豌豆根腐病研究进展

根腐病是豌豆根部的重要病害之一,在世界各地豌豆产区均有发生,是制约豌豆产业持续健康发展的因素之一。世界上尚未发现对根腐病完全免疫的豌豆品种,防治方法主要以农业防治和化学防治为主。本文从豌豆根腐病的发生与分布、病原菌的分类及特点、抗性鉴定及评价标准、种质资源、分子标记及防治策略等方面对国内外豌豆根腐病研究现状进行综述。并提出抗病育种和未来豌豆根腐病综合防治的研究方向。     

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.     

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.     

新疆西梅栽培研究进展

西梅的果实是一种具有较高经济价值的储藏器官。新疆是西梅的主要产区之一,为使西梅的果实能具有较高的品质和产量,在适宜砧木的选择、优良品种的搭配、建园模式、高效栽培树形、土肥水管理和病虫害防治等方法和技术上都要有较高的要求。文章综述目前西梅的研究,结合新疆生产现状总结出提高西梅果实品质和产量的一系列方法和措施。     

种衣剂对防治雪梨瓜根腐病的药效研究

本文通过室内试验评估种衣剂对雪梨瓜种子发芽及苗期生长发育的安全性,并通过田间试验,比较种衣剂在不同时期对病情指数、防治效果及产量的影响,以筛选出对雪梨瓜根腐病防治效果理想的种衣剂。结果表明,4种种衣剂对雪梨瓜生长发育均安全。25%噻虫·咯·霜灵、12%甲·嘧·甲霜灵药后20 d防治效果达60%以上,62.5 g/L精甲·咯菌腈药后20 d的防效在50%以上;25%噻虫·咯·霜灵的稳定性好于12%甲·嘧·甲霜灵;35%多·福·克前期防治效果好,但持效性差。4种种衣剂对雪梨瓜都有一定的增产效果,25%噻虫·咯·霜灵增产23.30%,35%多·福·克增产17.96%。种衣剂处理能够有效防治雪梨瓜根腐病,在生产上建议首选25%噻虫·咯·霜灵作为雪梨瓜种衣剂,12%甲·嘧·甲霜灵和62.5 g/L精甲·咯菌腈可作为备选药剂交替使用。     

SiO2纳米颗粒对黄瓜“新唐山秋瓜”幼苗根系 解剖结构和气体交换的影响

硅是地壳内含量第二丰富的元素。近年来,人们开始探索硅的纳米材料在农业领域的运用。为更好地将二氧化硅纳米颗粒应用于园艺植物生产,以黄瓜栽培品种新唐山秋瓜(Cucumissativuscv."QiuguaofNew Tangshan")为材料,采用盆栽的方式研究不同施入量下(0、5、10和20m L)浓度为30%的二氧化硅溶液对黄瓜根系解剖结构、根毛形成、黄瓜叶片光合色素含量、叶绿素荧光参数以及气体交换的影响。结果表明,二氧化硅纳米颗粒对黄瓜的根系解剖结构并没有显著的影响,但对根毛形成的影响较大,在每盆20m L二氧化硅溶液条件下的根毛密度最高。施入不同量的二氧化硅溶液对黄瓜叶片光合色素含量均有提高但并不明显,且在较低施入浓度下,光合作用机制得到一定的提高。黄瓜叶片的净光合速率随着二氧化硅施入量的增加逐渐增加,但施入量对蒸腾速率的影响不明显。综上,二氧化硅纳米颗粒通过促进根毛形成以及提高净光合速率能够提高植物的生长机理,进而促进植物生长和产量的提高,将其运用于农业生产及园艺作物生产上具有广阔前景。     

Root architecture of sorghum genotypes differing in root angles under different water regimes

Plant root architecture offers the potential for increasing soil water accessibility, particularly under water-limited conditions. The objectives of this study were to evaluate the root architecture in two genotypes of sorghum (Sorghum bicolor (L.) Moench) differing in root angles and to assess the influence of different deficit irrigation regimes on root architecture. The response of two sorghum genotypes, ‘Early Hegari-Sart’ (EH; steep root angle) and ‘Bk7’ (shallow root angle) to four irrigation treatments was investigated in two replicated outdoor studies using large pots. The results indicated that EH possessed steeper brace and crown root angles, fewer brace roots, greater root biomass, and root length density than Bk7 at deeper soil depths (i.e., 15–30 and 30–45 cm) compared with a shallower depth (i.e., 0–15 cm). Across the soil profile, EH had greater root length density and length of roots of small diameter (<1 mm) than Bk7. Accordingly, EH showed more rapid soil-water capture than Bk7. Different levels of irrigation input greatly affected root architecture. Severe deficit irrigation (25% of full crop transpiration throughout the season) increased the angle and number of crown roots, root biomass, and root length density compared with 75 and 100% of full crop transpiration treatments. Consequently, root system architecture can be effectively manipulated through both genotypic selection and irrigation management to ensure optimal performance under different levels of soil available water.     

Analysis of residuals for stability assessment of rice genotypes

The analysis of residuals computes general adaptabilities (GAs) and specific adaptabilities (SAs) of genotypes similar to combining ability analysis. The residual analysis is simple and robust being based on the first-degree statistics, and is assumption-free. A unique statistic of ratio of variances (VR) of residuals for individual genotypes allows comparing their stability. The residuals analysis of genotype × environment (GE) interactions was performed for grain yield (t ha^?1) of 25 rice (Oryza sativa L.) genotypes, including two developed by marker-assisted selection for root traits quantitative trait loci (QTL), tested across 16 sites. Results were compared with the linear regression analysis for (i) full set of 16 sites showing adequacy of linear model and (ii) subset of nine-poor sites showing inadequacy of linear model. There was agreement between the two analyses for situation (i) but not for situation (ii) when the regression analysis fails because of nonlinearity but the residual analysis retains its validity.     

草莓丝核菌根腐病病原菌鉴定及7种杀菌剂的抑菌作用测定

为了解草莓丝核菌根腐病的病原种类及筛选防治丝核菌根腐病的有效杀菌剂,本研究基于形态学特征、细胞核荧光染色、菌丝融合群测定以及rDNA-ITS的序列分析,对北京和河北承德地区的草莓丝核菌根腐病的病原菌进行了鉴定,并利用菌丝生长速率法测定了7种杀菌剂对丝核菌的抑菌作用。结果发现,北京地区的丝核菌为双核丝核菌(binucleate Rhizoctonia,BNR),属于融合群AG-A;河北的丝核菌为立枯丝核菌Rhizoctonia solani,属于融合群AG-4。氟啶胺、吡唑醚菌酯、噻呋酰胺、戊唑醇、咯菌腈、氟硅唑对2种丝核菌均有很强的抑制作用,EC_(50)值为0.063 9～2.485 7μg/mL,抑霉唑的抑制作用较差,EC_(50)值为9.966 8～11.236 8μg/mL。同一种杀菌剂对不同丝核菌的抑制作用存在差异,噻呋酰胺、戊唑醇、氟硅唑、咯菌腈和抑霉唑对立枯丝核菌的抑制作用强于对双核丝核菌。试验结果为生产上合理选用杀菌剂防治草莓丝核菌根腐病提供了科学依据。