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31.
以棉花幼苗下胚轴和茎尖作为试验材料,通过添加不同浓度的外源茉莉酸合成抑制剂,观察棉花下胚轴生根及愈伤组织的形成率以及对茎尖分化的影响,探究茉莉酸合成抑制剂对棉花脱分化及茎尖培养的影响。结果表明,茉莉酸合成抑制剂可以显著地促进愈伤组织的生成,加快生根,但是会在一定程度上抑制愈伤组织POD及SOD的活性。当茉莉酸合成抑制剂浓度为0.075 mg·L~(-1)时,对生根及愈伤组织形成方面作用效果最显著。而在茎尖培养过程中,2.0 mg·L~(-1)的茉莉酸合成抑制剂在棉花茎尖培养初期对分生组织分化起显著促进作用,棉花生长量最大,植株SOD酶和POD酶活性最大。  相似文献   
32.
在新疆生态条件下,采用海岛棉新海35号研究同等用量3种施磷方式(犁地前全部撒施、犁地前撒施50%与作种肥施50%和全部作种肥施)对棉花农艺性状及产量的影响。结果表明:施磷方式对棉花生育进程的影响较小,各处理对新海35号棉花的农艺性状没有显著性的影响,P1处理可略为提高棉花花铃期叶面积指数,其中P1处理会略提高棉花后期的干物质积累量,以P1、P2处理的方式施磷肥,棉花的单株结铃数可提高4%~7%皮棉产量可提高12%~14.8%。  相似文献   
33.
Drought is a common abiotic stress that considerably limits crop production. The objective of this study is to explore the influence of water deficiency on the yield, physiologic and metabolomic attributes in upland cotton cultivars(Gossypium hirsutum L). Cotton cultivars, 'Ishonch' and 'Tashkent-6' were selected to study the relationships among their physiologic, metabolomic and yield attributes during water deficiency. Deficit irrigation was designed by modifying the traditional watering protocol to reduce water use. Results indicate that cotton cultivars respond differently to water deficit stress. Water deficit significantly influenced plant height, the number of internodes, and sympodial branches in both cultivars. However, yield components such as the number of bolls, boll seed, lint mass, and individual plant yield were significantly reduced only in 'Tashkent-6'. The leaf area decreased and the specific leaf weight increased in 'Ishonch' under deficit irrigation conditions. However, 'Tashkent-6' demonstrated significant water loss compared to 'Ishonch', and both cultivars showed reduced transpiration rates. Untargeted metabolite profiles of leaves showed clear separation in 'Ishonch', but not in 'Tashkent-6' under deficit irrigation compared to full irrigation. The individual metabolites such as proline and galactinol showed strong association with yield under water deficit stress. Moreover, this study indicates that leaf area and transpiration intensity influence yield during water deficiency. In summary, the correlation among morpho-physiologic, metabolic, and yield components significantly varied between the two cultivars under water deficiency. The flowering stage was sensitive to water stress for both cultivars. The direct relationship between physiology, metabolism, and yield may be a useful selection criterion for determining candidate parents for cotton drought tolerance breeding.  相似文献   
34.
[Objective] The genetic diversity of semi-wild cotton was abundant, so more new elite resistant genes could be found and applied to improve the resistance of cotton. The aim of this study was to primarily study on the regulation of response to salt-alkali stress, explore the method of integrated evaluation and characterize the resistance of semi-wild cotton. [Method] Four semi-wild and two cultivated Gossypium hirsutum accessions were evaluated for phonotypical, physiological and biochemical traits under alkali-salt versus normal conditions in hydroponic solutions. The alkali-salt tolerance was determined based on principal component analysis, cluster analysis, correlation analysis, grey rational analysis and analysis of variance. [Result] On the basis of the overall results, the alkali-salt stress tolerance of the six accessions was ranked as: Marie-galante85 > Latifolium32 > CRI16 > CRI12 > Latifolium40 > Latifolium130. Roots were found to be the most important responsive systems to complex alkali-salt stress. At seedling growth stage, the active scavenging system played a crucial role in response to alkali-salt stress. In addition, the salt tolerant and salt sensitive accessions showed different response tends towards leaf peroxidase, root ascorbate peroxidase and root catalase within 48 h, suggesting the accessions have different levels of response to salt stress. [Conclusion]Our study identified the most alkali-salt tolerant accessions and provided basic concept of complex alkali-salt tolerance mechanism within cotton accessions. And, our study provided a simple and rapid, highly accurate and precise method for evaluating salt resistance of cotton, and proved that the balance of ROS system play an important role in response to salt-alkali stress. Hence, mining of salt tolerant genes from these accessions may facilitate the development of novel salt tolerant variety.  相似文献   
35.
