共查询到20条相似文献，搜索用时 83 毫秒
1.
2.
根区温度对甜瓜幼苗光合特性的影响 总被引：2，自引：0，他引：2
以甜瓜品种银帝3号和西州蜜1号为试材，采用有机生态型无土槽式栽培，研究了根区温度对甜瓜幼苗叶片叶绿素含量
、气体交换特性和叶绿素荧光参数的影响。结果表明：甜瓜幼苗叶片叶绿素含量、净光合速率（Pn）、气孔导度（Gs）、气
孔限制值（Ls）、蒸腾速率（Tr）、荧光产量（F）、光化学量子产量（Yield）、光化学猝灭系数（qP）、非光化学猝灭系
数（NPQ）均随着根区温度的降低而降低。非气孔限制是导致根区低温胁迫下甜瓜幼苗叶片光合作用下降的主要影响因素；PS
Ⅱ光化学活性抑制是甜瓜光合作用降低的重要原因之一。 相似文献
3.
4.
不同基质对甜瓜幼苗生长的影响 总被引：2，自引：0，他引：2
通过不同配方基质对甜瓜幼苗生长影响的观察,获得适于甜瓜育苗的高效低成本育苗基质.试验表明:不同基质对甜瓜幼苗的根长、叶面积、茎和根的干重影响较大,对茎粗、株高影响较小,播种后14～21d,基质对甜瓜幼苗的生长影响很大,株干重的日增长量相差1.201 mg.播种30 d以后,甜瓜幼苗的干物重增加明显减缓. 相似文献
5.
以伊丽莎白和玉金香2个甜瓜品种为材料,研究了昼夜低温(10℃/5℃,昼/夜)和夜间低温(20℃/5℃,昼/夜)处理对甜瓜幼苗生长及根系生理指标的影响.试验结果表明,与对照温度(25℃/18℃)相比,昼夜低温和夜间低温处理7d均显著抑制了甜瓜幼苗生长,且昼夜低温处理比夜间低温处理有更高的根系MDA含量,对甜瓜幼苗伤害程度... 相似文献
6.
低温胁迫对甜瓜幼苗叶绿素含量及荧光参数的影响 总被引：11，自引：0，他引：11
采用人工控温的办法,研究了30℃/20℃、21℃/12℃、15℃/8℃(昼/夜)3个温度条件下甜瓜的光合色素含量和叶绿素荧光参数.结果表明:低温条件造成了甜瓜幼苗叶绿素含量下降,并且随着温度的下降情况加剧;叶绿素荧光分析表明,在不同的低温胁迫下,甜瓜幼苗Fv/Fm、Fv/Fo和qP下降,qN升高,15℃/8℃条件下最为严重.说明低温胁迫使甜瓜叶光系统PSⅡ活性中心受损;低温使光化学反应的相对份额FPSⅡ下降,表明温度胁迫使光舍电子传递过程受抑制,光合电子传递速率下降. 相似文献
7.
１厚皮甜瓜对环境条件的要求１．１温度甜瓜整个生育期中，最适合的温度是２５～３５℃。萌芽期最低温度１５℃，最适３０～３５℃；幼苗生长最适２０～２５℃，由于甜瓜花芽分化在幼苗期就已经开始，因此２０～２５℃也是花芽分化的最适温度；果实发育最适３０～３５℃，... 相似文献
8.
9.
10.
以"激情"厚皮甜瓜为试材,设置4个处理(OU、HUP、HOP、HOU),分析不同温度环境对厚皮甜瓜物质分配、根系生长与根系活力的影响,以期为促进厚皮甜瓜的根系生长发育、提高吸收能力和减缓海南地区厚皮甜瓜生理性萎焉问题提供参考依据。结果表明:HUP,苗期抑制植株茎粗和根径的生长,中后期促进地上部及主根生长;在厚皮甜瓜生长的各生育时期,HOP和HOU处理主侧根长、根粗、干物质积累量均降低,同化产物向地上部分的分配比例大于地下部;HOP及HOU处理伤流液量与根系活力显著低于OU及HUP处理。综上所述,高温及地上部高温会抑制厚皮甜瓜根系的干物质分配导致根系不发达;适当增加根区温度可促进根系生长发育、提高根系活力和根系吸收能力。 相似文献
11.
