不同基质及生根剂浓度对五种园林植物扦插生根的影响

以5种园林植物为材料,进行不同基质与不同生根剂浓度对植物扦插生根的比较研究.结果表明:月季、大叶黄杨最适宜的基质是河沙,小叶女贞、八角金盘最适宜的基质是珍珠岩,鹅掌柴最适宜的基质是混合基质.月季、大叶黄杨最合适的生根剂浓度为3 000 mg/kg,小叶女贞最合适的生根剂浓度为5000mg/kg,八角金盘、鹅掌柴最合适的生根剂浓度为1000mg/kg.     

甜菜产生叉根的原因初探

从种子芽势、作物茬口、播种量、镇压次数、育苗苗龄方面调查分析了甜菜产生叉根的原因。     

Mineral content of three olive cultivars irrigated with treated industrial wastewater

The reuse of saline treated industrial wastewater generated by textile firms mixed with municipal domestic effluent for irrigation was used to asses its effect on the mineral content of three olive (Olea europaea L.) cultivars under greenhouse and field conditions during two complete vegetative cycles. Chemical analysis of the treated wastewater indicated that the element concentrations fall within the permissible range of irrigation water used for plants. However, little impermissible accumulation of Na and Mg higher than the recommended maximum concentration was observed. Irrigation water with six electrical conductivities (EC = 0.78, 1.0, 2.0, 3.0, 4.0 and 5.0 dS m⁻¹ in treatments T₀, T₁, T₂, T₃, T₄, T₅, respectively) were compared in the greenhouse experiment. The olive trees in the field experiment were trickle irrigated with potable water and treated wastewater (average EC = 4.2 dS m⁻¹). The results of the greenhouse experiment showed that leaf N, Cu, Mn, Fe, Pb, and Na contents increased with increasing salinity of the treated wastewater. This increase was accompanied with a decrease in K and Mg contents. Leaf Ca and Cl concentrations were not considerably affected. Ion analysis in roots indicated that the contents of P, Na, Cl, Mn, and Pb increased while K decreased as treated wastewater salinity increased. Consequently, in most cases T₄ and T₅ gave a highly significant increase or decrease in accumulation of the previously mentioned minerals. A considerable variation in the studied cultivars was noticed. ‘Nabali’ was considered the most tolerant cultivar for the high salinity levels of the treated wastewater; its transporting selectivity of Na from root to leaf was higher and more Na was retained in the roots. Tissue analysis of leaves indicated that the element concentrations were within the adequate levels except those of Fe in ‘Nabali’ and ‘Manzanillo’, Na in ‘Improved Nabali’ and Cu in ‘Nabali’ and ‘Manzanillo’. In view of these findings, the negligible accumulation of minerals in leaves and roots indicated that this kind of textile effluent can be used as a valid alternative for irrigation of olive orchards with continuous monitoring of mineral levels.     

不同灌溉和施肥方式对杂交稻生长和根际环境的影响

对杂交稻中优218不同灌溉方式和氮肥管理下水稻生长和根际环境的变化进行研究,结果表明,水稻好气灌溉条件下各施肥处理产量均高于传统灌溉处理,产量比淹水灌溉增产10.5%~11.3%,主要表现在每穗粒数增加而提高产量。好气灌溉与淹水灌溉比较各生育期地上部干物重和叶面积指数均增加,土壤氧化还原电位提高,放线菌数量显著增加。增加有机肥降低土壤氧化还原电位和提高放线菌数量,在好气灌溉条件下施相同氮素有机肥放线菌数多于化肥。     

