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为了促进园林花卉的科学养护,以4种北方园林草本花卉马蔺(Iris lactea Pall.var.Chinensis(Fisch.)Koidz)、金娃娃萱草(Hemerocallis fulva cv.‘Golden Doll’)、美国石竹(Dianthus barbatus f.American)和荷兰菊(Aster novi-belgii)为研究对象,通过室内条件下控制土壤相对含水量,研究3个不同土壤相对含水量水平下(正常含水(CK)、中度干旱(MS)、重度干旱(SS))4种园林花卉植物种苗生长过程中地上地下部分器官的抗旱特征,并采用隶属函数法评价这4种植物的抗旱能力。结果表明:(1)随着土壤相对含水量减少,马蔺的茎叶(含功能叶)和根系含水量均降低,根干重、根系长度均升高,根表面积随之升高;(2)金娃娃萱草在MS处理下根长、平均根直径、根表面积、根干重、根含水量、比叶重、茎叶干重、茎叶含水量均最高,表明金娃娃萱草苗期水分需求较低,根叶水分利用统一高效;(3)美国石竹根干重CK最高,MS与SS两处理差别不大,地上干重3种处理无明显差异。根含水与地上茎叶含水变化一致,先升高后降低,其它指标在不同水分处理下变化规律不明显;(4)荷兰菊在各土壤含水量处理下,根系生长变化与吸水特征不明显;(5)利用隶属函数综合评价4种植物抗旱能力的结果表明,金娃娃萱草的抗旱能力最强,马蔺和美国石竹次之,荷兰菊的抗旱能力较弱。 相似文献
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Assessing morphological characteristics of elite cotton lines from different breeding programmes for low temperature and drought tolerance 
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下载免费PDF全文 B. Singh E. Norvell C. Wijewardana T. Wallace D. Chastain K. R. Reddy 《Journal of Agronomy and Crop Science》2018,204(5):467-476
Cotton breeders in the United States strive to develop region‐specific genotypes adapted to low temperatures and variable soil moistures during early‐season planting. Nine elite upland cotton germplasm (Gossypium hirsutum L.) lines, representing public breeding programmes from nine states across the cotton belt, were evaluated for cold and drought stresses during seed germination and seedling growth stages. Lines were subjected to three treatments, such as low temperature well‐watered (22/14°C, WW), optimal temperature drought stress (30/22°C, DS) and optimal temperature well‐watered (30/22°C, WW; control), to examine genotypic variability for cold and drought tolerance. The treatment including drought stress was irrigated at 50% of the control. Shoot and root traits measured at 25 days after planting were significantly affected by drought and low temperature, where significant genetic variability among lines was observed for both shoot and root parameters. Response indices were developed to quantify variation in the degree of tolerance among the lines to low temperature and drought. Accordingly, OA‐33 was identified as the most low‐temperature‐tolerant line and Acala 1517‐99 as the most drought‐tolerant line. Identification of both cold‐ and drought‐tolerant genotypes suggests existing genotypic variability could provide breeders the opportunity to improve cultivar response to early‐season drought or cold conditions. 相似文献
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David J. Hobson Mary A. Harty David Langton Kevin McDonnell Saoirse R. Tracy 《Soil Use and Management》2023,39(1):198-208
Winter wheat (Triticum aestivum L.) is an important cereal crop in the temperate climates of western Europe. Root system architecture is a significant contributor to resource capture and plant resilience. However, the impact of soil type on root system architecture (RSA) in field structured soils is yet to be fully assessed. This work studied the development of root growth using deep cultivation (250 mm) during the tillering phase stage (Zadock stage 25) of winter wheat across three soil types. The three sites of contrasting soil types covered a geographical area in the UK and Ireland in October 2018. Root samples were analysed using two methods: X-ray computed tomography (CT) which provides 3D images of the undisturbed roots in the soil, and a WinRHIZO™ scanner used to generate 2D images of washed roots and to measure further root parameters. Important negative relationships existed between soil bulk density and root properties (root length density, root volume, surface area and length) across the three sites. The results revealed that despite reduced root growth, the clay (Southoe) site had a significantly higher crop yield irrespective of root depth. The loamy sand (Harper Adams) site had significantly higher root volume, surface area and root length density compared with the other sites. However, a reduction in grain yield of 2.42 Mt ha−1 was incurred compared with the clay site and 1.6 Mt ha−1 compared with the clay loam site. The significantly higher rooting characteristics found in the loamy sand site were a result of the significantly lower soil bulk density compared with the other two sites. The loamy sand site had a lower soil bulk density, but no significant difference in macroporosity between sites (p > 0.05). This suggests that soil type and structure directly influence crop yield to greater extent than root parameters, but the interactions between both need simultaneous assessment in field sites. 相似文献
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Centaurea stoebe is native to Europe and Western Asia and was introduced into North America in the late 19th century, where it has become highly invasive. In its native range, C. stoebe occurs in two cytotypes, namely diploids (2n = 18) and tetraploids (2n = 36), but only the tetraploid form has been identified in the invaded range. We used special growth pouches to determine whether diploid and tetraploid cytotypes from the native range differed in root growth and architecture. We grew seeds from five populations of each cytotype in growth pouches during a period of sixteen days and measured root growth traits both by hand and using a root‐scanning software package (WinRHIZO). Tetraploid cytotypes had significantly larger total root length, taproot length, surface area, root volume, above‐ and below‐ground biomass and root to shoot ratios than diploid cytotypes. We suggest that increased early root growth of tetraploid cytotypes as compared with diploids may be one factor that pre‐adapted them towards the colonisation of warmer and drier climates in Europe and North America, where tetraploids are currently expanding and invasive respectively. 相似文献
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High-throughput phenotyping of crop root system architecture using digital image analysis requires costly special software (WinRHIZO). Novel freeware, ImageJ, has also been developed for the similar purpose, but the presetting of the threshold to create root binary images makes this method time-consuming. This study compares the 16 algorithms available in the ImageJ for processing of rice root images. Among the algorithms, the Triangle algorithm proved to be the best binary method, where the coefficient of correlation between ImageJ-estimated and WinRHIZO-estimated root lengths is extremely high (r = 0.986). However, using the Triangle algorithm, ImageJ overestimated the rice root length compared with WinRHIZO. By multiplying the values obtained using ImageJ by 2/3, the estimates closely corresponded to those estimated by WinRHIZO. The correspondence of root lengths estimated using WinRHIZO and ImageJ with Triangle algorithm was valid for roots of various morphologies, and for rice plants grown in uplands, rainfed lowlands, and irrigated lowlands. This report proposes the completely automated estimation of rice root length using freeware ImageJ with the appropriate threshold algorithm for image processing. 相似文献
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