夏玉米主要穗部性状结构分析和高产育种探索

利用17个玉米杂交种通过对7个穗部性状与产量进行相关和通径分析,结果表明:结实长、出籽率、穗长、行粒数、穗行数、千粒重与产量的相关系数均为正值且较大;出籽率、结实长、千粒重、穗粗、穗长对产量的直接通径系数也为正值且较大.因此,对产量影响较大的因素有出籽率、结实长和千粒重,提高出籽率和千粒重,增加结实长兼顾其它穗部性状是玉米高产的有效途径。     

玉米主要农艺性状的相关通径分析

用不完全双列杂交法组配25个杂交组合,对玉米的穗长等7个农艺性状与子粒产量进行遗传相关和通径分析.结果表明,穗长等7个农艺性状与子粒产量的遗传相关系数除穗行数外,其余为正值.其中穗长、行粒数、结实长达到极显著标准.通径分析结果表明:穗长、穗粗、出籽率与子粒产量的直接通径系数为正值.其中穗长对产量的直接通径系数最大(p=8.760 4),其次为穗粗(p=7.201 7),而千粒重等4个性状的直接通径系数为负值.选育高产玉米杂交种时,应高度重视选择果穗长而粗、出籽率高的类型。     

玉米杂交种主要农艺性状的相关和通径分析

用不完全双列杂交法组配25个组合，对玉米的生育期等10个农艺性状与籽粒产量的遗传相关和通径进行研究。结果表明，除生育期外的9个农艺性状与籽粒产量的遗传相关系数为正值，且达到显著或极显著差异。结实长、穗粗、株高、出籽率、百粒重、穗长和穗行数与籽粒产量的直接效应为正值，其中结实长与产量的直接通径系数最大(P＝0．4676)，其次为穗粗(P＝0.4170)，而生育期等3个性状的直接通径系数为负值。选育玉米高产杂交种时，要注重果穗结实长度和穗粗的选择。     

玉米11个农艺性状的通径分析

用不完全双列杂交法组配成35个组合，对玉米的生育期等11个性状与籽粒产量的遗传相关和通径进行了研究。结果表明，株高等7个性状与籽粒产量呈极显著正相关，生育期为显著正相关，穗位高和穗粗为正相关，但差异不显著，穗行数为显著负相关。通径分析结果表明：果穗结实长度等7个性状与籽粒产量的直接通径系数为正值，面千粒重等4个性状的直接通径系数为负值。在玉米高产育种中，要重视选择果穗结实长、籽粒行数多、果穗长和出籽率高的类型，适当注意穗位高等3个性状的选择，对千粒重等4个性状的选择可适当放宽。同时，也要注意到各性状间的相关性，把杂交种的各农艺性状协调到最佳程度。     

玉米杂交种的产量比较及主要农艺性状的相关和通径分析

本试验选用本所选育和引进的17个玉米杂交种为供试材料，采用随机区组设计。通过对各杂交种的产量、生育期和综合农艺性状的分析，选出了高产、优质、抗逆性强、生育期适中的杂交种CX-711、中单9409、CX-649、CX-712、CX-777、CX751等。经过对产量、千粒重、出籽率。穗长、穗粗等11个农艺性状进行相关分析和通径分析表明，对产量影响最大的因素是千粒重(r=0.5411^*)，相关系数达显著水平。穗粗(r=0.4767)，出籽率(r=0.4067)和穗长(r=0.14)与产量的关系呈正相关。性状之间株高与穗位高和茎粗(r=0.8222^**，(r=0.7606^**)、穗长与行粒数(r=0.7065^**)之间呈极显著正相关。指出提高千粒重，增加穗粗和穗长，提高出籽率并兼顾其他农艺性状是提高玉米产量的有效途径。     

不同年代主要玉米品种穗部性状演变研究

采用裂区试验设计,以密度为主区(15 000、45 000、75 000株/hm2),品种为副区,对我国不同年代34个主要玉米品种穗部性状演变进行了研究。结果表明:随着年代的更替,产量、穗长、穗粗、穗行数、行粒数、秃尖长、千粒重显著增加,出籽率显著降低。通径分析结果表明:主要穗部性状对产量的作用依次为穗粗千粒重行粒数出籽率,穗粗、千粒重、行粒数的增加是玉米产量提高的主要原因。在玉米品种选育中应保持行粒数,着重改良穗粗、千粒重,提高出籽率,并协调出籽率与其他性状的关系。     

