hrpZ_(Psta)在转基因大豆中定量表达与疫霉根腐病和灰斑病抗性相关研究

以T5转hrpZPsta基因大豆JN29-705-15和JL30-187为材料,利用实时荧光定量PCR技术(Quantitative Real Time PCR,qRT-PCR)检测了目标基因在转基因大豆不同组织中的表达量,分别利用下胚轴侵染法和叶面喷施法鉴定疫霉根腐病抗性和灰斑病抗性,并分析目的基因表达量与疫霉根腐病和灰斑病抗性的相关性。结果表明:hrpZPsta基因在大豆的叶、茎、根、籽粒中均有表达,二个株系平均相对表达量分别为8.2/6.1、0.9/0.7、6.5/4.6和0.8/0.7;T5转hrpZPsta基因大豆抗疫霉根腐病和灰斑病能力与野生型相比均有所提高,JN29-705-15对疫霉根腐病抗性从感病提高到中抗,而JL30-187从中抗提高到抗病;hrpZPsta基因在叶中的表达量也与抗灰斑病能力呈正相关,与病情级别呈极显著负相关。试验结果初步证明了外源基因hrp ZPsta在大豆植株中的表达量与受体植株对疫霉根腐病和灰斑病抗性存在一定的相关性。     

Root zone temperature alters storage root formation and growth of sweetpotato

Large mounds amended with plant residues are a common cultivation method for sweetpotato (Ipomoea batatas) in the western parts of the Papua New Guinea highlands, with a suggested benefit of elevated root zone temperature (RZT) from decomposition. This study aimed to evaluate whether RZT affects the formation and growth of sweetpotato storage roots. Experiments evaluated the effects of a constant elevated RZT on the Beauregard cultivar and of a short‐term increase in RZT on the Beauregard and Northern Star cultivars. Plants were grown in 18‐L pots divided into a control compartment (constant RZT at 20°C) and a treated compartment (RZT at 30, 40 or 50°C). Constant elevated RZT was maintained until harvest, while short‐term increase in RZT occurred in weeks 2 and 3 only. Constant elevated RZT did not affect the total number of storage roots, but RZT of 30°C and above reduced the dry‐biomass of storage roots. The short‐term increase in RZT did not alter the total number or dry‐biomass of storage roots in Beauregard, while both of these attributes were reduced at RZT of 40°C or above in Northern Star. Elevated RZT inhibited dry‐biomass accumulation of storage root, with a more pronounced impact at constant elevated RZT. These results demonstrate that any benefits of the mound culture on sweetpotato yield production do not arise through the influence of temperature elevation.     

防洪堤施工中筑堤粗粒土控制干密度的合理性分析

文章对相对密度控制问题进行分析,并提出几点建议。     

栽培密度对吉杂141群体生理指标及产量的影响

[目的]明确矮秆早熟高粱品种吉杂141在佳木斯地区的合理栽培密度。[方法]以吉杂141为研究对象,在大田生产试验条件下,采用平播的方式,设置15万、20万、25万、30万、35万株/hm2共5个栽培密度,研究不同栽培密度下,吉杂141的群体生理指标、产量及产量性状。[结果]随着栽培密度的增大,叶面积指数增加,叶绿素含量下降,群体光合势和总光合势增加,株高差异不显著,穗长、穗粗逐渐下降,生物产量上升,千粒重和单穗重下降。[结论]初步明确在佳木斯地区采用平播方式吉杂141最适栽培密度为20万株/hm2,产量可达9 203.36 kg/hm2。     

不同用量松土促根剂对冬小麦产量的影响

研究了Agri-Star松土促根剂在冬小麦上的合理用量,为该产品大面积推广提供依据.结果表明,在正常旋耕施肥(配方肥750 kg/hm2+旋耕12 cm,CK2)的基础上,获得最高产量的松土促根剂施用量为18.13 kg/hm2,最佳经济施用量为16.87 kg/hm2,施用松土促根剂13.5 kg/hm2处理较CK2平均增产26.18％.施Agri-Star松土促根剂是小麦生产上值得推广的新技术.     

春花生超高产栽培技术模式研究与应用

采取正交旋转回归设计,以播种期、种植密度、施肥量为试验因子,以9000kg/hm2为产量目标函数,进行春花生超高产栽培模式集成研究。结果表明,在鲁西南平原地区,超高产春花生以种植密度和N、P、K施肥量为主要限制因素,播种期为次要限制因素。明确了春花生单产达到9000kg/hm2以上的最佳种植密度、播种期和合理的N、P2O5、K2O施用量为主要指标的栽培技术模式,增产效果显著。     

增密减氮对弱筋小麦‘宁麦13’产量和品质的影响

为实现弱筋小麦优质稳产,解决当前弱筋小麦存在品质稳定性差的问题。本试验以弱筋小麦‘宁麦13’为试材,结合方差分析等方法研究增密减氮对弱筋小麦的产量、群体质量指标以及籽粒品质的影响。结果表明,在240 kg/hm²施氮水平条件下,随着密度的增加,小麦LAI、干物质积累量均呈先增加后下降的趋势,密度超过240×10⁴/hm²会导致LAI、干物质积累量、产量下降。在240×10⁴/hm²密度条件下,施氮量超过240 kg/hm²会导致小麦叶面积指数、SPAD值、花后干物质积累量和产量下降。适当的增密减氮有利于提高弱筋小麦的优质稳产,而过量增密减氮则会导致小麦产量下降,品质不稳定。为实现产量和品质的最优化,生产上推荐采用种植密度为240×10⁴/hm²,施氮量为180 kg/hm²,氮肥运筹为7:1:2:0的栽培模式。     

肉毒毒素重组抗原表达系统研究进展

肉毒中毒是肉毒杆菌引起的一种致死性的神经麻痹性疾病,应对内毒中毒的最有效方法是预防或疫苗接种,肉毒毒素Hc段是研制亚单位疫苗的首选.通过基因重组技术能够将肉毒毒素Hc片段在大肠杆菌或酵母表达系统中进行大规模表达.阐述了这2种表达载体在肉毒毒素亚单位疫苗的研制及发酵生产情况.     

中国农业面源污染排放的空间差异及其动态演变

以2003—2014年为研究时段,在测算农业面源污染排放强度的基础上,综合运用基尼系数和非参数估计方法,研究我国农业面源污染的空间差异及其动态演变,结果表明:1)我国农业面源污染排放总体下降,且表现出明显的空间差异,东部和中部地区的排放强度较高,西部和东北地区则相对较低。2)2003—2014年,中国农业面源污染排放强度的区域差异略微扩大,地区间差异是其总体差异的主要来源。3)核密度估计结果表明,中国农业面源污染排放总体差异表现为"下降-上升-下降"的波动变化趋势。4)马尔科夫链分析表明,中国农业面源污染在不同类型间的相互流动较为微弱,但从长期来看,存在向两极分化发展的趋势特征。     

The priority of management factors for reducing the yield gap of summer maize in the north of Huang-Huai-Hai region,China

Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity(CK), farmer practice(FP), high yield and high efficiency(HH), and super high yield(SH), to estimate the yield gap. Different factorial experiments(fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha~(–1), respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors(contribution rates) were plant density(13.29%)fertilizer(11.95%)hybrids(8.19%)irrigation(4%) for FP to HH, and hybrids(8.94%)plant density(4.84%)fertilizer(1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH.