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21.
Yang SONG Chen ZHU Waseem RAZA Dongsheng WANG Qiwei HUANG Shiwei GUO Ning LING Qirong SHEN 《农业科学与工程前沿(英文版)》2016,3(3):249
Grafting is commonly used to overcome soil-borne diseases. However, its effects on the rhizodeposits as well as the linkages between the rhizosphere chemical niche and microbiome remained unknown. In this paper, significant negative correlations between the bacterial alpha diversity and both the disease incidence (r = −0.832, P = 0.005) and pathogen population (r = −0.786, P = 0.012) were detected. Moreover, our results showed that the chemical diversity not only predicts bacterial alpha diversity but also can impact on overall microbial community structure (beta diversity) in the rhizosphere. Furthermore, some anti-fungal compounds including heptadecane and hexadecane were identified in the rhizosphere of grafted watermelon. We concluded that grafted watermelon can form a distinct rhizosphere chemical niche and thus recruit microbial communities with high diversity. Furthermore, the diverse bacteria and the antifungal compounds in the rhizosphere can potentially serve as biological and chemical barriers, respectively, to hinder pathogen invasion. These results not only lead us toward broadening the view of disease resistance mechanism of grafting, but also provide clues to control the microbial composition by manipulating the rhizosphere chemical niche. 相似文献
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Qasim Ali Muhammad Tariq Javed Ali Noman Muhammad Zulqarnain Haider Muhammad Waseem Naeem Iqbal 《Archives of Agronomy and Soil Science》2018,64(1):84-102
Drought stress hampers firm crop stand establishment and yield in arid and semiarid regions. The present study was conducted to examine the drought tolerance of various mung bean cultivars/lines based on the seed germination characteristics in relation with the seedling’s antioxidative potential and nutrient uptake. Activities of germination enzymes, seed germination attributes, seedling biomass production and nutrient uptake of studied cultivars/lines were adversely affected due to PEG-induced drought but the total soluble proteins (TSP) and malondialdehyde (MDA) contents were increased. The activities of catalse (CAT) and ascorbate peroxidase (APX) increased in all cultivars/lines being the maximum in cv./line NM-2006 and 8005. The activities of superoxide dismutase (SOD) and peroxidase (POD) were increased in cv./line NM-2006 and 8005 under drought condition. The ascorbic acid (AsA) and total phenolic content (TPC) decreased and total flavonoid content (TFC) increased in all cultivars/lines due to drought. Significant reduction in N, P, K, Ca and Mg was found in all cvs./lines but Fe remain unchanged. In conclusion, cultivars/lines NM-2006, 8005 were recommended as drought tolerant and 97,006 and 97,001 as drought sensitive ones. The study outcomes will likely be helpful for the farmers growing mung bean in rain fed areas for the better productivity. 相似文献
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Genetic architecture of seedling drought tolerance is complex and needs to be better understood. To address this challenge, we developed a protocol to identify the most promising drought-tolerant genotypes at the seedling stage in winter wheat. A population of 146 recombinant inbred lines (F9) derived from a cross between wheat cultivars, ‘Harry’ (seedling drought tolerant) and ‘Wesley’ (seedling drought susceptible) were used in this study. All genotypes were sown in three replications in a randomized complete block design under controlled conditions in a greenhouse. Seven traits were scored and grouped into tolerance traits; days to wilting, leaf wilting, and stay green and survival traits; days to regrowth, regrowth, drought survival rate, and recovery after irrigation. Three selection indices were calculated (1) tolerance index, (2) survival index, and (3) drought tolerance index (DTI). The same set of genotypes were also tested for grain yield in two low rainfall environments for two seasons. High genetic variation was found among all genotypes for all seedling traits scored in this study. Correlations between tolerance and survival traits were weak or did not exist. Heritability estimates ranged from 0.53 to 0.88. DTI had significant phenotypic and genotypic correlations with all seedling traits. Genotypes were identified with a high drought tolerance at the seedling stage combined with high grain yield in low rainfall. Breeding for tolerance and survival traits should be taken into account for improving winter wheat drought tolerance at seedling stage. The selected genotypes can be used for to further improve drought tolerance in high yielding wheat for Nebraska. 相似文献
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Hong-sheng Wu Jia Luo Waseem Raza Yan-xia Liu Mian Gu Gao Chen Xiao-feng Hu Jing-heng Wang Ze-sheng Mao Qi-rong Shen 《Scientia Horticulturae》2010
Allelochemicals from root exudates or decaying residues of watermelon plant may be related to watermelon fusarium wilt. The aim of this work was to study the effect of an artificially applied allelochemical, ferulic acid, on in vitroFusarium oxysporum f. sp. niveum (FON), a causal pathogen of plant wilting in the laboratory setting. 相似文献
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Cinnamic acid inhibits growth but stimulates production of pathogenesis factors by in vitro cultures of Fusarium oxysporum f.sp. niveum 总被引：1，自引：0，他引：1
Wu HS Raza W Fan JQ Sun YG Bao W Shen QR 《Journal of agricultural and food chemistry》2008,56(4):1316-1321
