Both yield and quality of Lanzhou lily(Lilium davidii var. unicolor) are seriously affected by continuous cropping. We attempted to understand the effects of intercropping on the obstacles associated with continuous c...Both yield and quality of Lanzhou lily(Lilium davidii var. unicolor) are seriously affected by continuous cropping. We attempted to understand the effects of intercropping on the obstacles associated with continuous cropping of Lanzhou lily(Lilium davidii var. unicolor). The changes of rhizosphere microbial biomass and diversity in interplanting and monoculturing systems were studied by using the Illumina Hi Seq sequencing technique. The contents and composition of lily root exudates were measured by gas chromatography–mass spectrometer(GC–MS). The intercropping results of Lanzhou lily showed:(1) There was no difference in the composition of the rhizosphere soil microbes at the phylum level, but the relative abundance of the microbes decreased; and the relative abundance of harmful fungi such as Fusarium sp. increased. The relative abundance of Pleosporales sp. and other beneficial bacteria were reduced. After OTU(operational taxonomic unit)clustering, there were some beneficial bacteria, such as Chaetomium sp., in the lily rhizosphere soil in the interplanting system that had not existed in the single-cropping system. We did not find harmful bacteria that had existed in the single-cropping systm in the rhizosphere soil of interplanting system. The above results indicated that the changes of relative abundance of soil fungi and bacteria in lily rhizosphere soil was not conducive to improving the ecological structure of rhizosphere soil microbes. At the same time, the microbial composition change is very complex—beneficial and yet inadequate at the same time.(2) Root exudates provide a matrix for the growth of microorganisms. Combined with the detection of root exudates, the decrease in the composition of the root exudates of the lily was probably the reason for the decrease of the relative abundance of microbes after intercropping. At the same time, the decrease of the relative content of phenolic compounds, which inhibit the growth of microorganisms, did not increase the relative content of rhizosphere soil microorganisms. Changes in amino acids and total sugars may be responsible for the growth of Fusarium sp.. The results showed that the intercropping pattern did not noticeably alleviate the obstacle to continuous cropping of Lanzhou lily, and the change of microbial biomass and diversity was even unfavorable. However, the emergence of some beneficial bacteria, the disappearance of harmful fungi, and other changes with intercropping are in favor of alleviation of obstacles to continuous cropping of Lanzhou lily.展开更多
Changes in carbohydrate, phenols, free amino acids and endogenous hormones in middle scales of Lilium davidii var.unicolor bulbs during the 101 days storage at 2, 6 and 10°C in moist sawdust were studied. The res...Changes in carbohydrate, phenols, free amino acids and endogenous hormones in middle scales of Lilium davidii var.unicolor bulbs during the 101 days storage at 2, 6 and 10°C in moist sawdust were studied. The results indicated that asthe storage time increased and the storage temperature delined, contents of starch and abscisic acid (ABA) decreasedmarkedly, and the level of total soluble sugar, phenols, gibberellic acid (GA3) and indole acetic acid (IAA) increasedsharply. In the first 34 days, the contents of the above substances changed most actively. Correlation analysis revealedthat the increase in content of total soluble sugar and phenols was respectively caused by activation of amylase andphenylalanine ammonia-lyase (PAL). During the storage, the content of free amino acids decreased, and the level ofarginine was the highest and changed most remarkably. According to the results of stepwise regression analysis and pathanalysis, we could primarily conclude that the metabolism of carbohydrates, phenols and free amino acids in the middlescales may be mainly regulated by endogenous GA3.展开更多
基金funded by Lanzhou Branch of the Chinese Academy of Sciences institutional cooperation program(2BY52BI61)the Key program of Chinese Academy of Sciences(22Y622AM1)
文摘Both yield and quality of Lanzhou lily(Lilium davidii var. unicolor) are seriously affected by continuous cropping. We attempted to understand the effects of intercropping on the obstacles associated with continuous cropping of Lanzhou lily(Lilium davidii var. unicolor). The changes of rhizosphere microbial biomass and diversity in interplanting and monoculturing systems were studied by using the Illumina Hi Seq sequencing technique. The contents and composition of lily root exudates were measured by gas chromatography–mass spectrometer(GC–MS). The intercropping results of Lanzhou lily showed:(1) There was no difference in the composition of the rhizosphere soil microbes at the phylum level, but the relative abundance of the microbes decreased; and the relative abundance of harmful fungi such as Fusarium sp. increased. The relative abundance of Pleosporales sp. and other beneficial bacteria were reduced. After OTU(operational taxonomic unit)clustering, there were some beneficial bacteria, such as Chaetomium sp., in the lily rhizosphere soil in the interplanting system that had not existed in the single-cropping system. We did not find harmful bacteria that had existed in the single-cropping systm in the rhizosphere soil of interplanting system. The above results indicated that the changes of relative abundance of soil fungi and bacteria in lily rhizosphere soil was not conducive to improving the ecological structure of rhizosphere soil microbes. At the same time, the microbial composition change is very complex—beneficial and yet inadequate at the same time.(2) Root exudates provide a matrix for the growth of microorganisms. Combined with the detection of root exudates, the decrease in the composition of the root exudates of the lily was probably the reason for the decrease of the relative abundance of microbes after intercropping. At the same time, the decrease of the relative content of phenolic compounds, which inhibit the growth of microorganisms, did not increase the relative content of rhizosphere soil microorganisms. Changes in amino acids and total sugars may be responsible for the growth of Fusarium sp.. The results showed that the intercropping pattern did not noticeably alleviate the obstacle to continuous cropping of Lanzhou lily, and the change of microbial biomass and diversity was even unfavorable. However, the emergence of some beneficial bacteria, the disappearance of harmful fungi, and other changes with intercropping are in favor of alleviation of obstacles to continuous cropping of Lanzhou lily.
基金This work was supported by the National Natural Science Foundation of China(30400307).
文摘Changes in carbohydrate, phenols, free amino acids and endogenous hormones in middle scales of Lilium davidii var.unicolor bulbs during the 101 days storage at 2, 6 and 10°C in moist sawdust were studied. The results indicated that asthe storage time increased and the storage temperature delined, contents of starch and abscisic acid (ABA) decreasedmarkedly, and the level of total soluble sugar, phenols, gibberellic acid (GA3) and indole acetic acid (IAA) increasedsharply. In the first 34 days, the contents of the above substances changed most actively. Correlation analysis revealedthat the increase in content of total soluble sugar and phenols was respectively caused by activation of amylase andphenylalanine ammonia-lyase (PAL). During the storage, the content of free amino acids decreased, and the level ofarginine was the highest and changed most remarkably. According to the results of stepwise regression analysis and pathanalysis, we could primarily conclude that the metabolism of carbohydrates, phenols and free amino acids in the middlescales may be mainly regulated by endogenous GA3.
