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991.
The survey and progress about the study applying mechanics to traditional botany are summarized. It gives brief analysis to the influence of plant growth and development under the mechanics factors, such as mechanical vibration, strong sound wave (or ultrasonic wave), electromagnetic field and microgravity, et al. In other word, the biological effects of plant caused by environmental stress stimulation are set out (They contain positive effects and negative effects). Furthermore, the profound biological effects and some possible mechanism of the plant tissue and cell are discussed. The paper put forward several main problems about botanical mechanics which must be researched at the beginning of 21st century, and the more significant thing about it is the operation of Ca 2+ which as a Second Messenger, will be probed into. At the end of the paper, the well development tendency and practical prospect of the newly compound subject _botanical mechanics is also presented. 相似文献
992.
X.Y. Zhang H.M. Ge G.X. You C.Y. Hao L.F. Wang Y.S. Dong Y.P. Tong B. Li Z.S. Li 《分子植物育种》2007,5(2):225-226
Besides the natural selection, the crops cultivated today have experienced two episodes of strong artificial selection, domestic and modem breeding. Domestication led to giant genetic structure differentiation between cultivars and their wild species, while modem breeding made further genetic structure differentiation between the modem varieties and the landraces. In a population, diversity of the loci under strong selection is significantly lower than that of other loci. At the same time, diversity in the genomic regions flanking these selected loci also declines in the process of selection. This phenomenon is called hitchhiking effects or selection sweep in genetics (Andolfatto, 2001). 相似文献
993.
Summary The colour variation between several gerbera cultivars were analyzed with a tristimulus colorimeter. A pilot study with a few cultivars showed that the flower colour variation between cultivars and colour effects during the growing season can be calculated quantitatively on the basis of data measured by the colorimeter. On the basis of these results the colour differences between a larger group of gerbera cultivars were measured. A consistent number of cultivars was distinct on the basis of colorimetric data and visual colour assessments.Abbreviations CIE
Commission Internationale de l'Eclairage
- PBR
Plant Breeders' Rights
- R.H.S.
Royal Horticultural Socicty
- UPOV
Union for the Protection of New Varieties of Plants 相似文献
994.
Effect of bunt infection on the frost resistance of wheat varieties and of lines containing Bt genes
In artificial infection experiments carried out in the nursery in Martonvásár in 1991, 1992 and 1993, studies were made on the bunt infection of wheat varieties bred in Martonvásár and of monogenic lines containing known resistance genes (Bll to Btl0, respectively). This was followed in 1993 by tests on the frost resistance of healthy wheat seedlings and wheat seedlings artificially infected with bunt in the frost-testing chamber of the Martonvásár phytotron. During the period of the experiment, the local pathogen population was avirulent to genes Bt9 and Btl0, and virulent to Bt7. Monogeniclines containing resistance genes Bt4, Bt5, Bt6 and Bt8 had good resistance, while that of lines containing Bt1, Bt2 and Bt3 was only moderate. Among the cultivated varieties, only three proved to be moderately resistant (Martonvásári 17′,‘Martonvásári 23′,‘Fatima 2′), while the remainder were susceptible or very susceptible. The frost resistance of plants infected with bunt was significantly lower, over an average of the varieties, than that of healthy plants. A close (r = 0.890) correlation was found between the bunt susceptibility of the varieties tested and the increase in frost kill due to infection, while no correlation was observed in this respect for monogenic lines containing various resistance genes (Bt). 相似文献
995.
H.C. Sharma 《Euphytica》2001,122(2):391-395
Sorghum midge, Stenodiplosis (Contarinia) sorghicola (Coquillett), is an important pest of grain sorghum, and host plant resistance is an important aspect of control of this
pest. This research investigated how cytoplasmic male-sterility and source of pollen influence the expression of resistance
to sorghum midge. Sorghum midge emergence was significantly lower in panicles of midge-resistant and midge-susceptible cytoplasmic
male-sterile lines when pollinated with AF 28 - a midge-resistant restorer line, than those pollinated with Swarna - a midge
susceptible restorer line, indicating the presence of xenia effects. Maintainer lines (B-lines) of midge-resistant parents
had significantly lower numbers of eggs and larvae than the B-lines of midge-susceptible parents. Male-sterile lines of the
both midge-resistant and midge-susceptible lines were equally susceptible, indicating that resistance to sorghum midge is
influenced by factors in the cytoplasm of the B-line. These findings will have an important bearing on the production of hybrids
with resistance to insects.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
996.
Identifying AFLP and microsatellite markers for vernalization response gene Vrn-B1 in hexaploid wheat using reciprocal mapping populations 总被引:5,自引:0,他引:5
Marker‐assisted selection may be useful for combining specific vernalization response (Vrn) alleles into a single wheat genotype for yield enhancement; however, DNA markers are only available for two of the three genes identified to date. The objectives of this study were to investigate reciprocal effects on days to heading using F2 populations generated by cross‐hybridizing near‐isogenic lines (NILs) carrying spring (Vrn‐B1; TDB) and winter (vrn‐B1; TDC) alleles, and to identify markers linked to Vrn‐B1 through genetic linkage analysis. Heading data were recorded for 91 and 89 progeny from reciprocal mapping populations TDB/TDC and TDC/TDB, respectively, and significant (P < 0.0001) reciprocal and dominance effects were detected. Among 207 amplified fragment length polymorphisms primer pairs and seven wheat microsatellite markers screened, two and one, respectively, were linked distally to Vrn‐B1 on wheat chromosome 5BL. Microsatellite Xgwm408 was most closely linked to Vrn‐B1 at 3.9 and 1.1 cM in the TDB/TDC and TDC/TDB map, respectively. Reciprocal differences in recombination distances emphasize the importance of female parent choice when generating mapping populations. Molecular markers are now available for three Vrn loci in wheat. 相似文献
997.
