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1.
B. Ehdaie  J.G. Waines 《Euphytica》1997,96(3):363-375
Little is known of genes that influence root development and drought resistance in bread wheat. The evapotranspiration efficiency (ETE = ratio of vegetative dry weight to total water used) of spring bread wheat tall landrace ‘Chinese Spring’ is relatively high. We used 42 ditelosomic and dimonotelosomic lines of Chinese Spring to identify chromosome arms that influence plant characters and ETE. Multiple regression analyses indicated that 96% of the variation observed in ETE was explained by variation in vegetative dry weight and total water used. Variation in plant height, number of spikes (tillers), root dry weight and shoot dry weight (excluding grains) together explained 88% of the variation observed in plant vegetative dry weight. Chromosome arms involved in expression of days to heading and maturity, plant height, number of spikes, root dry weight, shoot dry weight, number of grains, grain weight, and carbon isotope discrimination (Δ) were identified. Specifically, both arms of chromosome 2A, the long arm of chromosome 2B, and the short arm of chromosome 2D might carry genes with positive effects on number of spikes, root dry weight, and shoot dry weight. None of the aneuploids produced grain yield greater than Chinese Spring. The short arms of chromosomes 6A and 4D might carry genes that suppress Δ. Chromosome 1D might carry genes that increase relative water loss. The chromosome arms belonging to homoeologous group 2 might carry genes with positive effects on ETE. The genetic basis of ETE in modern wheats could be broadened by substituting specific chromosome arms of landrace wheats carrying desired characters into their genomes. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

2.
Water stress was imposed by cessation of watering (CW) on bread wheats and, in some experiments two spelt wheats, during 9–17 days, starting at the 4–5 leaves stage. Main shoot foliar stages (MSS) were delayed by CW and the effect remained thereafter.
The presence of side tillers (intact or partly destroyed by heat or potassium iodide (KI) was not beneficial to main shoot foliar development after the end of CW. Emergence of tillers after the onset of CW was also delayed, but the effect was small if timing was expressed in MSS. Secondary tillers were the most sensitive to water shortage, their number, size and foliar stage were drastically reduced.
The two cultivars of spelt wheats were not less sensitive to CW than the bread wheat tested.  相似文献   

3.
Investigations about the yield formation of Winter Wheat Cultivars with Short and Long Straw.
The yield formation of winter wheat cvs with semi-dwarf, short straw and long straw growth habit was investigated over three years in field and glasshouse trials.
The cv with semi-dwarf growth habit had less earbearing tillers and spikelets per ear, an essential lower reduction rate of spikelets and more kernels per spikelet. This cv ranged medium in thousand kernel weight (tkw). Cvs with short straw differed from cvs with long straw through a lower reduction rate of tillers and a lower tkw.
No differences were found in the time of development of generative organs in specific growth phases. Cvs with short straw had advantages in assimilation by means of higher leaf area indices from tiller formation till anthesis and a better light penetration in the canopy due to a more erect leaf orientation. These characters may have been decisive for the higher survival of tillers. The cvs with a long straw however had a higher tkw, properly due to a less compact ear and a higher assimilate gain during kernel filling. Only small differences were found in root growth in favour of the cvs with short straw. The semi-dwarf cv had the shortest roots. The cv "Kanzler" with a long straw had the best drought resistance.  相似文献   

4.
晚播冬小麦各叶位叶片14C同化物的运转分配   总被引:3,自引:0,他引:3  
王振林  尹燕枰 《作物学报》1995,21(3):263-270
采用^14CO2标记方法研究了晚播小麦各叶位叶片同化物质的运转配变化,研究表明,晚播小麦不同叶位叶片的^14C同化物向植株各部位的分配具有明显的分工,据此将晚播小麦主茎叶片分组,基部叶组即晚播小麦冬前及冬季出生的叶片(1-4叶),其同化物主要供给新生叶、根系、部分供给分蘖;中部叶组指返青至拔节期出生的叶片(5-8叶),其同化物主要供给叶片、茎秆和分蘖;拔节后出生的叶片为上部叶组(9-10叶)。上部  相似文献   

