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1.
通过对直播短季棉不同密度和不同棉太金施用量进行组合,以达到简化栽培并构建适于机械采收的早熟棉群体的目的。试验结果表明,喷施棉太金和增密处理对棉花生长具有较好的调控作用,其中：（1）单位面积相同棉太金施用量下,密度增大,单株叶面积、果枝数、总果节数、成铃数减少,株高、干重、果枝长度、始节位、始节高度下降,小区产量提高;（2）相同密度下,单位面积棉太金施用量增大,单株叶面积、果枝数、总果节数、成铃数减少,株高、干重、果枝长度、始节位、始节高度、小区产量下降。试验中单铃重和衣分未受明显影响。 相似文献
2.
杏棉间作复合系统中棉花生长及生产特性的研究 总被引：8，自引：1，他引：7
以大田棉花为对照,与杏、棉间作下棉花的株高、LAI、产量及其构成因素进行比较研究。结果表明,杏、棉间作下棉花的株高和LAI相比对照均有不同程度的减小,且随着距杏树垂直距离的增加,其变化呈偏态分布趋势;间作下棉花的铃重、株铃数、有效果枝数和衣分相比对照均有一定的减少,各处理与对照间单株铃数和果枝数差异极显著,间作对产量性状的影响大小依次为:有效果枝数株铃数铃重衣分;间作减少了棉花的单位面积子棉产量和皮棉产量,各处理与对照间差异极显著;在杏、棉间作下试验的3个品种中鲁棉研28最为稳定。 相似文献
3.
中棉所48是中国农业科学院棉花研究所最新培育成功的大铃型抗虫杂交棉新品种。笔者根据3年的试种示范,结合该品种在长江中下游沿江平原几年种植情况,总结了一套该品种高产模式化栽培技术。1群体结构中棉所48在长江平原最适宜种植密度为每公顷1.95万株,株高110～130cm,果枝23个,单株成桃40～50个(其中伏前桃占5%～10%,伏桃55%～60%,秋桃35%～40%),每公顷总桃82.5万～97.5万个,铃重6.5g以上,衣分38%～40%,每公顷产子棉4500～6000kg。如果天气合适,栽培技术、肥力能够到位,成桃可达112.5万个左右,产量可高达7500kg左右。2栽培技术2.1苗期4月10… 相似文献
4.
川棉243产量构成规律及高产栽培途径探讨 总被引：1，自引：0，他引：1
对川棉２４３产量构成及高产栽培因素分析。结果表明,密度、铃数、铃重和衣分与产量密切相关,是产量构成的主要因素,其中铃数对产量的影响最大,其次是密度、铃重、衣分;铃数与果枝、果节和结铃率相关密切,其中结铃率对铃数的影响最大,其次是果节、果枝。 相似文献
5.
不同类型土壤棉花产量构成因素及棉铃空间分布研究 总被引：1，自引：0，他引：1
研究了膜下滴灌不同类型土壤棉花产量构成因素及棉铃空间分布规律。结果表明：产量构成各因素与皮棉产量之间均为正相关关系,且子棉与皮棉、铃数,皮棉与衣分、子数、地上干重、铃重,子数与地上干重的相关系数达极显著水平。壤土结铃能力最强,其次为粘土,单株成铃最少的是沙土地。从棉花不同果枝结铃的空间分布看,中部果枝结铃数高于棉株下部和上部,其中以壤土最高。不同类型土壤的棉田应进一步提高棉铃中部果枝成铃率,以提高棉花的品质;并进一步挖掘上部铃和外围铃的潜力,以提高棉花的产量。沙土地,应充分提高棉株的上部成铃率。 相似文献
6.