玉米产量与其它农艺性状的灰色关联度分析

应用灰色关联度分析方法，对玉米变量与其它农艺性状关系的密切程度进行了分析。结果表明，产量与９个性状的关联顺序依次为生育期〉千粒重〉穗长〉穗行数〉穗粒高〉出籽率〉株高〉行粒数〉秃尖。与产量关系密切的性状是生育期、千粒重、穗长、穗行数、穗位高和出籽率。     

玉米8个产量构成因素的通径分析

组配成不完全双列杂交的90个组合用3次重复的随机区组设计对玉米穗长等8个产量组成因素与子粒产量的关系进行了遗传相关和通径分析.结果表明穗长等8个性状与子粒产量的遗传相关系数均为正值.其中,结实性与子粒产量的遗传相关系数未达0.05的显著水平,千粒重与子粒产量的遗传相关系数达到0.05的显著水平,其余6个性状与子粒产量的遗传相关系数均达到了0.01的显著水平.通径分析结果表明,8个产量组成性状对子粒产量的相对重要性依次为结实长>穗粗>出籽率>千粒重>行粒数>穗行数>结实性>穗长.选育夏播高产杂交种时,要重视选择果穗结实长、果穗粗、出籽率高的类型。     

黑龙江省西部干旱地区玉米穗部性状与产量关系的分析

以15个杂交组合为试验材料．通过穗部7个性状与小区产量进行相关及通径分析．对玉米产量与穗部性状的关系进行研究。结果表明：结实长、出子率、穗长、行粒数、穗行数、百粒重与产量的相关系数均较大：出子率、结实长、百粒重、穗长对产量的直接通径系数也较大。由此可知．对产量影响较大的因素有出子率、结实长和百粒重,提高出子率和百粒重,增加结实长．并兼顾其他穗部性状是提高玉米产量的有效途径。     

夏玉米杂交种产量性状与产量的通径分析

选用30个玉米杂交种为供试材料,采用随机区组设计。经过对产量、穗长、行粒数、穗行数、千粒重等6个农艺性状进行相关分析和通径分析表明,对产量影响最大的因素是行粒数(r=0.5366),相关系数达显著水平。穗长(r=0.4989)、千粒重(r=0.4512)与产量的关系呈正相关。提高行粒数和千粒重,增加穗长并兼顾其他农艺性状是提高玉米产量的有效途径。     

我国麻类标准现状与分析

介绍了我国麻类标准的现状。通过分析,指出了存在的问题,主要表现在标准体系不完善、标准更新不及时,协调性差及贯彻执行不力等。提出了我国麻类标准应采取的对策。     

水稻病虫害绿色防控与统防统治融合技术模式示范

2017—2018年,在同安镇粮食产能区示范推广水稻病虫害绿色防控与统防统治融合技术模式,取得了显著成效。融合技术示范区比常规区减少用药2~3次,用药量减少37.6%,防治成本降低400元/hm^2;水稻产量增加12.8%,收益增加2 835元/hm^2。     

Effects of Organic and Chemical Fertilizers and Arbuscular Mycorrhizal Inoculation on Growth and Quality of Cucumber and Lettuce

Summary

Arbuscular mycorrhizae were inoculated into phosphorus-deficient soil fertilized with either organic or chemical fertilizer with cucumber (Cucumis sativus L.) as the first crop and lettuce (Lactu-ca sativa L.) as the second crop but without additional fertilization and AM inoculation. AM increased dry matter and fruit yield of cucumber significantly in the unfertilized, organic-fertilized and P-deficient plants compared with the fully chemical-fertilized plants. AM inoculation increased the available phosphorus in plant and soil by around 30% for all treatments except for those chemically-fertilized. The rate of AM infection did not differ significantly among the fertilization treatments, but the infection intensity was higher in unfertilized, organic-fertilized and phosphorus-deficient treatments than chemical-fertilized treatment. The residual effects of AM-inoculated to cucumber were evident for lettuce in all pre-treatments that were unfertilized and un-inoculated for the second cropping. Without P-fertilization, neither crop could grow optimally even when the soil was inoculated with AM, suggesting that AM could not serve as a substitute for phosphorus fertilizer. However, the other beneficial effects of AM on crop growth and yield could not be fulfilled with phosphorus fertilizer.     

