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31.
甘蓝型油菜耐湿种质资源的快速筛选 总被引:1,自引:7,他引:1
将不同来源甘蓝型油菜种质资源种子发芽60h,取露白种子进行密闭水淹缺氧处理12h后转入砂床继续 发芽,未作缺氧处理的露白种子作为对照, 6d后测定发芽相关性状,根据发芽性状差异评价油菜耐湿性。结果表 明,与对照相比,缺氧处理对油菜幼苗生长具有显著的抑制作用:平均相对根长为24. 7% ,平均相对茎长和鲜重分 别为59. 7%、69. 1% ,平均相对成苗率为79. 4% ,平均相对活力指数(RV I)为0. 49。相关分析表明, RV I、电导率、相 对成苗率、相对根长、相对茎长、相对鲜重等各发芽相关性状均相互呈极显著相关,其中相对活力指数可以全面评 估甘蓝型油菜在缺氧胁迫后的恢复生长能力,而电导率可以作为耐湿材料高通量早期筛选的指标。不同材料RV I 呈正态分布,变幅为0. 04~0. 92,表明甘蓝型油菜种质资源耐湿性存在十分丰富的遗传差异,其中03P79 - 1、03P62 - 5、中双8号等品系(种)具有较强的耐湿性,可以作为耐湿性资源加以利用。 相似文献
32.
滨海盐土暗管排水降渍脱盐效果研究 总被引:6,自引:1,他引:6
在江苏省滨海盐土按不同埋深和间距埋设地下暗管,其降渍、脱盐作用主要表现在丰水期(7-9月)内,在试验区范围内,10m间距暗管的降渍效果最显著,10m和15m间距暗管的脱盐效果相差不明显;在较小间距(10m)时,1.4m埋深暗管的降溃效果优于1.2 m埋深,埋设间距≥15m后,埋深对暗管降渍效果无明显影响,而在所有埋设间距处理中,1.4m埋深暗管的脱盐效果都优于1.2m埋深.综合比较分析各相关试验结果,并考虑暗管埋设的初期投资和后期维护成本,推荐间距15m、埋深1.4m为江苏滨海盐土降渍脱盐的地下暗管工程最佳布设参数. 相似文献
33.
小麦叶片RuBP羧化酶活性对湿害逆境的响应能力及亲本效应分析 总被引:2,自引:0,他引:2
用^14C同位素示踪法研究了6个小麦品种叶片的RuBP羧化酶活性对孕穗期湿害逆境的响应能力及其产量性状表现;用完全双列杂交法测定了9个小麦亲本耐湿性的配合力。结果表明:在孕穗期湿害逆境下,不同品种间的RuBP羧化酶活性下降程度存在明显差异,这种差异与主茎绿色叶片数和产量性状的变化相一致,配合力分析结果表明,亲本之间一般配合力差异达极显著水平,组合间特殊配合力效应存在显著差异,说明小麦品种的耐湿性受 相似文献
34.
岩溶内涝灾害是亚热带湿润气候条件下岩溶地区特有的一种与岩溶生态环境和人类活动密切相关的灾害类型。广西岩溶区的主要岩溶内涝有峰丛洼地内涝、峰丛(峰林)谷地内涝、岩溶平原内涝、岩溶区与非岩溶区接触过渡带内涝4种类型,其中,峰丛洼地内涝的发生率最高、面积最大。水文二维结构、降水、人为干扰是影响岩溶峰丛洼地内涝诸多因素中的主要因子。峰丛洼地内涝灾害的分类、分布、地质地貌特征、居民点和耕地分布情况、治理工程的投资效益比和内涝形成原因决定了应首先采取预防、综合治理相结合的普适性措施,在内涝最严重的低峰丛洼地和高峰丛洼地区域,还要实施针对性的水利工程和生态措施,保障该区域生态经济的可持续发展。 相似文献
35.
五种草坪草对水涝胁迫的反应及耐涝评价 总被引:1,自引:0,他引:1
以沟叶结缕草(Zoysia matrella(L.)Merr.)、大穗结缕草(Z.macrostachya Franch.et Sav.)、普通狗牙根(Cynodon dactylon(L.)Pers.)、青岛结缕草(Z.japonicacv QingDao)和高羊茅品种翠碧(Festuca arundinacea cv Triplet)为材料,对其在水涝胁迫下草坪草形态、生理指标变化进行了研究,并采用隶属函数法对其耐涝性进行评价,以期为江南中下游地区草坪草的栽培提供试验依据。结果表明:随水涝时间的延长,叶片枯黄率逐渐增加,叶片相对电导率(REC)、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性以及游离脯氨酸(Pro)和可溶性总糖(TSC)含量5个生理指标在水胁迫15 d时均比对照明显增加;以REC,SOD和POD活性以及Pro和TSC含量为指标,对5个草种的耐涝隶属函数值进行计算,并对其耐涝适应性进行综合评价,得出5个草种的耐涝性顺序为大穗结缕草>普通狗牙根>翠碧>青岛结缕草>沟叶结缕草。 相似文献
36.