5.
The intra-varietal variation of plants of Irish and S. 23 perennial ryegrass (Lolium perenne) growing in nutrient solution was studied in separate experiments.The variation in shoot growth was due to differences in both the rate of production and size of the tillers, while in root growth it was related to the size of individual roots. Root relative to shoot growth was also related to the size of the individual roots.In both varieties the frequency-distribution of size of individual roots and rate of root growth compared with shoot growth was positively skew. Root characters were more variable than shoot characters. The results are discussed in relation to possible selection pressures and morphology.  相似文献   

6.
Spring cereals are commonly sown at high rates in Finland with the result that, under long day conditions, tillering is suppressed. If the apical dominance maintained by the shoot apex can be broken through altered crop management the possibility exists that the increased tillering allows a reduction in seeding rate. The objective of our study was to assess the effects of mechanical and chemical treatments, aimed at breaking the uniculm growth habit, on changes in green leaf area and consequently on biomass accumulation and partitioning in two spring oat, two spring barley, and two spring wheat cultivars. Results indicated that single applications of gibberellic acid (GA3), chlormequat chloride (CCC), and urea had no overall, persistent, advantageous effect on crop growth, even though occasional, temporary increases in LAI, and accumulation and partitioning of biomass, were recorded. Changes in crop structure, however, did not solely result from the increased contribution of tillers; treatments also accelerated main shoot growth. Following damage to the main shoot caused by mechanical treatments in particular, one of the tillers rapidly replaced the main shoot. Therefore, a low seeding rate associated with treatments aiming at breaking apical dominance cannot substitute for a high seeding rate at high latitudes. This was particularly the case in 1992 when early summer drought—prevalent in southern Finland - resulted in peak values of LAI as low as ≤ 2 for wheat and ≤ 3 for oats and barley.  相似文献   

7.
CHA 杂种小麦生育特点及农艺因子调控效应研究   总被引:4,自引:0,他引:4  
张艳敏  李晋生 《作物学报》1998,24(6):990-996
1991-1994年度对杂种小麦叶蘖生长,根系生育,分蘖成穗,幼穗分化,籽粒灌浆,干物质积累分配等的系统深入研究结果表明,CHA杂种有诸多方面的优势;分蘖发生相对较早,且根多蘖壮,与主茎差距小,成穗相对较整齐;初生根生长快,扎得深,次生根条数多且根系粗壮,根干重及深层根比率高,生理活性强,籽粒灌浆快,增期早,强度大,持纽时间长,粒重优势突出;播期,密度,供水等农艺措施对根,茎,叶蘖的生长,干物质积  相似文献   

8.
Slow leaf formation in spring is regarded as the main factor limiting sugar beet yield. It is therefore expected that yield can be enhanced when plants develop leaves earlier resulting in an extended growing period. The aim of this study was to analyse leaf and storage root growth of sugar beet plants sown in autumn or very early in spring with regard to possible yield increases. In 2005/06 and 2006/07, field trials were conducted at 4 sites with 6 sowing dates: August, beginning and mid of September, and in February, March and April. Sequential harvests were conducted to follow yield formation.Field emergence of autumn sown sugar beets was fast and reached 90% whereas in early spring it was severely restricted due to low temperature. Leaf and root yield formation of autumn and spring sown sugar beets could well be described with thermal time confirming that sugar beet growth is temperature driven and day length insensitive. Despite longer growing periods autumn sown beets did not form more cambium rings in the storage root than spring sown beets. That might be partly due to the bolting process after winter. However, early spring sown beets as well did not achieve more cambium rings than plants sown in April pointing to a presumably limited ability to adapt cambium ring formation. Because of the shift to reproductive growth, autumn sown beets formed high amounts of shoot dry matter, but not much root dry matter. Furthermore, the root dry matter consisted of a lower sugar and a higher marc content and would therefore not be suitable for sugar recovery. Earlier sowing in spring did not result in a significant yield increase because the benefit from early sowing diminished throughout the season as also obvious from the distance between the cambium rings.For bolting resistant sugar beet varieties, which are expected to be available in near future, the presented data form a basis to predict yield with models. However, it has to be investigated to what extent sugar beet growth and yield formation benefits from early sowing and extended growing periods.  相似文献   