根系限制对酿酒葡萄生长发育的影响 总被引：12，自引：0，他引：12
用10、20 和50 L 容积的塑料盆盆栽酿酒葡萄, 探讨了根系生长范围对地上和地下部生长的影响。各处理的根干物量由小到大依次为: 10、20、50 L。50 L 处理根量分别是20L 和10 L 的1. 78 倍和3. 38 倍。按直径将根分为粗根( > 3 mm) 、中级根(0. 5 ～3. 0 mm) 、细根( < 0. 5 mm) , 限根处理使细根量显著增加。同级根平均根长和根重无显著差别, 表明限根后根重减少是根数量减少之故, 而非根变短变细。地上部生长受限根处理影响显著, 干物量、叶质量、叶面积均显著降低。 相似文献
12.
西瓜根系分泌物对西瓜种子萌发及幼苗根系活力的影响 总被引：1，自引：0，他引：1
以对西瓜枯萎病菌抗性不同的西瓜抗病品种(甜妞)、感病品种(天使)和不同的西瓜嫁接砧木(南瓜、葫芦)为试材,研究根系分泌物对西瓜种子萌发及西瓜幼苗根系活力的影响.结果表明:抗病品种根系分泌物对自身种子的萌发、幼苗的根系活力有促进作用,感病品种根系分泌物对自身种子的萌发、幼苗的根系活力有抑制作用,葫芦砧木自根苗根系分泌物对抗、感品种种子的萌发、幼苗的根系活力均有抑制作用,南瓜砧木嫁接苗、自根苗根系分泌物对抗、感病品种的种子萌发、幼苗的根系活力均有显著的促进作用. 相似文献
13.
Plants in living walls face challenges from intraspecific and interspecific competition from plants around them, as well as water and nutrient availability in the growing media. This paper explores these challenges using four different species of hardy perennials.Campanula poscharskyana ‘Stella’, Geranium sanguineum ‘Max Frei’, Sesleria heufleriana and Veronica officinalis ‘Allgrün’ were grown in two types of vertical growing media, made of either coir or stone wool, in transparent boxes under greenhouse conditions. In the media, plants were placed above each other, two plants of same species, two plants of different species, or a plant grown alone. Root frequency was registered over 56 days and the activity of individual root systems was studied through uptake of 15N. In addition, plant dry weight and N content as well as water content in the growing media were measured at cessation of the experiment.Shoot and root growth as well as nutrient content in plants were higher in coir than in stone wool and plants placed at the top position had significantly higher biomass than at the bottom position. The stone wool media had significantly higher water content in the lower part of the media while the coir media had water more evenly distributed. Species differences in root frequency were found. Campanula and Geranium showed strong root growth and had root frequencies of up to 0.9, whereas Sesleria and Veronica had less root growth, in some cases only root frequencies around 0.3. The species reacted differently to root competition and planting position and there were differences in the competitive ability between the species. Campanula and Geranium were not affected by competition, whereas both Veronica and Sesleria showed altered root growth due to competition depending on the growing medium. When Geranium was grown above Veronica in stone wool, plant biomass and 15N uptake increased in Veronica indicating environmental modification, with one species improving the growing conditions for another.The results revealed that growing plants vertically in a living wall is complex, and that choice of growing medium and species composition is important for a successful living wall. Planting combinations should therefore be tested before being used in commercial applications. 相似文献
14.
Manually measuring tree root characteristics can be inefficient and limiting. To test the application of a new digital technology in tree root architecture research, root systems from 29 green ash (Fraxinus pennsylvanica 'Patmore') trees were unearthed, cleaned, and photographed to create 3D models using structure from motion (SfM) photogrammetry. Three root segments from each root system were selected, marked, and removed after being photographed. The volumes of these segments (derived from the 3D models) were compared against volumes measured using water displacement. In addition to the root segments, model and water displacement volumes were compared for three complete root systems. Regression analysis showed a strong linear relation between the two volumes measurements (adjusted R2 = 0.97 for the root segment data). The RMSE for the root segment volume estimates was 40.37 cm3 (12.3%), with a bias of 17.2 cm3 (5.3%). This error rate was similar to previous published work and suggests the technology used may allow researchers to improve efficiency in data capture, add new measurements (i.e., surface area) to their modeling efforts, and digitally preserve tree root systems for future study. 相似文献
15.
