured. The pregnancy rate of all animals was detected rectally. The levels of oestradiol and the activity of the antioxidant SOD were decreased in serum of animals in behavioural oestrus during summer as compared with those in winter. During the same time period the levels of oxidants such as LPO and NO were increased in the serum of animals again in the phase of oestrus. In another group of animals treated by intramuscular injection with 15 ml viteselen (antioxidant) twice weekly for 6 weeks during hot months, the activities of serum SOD showed an increase and the levels of oxidants and cortisol decreased. Moreover, the levels of oestradiol were increased during the oestrous behaviour. The pregnancy rate was decreased in animals under heat stress and the pregnancy rate was enhanced dramatically when these animals received antioxidants during the heat stress. This means that the heat‐stress in Upper Egypt may affect the fertility of animals and pregnancy rate and this effect may be through an increased production of free radicals and decreased production of antioxidants as well as increased levels of cortisol. Treatment of animals or supplementation with antioxidants before the beginning of months of heat‐stress and also during the stress period may correct the infertility due to heat‐stress through the decrease in cortisol secretion and a decrease in the oxidative stress. These results resulted in an increase in pregnancy rate in treated animals.