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1.
2.
Peas (Pisum sativum L.) are exposed to waterlogging at germination when grown as relay in rice‐based cropping. Ninety‐one germplasm accessions were evaluated in relay (sown in waterlogged soil), and subsequently 10 diverse genotypes compared under relay and sole cropping (conventional tillage sowing) over two seasons in Bangladesh. Contrasting genotypes, BM‐3, NL‐2 and Kaspa, were further evaluated in three waterlogging treatments (drained control, 4 and 8 days waterlogging) in the glasshouse. Conspicuous variation in waterlogging tolerance at germination was observed in the field and confirmed under controlled conditions. In relay sowing in 2011, emergence of a few genotypes was affected by waterlogging. In 2012, emergence in relay was severely affected (12 plants/m2) compared to sole sowing (37 plants/m2). Among genotypes BM‐3 had 6 plants/m2 emerge, which all subsequently died, in contrast to NL‐2 in which emergence was 13 plants/m2 with all plants surviving. In the glasshouse, there was 14% emergence in BM‐3, 40% in NL‐2 and 55% in Kaspa after 8 days of waterlogging. Such marked differences in waterlogging tolerance at germination in the model pea are the first reported and illustrate prospects for selection to improve adaptation to relay sowing in South Asia.  相似文献   
3.
豌豆根腐病研究进展   总被引:2,自引:0,他引:2  
根腐病是豌豆根部的重要病害之一,在世界各地豌豆产区均有发生,是制约豌豆产业持续健康发展的因素之一。世界上尚未发现对根腐病完全免疫的豌豆品种,防治方法主要以农业防治和化学防治为主。本文从豌豆根腐病的发生与分布、病原菌的分类及特点、抗性鉴定及评价标准、种质资源、分子标记及防治策略等方面对国内外豌豆根腐病研究现状进行综述。并提出抗病育种和未来豌豆根腐病综合防治的研究方向。  相似文献   
4.
磺酰脲类除草剂药害规律的研究   总被引:9,自引:0,他引:9  
采用作物主根长法测定了常用两种磺酰脲类除草剂对玉米(Zea mays L.)农大1236和豌豆(Pisum sativum L.)中碗6号的相对毒力,玉米试验结果表明,以IC50值比较,氯磺隆、胺苯磺隆对玉米的毒力较高,容易造成药害。豌豆试验结果表明,豌豆对氯磺隆和胺苯磺隆比玉米更敏感。离体玉米和豌豆ALS酶的研究表明,豌豆的ALS对两种磺酰脲类除草剂较玉米更敏感,氯磺隆对两种作物的ALS抑制作用也较胺苯磺隆强。  相似文献   
5.
M. Bencheikh  A. Gallais 《Euphytica》1996,90(3):257-264
Summary Six lines of Pisum were tested in vitro for their ability to produce somatic embryos from apices. Significant quantitative variation was observed. Inheritance of the ability to form somatic embryos was studied using a diallel cross among six different lines. About 80% of the observed genotypic variation was due to additive effects. There is a tendency for the favourable genes to be recessive. It appears that there are two genetic systems involved. Analysis of the distribution of F3 families means from a cross among two extreme lines seems to indicate the presence of a few major genes in the control of somatic embryogenesis of pea.  相似文献   
6.
D. Roy Davies 《Euphytica》1976,25(1):717-724
Summary A cellulose acetate electrophoretic technique has been used to characterise the storage proteins present in pea seeds in order to try and determine the proportions of proteins present which are enriched in sulphur amino-acids. Some of the eight varieties examined were shown to differ in their proportions of the various storage proteins. When the proteins were separated and estimated quantitatively and also characterised by their sub-unit composition, it was shown that cellulose acetate electrophoresis of crude protein extracts or of whole globulins did not give the degree of resolution required. The procedures which have to be undertaken in order to obtain this information are considered, and the difficulties of incorporating them into a plant breeding programme discussed.  相似文献   
7.