9.
The photosynthesis, shoot formation, leaf area development and dry matter production were examined in control and de-eared plants of T. monococcum var. G 1372and T. aestivum var. Sonalika. The removal of ears decreased the diurnal maintenance of photosynthesis and consequently, the dry matter production in Sonalika but not in G 1372. There was a considerable growth of alternative sinks such as shoots and roots when ear sinks were removed. This alternative sink capacity of de-eared plants seemed to have compensated for limited sink demand of ears in G 1372but could not entirely compensate for the more efficient grain sink in Sonalika. The diploid wheat produced more dry matter than the hexaploid wheat in the pre-ear emergence period and less in the post-ear emergence period. In the preear emergence period, the difference in dry matter appeared to be mostly because of the difference in duration to ear emergence. During the post-ear emergence period, the lower dry matter in G 1372seemed to be owing to a rapid decrease in photosynthesis rate after anthesis because of the lower sink capacity of its grains.  相似文献   

10.
Effect of monoethanolamine on yield of crops
I. Studies on the effect of monoethanolamine on the grain yield and the nitrogen household in cereal plants (pot experiments)
The effect of monoethanolamine (EA, applied as foliar spray, 10 mg per pot) on grain yield and yield components was investigated in pot experiments with spring barley, winter wheat, and winter rye. Under conditions of a moderate drought stress the applied EA increased the grain yield of spring barley from 5 % to 7 % (significance only at α= 0.05). A stimulating effect of EA on the grain yield of winter wheat and winter rye was also obtained.
The positive influence of EA on the grain yield of spring barley was reproducible under the conditions of a limited water supply in small-scale plot experiments (increase of yield about 9 %).
In case of spring barley and winter rye the increase of the grain yield by EA, applied at growth stage 31 (= DC 31) was connected with a greater number of ear-bearing tillers. The increase of the winter wheat yield resulted from more grains per ear of the tillers.
The enhanced formation of tiller grain mass and total tiller biomass by EA was in correlation with a higher nitrogen import into tillers (r = 0.8+). Since an export of N from the main shoots into the tillers was not observed a higher N uptake (≥ 6 %) was calculated from N balances. After a fertilization with 15N-labelled fertilizers the additional 15N uptake was 13 % to 20 %.
Possible stress reducing activities caused by EA are discussed.  相似文献   

11.
不同播期与基本苗对小麦生长发育及产量构成的影响   总被引:1,自引:2,他引:1  
为探明稻麦周年生产条件下小麦种植适宜播期和基本苗组合,于2012—2014 年在江苏省沭阳县进行了播期和基本苗组合试验,研究了不同播期(10 月10 日、10 月17 日、10 月24 日、10 月31 日和11 月7日、11 月14 日)和基本苗(180 万/hm2、270 万/hm2、360 万/hm2、450 万/hm2、540 万/hm2)条件下小麦生长发育及产量构成。结果表明,出苗率主要受播期影响,迟播降低明显;随着播期推迟小麦叶龄逐渐变小,全生育期缩短,缩短天数少于播期推迟天数。基本苗处理对出苗率和叶龄影响不大。相同生育阶段,同一播期随着基本苗的增加茎蘖总数增多,相同基本苗处理随着播期的推迟茎蘖总数减少。播期对小麦株高、穗下节间以及穗长影响明显。单产随着播期推迟先升后降,不同播期和基本苗处理对产量构成影响显著或极显著。因此,淮北地区稻茬麦遇冷冬适宜播期在10 月17—24 日,遇暖冬适宜播期在10 月17—31日,最佳基本苗360万/hm2。  相似文献   

