6-磷酸-海藻糖对普通菜豆籽粒产量和镰孢菌枯萎病抗性的影响

Effect of 6-Phosphate-Trehalose on Grain Yield and Fusarium wilt Resistance in Common Beans

6-磷酸-海藻糖是调控植物生长发育和响应胁迫的重要信号分子。为研究6-磷酸-海藻糖调控普通菜豆生长发育和抗病反应的功能,采用外源6-磷酸-海藻糖溶液喷施方法,揭示其对普通菜豆籽粒产量和镰孢菌枯萎病抗性的影响。结果表明,龙饭豆1号和红芸豆的百粒质量分别达到42.7 g和43.2 g,分别比对照(蒸馏水)提高18.6%和20.7%,产量可达2250.5 kg/hm^(2)和2549.6 kg/hm^(2),分别提高14.5%和19.2%。6-磷酸-海藻糖处理后,普通菜豆叶片可溶性糖类含量显著提升,红芸豆海藻糖、葡萄糖、蔗糖和淀粉水平最高,分别达37.4 nmol/g、4.3μmol/g、5.5μmol/g、3.6μmol/g;龙饭豆1号果糖含量最高,达到8.4μmol/g。龙饭豆1号叶片净光合速率、胞间CO_(2)浓度和蒸腾速率最高,分别达到18.6、249.6、6.5μmol/(m^(2)·s),红芸豆气孔导度最大,达0.57μmol/(m^(2)·s)。外源6-磷酸-海藻糖的喷施促进了植株生长发育和碳水化合物的合成,同时显著提高叶片光合效率,促进营养物质向籽粒转运。此外,接菌48 h后,6-磷酸-海藻糖处理的菜豆根中防御因子活性或含量达到最高,过氧化物酶活性、超氧化物歧化酶活性和苯丙氨酸解氨酶活性分别达到78.3、32.9、0.054 nk at/mg,H_(2)O_(2)含量达到0.33 ng/mg。PR1、PR2、PR5基因的相对表达量达到最高,分别为接种0 h基因表达量的8.3、13.2、9.4倍。接菌28 d后植株发病级别显著低于对照,仅为4.2。综上,6-磷酸-海藻糖可能通过调节可溶性糖含量、叶片光合效率促进产量提升,通过诱导植物防御因子的表达激活寄主抗病性。

6-phosphate-trehalose is an important signaling molecule that regulates the plant growth and development,and responds to the stress.To study its function in regulating growth,development and resistance-related reaction,the spraying of exogenous 6-phosphate-trehalose solution was used to reveal the effect of 6-phosphate-trehalose on the grain yield and Fusarium wilt resistance.The results of this study showed that exogenous T6P praying could significantly improve the relevant grain yield traits.The 100-grain weights of Longfandou No.1 and Red kidney bean reached 42.7 g and 43.2 g,increased by 18.6%and 20.7%,respectively,and the yields were 2250.5 kg/ha and 2549.6 kg/ha,increased by 14.5%and 19.2%.After treatment by 6-phosphate-trehalose,the content of soluble carbohydrates in leaves of common beans significantly increased,Red kidney bean had the highest levels of trehalose,glucose,sucrose and starch,respectively reaching 37.4 nmol/g,4.3μmol/g,5.5μmol/g,3.6μmol/g.Longfandou No.1 had the highest fructose content,reaching 8.4μmol/g;Longfandou No.1 had the highest net photosynthetic rate,intercellular CO_(2) concentration and transpiration rate,reaching 18.6,249.6,and 6.5μmol/(m^(2)·s),respectively.The stomatal conductance of Red kidney bean was maximum,reaching 0.57μmol/(m^(2)·s).Spraying of exogenous 6-phosphate-trehalose solution promoted plant growth,development and carbohydrate synthesis,improved the photosynthetic efficiency,and also promoted the transport of nutrients from leaves to grains.In addition,the activity or content of the defense factors in the bean roots treated with 6-phosphate-trehalose reached the highest level at 48 h after inoculation.T6P induced the significant increase in POD,SOD and PAL activities,reaching 78.3,32.9 and 0.054 nk at/mg,H_(2)O_(2) content was 0.33 ng/mg and the expression levels of defense genes PR1,PR2,and PR5 in the roots of common beans reached peak,which were 8.3,13.2 and 9.4 times of that at 0 h post inoculation,respectively.The disease score was only 4.2 after 28 days post inoculation.In conclusion,6-phosphate-trehalose probably increases the yield by regulating soluble sugar content and leaf photosynthetic efficiency,and activates host disease resistance through the expression of plant defense factors.