春季氮肥和多效唑调控对小麦生育和产量的影响

为明确春季调控措施对冬小麦生长发育和籽粒产量的影响,以冬小麦品种石新828为材料进行田间试验,4个处理分别为:起身期追全部氮肥(除基肥外,下同)并叶面喷多效唑(N1);起身期追2/3氮肥并喷多效唑+拔节期追1/3氮肥(N2);起身期追1/3氮肥+拔节期追2/3氮肥(N3);拔节期追全部氮肥(N4)。生育期间测定群体和个体生育特性,成熟期调查产量性状。结果表明,N1和N2处理小麦拔节期的总茎数、叶面积指数(LAI)和干物质积累量均显著高于N4和N3处理。孕穗期N4和N3处理小麦的总茎数、LAI和干物质积累量显著高于N1和N2处理。开花到成熟期各处理的总茎数、LAI和干物质积累量差异均不显著。孕穗期前,不同处理的株高差异不显著,孕穗期后,N4处理的株高最高,且显著高于N1处理。各处理基部节间直径和中上部节间长的差异不显著,N4处理基部第一节间长度显著大于其他处理。随追氮时期前移或前期施氮量增多,不孕小穗数减少,结实小穗和穗粒数增加,N1比N4处理不孕小穗数显著减少,结实小穗和穗粒数显著增多。N1处理小麦成熟期的千粒重最高,且显著高于N4处理。N1处理的籽粒产量最高,且显著高于N3和N4处理。起身期追氮配合多效唑调控,可以获得比拔节期追氮更高的穗粒数和千粒重,从而获得更高的产量。     

Preparation and characterization of fibers of waste and fresh polyethylene terephtalate and mixtures of them

Textile fibers were obtained from secondary polyethylene terephtalate (PET) and its mixtures with primary PET at initial orientation of 18000–33000 %, rate of additional orientation drawing 3.5–6.5 times and temperature of thermal fixation 363–413 K. The fibers’ tensile strength was found to decrease and elongation at break to increase with the decrease of their linear density under the conditions of fibers formation. For the fibers based on polymer mixtures, the presence of oxidized fragments in the secondary PET limited the compatibility of the two polymers which resulted in deteriorated tensile properties. The linear density (4–16 dtex), tensile strength (30–50 cN/tex) and elongation at break (20–60 %) of the PET fibers obtained were close to these for the industrially produced polymer fibers. The values of the average diameter of the fibers formed and oriented under laboratory conditions allows classifying them between the fine and the coarse textile fibers which makes them suitable for the textile industry.     

海南百香果病虫害种类调查鉴定及其发生危害

百香果是海南省的新兴产业,也是我国多个省区扶贫攻坚的重要产业。病虫害是影响百香果产业的重要因素,随着海南百香果种植面积越来越大,病虫害对百香果产业的不利影响越来越凸显。由于缺乏百香果病虫害种类调查鉴定的基础性研究,许多种植户对田间发生的病虫害种类识别不足,从而影响了百香果病虫害的防控效果。为了摸清海南百香果种植区的病虫害种类,于2019—2021年对海南省儋州市、乐东县、屯昌县、文昌市、三亚市、东方市、保亭县、白沙县、海口市等百香果种植区的病虫害进行了系统调查与鉴定,并对其发生危害特点进行了研究。鉴定发现海南百香果种植区的病害有11种,分别是病毒病、茎基腐病、炭疽病、疮痂病、疫病、灰霉病、果腐病、褐斑病、烟煤病、藻斑病和缺镁。重要病害为病毒病和茎基腐病,危害程度分别为4级和3级,炭疽病和疮痂病危害也较重,危害程度均为2级,其他病害危害较轻。害虫有28种,分别是黄胸蓟马、茶黄蓟马、红带蓟马、美洲棘蓟马、普通大蓟马、咖啡木蠹蛾、美洲斑潜蝇、橘小实蝇、斜纹夜蛾、双线盗毒蛾、绿丽刺蛾、白带锯蛱蝶、烟粉虱、温室白粉虱、柑橘粉蚧、木槿曼粉蚧、藤壶蜡蚧、茶角盲蝽、樟颈曼盲蝽、稻绿蝽、中稻缘蝽、茶小绿叶蝉、丽球瓢蜡蝉、绿鳞象甲、眼斑芫菁、白条豆芫菁、甘薯梳龟甲和朱砂叶螨。重要害虫为黄胸蓟马和咖啡木蠹蛾,危害程度均为3级,茶黄蓟马和美洲斑潜蝇的危害也较重,危害程度均为2级,其他害虫危害较轻。软体动物3种,分别是灰巴蜗牛、同型巴蜗牛和一种尚未鉴定的蛞蝓。本研究明确了海南百香果种植区病虫害具体种类,新发现百香果病害1种和害虫24种,为海南百香果病虫害的精准防控提供技术支撑。     

Interactive Effects of Sodium and Potassium on the Growth and Photosynthesis of Spinach and Komatsuna