12.
Field trials were conducted with autumn- and spring-sown faba beans in Northern Germany during four seasons to examine the expected preceding development of autumn-sown plants, its possible transformation into a higher yield potential and its dependence on sowing dates and varieties. Height, appearance of leaves, inflorescences, mature flowers, potential and actual pot set was rated weekly, and flower initiation and tillering occasionally. Comparison was made for one winter type sown in autumn and spring, and between 6 winter types and 3 spring types, in two seasons each.
Development of autumn-sown plants significantly preceded that of spring-sown in each year, regardless of the plant material used. The mean advance, diminished considerably with time due to prolonged developmental phases in autumn-sown plants which, however, did not improve vegetative, generative or reproductive potentials of main tillers. Potentials formed by the six winter types, interacted strongly with the seasons, at least in part due to changing plant densities. Thus, only a very few traits appeared typical: a short stature with few leaves for Avrissot and the opposite for Bourdon , a high number of ripening pods for Avrissot and a low number for Banner . Early compared to late sowing in autumn increased the number of leaves, and in one year even the number of mature flowers and ripening pods per tiller, but values of early sowing never exceeded those of spring sowing. Enhancement of tiller formation by early compared to late sowing diminished after spring; nevertheless about two reproductive tillers per plant in autumn-sown stands always led to a higher density of tillers than in spring-sown.  相似文献   

13.
Certain apical developmental stages have been shown to be of value in guiding management practices or indicating sensitivity to stresses. Because the determination of apex development, however, requires a high degree of skill, the use of external macromorphological growth parameters of spring wheat ( Triticum aestivum L.) to predict apex developmental stage was examined in this study. The growing degree days (GDD), growth period on days (DAY), number of leaves, number of surviving tillers, height of uppermost node, height of uppermost stipule and the length of ear primordium were used as growth parameters. Field trials were carried out as plot trials and on-farm trials in 1989-91. The growth parameters of three spring wheat cultivars and their ear developmental stages were determined at 2-3 day intervals after emergence to pollination in the plot trials. The relationship between the development of the ear and the growth parameters of each cultivar was studied using polynomial regression up to 3rd degree and stepwise regression analysis. The accuracy of the mathematical functions were tested against independent data determined from the farm trials. To get a reliable estimate of the apex developmental stage, DAY and GDD were found to be the most useful parameters. Furthermore, the growing time (maturation class) of a cultivar should be taken into a consideration.  相似文献   

14.
在土培条件下,以对1,2,4-三氯苯(TCB)敏感性显著差异的宁粳1号(敏感)和扬辐粳8号(耐性)为对象,研究了不同浓度1,2,4-三氯苯(TCB)胁迫对两种水稻分蘖盛期生长和生理特性的影响。结果表明,不同浓度TCB胁迫下,敏感基因型宁粳1号最长根长、株高、单穴分蘖数、地上部和地下部干物重随胁迫程度加深均显著递减; 耐性基因型扬辐粳8号在低浓度(20 mg kg-1) TCB胁迫下,最长根长、地上部和地下部干物重极显著增加,当中高浓度(40 mg kg-1、60 mg kg-1) TCB胁迫时,最长根长、株高、单穴分蘖数、地上部和地下部干物重显著下降。不同浓度TCB胁迫下,敏感基因型宁粳1号根系活力、叶绿素含量、叶片和根系可溶性蛋白质含量相对较低,叶片和根系超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性明显降低,O2?产生速率和丙二醛(MDA)含量显著增高; 耐性基因型扬辐粳8号在低浓度(20 mg kg-1) TCB胁迫下,根系活力、叶片和根系的可溶性蛋白含量、SOD、POD、CAT活性极显著增加,O2?产生速率和MDA含量极显著降低,当中等浓度(40 mg kg-1) TCB胁迫时,SOD、POD、CAT活性虽然增强,但O2?产生速率显著增加,MDA大量积累,当高浓度(60 mg kg-1) TCB胁迫时,其根系活力、叶绿素含量极显著降低,根系中SOD、CAT活性显著降低,O2?产生速率和MDA含量显著增加。总之,低浓度TCB胁迫下,长势良好、叶片和根系可溶性蛋白质含量高、抗氧化系统清除活性氧能力强、膜脂过氧化程度低是耐性基因型扬辐粳8号区别于敏感型宁粳1号的主要特征。  相似文献   