Physiological and growth responses of ‘Pantin’ and ‘Magana’ mamey sapote (Pouteria sapota) trees to continuous and cyclical flooding were studied in a series of experiments. Trees were grown in containers in a very gravelly loam soil and were subjected to continuous flooding of the root zone for 30–66 days (Experiments 1 and 2) or alternating flooding–unflooding cycles for 50 days (Experiments 3–5). For all experiments, the control treatment consisted of nonflooded trees. Net CO2 assimilation (A) and stomatal conductance (gs) decreased within 3 days of continuous flooding and internal CO2 concentration was significantly higher in leaves of flooded than nonflooded plants. In the cyclic flooding experiments, trees were flooded in 3- to 6-day cycles and then unflooded for the same time periods. Stomatal conductance and A decreased within 3 days of flooding, leaf epinasty occurred between days 5 and 10, leaf senescence and abscission occurred between days 15 and 30, and branch dieback and tree death occurred between days 30 and 60. Three cycles of 3-day flooding and 3-day recovery of trees had little effect on leaf gas exchange of ‘Magaña’ trees. Similarly, ‘Pantin’ trees survived 3 cycles of 6 days of flooding interspersed with 3–6 days of recovery despite consistent decreases in gs and A during flooding. Stomatal conductance and A of both mamey sapote cultivars decreased within a few days of flooding and this species appears to have intermediate flooding tolerance compared with other tropical fruit crops based on tree survival. 相似文献
37.
N.R. Hulugalle R. Jaya G.C. Luther M. Ferizal S. Daud Yatiman Irhas Z.A. Yufniati F. Feriyanti Tamrin B. Han 《CATENA》2009,77(3):224-231
On 26 December 2004, a tsunami caused extensive loss of life, damaged property and degraded agricultural land in the province of Aceh, Indonesia. While some of the associated soil chemical changes have been documented, information on soil physical properties is sparse. The objective of this study was to quantify physical properties of some tsunami-affected upland agricultural soils in Aceh, Indonesia. Soil was sampled approximately 21/2 years after the tsunami, from the 0–0.1 m, 0.1–0.3 m and 0.3–0.5 m depths in four sites in the villages of Kling Cot Aroun in Aceh Besar sub-district, Kuta Kruen in Aceh Utara sub-district, Udjong Blang Mesjid in Bireuen sub-district and Meue in Pidie Jaya sub-district on the east coast of Aceh. These sites were located within 1 km from the sea at elevations ranging from 0 to 5 m ASL. The soils were Ultisols except for Meue, which was an Entisol. Soil properties measured were bulk density, structural stability and particle size distribution. Soil water retention, pore-size distribution and saturated hydraulic conductivity were estimated by inserting the values of bulk density, clay, sand and silt contents into pedotransfer functions from the literature. The analyses conducted during this study did not permit us to ascertain what proportion of the soil particles were of tsunami-origin. Nonetheless, deposition of finer-textured material may have occurred in two of the sites. In comparison with the greyish-white, coarse textured soil in the rest of the profile, a finer-textured yellow horizon was present in the lower slopes of the Udjong Blang Mesjid site. At Meue, clay and silt contents were higher in the surface 0.3 m than in the 0.3–0.5 m depth, although a distinct horizon was absent. Particle size distribution in all sites was dominated by the sand fraction, although clay and silt contents were relatively high (20–30 g 100 g− 1) at Kuta Kruen. Among the sand fractions, fine sand (0.02–0.25 mm) was highest at Kling Cot Aroun, Kuta Kruen and in the “yellow horizon” at Udjong Blang Mesjid, making them more prone to hardsetting and compaction after intensive tillage. Soil compaction was present in all sites with that in the “yellow horizon” at Udjong Blang Mesjid being highest. The relatively low porosity in this layer may be beneficial, as it is likely to reduce the high rates of water drainage and nutrient leaching in this sandy soil. The more compacted soils were characterised by higher numbers of micropores (r, pore radius < 4.3 μm), lower water retention at saturation, smaller numbers of macropores (r > 14.3 μm), lower hydraulic conductivity and intensive gleying, indicating frequent waterlogging. The soils in all depths from Kling Cot Aroun and the “yellow horizon” at Udjong Blang Mesjid were very dispersive, that at Meue moderately dispersive in the 0.3–0.5 m depth but stable in the 0–0.1 m depth, and at Kuta Kruen very stable in all depths. Soil physical degradation was a feature of the soils examined, and its amelioration will be the key to improving and sustaining crop yields in these soils. Possible management interventions include organic amendments such as compost or manure, and minimum tillage options such permanent beds or zero tillage with retention of crop residues as in situ mulch together with suitable cover crops. 相似文献
38.
甘蓝型油菜发芽种子耐湿性的主基因+多基因遗传分析 总被引:8,自引:0,他引:8
油菜湿害是我国特有的自然灾害,对油菜种子发芽、出苗和幼苗生长造成严重影响,导致单产显著下降。为研究油菜种子发芽耐湿性的遗传规律,本文利用耐湿性遗传差异较大的2个甘蓝型油菜纯系中双9号和GH01的杂交后代衍生的世代家系群体构建油菜耐湿性遗传体系,并以主基因+多基因家系世代联合分析方法对油菜耐湿性的遗传规律进行分析。结果表明,中双9号×GH01组合的耐湿性的遗传受2对完全显性主基因+加性-显性多基因控制,表现为耐湿对不耐湿完全显性。该组合的第1对主基因加性效应与显性效应相等,为0.0696;第2对主基因的加性效应与显性效应相等,为0.0530。多基因加性效应为0.3275,显性效应为负值([h]= –0.2137)。主基因存在显性效应,该组合的耐湿性存在杂种优势,多基因显性效应为负,多基因显性效应使F1代耐湿性降低。F2家系的主基因遗传力为73.57%,表现出较高的遗传力,建议育种工作者对耐湿性在早期选择效率较高。 相似文献
39.
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