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1.
Java citronella ( Cymbopogon winterianus Jowitt., Family: Poaceae) is a perennial, multiharvest aromatic grass, the shoot biomass of which, on steam distillation, yields an essential oil extensively used in fragrance and flavour industries. It has a long initial lag phase. To utilize the crop resources more efficiently during this lag phase, a field experiment was conducted for two years (1995–97) in semiarid tropical climate to explore the feasibility of intercropping food legumes and vegetables in Java citronella. Among food legumes, greengram ( Vigna radiata (L.) Wilez.), and among vegetables, clusterbean ( Cyamopsis psoraloides D. C., syn. Cyamopsis tetragonoloba (L.) Taub.), tomato ( Lycopersicon esculentum Mill.) and lady's finger ( Abelmoschus esculentus Moench.) as intercrops did not decrease the biomass yield, essential oil yield of Java citronella and produced bonus yields of these crops over and above that of Java citronella. Maximum monetary returns were recorded by Java citronella intercropped with tomato or greengram. Java citronella intercropped with redgram ( Cajanus cajan (L.) Millsp.), horsegram ( Macrotyloma uniflorum (Lam.) Verd. syn. Dolichos biflorus Roxb.) and brinjal ( Solanum melongena L.) suffered significant biomass and essential oil yield reductions. Horsegram proved to be the most competitive intercrop producing least yields and minimum monetary returns.  相似文献   

2.
绿豆基因组SSR引物在豇豆属作物中的通用性   总被引:4,自引:0,他引:4  
分子标记的种间通用性可降低其开发成本,提高利用效率,也有助于促进遗传研究较薄弱物种的分子遗传学研究。本文选取绿豆、小豆、豇豆及饭豆材料各3份, 分析1 205对新开发的绿豆基因组SSR引物在这些材料中的扩增效果,结果显示绿豆基因组SSR引物在豇豆、小豆和饭豆中的通用性比率分别为50.0%、73.3%和81.6%;多态性比率分别为4.1%、1.7%和1.5%;在4个种间均通用的引物469对。这些通用性SSR引物将有助于这4种食用豆类在多样性评价、连锁图谱的构建、基因定位及比较基因组学等方面的研究。  相似文献   

3.
Productivity of maize ( Zea mays L.) legume intercrops is determined by soil, management, and environment. Planting sequence and time and N fertilization are easily controlled management factors but their effects on intercrop yields are not well understood. Maize grown in monoculture or intercropped with polebean ( Phaseolus vulgaris L.) or cowpea ( Vigna unguiculata [L.] Warp.) was studied for two growing seasons at Morgantown, WV. Crops were seeded in the following sequences: maize before legume, both at the same time, and legume before maize. Planting times were early May or mid June. Nitrogen was applied at 0 or 160 kg ha−1. Maize grain and forage, legume grain and forage, and total forage production were determined on a dry matter basis. Intercropping (average of all treatments) reduced maize grain and forage yields compared to maize in monoculture but had no effect on total forage production. However, total forage production was greatest when the seeding sequence was maize intercropped at the same time or before cowpea. Cowpea never produced grain, but forage production was almost double that of polebean. Maize produced most forage when seeded before the legumes, and the legumes produced most forage when seeded before maize. Early planting increased maize production and decreased legume production. Nitrogen increased maize grain, maize forage, and total forage yields but had not effect on legume forage production. It is concluded that maize/legume intercrops show promise for increasing forage production in temperate areas and more research on planting times and densities, weed control, harvesting and management is needed.  相似文献   

4.
Drought is an important yield-reducing factor for corn and soya bean which are the two major crops in the Delaware, Maryland and Virginia (Delmarva) region of the United States. Cowpea (Vigna unguiculata L. Walp.) is primarily grown in drier regions of the world where it is one of the most drought-resistant food legumes. Field experiments were conducted in which 10 genetically diverse cowpea genotypes were evaluated for adaptability to the Delmarva area. The cowpea genotypes were grown in rain-out shelters under non-water-stressed and water-stressed conditions. The results showed that under non-water-stressed conditions cowpea genotypes California Blackeye 5, Champion and Mississippi Silver gave higher seed yields, while genotypes White Acre, Six Week Browneye and Texas Cream 8 provided lower seed yields. Genotypes California Blackeye 5 and Champion gave comparatively better seed yields under water-stressed conditions. California Blackeye 5 was the highest seed-yielding genotype under both water-stressed and non-water-stressed conditions. The highest biological yield under non-water-stressed conditions was given by genotypes Two Crop Brown, White Acre and Elite, whereas under the water-stressed condition genotypes Texas Cream 8, California Blackeye 5, and Mississippi Silver gave higher biological yield. Genotypes Quickpick Pinkeye and Elite were identified as early maturing genotypes. The harvest index (HI) varied significantly among genotypes, with Texas Cream 8 having the lowest HI. Cowpea genotypes which gave higher seed yield under water-stressed conditions could play an important role in sustaining crop production in the Delmarva region.  相似文献   