Genetics of resistance to Sesamia inferens infestation and its correlation with yield in maize 下载免费PDF全文
Javaji C. Sekhar Chikkappa G. Karjagi Bhupender Kumar Sujay Rakshit Lakshmi Soujanya Pradyumn Kumar Krishan P. Singh Appavoo Dhandapani Sain Dass Ramanujam S. Kumar 《Plant Breeding》2015,134(4):394-399
Sesamia inferens (Walker) causes 25.7–78.9% losses in maize production in South and South‐East Asia. The genetic basis of host plant resistance is the prerequisite for resistance breeding. Twenty‐four populations derived from S. inferens resistant × susceptible inbreds were used to study the genetic regulation of resistance to S. inferens in maize, to determine the importance of genetic effects through generation mean analysis (GMA) and to understand correlation between resistance and yield. Resistant and susceptible inbreds differed significantly in leaf and stem injury ratings (LSIR), a measure of host plant resistance. Mean LSIR range among resistant and susceptible parents was 2.15–2.55 and 7.83–8.22, respectively. The broad‐sense heritability ranged from 0.40 to 0.71, and the mean number of effective factors ranged from 1.9 to 2.6. The resistance against S. inferens was largely governed by additive × additive (i), followed by dominance (d) and additive (a) gene effects. Significant negative correlation (?0.27 to ?0.96) was observed between LSIR and yield. The findings suggest reciprocal recurrent selection for development of new inbreds with resistance followed by their involvement in hybrid development to exploit additive and non‐additive gene effects/variance. 相似文献
998.
M. Wetten T. Aasmundstad 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2020,69(1-2):101-108
ABSTRACTNorwegian Elkhound Grey is used for both leashed and non-leashed tracking. This study provides influence of fixed effects and estimates of genetic parameters of traits related to both types of tracks. In total, 5393 records from 1991 animals tested in the years 1995–2014 on lashed performance (5 traits), and 5405 records from 2070 animals tested in the years 2005–2014 on non-leashed performance (10 traits) were included in the dataset. The pedigree file contained 8623 animals. Heritabilities were generally low for the non-leashed traits and a bit higher for the leashed traits. Genetic correlations within trait group were very highly positive for the leashed dog traits, but variable among some traits in the non-leashed group. Genetic correlations between performance traits in the two groups were generally negative and unfavourable. Genetic trends were generally positive for the time periods. 相似文献
999.
为实现落叶再利用,筛选出有除草潜力且对土壤酶活性无抑制作用的绿化树种,开发经济环保的植物源除草剂,本研究通过室内盆栽试验研究10种绿化树落叶浸提液对狼尾草(Pennisetum alopecuroides)、黑麦草(Lolium perenne)、紫花苜蓿(Medicago sativa)、红三叶(Trifolium pratense)和麦仙翁(Agrostemma githago)5种草本植物的化感效应。结果表明:火炬树(Rhus typhina)落叶浸提液可抑制狼尾草、红三叶和麦仙翁(综合主成分值F为-0.81,-0.86,-0.87);青桐(Firmiana platanifolia)落叶浸提液可抑制紫花苜蓿、红三叶和麦仙翁(F为-1.17,-1.31,-1.69);栾树(Koelreteria interifolia)落叶浸提液可抑制紫花苜蓿、红三叶和麦仙翁(F为-0.48,-0.22,-0.22),且对土壤酶活性无综合抑制效应。因此,火炬树、青桐和栾树落叶浸提液可抑制3种以上化感受体且对土壤酶活性无综合抑制作用,有开发除草剂的潜力。 相似文献
1000.
《Veterinary anaesthesia and analgesia》2020,47(5):631-636
ObjectiveTo compare the effects of meloxicam or carprofen on glomerular filtration rate (GFR), and to evaluate the effect of meloxicam on urinary N-acetyl-β-D-glucosaminidase (NAG) activity, of cats after dental surgery.Study designRandomized, blinded, controlled trial.AnimalsA total of 24 mixed breed cats.MethodsCats were randomly assigned to one of three groups (n = 8 per group): meloxicam (0.2 mg kg–1); carprofen (4 mg kg–1); or saline (2 mL). Acepromazine (0.04 mg kg–1) and buprenorphine (0.02 mg kg–1) were administered intramuscularly as preanaesthetic medication. Test drugs were injected subcutaneously at the time of preanaesthetic medication. Anaesthesia was induced with intravenous propofol and maintained with isoflurane in oxygen. Mean arterial blood pressure (MAP), respiratory rate (fR), heart rate (HR) and haemoglobin oxygen saturation values (SpO2) were recorded. All cats underwent ultrasonic dental scaling with polishing. Teeth extraction involved mucosal flap creation, removal of alveolar bone and flap closure. Plasma iohexol clearance (ICL), a measure of GFR, was estimated before and 24 hours after anaesthesia induction in all cats. Urinary NAG index was estimated in saline and meloxicam groups at the same time points as GFR. Between-group and -time point differences in GFR and NAG index were compared using mixed model analyses. Data are presented as mean ± standard deviation (p < 0.05).ResultsThere was no significant difference in plasma ICL rate (range: from 1.22 ± 0.05 to 1.27 ± 0.04 mL kg minute–1) between groups or between time points. Urinary NAG index (range: from 1.0 ± 0.19 to 1.36 ± 0.29 Units gram–1) was not significantly different between meloxicam and saline groups. MAP, HR, fR and SpO2 did not differ significantly between groups.Conclusions and clinical relevanceMeloxicam and carprofen appeared to produce nonsignificant effects on GFR, and meloxicam did not affect the urinary NAG activity, of cats after dental surgery. 相似文献