Bt基因导入对棉花农艺性状的影响 总被引：5，自引：0，他引：5
从棉花产量、纤维品质和抗虫性状等六个方面比较系统地阐明了 Bt基因导入对棉花农艺性状的影响。这些效应具体表现为 :结铃性、纤维比强度和抗虫性提高 ;单株果枝数、单株果节数、棉铃长度、棉铃体积、棉铃经济系数、铃重、衣分、纤维长度和麦克隆值下降。 Bt基因导入引起的结铃性增强效应与铃重、衣分减弱效应相平衡 ,使转 Bt基因棉GK- 1 2与受体品种泗棉 3号的皮棉产量持平。同时棉铃外形由圆锥形突变为卵圆形 ,铃柄长度大幅度增加。 GK- 1 2与泗棉 3号的杂种一代在植株形态性状、产量性状和棉铃经济性状上具有明显的杂种优势 ,其杂种优势表现的遗传基础来源于生态型和选择方向的差异 相似文献
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棉花种植方式和密度效应研究 总被引：3，自引：0，他引：3
以JX013为材料，在湖南浏阳研究了不同种植密度（18000、36000、54000株/hm2）、不同种植方式（直播、漂浮育苗移栽、营养钵育苗移栽）对棉花生长发育及产量、品质的影响。结果表明：在同一种植方式中，生育期随密度的增加而延长，株高、果枝数、单株成铃数随密度增高而降低，单位面积总铃数、籽棉产量随密度增高而增加；在同一密度下，生育期以直播棉最短，株高、果枝数、单位面积总铃数、籽棉产量以直播棉最大；不同处理对棉花铃重、衣分、衣指、子指、纤维品质影响不显著。 相似文献
11.
Xiansheng Zhang Xiaoning Tang Ran Wang Rui Wang Xiong Yan Meiwu Shi 《Fibers and Polymers》2017,18(8):1421-1430
Thermal degradation behaviors and fire retardant properties of poly(1,3,4-oxadiazole)s (POD) and poly(m-phenylene isophthalamide) (PMIA) fibers were investigated. The thermal gravimetric analysis (TGA) demonstrated that POD exhibited higher onset thermal degradation temperature (Tonset) than PMIA, exceeding nearly 80 °C. The thermal degradation kinetics, evaluated by the modified Coats-Redfern method, displayed that the apparent activation energy (Ea) of POD and PMIA fibers was similar when the conversion rate (α) ranges from 0.2 to 0.5, while with the α from 0.6 to 0.8, the Ea of POD was significantly lower than that of PMIA. The fire retardant performance of POD and PMIA fibers were evaluated by cone calorimeter under heat fluxes of 35, 50 and 75 kW/m2, during which the temperature of the fibers were monitored by a thermocouple. Surprisingly, POD fibers showed inferior fire retardant performance in comparison with PMIA, with lower time to ignition (TTI) and higher peak heat release rate (PHRR). The origin of the different fire retardant properties of both fibers was revealed by analyzing the residual chars and gaseous products during thermal pyrolysis. The morphology confirmed that stable and compact chars can be formed in PMIA. In addition, the Fourier Transform Infrared Spectroscopy (FTIR) characterization of the residual char revealed that POD can form carbonaceous chars at the heat flux of 50 kW/m2, while the heat flux of PMIA was 75 kW/m2. The pyrolysis products characterized by pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) indicated that POD can be pyrolyzed completely at 600 °C, while the temperature of PMIA was 700 °C. 相似文献
12.
茶叶多糖铁的合成及其铁含量的测定 总被引：8，自引：0，他引：8
用热水浸泡法从粗老茶叶中提取茶叶多糖,在碱性条件下,茶叶多糖水溶液与三氯化铁反应合成茶叶多糖铁配合物(TPC),并用邻菲罗啉分光光度法和原子吸收光谱法测定TPC中铁(Ⅲ)的含量。实验结果表明:TPC是深棕红色无定型粉末,易溶于水,在pH值3~12范围内不沉淀,不水解。TPC中铁(Ⅲ)的含量:邻菲罗啉分光光度法测定结果为20.71%,原子吸收光谱法测定结果为20.13%。 相似文献
13.
《Journal of Crop Improvement》2013,27(2):287-298
Summary It is well known that C4 crops have a lower water requirement than C3 crops. Reasons for the difference are not well understood. Therefore, hydraulic resistance of sorghum [Sorghum bicolor (L.) Moench] (C4) and sunflower (Helianthus annuus L.) (C3) was determined to see if it might be one explanation for the lower water use of crops with the C4 photosynthetic pathway. Plants were grown under greenhouse conditions in pots with soil, which was well watered (soil matric potential of ～0 MPa) or allowed to dry (soil matric potential of ?0.038 MPa and ?0.065 MPa for sorghum and sunflower, respectively). Hydraulic resistance was calculated in two ways: (1) using the classic Ohm's law analogue, which assumes that the relation between flux (transpiration) and difference in water potentials of the soil and plant is linear and (2) using an equation that considers diurnal changes in leaf water content along with transpiration and difference in water potentials. Because change in leaf-water content during a day was small, hydraulic resistances calculated by the two methods resulted in similar values. Sorghum had a linear relationship between flux and difference in potentials (constant hydraulic resistance), but sunflower had a nonlinear one (variable hydraulic resistance). The hydraulic resistance of watered sunflower increased only slightly during a day and averaged about 40 MPa m2 s mol?1, which was 3.5 times less than that of watered or water-stressed sorghum (-140 MPa m2 s mol?1). The hydraulic resistance of water-stressed sunflower increased steeply during a day and by the end of the day it had a hydraulic resistance that approached that of sorghum. 相似文献
14.