N. U. Haase 《Plant Breeding》1993,111(4):325-329
Rapid estimation of the amylose content of pea starch is of particular importance in breeding for pea starches high in amylose. An amylose test for starch in fresh potato tubers was adapted for use with high-amylose pea flour. Wavelengths for photometric detection were slightly changed, and the iodine concentration could be reduced. Defatting of the flour was not necessary. Reproducibility of the analyses was good (s% <3; n = 95). Variability of amylose content was investigated for different potato, barley and pea varieties. An analysis of the F4-generation of a crossing experiment with peas underlined the specific suitability of this rapid test method for supporting breeders' activities.  相似文献   
8.
The present study investigated impact of exogenous application of indole acetic acid (IAA; 10 and 100 μM) in pea seedlings under hexavalent chromium (Cr VI; 50, 100 and 250 μM). Cr and 100 μM IAA alone as well as in combination decreased seed germination rate compared to control. However, under Cr phytotoxicity, addition of 10 μM IAA recovered seed germination rate to the level of control. Exposure of pea seedlings to Cr and 100 μM IAA during their early stage caused decrease in fresh mass, length, protein and nitrogen contents of roots and shoots compared to control. Treatment of pea seedlings with Cr resulted in a rapid accumulation of this metal in roots and shoots. Moreover, addition of 100 μM IAA together with Cr, further increased accumulation of this metal in roots and shoots compared to Cr treatments alone. Treatment of pea seedlings with Cr and 100 μM IAA, resulted in a marked decrease in nitrate reductase, nitrite reductase, glutamine synthetase and glutamate synthase (GOGAT) activities (except 50 μM Cr alone for GOGAT), and an increase in ammonium content and glutamate dehydrogenase activity. Parameters related with oxidative stress, i.e. superoxide radicals and reactive carbonyl groups (protein oxidation) were increased by Cr and 100 μM IAA compared to control. By contrast, addition of 10 μM IAA together with Cr, alleviated negative effect of Cr on growth, protein, nitrogen and nitrogen metabolism, and led to decrease in oxidative injuries caused by Cr. The data indicate that 10 μM IAA protects pea seedlings during the early growth period against Cr phytotoxicity by regulating Cr accumulation and oxidative damage. However, addition of 100 μM IAA together with Cr showed opposite responses.  相似文献   
9.
四种药用植物的核型分析   总被引:2,自引:0,他引:2       下载免费PDF全文
四种药用植物的核型分析黄少甫赵治芬关键词豪猪刺接骨木芫荽箭舌豌豆染色体数目核型豪猪刺(BerberisjulianaeSchneid.)为小檗科(Berberidaceae)小檗属(Berberis)植物,灌木。分布于贵州、湖北、四川等省海拔1000...  相似文献   
10.
Annual (Pisum sativum L. and Vicia sativa L.) and perennial (Trifolium repens L. and Lotus corniculatus L.) leguminous species were grown in pots containing samples from the ash layers of two Cambisols under Pinus sylvestris L., which has been affected by high-intensity wildfires 3 and 15 days before the sampling. The gramineous Lolium perenne L. was cultivated as a second plant after Trifolium and Lotus harvesting. Three treatments were compared: soils without fertilization and soils fertilized with two doses of poultry manure (1 and 2 g total N kg-1 dry soil). The aim of the work was to study the capacity of the ash layer to sustain vegetation and the influence of plants and organic manure on the recovery of vegetation cover, ash layer fixation and soil structure formation to avoid erosion. The ash samples were able to sustain vegetation without fertilization. The organic manure increased the yields of all the plants tested, the lower dose being the optimal for the first crop whereas the higher dose was beneficial for the second crop. The annual legumes grew very quickly. The mixture of Trifolium and Lotus seemed very suitable for reclamation of soil degraded by wildfires because Trifolium produced more phytomass than Lotus in the first growing stages whereas the development of Lotus was higher in the later growing stages. Ash layer conditions did not inhibit nodulation, which was, however, stimulated by the organic manure, particularly in the case of Lotus. Lolium after perennial legumes was the best plant combination because it produced the highest phytomass, particularly root phytomass, and thus improved vegetation cover and ash layer fixation. All the plants tested improved the formation of soil aggregates, particularly the combination of perennial legumes and Lolium. However, wet aggregate stability was higher when plants were grown on soils fertilized with poultry manure than when plants were cropped on unmanured soils, which points to the favourable influence of the organic manure on soil aggregation.  相似文献   
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