Application of chemical fertilizers and farmyard manure affects crop productivity and improves nutrient cycling within soil-plant systems, but the magnitude varies with soil-climatic conditions. A long-term (1982-2004) field experiment was conducted to investigate the effects of nitrogen (N), phosphorus (P), and potassium (K) fertilizers and farmyard swine manure (M) on seed and straw yield, protein concentration, and N uptake in the seed and straw of 19-year winter wheat (Triticum aestivum L.) and four-year oilseed (three-year canola, Brassica napus L. in 1987, 2000 and 2003; one-year flax, Linum usitatisimum L. in 1991), accumulation of nitrate-N (NO3-N) in the soil profile (0-210cm), and N balance sheet on balanced application of N, P, and K fertilizers and manure at proper rates is important for protecting soil and groundwater from potential NO3-N pollution and for maintaining high crop productivity in the rainfed region of Northwestern China.

Interrelationship among abscisic acid (ABA) content, accumulation of free polyamines and biosynthesis of β-N-oxalyl-L-α,β-diaminopropionic acid (ODAP) was studied in grass pea (Lathyrus sativus L.) seedlings under drought stress induced by 10% polyethylene glycol (PEG6000). Increase of ABA content occurred prior to that of ODAP and polyamine contents, and was found significantly positive correlation between ABA content and ODAP content. Addition of exogenous ABA increased ODAP content in leaves. On the other hand, pretreatment with α-difluoromethylarginine (DFMA), a polyamine biosynthesis inhibitor, significantly suppressed the accumulation of free putrescine (Put), free spermidine (Spd) and free spermine (Spm), which in turn inhibited biosynthesis of ODAP in well-watered leaves. Meanwhile, addition of exogenous Put alleviated DFMA-induced inhibition on the biosynthesis of Put and Spd, but did not affect the biosynthesis of Spm and ODAP in well-watered leaves. Same result was also achieved in drought-stressed leaves. Increasing accumulation of ODAP was significantly correlated with increasing Spm content (R=0.7957**) but not with that of Spd and Put. Therefore, it can be argued that ABA stimulated the biosynthesis of ODAP simultaneously with increasing the level of free Spm under drought stress condition.

We determined a minimum effective dose of gallic acid (3,4,5-trihydroxy benzoic acid; 50mg/kg, i.p.) and piperine (10mg/kg, p.o.) through their therapeutic potential and further evaluated them individually and in combination against beryllium-induced biochemical alterations and oxidative stress consequences in female albino rats. The administration of beryllium altered blood biochemical variables by significantly depleting hemoglobin, albumin and urea, whereas it enhanced bilirubin and creatinine. The release of serum transaminase, lactate dehydrogenase and/-glutamyl transpeptidase was significantly greater, and was concomitant with a decrease in serum alkaline phosphatase. A significant increase in lipid peroxidation and a decrease in glutathione, superoxide dismutase and catalase in the liver and kidney was an indication of oxidative stress due to beryllium exposure. Individual administration of gallic acid and piperine moderately reversed the altered biochemical variables, whereas the combination of these was found to completely reverse the beryllium-induced biochemical alterations and oxidative stress consequences. We concluded that gallic acid exerts a synergistic effect when administered with piperine and provides a more pronounced therapeutic potential in reducing beryllium-induced hepatorenal dysfunction and oxidative stress consequences.

The aim of this study was to investigate the spatial distribution patterns of soil seed bank of Stipagrostis pennata (Trin.) de Winter during different seasons in the Gurbantonggut Desert of north-west China.Results indicated that spatial patterns of the soil seed bank of S. pennata were similar to the distribution patterns of its associated standing vegetation, and there was a significant variation in soil seed densities among the different parts of the dunes.The highest soil seed density was found on the top of sampled dunes and in the soil of the underlayers of standing vegetation beds of S. pennata.The number of seeds stored in the soil decreased with distance from established stands of this grass species.Moreover, during secondary seed dispersal, which is air-borne in the windy season, a small proportion of seeds was also trapped by other plant species.Furthermore, the directional density distribution of seeds was strongly associated with the directions of the prevailing threshold wind (X6ms 1), and higher soil seed densities usually occurred on the leeward side of the vegetation stands.Based on these investigations, wind is, probably, the key factor in forming the spatial patterns of S. pennata seed banks in the region.On the other hand, grazing affected the quality and quantity of S. pennata seed storage, as a result of delayed development and the above-ground shoots being damaged by grazing.This occurred in spring to early summer, which is the most suitable growth season for the grass.Nevertheless, grazing had little influence on the spatial distribution patterns of the seed bank over all seasons.Germination trials showed that the percentage of viable soil seeds increased continuously throughout summer and autumn.The results also revealed the clear ecological characteristics influencing the population distribution of S. pennata.