Abstract

Two cultivars of spinach and one cultivar of komatsuna were sand cultured using a nutrient solution with Na and K in various combinations. The growth (fresh weight of shoot) of spinach cv. Atlas was significantly increased when 1.4 mM KC1 of the 7 m M KO was replaced with 1.4 mM NaCl, although the growth was reduced when more KC1 was replaced with NaCl. In another spinach cv. All Right, however, NaCl substituting for 20% of KC1 showed no significant effects. In komatsuna, Na used in place of K at any ratio reduced the growth. The growth of spinach cv. Atlas was increased by applying 20 mM NaCl, irrespective of K dose (480 - 2400 mg K₂O per 1/2000 a Wagner pot). The growth of spinach cv. All Right was also increased by 20 mM NaCl when K was at a deficient level (480 - 960 mg K20 per pot), but was not when K was at: an excessive level (1920 - 2400 mg K₂O per pot). In komatsuna, 20 mM NaCl reduced the growth. In spinach, Na prevented the decrease of the photosynthetic rate and stomatal conductance caused by K deficiency.     

白砂糖干燥与冷却机理及影响

砂糖的含水量、装包温度和仓储条件对其贮存保质具有重要影响。本文从白砂糖的含水分特性、干燥机理和生产过程环节等对白砂糖干燥与冷却的影响进行深入分析。由于结晶过程的包裹现象,砂糖含水分可分为表面和内部水分,白砂糖干燥过程只能去除前者。生产过程中煮糖、分蜜操作对内部水分含量有影响。贮存过程的内部水分的扩散是砂糖降质的根本原因,而装包温度和贮存条件是影响内部水分扩散的外在条件。     

Characteristics of photosynthesis and conductance of potato canopies and the effects of cultivars and transient drought

Gas-exchange characteristics of potato (Solanum tuberosum L.) canopies were determined with crop enclosures under condition of optimal water supply, during soil water depletion, and during recovery from drought-stress. The plants were grown under a rainshelter in large containers with 2-m² surface area. Control plants received water throughout the growth period. In Expt. 1, transient drought was imposed by interrupting water supply completely for 22 days. During the 33-day period of drought treatment in Expt. 2, the stressed plants received half the amount of water that was given to the control plants (irrigations 2–3 times per week).

During soil water depletion, stomatal conductance of the canopy was reduced earlier and more than photosynthesis. This resulted in a lower internal carbon dioxide concentration in the leaves of stressed plants and a higher ratio between photosynthesis and stomatal conductance. The value of that ratio increased as soil water potential dropped.

Water-use efficiency ( ) increased during drought stress. The cultivar Bintje showed a larger ratio between photosynthesis and stomatal conductance of the canopy and a higher than cv. Saturna, both for optimal water supply and during drought stress.

Photosynthesis and conductance of the canopy started to recover immediately upon rewatering, even when relative values had declined to 20–30% during the preceding stress period. After release from stress, the leaves in the top layer of the canopy had a higher stomatal conductance in treated plants than in control plants.     

苯醚甲环唑和嘧菌酯在水稻中的残留消解动态及残留分析

本文建立了气质联用仪测定稻田环境中苯醚甲环唑和嘧菌酯的残留分析方法,对苯醚甲环唑和嘧菌酯在水稻、土壤和田水中的消解动态和残留规律进行了研究。苯醚甲环唑和嘧菌酯在糙米、稻壳、植株、土壤和田水中的最低检测浓度均为0.20 mg/kg,最小检出量为0.2 ng,在不同样品中的平均加标回收率为80.8%~109.5%,相对标准偏差在1.7%~19.7%之间。田间试验结果表明,苯醚甲环唑和嘧菌酯在水稻植株和田水中的残留消解动态规律均符合一级动力学反应模型,苯醚甲环唑在水稻植株和田水中的残留消解半衰期分别为6.3~11.6 d和1.4~11.6 d;嘧菌酯在水稻植株和田水中的残留消解半衰期分别为3.6~8.7 d和2.9~23.1 d。以推荐剂量600 g/hm2和1.5倍推荐剂量900 g/hm2,最多施药3次,距最后一次施药15 d时,苯醚甲环唑和嘧菌酯在糙米中的最高残留量分别为0.461 mg/kg和0.634 mg/kg,低于我国国家标准《食品中农药最大残留限量》(GB2763-2014)中规定的糙米中苯醚甲环唑最大残留限量0.5 mg/kg和欧盟、美国规定的糙米中嘧菌酯最大残留限量5.0 mg/kg。