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991.
在长白山针阔叶混交林下,红松、蒙古栎、春榆、白桦、山杨、色木及紫椴叶分解至300天时,其重量损失百分数分别为24.2,37.6,30.8,44.47,50.6及55.6。在分解过程中,每种叶子的重量损失同该叶子的木质素、水溶性物质、全碳及全氮的变化成线性相关(R=0.99**)。在叶子分解前期,木质素、N素的绝对量有所增加,而水溶性物质则急剧减少。除紫椴叶外,其它几种叶子在分解过程中氮的含量有一定增加。但是,当红松、蒙古栎、春榆、白桦、山杨及色木叶中N素浓度分别为0.96%,1.41%,2.38%,1.67%,1.32%及1.32%时,则开始了N素的矿化释放。 相似文献
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Abstract The susceptibility and virulence of entomopathogenic fungus Metarhizium anisopliae var. acridum to the stages of brown planthopper (BPH), Nilaparvata lugens (Stål) and whitebacked planthopper (WBPH), Sogatella furcifera (Horvath) were investigated under laboratory conditions. Three dosages of M. anisopliae var. acridum ranging from 10.5, 116.3 and 1027.1 conidial/mm2 were used in the experiment. The tested stages of host included three developmental stages, young nymphs (1–2 instars), old nymphs (3–5 instars) and adults. It was found that all tested stages of the planthoppers were susceptible to the fungal infection. The degree of virulence LT50 of M. anisopliae var. acridum against young nymphs of N. lugens are >21, 20.82 and 16.55, respectively with the 3 dosages, the LT50 of the fungus against the old nymphs are 17.68, 15.49 and 13.98, respectively with the 3 dosages; the LT50 of the fungus against the adults are 17.10, 12.57 and 9.14 respectively with the 3 dosages. The degree of virulence LT50 of M. anisopliae var. acridum on young nymphs of S. furcifera are >21, 17.29 and 13.13, respectively with the 3 dosages ; the LT50 of the fungus against the old nymphs are 16.94, 15.02 and 13.03, respectively with the 3 dosages; the LT50 of the fungus against the adults are 12.78, 10.16 and 7.64, respectively with the 3 dosages. Adults were more susceptible to M. anisopliae var. acridum infection than their nymphs and the young nymphs were most resistant to the fungal infection. The cumulative mortality of each stage was dosage-dependent. Of all the developmental stages, WBPH was more susceptible than BPH to M. anisopliae var. acridum infection with the same dosages. 相似文献
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Geng Lingjun Chen Shenglan Sun Xiaoman Hu Xuechao Ji Xiaojun Huang He Ren Lujing 《Bioprocess and biosystems engineering》2019,42(1):71-81
Bioprocess and Biosystems Engineering - The ω-3/long-chain polyunsaturated fatty acids (LC-PUFAs) play an important role in human health, but they cannot be synthesized in sufficient amounts... 相似文献
998.
Ran Cheng Gulaqa Anwari Zhu Jing Wang Xiaowei Zhang Siqi Geng Yanqiu Guo Liying Jin Feng Shao Xiwen 《Journal of Plant Growth Regulation》2020,39(1):370-377
Journal of Plant Growth Regulation - Saline–sodic is one of the major conditions threatening crop production. Biochar application could alleviate the adverse impacts of saline–sodic... 相似文献
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Xu Xun Meng Qing-Lin Geng Mu-Fan Ren Ning-Ning Zhou Lian Du Yu-Su Cai Zhe Wang Mei-Xia Wang Xin Wang Xiu-Hua Han Jing-Dan Jiang Shuai Jing Chun-Yan Liu Rong Zheng Xiao-Ming Yang Qing-Wen Zhang Fu-Min Ge Song 《中国科学:生命科学英文版》2020,63(11):1714-1724
Science China Life Sciences - It is of critical importance for our understanding of speciation process to determine the forms of reproductive isolation and their relative importance in species... 相似文献
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