烟草花叶病毒(TMV)和马铃薯X病毒(PVX)的提纯及抗血清的制备 总被引：6，自引：1，他引：5
在温室内将提纯的ＴＭＶ和ＰＶＸ病毒，通过摩擦接种在普通烟（Ｎｉｃｏｔｉａｎａ ｔａｂａｃｕｍＬ．）上做为繁毒植物。通过ＰＥＧ沉淀和差速离心，获得提纯病毒。病毒含量分别为２１．４２ｍｇ／１００ｇ鲜重和２４．５０ｍｇ／１００ｇ鲜重。在紫外分光灯下测定ＯＤ值，分别在２４８ｎｍ（ＴＭＶ）和２４６ｎｍ（ＰＶＸ）为最低，２６０ｎｍ为最高。消光系数ＯＤ２６０／２８０分别为１．２０和１．２２。提纯抗原进行回接试验，指示植物产生明显症状，用Ｆｒｅｕｎｄ佐剂分三次肌肉免疫家兔，所得抗血清效价为１：２０４８，然后利用（ＮＨ_４）_２ＳＯ_４提取球蛋白，并利用ＨＲＰ进行酶标记，制备出的抗血清现已应用于生产。 相似文献
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《杂交水稻》2014,(4):77-80
以赣晚籼36号为材料,通过水培试验,比较研究了不同质量浓度的Cr3+和Cr6+对水稻种子发芽和幼苗生长的影响。结果表明,Cr3+在低质量浓度时能促进水稻种子发芽和幼苗生长,而高质量浓度时抑制水稻种子发芽和幼苗生长;Cr6+对水稻种子发芽、苗高和植株鲜重也有低促高抑现象,但对幼苗根长、根干重和苗干重则均表现为抑制作用,且随着质量浓度的升高,毒性加强。Cr6+的最小EC50是与根长抑制率相对应的6.19 mg/L,Cr3+的最小EC50是与根长抑制率相对应的11.57 mg/L,Cr6对水稻种子发芽和幼苗生长的毒性大于Cr3+,铬对水稻根生长的毒害程度大于对种子发芽及地上部分生长的毒害程度。 相似文献
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I. C. Obizoba J. U. Anyika 《Plant foods for human nutrition (Dordrecht, Netherlands)》1994,46(2):157-165
The baobab milk and fermented baobab/acha flour mixtures were analyzed chemically for their proximate, ascorbate, mineral and antinutrient composition. The dry pulp scraped from baobab fruits was kneaded, made into solution, extracted through cheese-cloth and stored frozen until analyzed. The acha and baobab grains were cleaned, fermented for 24 to 120 hours, dried and hammermilled into fine flours. The unfermented flours served as controls. The standard assay methods of AOAC were selected for use for the analysis of the nutrients and the antinutrients. The mixtures were composed of 70% acha and 30% baobab flours (70:30 protein basis). The baobab milk contained more protein (1.5%) and minerals (Fe, 17.8 mg; Ca 134.2 mg) than those of human milk (protein, 1.3%, Fe, 0.2 mg, Ca 30 mg) and cow milk (Fe, 0.1 mg; Ca 1.20 mg) and most leading national commercial infant formulas e.g. cerelac (Fe, 10.0 mg). The composite flours contained more nutrients than the baobab or the acha flour alone. The BF96 had greater advantage over other BF flours as a supplement to acha. The mixtures are within the reach of lower income group and can be incorporated into their diets. 相似文献
17.