西瓜化感作用及其化感物质成分分析 总被引：1，自引：0，他引：1
以早佳84-24为试材,研究了西瓜根、茎叶以及根系分泌物的化感效应,并对西瓜根、茎叶和根系分泌物中的化感物质进行了GC-MS检测。结果表明：西瓜根、茎叶水浸提液浓度为2.5 g?L-1时,促进西瓜种子发芽和幼苗生长|在浓度大于5.0 g?L-1时,表现为抑制作用,且随着浓度的增加,抑制作用增强|同一浓度时,西瓜茎叶水浸提液对西瓜种子发芽和幼苗生长的抑制作用大于根系水浸提液。西瓜根系分泌物浓度在2.5 μL?L-1时,促进西瓜种子发芽和幼苗生长|浓度为5.0 μL?L-1时,也开始表现为抑制作用。表明西瓜根、茎叶和根系分泌物对西瓜种子发芽和幼苗生长均呈现出低促高抑的规律。在西瓜根、茎叶和根系分泌物中共检测出32种化学物质,其中酯类化学物质最多,有14种|在西瓜根中检测到14种化学物质,茎叶中检测到19种,根系分泌物中检测到22种,其中一些曾被报道为化感物质,说明西瓜不同组织中化感物质的种类与含量不同,化感作用强度也不同。 相似文献
16.
The root extension rate of Betula pendula, transplanted at two phenological stages, was studied in a Nordic climate. Landscape-size trees were transplanted from the field into root-study boxes (rhizotron) in early and late spring of 1999 and 2000. In early spring, 6 trees were transplanted when the leaves had just started to unfold; likewise, in late spring, six trees were transplanted when the leaves were fully unfolded and the shoot extension was in progress. Root growth was recorded during the first post-transplant season and the tree roots were finally excavated. Results indicate that the root extension rate of B. pendula follows seasonal soil temperature. The mean root extension rates at ten days intervals varied from 4 to 11 mm/day with a total average for the growing season of 7 mm/day in 1999 and varied from 4 to 9 mm/day with a total average for the growing season of 4 mm/day for 2000. The average length of new roots was 89 cm and there was no significant difference in length, dry weight or number of new roots between the two transplant times. It appears, therefore, that the phenological stage at transplanting during the period from bud break to fully developed leaves has minor effect on landscape establishment of B. pendula, when an adequate amount of water is provided. 相似文献
17.
We conducted two experiments to evaluate the impact of cultural treatments on growth and establishment of container-grown London planetrees (Platanus × acerifolia’ Bloodgood’). In both experiments, 48 trees grown in 100 l (#25) black plastic containers were assigned at random to one of three root-ball treatments prior to planting; no treatment (Control), outer 3 cm of roots removed around entire root-ball (Shave), or outer circling roots disentangled from the root-ball (Tease). In Experiment 1, half of the trees were fertilized with 400 g of controlled release fertilizer (15-9-12; N-P2O5-K2O) at planting and the remainder of the trees were not fertilized. In Experiment 2, half of the trees were mulched with an 8 cm deep × 2 m diameter ring of coarse ground pine bark at planting and the remainder of the trees were not mulched. In Experiment 1, fertilization at planting increased SPAD chlorophyll content on two of four measurement dates but did not affect cumulative height or caliper growth after two years. After two growing seasons, root-ball treatments (shaving or teasing) increased root growth outside the original root-ball compared to control trees. Both root-ball treatments also reduced circling roots. In Experiment 2, mulching at planting increased soil moisture and cumulative tree height and diameter growth. Shaving increased new root growth and both root-ball treatments improved root architecture and reduced circling roots. Overall, the study demonstrates that root-ball manipulations can stimulate new root growth and reduce circling roots. Mulch is a valuable aid to conserve soil moisture and increase tree growth. Fertilization at planting provided little benefit in this experiment, which may have been related to a high level of soil fertility at the site or nutrient loading of the trees from nursery culture prior to transplanting. 相似文献
18.
本文以番茄为例,研究同一品种,不同处理方法对番茄根结线虫的影响,并进而以植株不同生育时期的生长情况研究了不同处理条件下,根结线虫对植株危害的区别,同时为生产中根结线虫的防治提供理论依据,为绿色蔬菜生产提供有效的防治措施。 相似文献
19.