PDF(Pubmed)
Abstract：
BACKGROUND: Long-term continuous cropping has resulted in the frequent occurrence of fusarium wilt of watermelon (Citrullus lanatus). AMF inoculation can alleviate the continuous cropping barrier and reduce the incidence of fusarium wilt of watermelon. Our previous study found that the root exudates of mycorrhizal watermelon can enhance watermelon resistance to this disorder. It is necessary to further isolate and identify the specific compounds in root exudates of mycorrhizal watermelon and explore their control effects on fusarium wilt of continuous cropping watermelon.
RESULTS: The results of this study showed that the root system of watermelon seedlings inoculated with AMF (Funneliformis mosseae or Glomus versiforme) secreted diisooctyl phthalate (A) and dibutyl phthalate (B). Compared with water treatment, treatment with 0.1 ml/L (A1, B1), 0.5 ml/L (A2, B2) and 1 ml/L (A3, B3) of A or B significantly increased soil enzyme activities, the numbers of bacteria and actinomycetes, and the bacteria/fungi ratio in the rhizosphere. Furthermore, the Disease indexes (DI) of A1 and B3 were 25% and 20%, respectively, while the prevention and control effects (PCE) were 68.8% and 75%, respectively. In addition, diisooctyl phthalate or dibutyl phthalate increased the proportions of Gemmatimonadetes, Chloroflexi, and Acidobacteria in the rhizosphere of continuous cropping watermelon, and decreased the proportions of Proteobacteria and Firmicutes, with Novosphingobium, Kaistobacter, Bacillus, and Acinetobacter as the predominant bacteria. Compared with the water treatment, the abundance of Neosphingosaceae, Kateybacterium and Bacillus in the A1 group was increased by 7.33, 2.14 and 2.18 times, respectively, while that in the B2 group was increased by 60.05%, 80.24% and 1 time, respectively. In addition, exogenous diisooctyl phthalate and dibutyl phthalate were shown to promote growth parameters (vine length, stem diameter, fresh weight and dry weight) and antioxidant enzyme system activities (SOD, POD and CAT) of continuous cropping watermelon.
CONCLUSIONS: Lower watermelon fusarium wilt incidence in mycorrhizal watermelons was associated with phthalate secretion in watermelons after AMF inoculation. Exogenous diisooctyl phthalate and dibutyl phthalate could alleviate the continuous cropping disorder of watermelon, reduce the incidence of fusarium wilt, and promote the growth of watermelon by increasing the enzyme activities and the proportion of beneficial bacteria in rhizosphere soil. In addition, the low concentration of phthalate diisooctyl and high concentration of phthalic acid dibutyl works best. Therefore, a certain concentration of phthalates in the soil can help alleviate continuous cropping obstacles.
RESULTS: The results of this study showed that the root system of watermelon seedlings inoculated with AMF (Funneliformis mosseae or Glomus versiforme) secreted diisooctyl phthalate (A) and dibutyl phthalate (B). Compared with water treatment, treatment with 0.1 ml/L (A1, B1), 0.5 ml/L (A2, B2) and 1 ml/L (A3, B3) of A or B significantly increased soil enzyme activities, the numbers of bacteria and actinomycetes, and the bacteria/fungi ratio in the rhizosphere. Furthermore, the Disease indexes (DI) of A1 and B3 were 25% and 20%, respectively, while the prevention and control effects (PCE) were 68.8% and 75%, respectively. In addition, diisooctyl phthalate or dibutyl phthalate increased the proportions of Gemmatimonadetes, Chloroflexi, and Acidobacteria in the rhizosphere of continuous cropping watermelon, and decreased the proportions of Proteobacteria and Firmicutes, with Novosphingobium, Kaistobacter, Bacillus, and Acinetobacter as the predominant bacteria. Compared with the water treatment, the abundance of Neosphingosaceae, Kateybacterium and Bacillus in the A1 group was increased by 7.33, 2.14 and 2.18 times, respectively, while that in the B2 group was increased by 60.05%, 80.24% and 1 time, respectively. In addition, exogenous diisooctyl phthalate and dibutyl phthalate were shown to promote growth parameters (vine length, stem diameter, fresh weight and dry weight) and antioxidant enzyme system activities (SOD, POD and CAT) of continuous cropping watermelon.
CONCLUSIONS: Lower watermelon fusarium wilt incidence in mycorrhizal watermelons was associated with phthalate secretion in watermelons after AMF inoculation. Exogenous diisooctyl phthalate and dibutyl phthalate could alleviate the continuous cropping disorder of watermelon, reduce the incidence of fusarium wilt, and promote the growth of watermelon by increasing the enzyme activities and the proportion of beneficial bacteria in rhizosphere soil. In addition, the low concentration of phthalate diisooctyl and high concentration of phthalic acid dibutyl works best. Therefore, a certain concentration of phthalates in the soil can help alleviate continuous cropping obstacles.