《Crop Protection》1987,6(1):7-12
Field experiments are described in which sex-attractant lures for male pea moth, Cydia nigricana (F.), were compared in the UK and France, to explain earlier anomalies between results in the two countries. These were caused by differences in formulation, rather than in trap design or crop; there was no evidence for the existence of different biological races. Freshly exposed lures containing (E,E)-8,10-dodecadien-1-yl acetate (E,E8,10–12:Ac) from France (INRA) or the UK (Rothamsted) attracted similar numbers of moths in both countries, but the INRA lures rapidly became less attractive because they did not contain antioxidant to prevent the formation of a product repellent to male moths. The experiments in France also confirmed that E,E8,10–12:Ac is a more powerful attractant than (E)-10-dodecen-1-yl acetate for the pea moth, in agreement with previous results in the UK. Similar experiments, only in France, with the lucerne moth, Cydia medicaginis (Kuzn.), confirmed that E,E8,10–12:Ac is a powerful attractant, and showed that field-exposed E,E8,10–12:Ac is repellent to this species also. 相似文献
18.
Hye Min Jung Eun Mi Lee Byung Chul Ji Sung Ok Sohn Han Do Ghim Hyunju Cho Young A Han Jin Hyun Choi Jae Deuk Yun Jeong Hyun Yeum 《Fibers and Polymers》2006,7(3):229-234
Poly(vinyl acetate) (PVAc)/poly(vinyl alcohol)(PVA)/montmorillonite (MMT) clay nanocomposite microspheres with a core/shell
structure have been developed via a suspension polymerization approach. In order to prepare the PVAc/MMT and PVAc/PVA/MMT
nanocomposite microspheres, which are promising precursor of PVA/MMT nanocomposite microspheres, suspension polymerization
of vinyl acetate with organophilic MMT and heterogeneous saponification were conducted. A quaternary ammonium salt, cetyltrimethylammonium
bromide, was mixed with the MMT in the monomer phase prior to the suspension polymerization. The rate of conversion decreased
with an increase in MMT concentration. The incorporation of MMT into the PVAc was verified by FT-IR spectroscopy. Organic
vinyl acetate monomers were intercalated into the interlayer regions of organophilic clay hosts and followed by suspension
polymerization. Partially saponified PVA/MMT nanocomposite microspheres with a core/shell structure were successfully prepared
by heterogeneous saponification. 相似文献
19.
Spinetoram is a fermentation insecticide, derived from the actinomycete Saccharopolyspora spinosa. It works by disrupting the GABA-gated chloride channels and by causing persistent activation of insect nicotinic acetylcholine receptors. This study aimed to evaluate the efficacy of spinetoram for control of neonate larvae of both oriental fruit moth (OFM) Grapholita molesta (Busck) and codling moth (CM) Cydia pomonella (L.) in semi-field and laboratory trials. OFM and CM neonate larvae responded similarly to spinetoram, which showed high efficacy on both species. In semi-field experiments, regression analysis of the percentage of damaged fruits as a function of days after treatment showed a better performance of the highest spinetoram dose (10 g a.i./hl) in comparison with the maximum recommended field dose of the reference product emamectin benzoate (2.85 g a.i./hl). Surface-treated diet assays revealed LC50 values of 6.59 and 8.44 ng a.i./cm2 for neonate larvae of OFM and CM larvae, respectively. High percentages of mortality were recorded on both species after 24-h exposure to treated diet. For these reasons spinetoram could be considered a valuable tool in IPM strategies for OFM and CM control. 相似文献
20.
Previous clarification of the relationships between insect populations and damage by cereal pests has enabled the effect of combined pest infestation on the yield of winter wheat to be analysed more thoroughly. The cereal aphids Macrosiphum avenae (Fabr.) (Sitobion avenae) and Rhopalosiphum padi (L.), each in combination with the cereal leaf beetle Oulema melanopus (L.), were investigated in pot trials which enabled interactions between the combined pest populations to be studied also. Although intraspecific competition was observed for each pest population, there was no interspecific adverse effect of density on population increase. With increasing population densities of the pests in combination, the relative contribution of each species to the combined yield losses decreased. Consequently, there was no summation of individual losses, but a reduction of up to 24·3%. The ability of the cereal plant to compensate for losses may be responsible for this ‘buffering effect’, which apparently is attributable to increased dry-matter production in the presence of large combined pest populations. These results suggest that the existing economic thresholds relating to the effects of cereal aphids and cereal leaf beetle on yields of winter wheat require modification. 相似文献