光周期对糜子生长发育及叶片内源激素的调控效应

Regulation Effects of Photoperiod on Growth and Leaf Endogenous Hormones in Broomcorn Millet

【目的】明确光周期对糜子生理生态指标的影响,为糜子光周期遗传调控网络及相关基因定位奠定基础。【方法】通过盆栽试验设置4种光周期处理,选用光敏感性差异不同的3个品种(N1-光钝感-内糜1号,N2-光中间-内糜2号,N3-光敏感-宁糜14号),调查不同处理植株的物候期,测定不同处理抽穗期内源激素含量、成熟期株高、籽粒蛋白质含量和光钝感品种抽穗后的净光合速率。【结果】长日照显著延长糜子生育期,增加株高,光敏感品种N3全生育期长日照生育期天数和株高较短日照分别增加62.07%、104.24%,光钝感品种N1为3.51%、33.35%;随着生育进程的推进,抽穗后叶片净光合速率表现出明显差异,延长光照能显著增强糜子叶片净光合速率,增加干物质积累;光周期处理下不同光敏感品种内源激素变化明显,一定浓度IAA促进抽穗,IAA与GA和ZR呈极显著正相关,相关系数分别为0.51和0.40,与ABA呈极显著负相关(-0.62),ABA与GA和ZR呈极显著负相关,分别为-0.70和-0.39,GA与ZR呈极显著正相关(0.47);全生育期短日照条件下不同光敏感品种籽粒蛋白质含量显著高于其他处理,全生育期短日照N1-2、N2-2、N3-2蛋白质含量较全生育期长日照N1-4、N2-4、N3-4分别高18.89%、80.50%和61.23%。光敏感品种较光钝感品种的籽粒蛋白质含量更容易受短日照影响。【结论】光周期显著影响不同光敏感性糜子生长发育及内源激素含量,长日照显著延长糜子生育期、增加植株株高和增强叶片净光合速率,但降低籽粒蛋白质含量,一定浓度IAA含量调控糜子由营养生长向生殖生长转变。

【Objective】In this study,the variation law of photoperiod on physiology and ecology index of broomcorn millet were observed,which would facilitate to develop the genetic regulation network and map related genes of photoperiod.【Method】The experiments were conducted using 3 broomcorn millet varieties(N1-light insensitive-Neimi 1,N2-light middle-Neimi 2,and N3-light sensitive-Ningmi 14)with different light insensitive degree and with four photoperiod treatments in the pot.The phenological period was investigated.The endogenous hormone content at heading stage,plant height and grain protein content at mature period,and net photosynthetic rate of light insensitive variety after heading were measured.【Result】The growth period and plant height of broomcorn millet were significantly increase by long day compared with short day,which in light sensitive material N3 was 62.07%and 104.24%higher than that of short day,and light insensitive material N1 was 3.51%and 33.35%,respectively.The net photosynthetic rate of leaves after heading showed a significant difference with the development of the growth process,the net photosynthetic rate increased significantly with the prolonged light for accumulating more dry matter.Different photosensitive materials had different regulating mechanisms of endogenous hormones under different photoperiod treatments.The accumulation of IAA content to a certain concentration could promote the plant heading.IAA was significantly positively correlated with GA and ZR,with correlation coefficients of 0.51 and 0.40,respectively,while it was significantly negatively correlated with ABA,with the value of-0.62.The ABA content was negatively correlated with GA and ZR,with the value of-0.70 and-0.39,respectively,and the GA content was positively correlated with ZR,with the values of 0.47.The grain protein content of different light-sensitive materials under the short day in the whole growth period was significantly higher than that of other treatments.The grain protein content of N1,N2 and N3 under short day in the whole growth period were 18.89%,80.50%and 61.23%higher than those of long day in the whole growth period,respectively,indicating that the light-sensitive material was more susceptible to short-day sunshine than the light-insensitive material.【Conclusion】The photoperiod significantly affected the growth and endogenous hormone content in different photosensitivity materials.Long day significantly prolonged the growth period,increased plant height and enhanced leaf net photosynthetic rate,but decreased the grain protein content in broomcorn millet.IAA content to a certain concentration could promote the transformation of broomcorn millet from vegetative to reproductive growth.