Fusarium oxysporum is one serious soil-borne pathogenic fungus and is listed as one of the top ten plant fungal pathogens in the world. This fungus can infect more than 100 economically important crops such as cotton,soybean,watermelon,banana,tomato and alfalfa,causing wilt and root rot. The detection and quantification of F. oxysporum in soil and plant root tissues is the basis for early diagnosis and effective control of the disease. This article summarizes the research progress and application of F. oxysporum detection and quantification methods at domestic and overseas,mainly including medium colony plate dilution method,conventional PCR and real-time fluorescent quantitative PCR,etc. This review provides theoretical guidance for F. oxysporum detection and quantification in agriculture.

Glutathione (GSH), an important antioxidant in plants, can scavenge the redundant active oxygen free radicals produced during cell metabolism processes and relieve the damage caused by membrane lipid peroxidation. GSH contributes to the role of adversity stress resistance in plants. This review summarizes GSH activities including the types of GSH in plants, the application of GSH and the physiological mechanism of GSH protecting plant cells including scavenging intracellular active oxygen free radicals, forming non-toxic compound by combining with toxic heavy metal material, absorbing and transporting amino acid, resisting to adversity stress (temperature stress, drought stress, heavy metal stress and salt stress). GSH metabolism plays a positive role for understanding the physiological function of plant antioxidants, knowing the mechanism of scavenging active oxygen free radicals, and studying plant resistance.

To understand the dynamic variation of the detergent fibre of tropical leguminous forages and their responses to the fertilization during the growing period,a multifactor random pot-experiment was set up.The five tested tropical leguminous forage species were Stylosanthes guianensis(Aubl.) Sw.cv.CIAT184(S1), Chamaecrista rotundifolia(Pers.) Greene cv.CPI34721(S2), C.rotundifolia cv.CPI86134(S3), C.rotundifolia cv.ATF3248(S4),and C.nictitans(L.) Moench cv.ATF2217(S5),three fertilization levels were no fertilization(F0),ordinary fertilization level(F1;N,P,K were 25,40,50 kg·hm ^-2,respectively),and diploid fertilization level(F2;N,P,K were 50,80,100 kg·hm ^-2,respectively),and four harvests employed on Jul.25(C1),Aug.29(C2),Oct.8(C3) and Nov.14(C4),respectively.The results show that S4 and S1 had the highest level(53.4% and 52.7%) of NDF(neutral detergent fibre),S5 and S3 the lowest level(47.9% and 46.9%);the difference between the two groups was very significant( P<0.01),but they had no significant differences from S2,respectively.The content of ADF(acid detergent fibre) and ADL(acid detergent lignin) in S5(23.0% and 9.1%) were significantly lower than those of other 4 species(28.0%~29.0% and 11.1%~12.3%)( P<0.01).In comparison with F1 treatment,F2 significantly decreased the ADF content( P<0.01) but less effect on the content of NDF and ADL.Fertilization significantly decreased the content of deterged fiber during the C3 stage( P<0.05);the content of NDF,ADF,and ADL under F1 and F2 treatments decreased by 6.6%,5.4%,9.7%,6.9%,2.6%,1.6% in comparison with F0,respectively;the content of ADF and ADL in F2 were significantly lower than those in F1( P<0.05).The deterged fiber content was increased continuously along with the harvest progress,especially the average ADF values of five forage species were shapely increased from 7.9% in C3 to 24.6% in C4.The average RFV(relative feed value) of S5 was the highest(143.7),and the lowest values were found in S4 and S1(118.2 and 120.9).The RFV values of 5 forage species were positively related to fertilizaiton levels.These results could be useful for variety selection of tropical leguminous forages and making appropriate decisions of harvesting time and fertilization amount.