Long-term monoculture of watermelon leads to frequent occurrence of watermelon fusarium wilt caused by Fusarium oxysporum f.sp. niveum (FON). Some allelochemicals contained in watermelon root exudates and decaying residues are possibly responsible for promoting the wilt disease. The purpose of this study was to evaluate the allelopathic effect of artificially applied cinnamic acid on FON. Results demonstrated that hyphal growth of FON was strongly inhibited by cinnamic acid. At the highest concentration of cinnamic acid, the biomass in liquid culture was decreased by 63.3%, while colony diameter, conidial germination on plates, and conidial production in liquid culture were completely inhibited. However, mycotoxin production and activity of phytopathogenic enzymes were greatly stimulated. Mycotoxin yield, pectinase activity, proteinase activity, cellulase activity, and amylase activity were increased by 490, 590, 760, 2006, and 27.0%, respectively. It was concluded that cinnamic acid dramatically stimulated mycotoxin production and activities of hydrolytic enzymes by FON but inhibited growth and germination of FON. The findings presented here indicate that cinnamic acid is involved in promoting watermelon fusarium wilt. 相似文献
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OBJECTIVE: To evaluate the effect of two types of iron pots on haemoglobin (Hb) and serum ferritin (SF) concentrations in young children (6-24 months), adolescent girls (11-15 years) and women of reproductive age (15-44 years), whose households were provided with iron pots for cooking food over a period of 6 months, compared with controls.Design and methodsWe randomly assigned 161 households including 339 individuals from the three subgroups to cast iron pots, blue steel pots or oral iron supplements (control). In the control group, children received micronutrient Sprinklestrade mark, and adolescent girls and women received iron tablets daily for 6 months. We measured Hb, SF and C-reactive protein concentrations at baseline and 6 months, and compared groups using regression models. RESULTS: Anaemia prevalence (Hb < 110 g l-1 in infants, Hb < 120 g l-1 in girls or women) was 47% (cast iron group), 50% (blue steel group) and 50% (control) at baseline. At 6 months, there were no significant differences in Hb concentrations among groups; however, differences in SF concentrations were significant (P < 0.0001) - the control group had higher SF concentrations compared with the groups using iron pots. Also, differences in the prevalence of iron-deficiency anaemia (IDA; anaemia plus SF < 15 mug l-1) were almost significant between cast iron and control groups (P = 0.08), and blue steel and control groups (P = 0.05).ConclusionThere is no evidence that iron cooking pots are effective against IDA. Further research is warranted to determine whether the iron leached from the pots is bioavailable. 相似文献
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Gogi MD Sarfraz RM Dosdall LM Arif MJ Keddie AB Ashfaq M 《Pest management science》2006,62(10):982-990
Field efficacies of two insect growth regulators (IGRs) at two recommended application rates, buprofezin at 370 and 555 g AI ha(-1) and lufenuron at 37 and 49 g AI ha(-1), were determined against the sweet potato whitefly, Bemisia tabaci (Gennadius), and the cotton bollworm, Helicoverpa armigera (Hübner), in experimental plots of cotton at the Directorate of Cotton Research, Faisalabad, Pakistan. Adverse effects of the IGRs on populations of associated arthropod predators, namely geocorids, chrysopids, coccinellids, formicids and arachnids, were also assessed. Both IGRs significantly reduced populations of B. tabaci at each application rate 24, 48 and 72 h after treatment, and higher doses were more effective than lower doses. Buprofezin was not effective against H. armigera at any tested dose for any time of treatment in any spray. Lufenuron applied at 37 and 49 g AI ha(-1) effectively suppressed H. armigera populations, resulting in significant reductions in crop damage. At lower doses, both IGRs appeared safe to predator populations, which did not differ significantly in IGR-treated versus untreated control plots. Population densities of formicids and coccinellids were significantly lower at high concentrations of both IGRs in treatment plots, possibly as a result of reduced prey availability. The potential role of buprofezin and lufenuron for control of B. tabaci and H. armigera in a spray programme and the likelihood of direct toxic effects of IGRs on predatory fauna of cotton are discussed. 相似文献
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Lee Jae Eun Azam Muhammad Rehman Saif Ur Waseem Muhammad Anjum M. Naveed Afzal Arslan Cheema M. J. M. Mehtab Muhammad Latif Muhammad Ahmed Rehan Umar Muhammad Sarwar Abid Rehman Syed Aziz Ur 《Paddy and Water Environment》2022,20(1):117-135
Climate change in Pakistan has a great impact on the spatial and temporal variation of precipitation and ultimately alters the frequency and duration of droughts. In this study, spatial and temporal trend analyses of precipitation and droughts were observed at 58 meteorological stations across Pakistan from 1981 to 2018. The existing trend analysis methods were evaluated to address the issue of serial correlation in the climatic data. Results of precipitation analysis showed significant decreasing trends in winter (November, December) and significant increasing trends were observed in summer (June and September) at a confidence level of 95 percent. The magnitude of the precipitation trends showed the highest variation during summer season and the least variation in winter season. Rotated Principal Component (RPC) analysis showed the severe droughts (high positive loading) in southeastern side (Sindh province) of Pakistan due to lack of summer rains. Furthermore, variance correction approaches are identified as the most suitable in coping with the effect of serial correlation. The highest drought frequencies were observed in the southern areas of Pakistan and the drought events are expected to occur more frequently in the late winter, early spring, and early autumn, while droughts were expected to occur least frequently in summer.
相似文献30.