15.
The identification of genotypes having potential salt tolerance is an effective approach to solve the problems of saline soils.
Seed germination and seedling establishment are limiting factors in crop production. Seven wheat ( Triticum aestivum L.) and one Triticale (X Triticosecale Wittmak) genotypes were evaluated for salt tolerance at emergence and early seedling growth in solution culture with NaCl salinities up to 300 mM L−1 (electrical conductivity equals 27.6 dS m−1).
Seedling emergence was delayed by increasing NaCl in nutrient media. At 200 mM L−1 NaCl, the emergence percentages of wheat genotypes ranged between 68.7 % and 91.3 % after 7 days and 79.3 % and 98.7 % after 15 days. While at 300 mM L−1, the emergence percentages of the wheat genotypes were 0.0 % after 7 days. After 15 days the emergence percent ranged between 24 % and 72 %. The emergence percent of the Triticale line was 88.7 after 7 days and 89.3 after 15 days at 200 mM L−1, while it was 25.3 % and 84 % after 7 and 15 days, at 300 mM L−1, respectively. Root and shoot dry weight were greatly reduced by increasing NaCl, however, the Triticale line showed less reduction in growth compared to the wheat genotypes. K+, Ca2+ and Mg2+ were decreased with increasing salinity levels while Na+ content was decreased in the shoot tissues of wheat and Triticale genotypes.  相似文献   

16.
Root growth of seedlings of old and new winter wheat cultivars and a spelt wheat at varying levels of nitrogen
Root growth of five old (time period 1882–1920) and five new (time period 1975–1982) winter wheal cultivars and a spelt winter wheat cultivar was investigated in two greenhouse trials. Nitrogen (NH4NO3) was supplied at six (Exp. I) and two (Exp. II) levels (sub- to supraoptimal for shoot growth). The seedlings were grown in sand-filled polyethylene tubes of 4.5 cm diameter and 50 cm length at 20 oC. The plants were harvested 11 (Exp. I) and 12 (Exp. II) days after emergence. At this early stage of development root growth o: old and new cultivars differed only slightly. The old T. aestivum cultivars had more seminal roots. The longest roots of the modern cultivars penetrated into deeper layers of the substrate. For some traits, cultivar: seemed to respond specifically to the varying N-supply. However, there were no significant difference: between old and new cultivars. Neither were old cultivars better adapted to low N-fertilization nor were modern cultivars superior in tolerating toxic concentrations of NH4NO3. Increasing N supply changes root growth as follows: decline in root dry matter, increase in shoot/root ratio of dry weight, decrease in number of seminal roots, shortening of axes and more laterals, increase in diameter of the laterals and less significantly of the main roots, increase in density of laterals, decline in root surface area. The number of apices was affected only to a very small degree.  相似文献   

17.
采用石英砂培养方法并去除或保留分蘖,研究了旗叶期缺磷对大穗型小麦CA9325和多穗型晋麦2号(JM2)生长后期旗叶光合和蒸腾速率、干物质和磷在体内分配以及最终产量的影响。结果表明: ⑴旗叶期缺磷一段时间后降低小麦旗叶的光合和蒸腾速率。不同供磷水平下,去蘖使小麦旗叶光合和蒸腾速率大都高于同期未去蘖的;⑵旗叶期缺磷几乎导致两品种所有器官和整株干物质和磷的积累降低,去蘖的小麦籽粒干物质和磷总量占整株的比例均高于未去蘖的,说明缺磷促进小麦各营养器官的磷向籽粒转移;⑶主茎干物质和磷的积累以CA9325高于JM2,而JM2则以分蘖占优势,这与JM2分蘖数较多有关;⑷ 不论供磷还是缺磷,未去蘖的CA9325籽粒产量低于JM2,而去蘖后则相反。不同库容量的CA9325千粒重和籽粒磷含量均高于JM2。全生育期供磷条件下的磷吸收效率,以未去蘖的CA9325显著高于JM2,去蘖后两品种间无明显差异。  相似文献   

