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1.
1987~1988两年在杭州采用莲鞭扦插法代替传统的种藕繁殖,结果表明,莲鞭扦插具有下列优点:1.节约种藕.扩大繁殖系数.加速良种繁育.2.提高藕田复种指数,3.延长嫩藕上市时间.4.所结的藕体大小比较均匀,适宜作种藕. 相似文献
2.
细叶结缕草是一种优质草坪草种,引入杭州已有40多年历史.这种草不易给籽,一般不用有性方法繁殖,因而导致生活力衰退,无力与杂草竞争.本研究的目的在于改进繁殖技术,使退化的细叶结缕草更新复壮,缩短繁殖周期,由每年出圃一次增加为三次,生产出高质量的毯状草皮或草块.通过两年研究,已达到上述目的. 相似文献
3.
The aim was to study the effects of white clover cultivar and combinations with perennial ryegrass cultivars on seedling establishment in autumn‐sown swards and on winter survival of seedlings. Large‐leaved white clover cv. Alice and small‐leaved white clover cv. Gwenda, and an erect and a prostrate perennial ryegrass cultivar were sown in autumn in pure stands and as four binary grass‐clover mixtures. Mixtures of white clover cv. Huia and Aberherald with perennial ryegrass were also sown. Companion grasses had no significant impact on the establishment of white clover. The number of seedlings of white clover cv. Alice in mixtures (335 m?2) was higher than cv. Gwenda (183 m?2) and pure swards had similar white clover population densities as mixed swards. White clover cv. Huia tended to have more seedlings than Aberherald (355 and 205 m?2 respectively). No stolons were produced prior to a severe winter, because of the late sowing date. Winter survival of clover seedlings was 0·56 in mixtures and 0·69 in pure stands, irrespective of white clover or companion grass cultivar. Stolon development of white clover in autumn is often considered essential for overwintering survival and spring growth. In this study, there was considerable survival of the non‐stoloniferous tap‐rooted seedlings of all four clover cultivars despite a severe winter. 相似文献
4.
H. Ahokas 《Plant Breeding》1998,117(5):500-502
A method is described of inducing polyploids in detached stolons using an aqueous solution of colchicine, DMSO and glycerol. The donor plant remains uncontaminated and can be grown further to produce more stolons. The putative colchiploids can be chosen on a morphological basis and confirmed cytologically. About 10% of the treated stolons, starting with diploid and tetraploid strawberry, are converted, but 50% nonviability is caused by the treatment. The method can be applied to some other species and shoot types, using other chemicals with chromosome doubling or reducing effect, or even mutagens. The principle can be used without colchicine treatment to obtain strawberry plants from stolons without contamination of the soil around the main clone. 相似文献
5.
采用田间统计绿期法、电导率法和匍匐茎恢复生长法,对50份西南部野生狗牙根(Cynodon dactylon)和2份美国引进品种(Tifway和Tifeagle)进行耐寒性初步鉴定。结果表明:1)52份材料的绿期为277~306 d,Sau02033(越西)、Sau02040(自贡)的绿期最长;2)半致死温度(LT50)为-9.00^-1.72℃,Sau02014(金川)、Sau02040(自贡)的LT50最低;3)匍匐茎恢复生长率为18.05%~42.36%,Sau02012(金川)、Ly97021(遂宁)的恢复率最高;4)偏相关分析结果表明,其耐寒性与海拔显著正相关(P<0.05);5)将52份材料系统聚类分为A、B、C三类,耐寒性强弱表现为A>B>C,Tifway和Tifeagle被聚在C类,大部分野生材料的耐寒性高于这两个品种。综上可知,3种方法综合评定结果表明,Sau02040(自贡)、Sau02013(金川)、Sau02014(金川)、XZ2(察隅)耐寒性较强,具有良好的牧草和草坪草开发潜力,3种指标综合运用更能全面评价狗牙根的耐寒性。 相似文献
6.
7.
Akira Katoh Hiroki Ashida Ichiro Kasajima Shigeru Shigeoka Akiho Yokota 《Breeding Science》2015,65(1):77-84
The combined total annual yield of six major crops (maize, rice, wheat, cassava, soybean, and potato; Solanum tuberosum L.) amounts to 3.1 billion tons. In recent years, staple crops have begun to be used as substitutes for fossil fuel and feedstocks. The diversion of crop products to fuels and industrial feedstocks has become a concern in many countries because of competition for arable lands and increased food prices. These concerns are definitely justified; however, if plant biotechnology succeeds in increasing crop yields to double the current yields, it will be possible to divert the surplus to purposes other than food without detrimental effects. Maize, rice, wheat, and soybean bear their sink organs in the aerial parts of the plant, and potato in the underground parts. Plants with aerial storage organs cannot accumulate products beyond their capacity to support the weight of these organs. In contrast, potato has heavy storage organs that are supported by the soil. In this mini-review, we introduce strategies of intensifying potato productivity and discuss recent advances in this research area. 相似文献
8.
V. Pavl M. Hejcman† L. Pavl‡ J. Gaisler P. Hejcmanová-Neerkov᧠L. Meneses¶ 《Grass and Forage Science》2006,61(1):42-51
Changes in plant density were evaluated monthly in the first three vegetation seasons after imposing different grazing management treatments on abandoned semi‐natural grassland in the Czech Republic. There was no agricultural management in the 5 years before the start of the experiment in 1998. A completely randomized block experiment was established with the following five treatments: unmanaged control, intensive continuous grazing, extensive continuous grazing and a harvest in June followed by either intensive or extensive continuous grazing for the rest of the growing season. The sward was maintained at a target height of 5 and 10 cm under the intensive and extensive grazing managements respectively. An almost immediate increase in the densities of all sward components, especially grass tillers, occurred after the introduction of grazing on the previously abandoned grassland in comparison with the unmanaged control treatment. Trifolium repens was able to colonize and increase the number of its stolon growing‐points in all managed treatments, particularly in intensively grazed patches during the second and third experimental seasons. Delay to defoliation in both treatments containing a harvest in June resulted in an increase in the number of forb plants, particularly in the number of Taraxacum spp. plants, most probably due to an enabling of its seed production. It is evident that increases in plant density as a function of intensive defoliation are not restricted to the frequently documented effect on grass tillers but also can occur in many legume and forb species in species‐rich grasslands. 相似文献
9.
W. F. T. Hartill 《Potato Research》1989,32(3):283-292
Summary Below ground infection byRhizoctonia solani had little effect on the development of potato haulm. Severe infection caused an increase in the number of tubers initiated,
but a reduction in the total weight of tubers. Tubers often formed in leaf axils of severely infected plants. It is suggested
that these effects occur because assimilate production is not markedly affected by infection, but the compounds need to be
redistributed when lesion development on the stolons blocks transport to the usual sinks. 相似文献
10.
K. J. Oparka 《Potato Research》1987,30(3):477-483
Summary The effects of excising stolon apices, or entire stolons, on tuber yield and size distribution were examined forSolanum tuberosum L. cv. Record. Excision of the apex of all primary stolons did not significantly affect final tuber yield and number, new
tubers forming on branches of the primary stolon. Complete removal of the primary stolon, leaving only secondary stolons at
each node, produced large and significant losses in tuber yield and number. Removal of tuber initials from the primary stolons
significantly reduced yield but not tuber number. Although number was unaffected by removal of the primary stolon apex, tuber
size grade distributions were significantly altered in all stolon excision treatments. The results point to the importance
of primary stolons as tuber-bearing sites and emphasise the plasticity in tuber formation at a single node. 相似文献