防治胡椒瘟病生物农药筛选及其盆栽药效试验

胡椒瘟病是危害中国胡椒产业的首要病害,目前主要依赖使用化学农药防治,筛选应用生物农药是减少化学农药用量的有效途径。本文通过室内毒力测定和室外盆栽药效试验,测定了5种生物农药对胡椒瘟病的防治效果。结果表明:室内毒力测定木霉菌WP、枯草芽孢杆菌WP和Z菌株发酵液对胡椒瘟病病原菌的抑菌效果好且敏感性高,EC50分别为0.49、0.78、1.13μg/m L;盆栽药效试验Z菌株发酵液和枯草芽孢杆菌WP对胡椒瘟病防效最好,平均防效分别为83%和82%,芽孢杆菌/淡紫拟青霉WP的防效次之,平均防效为69%。综合来看,Z菌株发酵液和枯草芽孢杆菌WP对胡椒瘟病具有很好防效,具备良好的绿色防控潜力。     

田间条件下水稻根系分布及其与土壤容重的关系

 采用大田和筒栽方法研究了超高产三系杂交稻协优9308和两系杂交稻两优培九在穗分化期和开花期根系生长和分布及土壤容重对根系分布的影响。结果表明，在田间条件下，土层15 cm内水稻根系占根系总量的89%～98%，深层根系丛间比丛中比例高。不早衰的协优9308根系生长量较两优培九大。土壤容重提高，根系总生长量下降，且深层根系的量和比例下降。就深耕法对水稻根系生长和分布的影响进行了讨论。     

大豆疫霉菌生物学性状的遗传与变异

大豆疫霉菌引起的大豆疫病是大豆上危害严重的毁灭性病害之一.采用经典遗传学方法研究大豆疫霉菌单孢后代的菌丝生长速率、菌落形态、产孢量以及同宗配合性状的遗传变异,以期为有效控制大豆疫病的发展和蔓延奠定基础.结果表明,菌落形态、生长速率和同宗配合性状在单孢后代可稳定遗传,控制上述性状的遗传因子是纯合的;大豆疫霉菌的游动孢子产生能力在单孢后代发生连续性变异,表明这种性状可能是数量遗传性状,也可能控制这种性状的基因为杂合基因或细胞质遗传因子.研究结果初步揭示了大豆疫霉的遗传特征、遗传多样性及多样性产生的遗传学基础.     

马铃薯贮藏期腐烂原因及防治对策

马铃薯是一种高产作物,收后贮藏、稳定价格、均衡上市是提高农民收入的主要途径之一。贮藏过程中有效的控制腐烂率,更加显得重要。笔者根据定西市马铃薯生产贮藏实际情况,结合马铃薯作物的贮藏特点,提供具体的操作、管理措施,供当地马铃薯贮藏参考。     

南瓜根系及根部土壤水浸液化感作用研究

以黄瓜、西瓜作受体材料,研究南瓜根系及根部土壤水浸液的化感作用。结果表明,南瓜根系及根部土壤水浸液对受体种子萌发率、萌发指数、幼苗根长、苗高和苗干重存在化感促进或抑制效应。对指标进行综合效应分析,发现南瓜根系及根部土壤水浸液化感作用呈现浓度效应及受体差异性,一定浓度水浸液处理对受体种子萌发阶段、幼苗生长阶段及整体生长有促进作用,但西瓜较黄瓜对浓度敏感,0.02 g/mL南瓜根系及根部土壤水浸液对黄瓜化感促进强度最大,0.04 g/mL处理下,表现为化感促进强度降低或微弱抑制作用;0.02和0.04 g/mL南瓜根系水浸液及0.04 g/mL根部土壤水浸液对西瓜则表现为强烈抑制现象。     

4种悬钩子属植物的繁育方式研究

选取山莓(Rubus corchorifolius L.f.)、插田泡(R.coreanus Miq.)、光滑悬钩子(R.tsangii Merr.)、茅莓(R.parvifolius L.)4种野生悬钩子健壮植株为材料,通过扦插、分株和根蘖、压条等试验,研究其最适繁育方式。结果表明,4种悬钩子的木质化结构不充分,扦插生根较为困难;山莓可通过分株和根蘖的方式繁殖;插田泡可通过分株、根蘖、压条的方式进行繁殖;光滑悬钩子主要通过分株和根蘖的方式繁殖;茅莓可通过分株、根蘖和压条的方式繁殖。