18.
Abstract The objective was to study soil water conservation and physiological growth of wheat (Triticum aestivum L.) using composted cattle manure applied either as mulch or incorporated with soil at 20 Mg ha?1. Haruhikari, a relatively drought‐sensitive and Hongmangmai, a relatively drought‐tolerant wheat, were the cultivars studied under both adequate and deficit irrigation. Fourteen weeks after sowing (WAS), the number of tillers and leaves was significantly reduced by 19 % and 30 % respectively under deficit irrigation and Hongmangmai produced slightly (10 %) more tillers than Haruhikari. Unlike mulching, the incorporation of manure had favourable effects on plants in terms of shoot dry mass (SDM) by 36 % and number of tillers and leaves by 40 %. Haruhikari produced substantially (29 %) greater root mass under adequate irrigation but Hongmangmai produced slightly (2.7 %) more roots and responded much better to manure use whether under adequate or deficit irrigation. As a result, Hongmangmai suffered less severe reductions in tillers and biomass under water stress. In comparison, the mulched manure treatment saved 15 % and 64 % respectively more water than the control and the treatment incorporating manure, but this advantage in water‐saving did not translate to superior plant growth. Leaf water potential (ψl) under adequate irrigation significantly exceeded that under deficit irrigation by 27 % and the ψl of Haruhikari exceeded that of Hongmangmai by 15 %. However, Hongmangmai may be considered more tolerant of dehydration since it maintained much higher net photosynthetic rates (PN) even with a lower leaf water potential. The reduction in the PN and intracellular carbon dioxide concentration (Ci) of the cultivars under deficit irrigation was on account of decreasing stomatal conductance (gs) and transpiration rate but on average, the gs of Hongmangmai significantly exceeded that of Haruhikari by as much as 0.53 under adequate irrigation and 0.22 under deficit irrigation. In conclusion, we suggest that the drought tolerance of Hongmangmai was related to its superior root growth and greater ability than Haruhikari, to efficiently utilize incorporated manure for growth under water stress.  相似文献   

19.
Shoot- and full-competition between first-year seedlings of meadow fescue (Festuca pratensis Huds.) and timothy (Phleum pratense L.) was studied m two separate experiments in a greenhouse. Timothy had a higher competitive ability than meadow fescue and produced more tillers, had a higher shoot weight and a larger leaf area in all strata of the canopy.
Competition for light was important up to the first harvest. The upright growth form of timothy plants during the reproductive phase enabled them to shade the unvernalized and prostrately-growing meadow fescue. Root competition may have been important afterwards. After the first harvest, tiller formation in timothy plants was high, and significantly enhanced when grown with meadow fescue. Meadow fescue produced few new tillers, and its tiller formation was depressed when competing with timothy.  相似文献   

20.
3种盐胁迫对小麦苗期生长的影响   总被引:13,自引:2,他引:11  
为探讨土壤盐分含量与小麦生长的关系,选用永良4号,通过盆栽试验,研究了在不同盐分离子种类NaCl,Na2SO4,NaCl Na2SO4,7个盐分水平(0.1%,0.2%,0.3%,0.4%,0.5%,0.6%,0.7%)条件下小麦苗期的生长情况。结果表明,随着土壤盐浓度的升高,小麦的出苗率、株高均有所下降。NaCl对小麦的胁迫作用最大,NaCl Na2SO4次之,Na2SO4最小。低浓度盐胁迫对小麦根的生长有一定的刺激作用,但随着盐浓度的增加,盐分对根的生长产生了抑制作用,但作用均比较小,并且与地上部分相反。试验结果将对盐渍化耕地小麦生产有重要的参考价值。  相似文献   

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