摘要
在大田条件下,以农大108为试验材料,采用透光率为50%的遮阴网,于苗期、穗期和花粒期3个时期分别全天遮阴处理24、28和48d,于处理后每隔10d测定一次淀粉合成关键酶的活性,并于成熟后测产。结果表明,遮阴显著降低玉米的生物产量和籽粒产量,苗期、穗期和花粒期遮阴处理单株生物产量分别较对照(自然光照)降低23.9%、31.4%和38.9%,籽粒产量分别降低24.6%、35.6%和68.2%。遮阴处理显著降低了籽粒淀粉合成关键酶的活性,叶片的磷酸蔗糖合成酶(SPS)和籽粒的蔗糖合成酶(SS)、可溶性淀粉合成酶(SSS)和淀粉粒结合淀粉合成酶(GBSS)、腺苷二磷酸葡萄糖焦磷酸化酶(ADPGPPase)、尿苷二磷酸葡萄糖焦磷酸化酶(UDPGPPase)活性都显著降低,但花粒期遮阴影响最显著,穗期其次,苗期遮阴影响相对较小。认为大田遮阴使玉米产量和淀粉含量降低,是由于光合下降,生物产量降低以及玉米淀粉合成关键酶活性降低,减少了光合产物向籽粒的运转和分配。
The shading experiment was conducted in the field in 2004-2005, using the maize cultivar ND108, to study the effects of shading at different stages on key enzymes involved in starch synthesis of maize, and provide theoretical evidence to improve yield and quality of summer maize. The field was shaded by shading nets which prevented 50% sunlight. The heights of the nets were raised with the growth of maize plant, and the distance between the nets and the top of maize plant remained about 2.5 m. Only the illumination condition was changed after shading, while the aeration condition and relative humidity were not changed. Other environmental factor changes were due to the change of illumination intensity. The treatments were designed at seedling to jointing, jointing to flowering, and flowering to maturity stages, with 24, 28, and 48 days shading respectively. The activities of SPS （sucrose-phosphate synthase）, SS （sucrose synthase）, SSS （soluble starch synthase）, GBSS （granule-bound-starch synthase）, ADPGPPase （adenosine diphosphorate glucose pyrphorylase）, and UDPGPPase （uridine diphosphorate glucose pyrophorylase） were determined every 10 days after shading, and kernel yield was measured after maturity stage. The results showed that the biomass and kernel yield of ND108 decreased significantly after shading. Compared with the control （nature sunlight without shading）, the biomass of ND108 decreased by 23.9%, 31.4%, and 38.9% from seedling to jointing, jointing to flowering, and flowering to maturity stages, respectively, while the kernel yield decreased by 24.6%, 35.6%, and 68.2%, respectively. Leaf SPS activity and kernel SS, GBSS, SSS, ADPGPPase, and UDPGPPase activities of maize decreased significantly after shading, and different shading phases had different effects with the sequence of flowering to maturity 〉 joining to flowering 〉 seedling to joining. The results suggested that the main causes of grain yield and starch content decreasing after shaded were the decreasing of bo
出处
《作物学报》
CAS
CSCD
北大核心
2008年第8期1470-1474,共5页
Acta Agronomica Sinica
基金
山东省自然科学基金项目(Q2006D03)
国家科技支撑计划项目(2007BAD31B04
2006BAD02A09)
中国博士后科学基金项目(20070410368)
公益性行业(农业)科研专项(nyhyzx07-003)
山东省优秀中青年科学家科研奖励基金(2007BS06003)
关键词
夏玉米
遮阴
淀粉
淀粉合成酶
Summer maize（Zey mays L.）
Shading
Starch
Starch synthesis enzymes