This study was carried out to evaluate fermentation quality of mixed silages of tall fescue and common vetch. The treatments were as follows: CK (100% tall fescue), 85%tall fescue+15%common vetch (C15), 70%tall fescue+30%common vetch (C30) and 55%tall fescue+45%common vetch (C45). The laboratory silos were opened on 7, 24, 45 and 60 days after ensiling in triplicate and the fermentation quality was analyzed. Based on the results, the contents of the lactic acid and water soluble carbohydrate decreased and the values of pH and NH ₃-N/TN increased significantly with increasing rate of common vetch in mixed silages ( P<0.05). At the end of ensiling, the values of pH (4.72) and NH ₃-N/TN (96.19 g穔g ^-1 TN) of C45 were higher significantly than other treatments ( P<0.05), the contents of the dry matter, lactic acid and the water soluble carbohydrate were lower significantly than other treatments ( P<0.05), and the crude protein was not significant difference as compared with C30. However, all treatments showed little amounts of butyric acid and propionic acid during ensiling. In conclusion from the present study, that mixing 70% tall fescue and 30% common vetch are recommended for fermentation quality and utilization efficacy.

To evaluate effects of adding molasses and urea on the fermentation quality of napier grass ( Pennisetum purpureum Schumach.) silage, napier grass harvested at 65 days (elongation stage) was ensiled in laboratory silos for 3, 7, 14, and 30 days at the ambient temperature. Four treatments included: no additives (control), 4% molasses (M), 0.4% urea (U), and 4% molasses+0.4% urea (MU). Samples were taken for analyzing fermentation quality after the silos were opened. Results showed that the control decreased fermentation quality during the later stage (14~30 d) of ensiling. The treatment U mainly produced acetic acid and butyric acid, and significantly increased pH and NH ₃-N/total nitrogen values compared with control( P<0.05). Both treatment M and MU significantly increased water soluble carbohydrate and lactic acid contents ( P<0.05), maintained a low level of butyric acid (<0.3 g穔g ^-1 DM) and constantly kept high value of lactic acid/acetic acid over the fermentation process. In final silages, both treatment M and MU had significantly lower neutral detergent fiber and acid detergent fiber contents ( P<0.05), and treatment MU had significantly higher crude protein content compared with control ( P<0.05). In conclusion, adding 4% molasses or the combination of 4% molasses with 0.4% urea improved fermentation quality, which promoted degradation of structural carbohydrate, and the combination of 4% molasses with 0.4% urea increased crude protein content of napier grass silage.

Plant growth promoting rhizobacteria (PGPRs) exist in soil or are attached to plant roots with the functions of growth promotion and yield improvement. In addition,PGPRs can enhance plant resistance to biotic and abiotic stresses. Nowadays,with the development of green and sustainable agriculture,microbial fertilizer has become a new type of popular of fertilizer. Therefore,researches on isolation and characterization of PGPRs,their interaction with plants and the development of microbial fertilizer containing PGPRs are attracting more and more attentions. In this paper,the research advances on PGPRs,including their growth promotion mechanisms (nitrogen fixation,phosphorus solubilization,potassium releasing,iron solubilization,plant hormone secretion,release of volatile organic compounds etc..) and tolerance enhancement of biotic stresses (pathogens and pests) and abiotic stresses (drought,salinity and heavy metals),were reviewed. Finally,the research directions on PGPRs in the future were prospected.

According to the pollution problems in tissue culture of Italian ryegrass seed explants,tissue culture was carried out by this study using the mature seeds of Italian ryegrass as explants.The pollutants from tissue culture were purified and cultured and the methods of decreasing pollution were studied.The results show that Penicillium, Aspergillus, Trichoderma, Mucor, Rhizop us, Enterobacter, and Pseudomonas were the main microbes harassing the tissue culture of Italian ryegrass.The best sterilization method of explants was to immerse the seeds in soapsuds for 6 hours,and then surface sterilization for 2 minutes by alcohol(concentration 75%),and at last soak in the sodium hypochlorite(0.1%) for 1 hour.The results also indicate that adding 70 mg/L nystatin,20 mg/L ampicillin sodium,and 0.1% sodium hypochlorite to the culture medium could control the pollution problem effectively.The two methods above had little influence on the differentiation of materials.