以新疆膜下滴灌棉田为试材,研究氮磷减量与液体有机肥配施对膜下滴灌棉田土壤养分的影响。试验设11个处理:(1)常规施肥(NP);(2)80%常规施肥(80%NP);(3)80%常规施肥+低量氨基酸有机肥(80%NP+LAA);(4)80%常规施肥+中量氨基酸有机肥(80%NP+MAA);(5)80%常规施肥+高量氨基酸有机肥(80%NP+HAA);(6)80%常规施肥+低量黄腐酸有机肥(80%NP+LFA);(7)80%常规施肥+中量黄腐酸有机肥(80%NP+MFA);(8)80%常规施肥+高量黄腐酸有机肥(80%NP+HFA);(9)80%常规施肥+低量沼液有机肥(80%NP+LBS);(10)80%常规施肥+中量沼液有机肥(80%NP+MBS);(11)80%常规施肥+高量沼液有机肥(80%NP+HBS);分别在蕾期、花期、成熟期采集0~20、20~40 cm土层土壤,测定土壤pH值、有机质、氮、磷、钾等有效养分含量。研究结果表明:(1)蕾期时,80%常规施肥配施高量黄腐酸、沼液有机肥显著降低了0~20 cm土层土壤pH值,并对提高土壤速效氮、速效磷含量效果最好。(2)花期时,80%常规施肥配施高量沼液有机肥对提高0~20 cm土层土壤有机质、速效磷含量效果最好。(3)成熟期时,80%常规施肥配施高量沼液有机肥对降低0~20 cm土层土壤pH值、提高土壤有机质含量效果最好。综上所述,新疆滴灌棉田应用80%常规施肥配施高量沼液有机肥效果最好,是新疆滴灌棉田提高土壤肥力和肥料利用率的有效途径。  相似文献   
36.
Cotton producers have substantially reduced their inputs(labor, nutrients, and management) mainly by adopting a shortseason cropping management that is characterized by late sowing, high density, and reduced fertilization with one-time application at the first bloom stage without lint yield reduction. However, it has been hypothesized that one-time fertilization at an earlier growth stage could be a more effective and economic management practice. A two-year field experiment was conducted by applying five fertilizer one-time fertilization at 0(FT1), 5(FT2), 10(FT3), 15(FT4), and 20(FT5) days after the first flower appeared in the field and one three-split fertilizer application taken as the conventional control(FT6), making six treatments altogether. Cotton growth period, biomass accumulation, yield, and its formation were quantified. The results showed that the one-time fertilization did not affect the cotton growth progress as compared to FT6, however, the total crop cycles for FT3–FT5 were 3 days shorter. FT1 produced the highest cotton lint yield(1 396 kg ha–1), which was similar to the FT6 but higher than the other treatments, and could be attributed to more bolls per unit area and higher lint percentage. Cotton yield was positively correlated with cotton plant biomass accumulated. FT1 had both the highest average(VT)(193.7 kg ha–1 d–1) and the highest maximum(VM)(220.9 kg ha–1 d–1) rates during the fast biomass accumulation period. These results suggest that one-time fertilizer application at the first flower stage might be an adjustment that is more effective than at first bloom, and allowed for easier decision making for application date due to non counting of plants with flowers is needed.  相似文献   
37.
