To identify resistance to Fusarium head blight (FHB), cereal yellow dwarf virus (CYDV), stem rust (Sr), and powdery mildew (Pm) in 24 common wheat (
A 27 years field experiment was conducted on a Fe-Accumli Stagnic Anthrosol to evaluate the effects of long-term application of fertilizer, pig manure (PM), and rice straw (RS) on rice yield, uptake, and usage efficiency of potassium, soil K pools, and the nonexchangeable K release under the double rice cropping system in South Central China. Common cropping pattern in the study was early rice-late rice-fallow (winter). The field treatments included CK (no fertilizer applied), NP, NK, NPK, and NK+ PM, NP+ RS, NPK+ RS. The pig manure and rice straw was applied in both the early rice and late rice cropping season. The ranking order of 27 years average annual grain yield were the CK<NK<NP<NK+ PM<NP+ RS<NPK<NPK+ RS treatments. The negative yield change trends were observed in the CK and NP and NK treatments of unbalanced nutrient application in the case of omitted-K and P-omitted. The positive yield change trends were observed in balanced applications of NPK and combined application of fertilizer (NPK) with pig manure (NK+ PM) or rice straw (NP+ RS and NPK+ RS). The application of K fertilizer (NPK) increased grain yield by 56.7 kg·hm-2·a-1 over that obtained with no K application (NP). The combined application of pig manure with fertilizer (NK+ PM) increased by 82.2 kg·hm-2 per year compared with fertilizer application alone (NK). The combined application of rice straw with fertilizer (NP+ RS and NPK+ RS) increased on the average of 34.4 kg·hm-2 per year compared with fertilizer application alone (NP and NPK). In all fertilizer, pig manure and rice straw combinations, K uptake change trends in rice plants of the early rice was positive except for CK and NP treatments. The results showed that the total removal of K by the rice plants exceeded the amounts of total K applied to the soil in all treatments, which showed a negative K balance. This ranged from 106.3 kg·hm-2·a-1 in CK treatment to 289.6 kg·hm-2·a-1 in the NPK+ RS treatment. Continuous annual application of 199.2 K kg·hm-2 to rice resulted in an accumulation (58 kg·hm-2) of exchangeable K (1 mol NH4OAc extractable K) in 0– 45 cm soil depth over the study period, despite the higher average annual uptake of K by the system (225.7 kg·hm-2). However, nonexchangeable K increased substantially from 1090 kg·hm-2 to 1113 kg·hm-2 and 1140 kg·hm-2 in the 0–45 cm soil layer in NPK+ RS and NPK treatments after 27 years of the continuous double rice cropping system, respectively. Thus, long-term rational application of K fertilizer may increase sustainable K fertility of the continuous double rice cropped system.
An efficient protein extraction method for two-dimensional gel electrophoresis (2-DE) from plant samples is usually challenging due to the low protein content and high level of interfering compounds. Proteomic analyses of rice (
To understand the role of microbial processes in phosphorus (P) immobilization in a weathered subtropical soil, the effects of application of a phosphate-solubilization microorganism strain (
A system to improve isolated microspore embryoid induction rate of pepper (
The presence of indigenous endophytic bacteria in tissue-cultured seedlings germinated from seeds of
An efficient and stable cDNA-amplified fragment length polymorphism (cDNA-AFLP) analysis system for Chinese jujube was established and successfully used for the studies of related stoneless gene difference expression in
The chalcone synthase gene (
Through treating fruits at higher temperatures, choosing natural fruits on different exposures on a tree canopy and collecting exclusively both sunburn and normal fruits, the metabolic patterns were studied by comparing the activity of key enzymes in the ascorbate-glutathione (AsA-GSH) cycle including ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAR), and glutathione reductase (GR). The results indicated that the activity of three enzymes increased under around less than 35°C acclimating conditions, with no significant changes in membrane electrolyte leakage. The activity of APX, MDAR, and GR rose during the initial stage when fruits were treated at 45°C but decreased significantly as treating time extended. A time response existed in APX, MDAR, and GR to high temperature. For example, APX activity reached the maximum when fruits were treated for 1 h, however, MDAR and GR showed the peak when fruits were treated for 3 h and 5 h, respectively, implying the possible acting sequence relationship of three enzymes in the AsA-GSH cycle. In view of the whole cycle, APX served as the first enzyme directly scavenging active oxygen species, followed by a series of chain reactions to regenerate ascorbic acid (AsA), and GR served as the last post in the cycle. Because various ecological conditions existed in a tree canopy, there was a significant difference in the enzymatic activity among fruits bearing on either exterior or interior canopy. A significantly higher activity of APX and MDAR was found with exterior fruits, compared with interior ones, which may be regarded as a frequent acclimation to high temperature and excessive sunlight.
The effects of drought during preplanting (three treatments: soil relative water content (RWC) 75%–80%, 55%–60%, 35%–40%; B1, 2, and 3, respectively) and postplanting (four treatments: RWC 75%–80%, 55%–60%, 35%–40%, 15%–20%; A1, 2, 3, and 4, respectively) on electrical impedance spectroscopy (EIS) parameters in the stems of
The allelopathic influence of aqueous extracts of
An efficient extraction method by ultrasound-assisted extraction (UAE) was developed for the extraction of polychlorinated biphenyls (PCB 28, 52, 101, 118, 130, 153, 180) from various shellfish. Analytes were determined by gas chromatography–mass spectrometry in selected ion monitoring (SIM) mode. All the samples were extracted by n-hexane and decontaminated by concentrated sulfuric acid. The resulting samples were determined by quantitative detection by comparing with external standards. The average recoveries of seven kinds of PCBs ranged from 80.92% to 93.89%, and the lowest detectable limit was 0.08–0.03 μg·kg-1. The average concentrations of total PCBs were 14.12–30.61 μg·kg-1 in the samples. This method was highly effective in reducing the cost and time for the pretreatment of samples. This method may be applied for the screening and monitoring of shellfish for organic pollutants in coastal waters.
The present study was conducted to evaluate the effects of different folic acid supplemental levels on growth performance, serum biochemical indicators, and hepatic folate metabolism-related gene expressions in weaned piglets. There were 160 piglets with initially average bodyweight of 7.33 kg randomly assigned to diets containing five levels of folic acid: basal diets (C), 0.5 mg·kg-1 folic acid (FS 0.5), 2.5 mg·kg-1 folic acid (FS 2.5), 5.0 mg·kg-1 folic acid (FS 5.0), or 10.0 mg·kg-1 folic acid (FS 10.0). Blood samples were collected from a subset (
The goal of this study is to enumerate
Six purified vitamin-free casein-based diets were formulated to contain six levels vitamin A at 0, 500, 1000, 2000, 4000, and 8000 IU·kg-1, respectively. Tilapias (initial mean weight: 7.73±0.03 g) were fed the diets in quadruplicate aquaria to apparent satiation twice daily for 10 weeks. No differences in mortality, weight gain, or feed efficiency ratio (FER) were observed among the groups. Liver vitamin A levels reflected dietary vitamin A levels. Immune parameters, such as hemoglobin levels, total cell count, red blood cell count, total serum protein, and serum lysozyme activity, did not vary with the dietary vitamin A levels. White blood cell counts of fish in 2000 IU·kg-1 diet groups were significantly higher than that in other diets groups. Serum complement activities of fish in 2000 and 4000 IU·kg-1 vitamin A diet groups were also higher than those in other diet groups. After the 14-d challenge test, the mortality and antibody titer were similar among the treatments. The results indicated that dietary vitamin A inclusions did not affect the immune response of