The experiment was carried out to evaluate the effects of adding propionic acid,lactic acid bacteria,and their combination on the fermentation quality and residual water soluble carbohydrate content of Italian ryegrass( Lolium multiflorum Lam.)silage.The treatments were as follows: Control(no addition);Lactic acid bacteria addition(LAB);Propionic acid addition at 0.4%(PA4);Propionic acid addition at 0.5%(PA5);PA4 ₊ LAB;PA5 ₊ LAB;all the additions were made on the fresh weight basis of Italian ryegrass.The DM content was not significantly different among all treatments,however,the pH tended to decrease,and the lactic acid content showed significantly( P<0.05)higher in all addition treatments in comparison with control.PA5 and PA5 ₊LAB treatments showed significantly( P<0.05)higher lactic acid content than the PA4 and PA4 ₊LAB treatments and there were no significant difference between PA and PA+LAB treatment with the same PA adding rate.PA and PA ₊ LAB treatments showed significantly( P<0.05)higher lactic acid/acetic acid than that of control and LAB addition,PA alone significantly( P<0.05)higher than PA+LAB treatment,and there was no significant difference between control and LAB treatment.PA and PA ₊ LAB treatments resulted in significantly( P<0.05)lower contents of acetic acid and butyric acid and NH ₃-N/total N and significantly( P<0.05)higher contents of propionic acid and residual water soluble carbohydrate in comparison with control and LAB treatment.In summary,addition of propionic acid could depress the undesirable bacterial activities,decrease the water-soluble carbohydrates loss,and promote lactic acid fermentation.

The ‘black soil land’ degraded grassland is the unique result of global grassland degradation's behavior in the Sanjiangyuan region of Tibetan plateau that had severely reduced the ecological function and pastoral industry in the Sanjiangyuan region. Based on the investigation of more than 290 publications and project repots in recent ten years, the authors reviewed the main studys and progresses in restoring engineering of ‘black soil land’ degraded grassland. This review discussed more about some new theory views, such as ‘black soil land’ second emergence, hydrothermal-hole effect of ‘black soil land’, temporary-steady state of ‘black soil land’ sown grassland etc. For the technique of restoration and rehabilitation, the author proposed some future technique, such as the technique system of ‘regional separation-vegetation classification-degradation degree-restoring phase regulation’,more species numbers mixed (>10) of seed materials for artificial plant community construction, human regulation of launching and inducing self-restoration for ‘black soil land’ sown grassland vegetation, and self-restoration ability and the near-nature restoration model, launching the second background of investigation for ‘black soil land’ in time, developing the low-cost model of restoration, then that can promote sustainable ecological building in the region Sanjiangyuan.

The aim of the experiment was to evaluate the effects of adding cornzyme on the fermentation qualities and carbohydrate contents of napiergrass silages.There was the control and four treatments of different cornzyme addition ratios as follows:(1) E1:cornzyme addition at 0.5 mL·kg-1,(2) E2:at 1.0 mL·kg ^-1,(3) E3:at 1.5 mL·kg ^-1,(4) E4:at 2.0 mL·kg ^-1 based on fresh weight of napiergrass.The results showed that all treatments had good fermentation quality with low pH value(4.28-3.76) and NH3-N/total N ratio,none or only small amounts of propionic acid and butyric acid,high ratio of lactic acid/acetic acid(2.94-13.46),and lactic acid content(45.00-95.41 g·kg ^-1 DM).Cornzyme addition significantly increased the ratio of lactic acid/acetic acid and the contents of lactic acid and water soluble carbohydrate( P<0.05);and significantly decreased the pH values and the contents of acetic acid and total volatile fatty acids in comparison with the control( P<0.05).The contents of neutral detergent fibre(NDF) and acid detergent fibre(ADF) tended to decrease in silages with cornzyme addition.When increasing the adding rates of cornzyme,the fermentation quality and water soluble carbohydrate content were further increased,however,NDF and ADF decreased.