摘要：
背景：长期连作导致西瓜枯萎病（Citrulluslanatus）频繁发生。接种AMF可以缓解西瓜连作障碍,减少枯萎病的发生。我们先前的研究发现，菌根西瓜的根系分泌物可以增强西瓜对这种疾病的抵抗力。有必要进一步分离和鉴定菌根西瓜根系分泌物中的特定化合物，并探讨其对连作西瓜枯萎病的防治效果。
结果：本研究结果表明，接种AMF（双歧杆菌或双歧杆菌）的西瓜幼苗根系分泌邻苯二甲酸二异辛酯（A）和邻苯二甲酸二丁酯（B）。与水处理相比,用0.1ml/L（A1，B1）处理，A或B的0.5ml/L（A2，B2）和1ml/L（A3，B3）显着提高了土壤酶活性，细菌和放线菌的数量，和根际中的细菌/真菌比率。此外，A1和B3的疾病指数（DI）分别为25％和20％，分别,而防控效果(PCE)分别为68.8%和75%，分别。此外,邻苯二甲酸二异辛酯或邻苯二甲酸二丁酯增加了Gemmaatimonadetes的比例，氯氟菌,连作西瓜根际的酸性细菌，并降低了变形杆菌和厚壁菌的比例，用Novoshingobium,Kaistobot,芽孢杆菌,和不动杆菌为主要细菌。与水处理相比,丰富的新蛇科，A1组杆菌和芽孢杆菌分别增加了7.33、2.14和2.18倍,分别,而B2组增加了60.05%，80.24%和1倍，分别。此外,外源邻苯二甲酸二异辛酯和邻苯二甲酸二丁酯被证明可以促进生长参数(藤蔓长度，阀杆直径,鲜重和干重)和抗氧化酶系统活性(SOD，连续种植西瓜的POD和CAT）。
结论：接种AMF后，菌根西瓜枯萎病发病率较低，与西瓜邻苯二甲酸酯分泌有关。外源邻苯二甲酸二异辛酯和邻苯二甲酸二丁酯能缓解西瓜连作障碍,减少枯萎病的发病率，并通过增加根际土壤中的酶活性和有益菌比例来促进西瓜的生长。此外,低浓度的邻苯二甲酸二异辛酯和高浓度的邻苯二甲酸二异辛酯效果最好。因此,土壤中一定浓度的邻苯二甲酸盐有助于缓解连作障碍。
结果：本研究结果表明，接种AMF（双歧杆菌或双歧杆菌）的西瓜幼苗根系分泌邻苯二甲酸二异辛酯（A）和邻苯二甲酸二丁酯（B）。与水处理相比,用0.1ml/L（A1，B1）处理，A或B的0.5ml/L（A2，B2）和1ml/L（A3，B3）显着提高了土壤酶活性，细菌和放线菌的数量，和根际中的细菌/真菌比率。此外，A1和B3的疾病指数（DI）分别为25％和20％，分别,而防控效果(PCE)分别为68.8%和75%，分别。此外,邻苯二甲酸二异辛酯或邻苯二甲酸二丁酯增加了Gemmaatimonadetes的比例，氯氟菌,连作西瓜根际的酸性细菌，并降低了变形杆菌和厚壁菌的比例，用Novoshingobium,Kaistobot,芽孢杆菌,和不动杆菌为主要细菌。与水处理相比,丰富的新蛇科，A1组杆菌和芽孢杆菌分别增加了7.33、2.14和2.18倍,分别,而B2组增加了60.05%，80.24%和1倍，分别。此外,外源邻苯二甲酸二异辛酯和邻苯二甲酸二丁酯被证明可以促进生长参数(藤蔓长度，阀杆直径,鲜重和干重)和抗氧化酶系统活性(SOD，连续种植西瓜的POD和CAT）。
结论：接种AMF后，菌根西瓜枯萎病发病率较低，与西瓜邻苯二甲酸酯分泌有关。外源邻苯二甲酸二异辛酯和邻苯二甲酸二丁酯能缓解西瓜连作障碍,减少枯萎病的发病率，并通过增加根际土壤中的酶活性和有益菌比例来促进西瓜的生长。此外,低浓度的邻苯二甲酸二异辛酯和高浓度的邻苯二甲酸二异辛酯效果最好。因此,土壤中一定浓度的邻苯二甲酸盐有助于缓解连作障碍。
