The control effects and application methods of Pleurotus ostreatus on the peanut root-knot nematode disease, Meloidogyne arenaria, were systematically studied in the greenhouse. Results of pot experiments showed that ...The control effects and application methods of Pleurotus ostreatus on the peanut root-knot nematode disease, Meloidogyne arenaria, were systematically studied in the greenhouse. Results of pot experiments showed that P. ostreatus could effectively reduce the 2nd-instar population density in the soil, and the larva reduced by 80% compared with the control. P. ostreatus could markedly lower the infecting number of the peanut root-knot nematodes, the nematode density inside the root knots declined by 40.00% -82.64%, and the peanut root knots also reduced by 86.96% - 94. 03%. The fungus could defer the initial infection of M. arenaria to the roots, the epidemic rate of the peanut root-knot nematode disease was significantly cut down, and the increase of root-knot changed from the way of Logistic curve in the control to the way of linear curve in the treatment. The final control effectiveness was about 80%. The results of pot trial also indicated that the control effectiveness is closely related to the application time and the amount of this fungus. The key factor affecting control effectiveness was the application time of P. ostreatus in the soil and the suitable time was 20 days before sowing.展开更多
Solution culture was conducted in order to understand accumulation characteristics and chemical forms of Pb in Arenaria orbiculata （A. orbiculata） and the response of root exudates to Pb addition. The results showed...Solution culture was conducted in order to understand accumulation characteristics and chemical forms of Pb in Arenaria orbiculata （A. orbiculata） and the response of root exudates to Pb addition. The results showed that： 1） Pb contents in the shoot and root of A. orbiculata increased with increasing in Pb concentrations in solution. 2） The contents of Pb chemical forms under Pb addition followed as： HAc extractable fraction＇（FriAC）〉 HC1 extractable fraction （FHcl）〉 NaCl extractable fraction （FNacl） 〉 ethanol-extractable fraction （FE） 〉 water extractable fraction （Fw）. 3） Increased Pb level in the medium caused increases in Pb contents in the four subcellular fractions of shoots and roots, with most accumulation in FIV （Fraction ＇IV, sbluble fraction） in shoots and FI （Fraction I, cell wall fraction） in roots. 4） Contents of soluble sugar and free amino acid of root exudates increased with increasing Pb concentration in solution. Significantly positive correlations between Pb and contents of soluble sugar and free amino acid were observed. 5） With Pb concentrations in solution, low molecular weight organic acids （LMWOAs） contents followed the tendency： tartaric acid 〉 acetic acid 〉 malic acid 〉 citric acid. Significantly positive correlation was observed between Pb and citric acid contents. The results indicate that soluble sugars, free amino acid and citric acid in root exudates of A.orbiculata facilitate the absorption and accumulation of Pb, which exist in NaCl-, HCI- and HAc- extractable Pb forms, FI and FIV fractions, resulting in tolerance of A.orbiculata to Pb.展开更多
To further investigate the cyclopeptldes of the Caryophyllaceae family, two new cyclopeptldes, named Arenarlphilin E （compound 1） and Arenariphilin F （compound 2）, were obtained from Arenaria oreophUe J. D. Hooker...To further investigate the cyclopeptldes of the Caryophyllaceae family, two new cyclopeptldes, named Arenarlphilin E （compound 1） and Arenariphilin F （compound 2）, were obtained from Arenaria oreophUe J. D. Hooker using some Isolation methods, e. g. normal and reverse silica gel. By detailed spectroscopic analysis, such as FAB^＋-MS, 1 D NMR, 2D NMR, the structures of Arenariphilin E （compound 1） and Arenariphilln F （compound 2） were determined as cyclo（lle^1-Gly-Val^1-Ala-Leu-lle^3-lle^2-Val^2-Pro） and cyclo（Pro^2-Pro^1-Gly^2-lle-Val-Leu-Gly^1-AiaThr- Gly^3）, respectively.展开更多
文摘The control effects and application methods of Pleurotus ostreatus on the peanut root-knot nematode disease, Meloidogyne arenaria, were systematically studied in the greenhouse. Results of pot experiments showed that P. ostreatus could effectively reduce the 2nd-instar population density in the soil, and the larva reduced by 80% compared with the control. P. ostreatus could markedly lower the infecting number of the peanut root-knot nematodes, the nematode density inside the root knots declined by 40.00% -82.64%, and the peanut root knots also reduced by 86.96% - 94. 03%. The fungus could defer the initial infection of M. arenaria to the roots, the epidemic rate of the peanut root-knot nematode disease was significantly cut down, and the increase of root-knot changed from the way of Logistic curve in the control to the way of linear curve in the treatment. The final control effectiveness was about 80%. The results of pot trial also indicated that the control effectiveness is closely related to the application time and the amount of this fungus. The key factor affecting control effectiveness was the application time of P. ostreatus in the soil and the suitable time was 20 days before sowing.
文摘Solution culture was conducted in order to understand accumulation characteristics and chemical forms of Pb in Arenaria orbiculata （A. orbiculata） and the response of root exudates to Pb addition. The results showed that： 1） Pb contents in the shoot and root of A. orbiculata increased with increasing in Pb concentrations in solution. 2） The contents of Pb chemical forms under Pb addition followed as： HAc extractable fraction＇（FriAC）〉 HC1 extractable fraction （FHcl）〉 NaCl extractable fraction （FNacl） 〉 ethanol-extractable fraction （FE） 〉 water extractable fraction （Fw）. 3） Increased Pb level in the medium caused increases in Pb contents in the four subcellular fractions of shoots and roots, with most accumulation in FIV （Fraction ＇IV, sbluble fraction） in shoots and FI （Fraction I, cell wall fraction） in roots. 4） Contents of soluble sugar and free amino acid of root exudates increased with increasing Pb concentration in solution. Significantly positive correlations between Pb and contents of soluble sugar and free amino acid were observed. 5） With Pb concentrations in solution, low molecular weight organic acids （LMWOAs） contents followed the tendency： tartaric acid 〉 acetic acid 〉 malic acid 〉 citric acid. Significantly positive correlation was observed between Pb and citric acid contents. The results indicate that soluble sugars, free amino acid and citric acid in root exudates of A.orbiculata facilitate the absorption and accumulation of Pb, which exist in NaCl-, HCI- and HAc- extractable Pb forms, FI and FIV fractions, resulting in tolerance of A.orbiculata to Pb.
基金Supported by the Yunnan Provincial Natural Science Foundation of China (2001 B055M)
文摘To further investigate the cyclopeptldes of the Caryophyllaceae family, two new cyclopeptldes, named Arenarlphilin E （compound 1） and Arenariphilin F （compound 2）, were obtained from Arenaria oreophUe J. D. Hooker using some Isolation methods, e. g. normal and reverse silica gel. By detailed spectroscopic analysis, such as FAB^＋-MS, 1 D NMR, 2D NMR, the structures of Arenariphilin E （compound 1） and Arenariphilln F （compound 2） were determined as cyclo（lle^1-Gly-Val^1-Ala-Leu-lle^3-lle^2-Val^2-Pro） and cyclo（Pro^2-Pro^1-Gly^2-lle-Val-Leu-Gly^1-AiaThr- Gly^3）, respectively.