The cell wall component and ultra-structure of plant were compared between brittleness mutation(BM) rice obtained by seed gamma-ray(γ) treatment and its wild type from japonica variety Zhonghua-11 in this study.The cellulose content in leaf,stem,and root of BM-rice significantly decreased( P<0.01) by 18.99%,37.29% and 23.34% compared with those of wild type,respectively,while the hemi-cellulose content in leaf,stem and root for BM-rice significantly increased( P<0.01) by 46.07%,85.26% and 61.96%,respectively.The leaf parenchyma of BM-rice was much larger than that of wild type rice by the observation of SEM.For the BM-rice,the sclerenchyma of leaves was shrunken,vascular bundle of leaves was reduced,the strumae of outer epidermis of stem was sparse and the link of phloem of root was loosed and dispersed.The hiberarchy of sclerenchyma cell wall of BM-rice leaf was not obvious by the observation of TEM.Besides,the arrangement of parenchyma cells of BM-rice stem was disordered and the exterior of parenchyma cell wall of BM-rice root was knaggy.In conclusion,BM-rice has potential advantages in utilization as a fodder-rice.

Using the method of PEG-6000 to simulate drought stress,the germination rate and germination index and other indexes of ten herbaceous plant seeds growing in Ningxia coal base after preliminary investigation were measured to compare their drought resistance during germination. The results showed that different PEG concentrations treatments had different effects on seed germination of herbaceous plants. With the increase of PEG drought stress degree,the germination potential,germination rate,germination index,radicle length and radicle diameter of seeds decreased generally;Among them,PEG (5%) with low concentration had obvious promoting effects on the germination potential of Astragalus adsurgens Pall.the germination rate of Artemisia desertorum Spreng. Syst. Veg.,the radicle length of Glycyrrhiza uralensis Fisch. and the radicle diameter of Althaea rosea (Linn.) Cavan. Compared with the control,under the treatment with PEG concentration of 15%,the germination rate and germination potential of Medicago sativa L., Althaea rosea (Linn.) Cavan. and Trifolium repens L. decreased greatly;When the PEG concentration was 20%,the germination rate and germination potential of Sophora alopecuroides L., Medicago sativa L., Suaedaglauca (Bunge) Bunge.,and Trifolium repens L. were greatly reduced. The method of membership function was used to evaluate the drought resistance of ten herbaceous plants in germination period,the order of drought resistance was Glycyrrhiza uralensis Fisch. > Melilotus suaveolens Ledeb. > Suaedaglauca (Bunge) Bunge. > Agriophyllum squarrosum (Linn.) Moq. > Medicago sativa L. > Sophora alopecuroides L. > Artemisia desertorum Spreng. Syst. Veg. > Astragalus adsurgens Pall. > Althaea rosea (Linn.) Cavan. > Trifolium repens L..

Grassland is an important ecosystem and a natural ecological security barrier in the north of China with its important ecological and production values. In recent years, due to the unreasonable use of grasslands and abnormal changes in climate, grassland pests have been aggravated year by year, which seriously restricted the livestock production and ecological civilization construction in China. Based on historical data, this article summarized the characteristics of China grassland pests with many types, strong damages, and heavy losses, analyzed the staged effects of prevention and control, and objectively pointed out the current prevention and control work's lack of monitoring capabilities, funding, equipment, scientific research support, and lagging policies and regulations, and other major issues. It then systematically put forward working goals and specific measures for strengthening grassland pest control in terms of rationalizing management systems, strengthening system construction, improving monitoring and early warning levels, innovating control mechanisms and technologies, and increasing publicity and training efforts, which provide ideas for the next step in grassland biological disaster prevention and control.

This study was carried out to evaluate the effects of wilted,pre-fermented juice(PFJ) of epiphytic lactic acid bacteria,and wilted+PFJ on the fermentation qualities and residual water soluble carbohydrate(WSC) of Hybrid Pennisetum( Pennisetum americanum× P.purpureum) silage.The treatments were as follows: control(C),wilted(W),PFJ addition,wilted+PFJ on fresh weight basis of Hybrid Pennisetum,respectively.Based on results,control had low pH(4.09) and high lactic acid content(79.80 g/kg DM),and fermentation was clearly dominated by lactic acid bacteria.W treatment showed significantly( P<0.05) higher pH and significantly( P<0.05) lower lactic acid than the control indicating that although lactic acid bacteria have a relatively high tolerance to low moisture conditions,and lactic acid fermentation was inhibited in W treatment silage.Ammonia-N /total nitrogen(AN/TN),butyric acid,propionic acid,total volatile fatty acid(VFAs) and pH decreased or decreased significantly,whereas lactic acid /acetic acid,lactic acid,WSC increased significantly in both PFJ and W+PFJ treatments compared with control( P<0.05).These indicated that PFJ and W+PFJ treatments not only inhibited the activity of clostridia and other undesired microorganisms,but decreased protein degradation.However,they also stimulated homofermentative lactic acid bacteria activity,which decreased the loss of WSC,greatly increased the efficiency of WSC utilization by lactic acid bacteria,and further improved the fermentation quality.Wilted+PFJ treatment is best for improving the fermentation quality of Hybrid Pennisetum silage in this experiment.