为探究不同耐盐性棉花品种幼苗对盐胁迫的生理响应特征,以棉花耐盐品种中9806和盐敏感品种中S9612为材料,采用水培法,设置4个NaCl浓度梯度(0、100、150、200 mmol·L-1)来模拟不同强度盐胁迫条件。结果表明:随着盐浓度的增加,各棉花品种的可溶性糖(SS)含量上升,抗氧化酶活性呈先上升后下降的趋势;盐处理下,耐盐品种可溶性蛋白(SP)、脯氨酸(Pro)含量增加量高于盐敏感品种;S1处理(100 mmol·L-1 NaCl)中盐敏感品种丙二醛积累量较低,但在S2和S3处理(150、200 mmol·L-1 NaCl)中,耐盐品种丙二醛含量增幅(5.35%~6.83%)低于盐敏感品种(36.93%~77.34%),超氧化物歧化酶(SOD)、过氧化物酶(POD)活性增加量较大;低盐浓度(S1处理)下,盐敏感品种地上部分能够保持较少的Na+,高盐浓度(S2和S3处理)下,耐盐品种根中Na+增加量小于盐敏感品种,茎中K+、K+/Na+较高。综上表明,耐盐品种棉花通过增强渗透调节,提高抗氧化酶活性缓解膜脂过氧化,维持较高K+/Na+,从而提高棉花幼苗的耐盐性。  相似文献   
38.
播期对麦(油)后直播棉产量、品质及氮磷钾利用的影响   总被引:3,自引:0,他引:3  
为明确长江流域下游棉区麦(油)后直播棉生产的适宜播期,本研究以?中棉所50‘为材料,于2017—2018年进行大田试验,研究不同播期(5月15日、5月25日、6月4日、6月14日和6月24日)对直播棉产量、品质及养分利用的影响。结果表明,播期推迟,棉花生育进程推迟;花铃期日均温和日照时数降低、有效积温先升高后降低且以6月4日播期花铃期有效积温最高。可见,前3个播期棉花花铃期温光条件较好。棉株与生殖器官的生物量及氮磷钾累积量随播期推迟降低,且前3个播期的棉株生物量和养分累积进入较高速率累积期早于后2个播期的棉株。随着播期的推迟,直播棉成铃数与皮棉产量显著降低。与5月15日播期相比,其余4个播期直播棉的皮棉产量分别降低15.9%~16.9%、13.1%~16.9%、26.9%~33.5%、58.2~62.0%。100kg皮棉氮、磷和钾吸收量随播期推迟而增加,但养分利用效率降低。不同播期间,以6月4日和6月14日播期棉纤维综合品质较优。综上,本试验条件下,5月15日—6月4日是长江流域棉区麦(油)后直播棉获得较高产量的适宜播期,该播期内适当推迟播种有利于棉花优质纤维的形成。  相似文献   
39.
对2016-2017年引进的62个陆地棉新品种进行了形态特征、生物学特性和品质特性的鉴定及分析。结果表明:目前收集的新材料以中早熟棉为主,铃重以中等大小为主,衣分中等,悬殊较大,马克隆数值普遍偏大。  相似文献   
40.
起垄沟播和常规平播下滴灌棉田土壤水盐的运移   总被引:1,自引:0,他引:1  
为明确滴灌条件下植棉方式对土壤水盐运移的影响,采用田间调查与室内分析相结合的方法,在滨海重度盐碱地开展了起垄沟播和常规平播植棉方式下的水盐运移试验,调查了滴灌前后两种植棉方式不同点位及不同土壤深度的土壤水分、盐分和土壤溶液电导率等指标,分析不同植棉方式土壤水分、盐分和土壤溶液电导率的时空分布特征。结果表明:滴灌条件下起垄沟播的水分入渗深度和盐分淋洗深度均明显大于常规平播植棉方式,起垄沟播植棉膜下(0~20 cm)土壤溶液电导率明显低于常规平播植棉;滴灌对两种种植方式膜外土壤水分和盐分运移未产生明显影响。起垄沟播联合滴灌技术更有利于为棉花生长的水盐环境。研究结果可为盐碱地植棉提供理论参考和实践依据。  相似文献   
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