To evaluate effect of adding formic acid on fermentation quality of napier grass ( Pennisetum purpureum Schumach.), it was ensiled in laboratory silos for 0.5, 1, 2, 3, 5, 7, 14, and 30 days at the ambient temperature. The formic acid was added at levels of 0 (control), 2.2, 4.4 and 6.6 mL穔g ^-1 on fresh weight basis, respectively. Samples were taken for analyzing fermentation quality after the silos were opened. Results showed that control attained a good fermentation quality with no butyric acid produced. Compared with the control, formic acid addition quickly acidified napier grass silage, and significantly increased water soluble carbohydrate content ( P<0.05), and the effects increased as the addition volume increased. NH ₃-nitrogen/total nitrogen of silage treated with 2.2 mL穔g ^-1 formic acid increased rapidly after 2 days of ensiling and significantly higher than control after 3 days ( P<0.05), and butyric acid began to be detected from d 7 of ensiling. There were no lactic acid and volatile fatty acids produced and the lowest NH ₃-N/total nitrogen value (<12 g穔g ^-1 TN) in both silages treated with 4.4 and 6.6 mL穔g ^-1 formic acid. In conclusion, adding 2.2 mL穔g ^-1 formic acid had a decreasing acidification which lowered the fermentation quality and nutritive value in the later ensiling period, whereas adding 4.4 mL穔g ^-1 formic acid was sufficiently high to effectively conserve nutrients of napier grass.

Foraging behavior of goats was investigated under different grazing pressure and different grazing time in South China.Results showed both ingesting times and ingesting steps were decreased under lower grazing pressure index,whereas bite numbers per step,rate of ingestion,intake per bite,daily intake,time of rumination were significantly increased at the same time.There was little effect on other behaviors.In September,ingesting times and ingesting steps were the least and intake per bite was maximum among all tested times.Bite numbers per step in June was significantly less than that of other months.The rate of ingestion was significantly increased in October.Time of rumination,chewing time per ruminating food bolus was the longest in October.Both chewing rate and interval time had fewer differences between two ruminating food bolus in different month.

To improve the fermentation quality of mixed silage of oat straw and perennial ryegrass and enhance the utilization efficiency of oat straw resource in Tibet, the mixture of oat straw and perennial ryegrass (4:6) were ensiled with different additives. The treatments were designed as follows: control, lactic acid bacteria (LAB, 1×10 ⁶ cfu·g ^-1 FW), molasses (4% FW) and LAB + molasses, six reduplicate silos per treatment. The fermentation quality was analyzed after ensiling 60 days. Molasses or/and LAB additives significantly decreased the pH value, ammonia/total N (AN/TN), propionic and butyric acid contents of mixed silage ( P<0.05), while significantly increased the lactic/acetic acid ratio and lactic acid contents of mixed silage compared to control silage ( P<0.05). The silage added with molasses had higher lactic acid and water soluble carbohydrate (WSC) contents than the one added with LAB. However, there was no significantly different fermentation quality between the silage added with molasses and the one added with LAB + molasses. Therefore, it was suggested that 4% molasses additive was suitable to improve the fermentation quality of mixed silage of oat straw and perennial ryegrass in Tibet.

Pennisetum Rich.plays an integral,important role as a forage crop regarding soil improvement,water and soil conservation.This review summarizes recent progress for improvement of Pennisetum,including its botanical characteristics,variety resources,ecological distribution,genetic diversity,physiology and biochemistry,variety breeding,cultivation techniques and practical applications.Additionally,current problems and logical research directions for Pennisetum are summarized to provide reference with its related research.