5.
As water for irrigation purposes becomes increasingly scarce because of climate change and population growth, there is growing interest in regulated deficit irrigation (RDI) as a way to improve efficiency of water usage and farm productivity in arid and semi‐arid areas. Salinity is also becoming an important problem in these same regions. Experiments were performed to investigate the effects of RDI and salt stress on two legumes crops, common bean (Phaseolus vulgaris L.) and mungbean (Vigna radiata (L.) Wilczek); previous work showed contrasting responses to RDI by these two crops under field conditions. The seed and biomass yields of both crops were reduced as a result of increasing water deficit stress; however, mungbean was able to maintain the same proportion of its biomass in reproductive structures and maintain its harvest index under stress, whereas common bean’s decreased. In addition, photosynthesis in mungbean was higher than in common bean and higher at the same levels of transpiration. Finally, salinity stress did not affect the water potential, harvest index or the specific leaf weight of either crop. There were no interactions between salinity and crops or RDI levels, which suggest that the two crops do not differ in their response to salinity stress, and that RDI levels do not modify this response.  相似文献   

6.
Journal of Crop Science and Biotechnology - Chickpea (Cicer arietinum L.) is one of the most important food legumes in the world. However, Fusarium wilt is one of the major yield limiting factors...  相似文献   

7.
When one of the crops is a legume, intercropping has potential to reduce fertilizer nitrogen (N) needs and increase food quality. Total dry matter (DM) and grain yields of different plant populations of intercropped maize ( Zea mays L.) and climbing beans ( Phaseolus vulgaris L.), cowpeas ( Vigna unguiculata [L.] Walp.), or velvet beans ( Mucuna pruriens [L.] DC. var utilis [Wight] Bruck.) were compared in two experiments. Maize populations were 40,400 and 50,500 plants ha−1 in combination with climbing bean populations of 0, 20,200, 40,400 and 80,800 plants ha−1 in Experiment 1. In the second experiment, climbing beans, cowpeas and velvet beans at 215,200 plants ha−1 were intercropped with maize at 64,600 plants ha−1. Climbing beans contributed up to 5% to total DM yields in the first experiment. In the second experiment legume contributions to total DM were 20% for climbing beans, 12% for cowpeas and 8% for velvet beans. Increasing populations of maize and climbing beans increased grain and DM yields. Dry matter yield of maize was lowered by intercropping. However, DM yields of the intercrop were not different to maize sole cropped. Maize/cowpeas produced more total DM than maize/climbing beans. Cowpeas increased the total yield of crude protein by over 15% without lowering total DM yield of the intercrop compared to maize alone and are promising as a legume for intercropping with maize. Climbing beans show little promise as a possible legume for intercropping with maize.  相似文献   

8.
Journal of Crop Science and Biotechnology - Peanut (Arachis hypogaea L.) is one of the major oilseed legumes contributing to food security in Benin. Unfortunately, several constraints hamper its...  相似文献   

9.
优良牧草在肉兔生产中应用的研究   总被引:2,自引:0,他引:2  
(1郑州牧业工程高等专科学校,河南郑州 450011;2河南省新密市农业局,河南郑州 450011)  相似文献   

10.
15N-aided investigations were conducted to ascertain the Nj fixation and the nitrogen (N) contribution by mungbean ( Vigna radiata L.) and groundnut ( Aracbis hypogaea L.) when intercropped with maize ( Zea mays ). The study involved growing seven genotypes of the above legumes with maize in alternate rows in two separate experiments. A sole crop of maize was used as the reference crop to determine N2 fixation by the 15N methodology. Significant genotypic differences in pod yield and stover N content were observed in intercropped mungbean and groundnut. The percentage N derived from the atmosphere showed a genotypic variation of 31 to 45 % (7 to 10 kg N2 fixed ha−1O in mungbean and 47 to 69 % (9 to 18 kg N2 fixed ha−1) in groundnut. Harvest index for N varied from 58 to 77 % in mungbean and 55 to 75 % in groundnut. In groundnut, the uptake of soil N was significantly affected by the genotype. Assuming that the N contribution to the soil by the helow-ground plant parts was negligible, the removal of seeds at maturity resulted in a negative N balance in the soil in all the genotypes of mungbean. In groundnut, some genotypes produced a positive N balance in the soil. Owing to high N2 fixation capacity and low harvest index for N, groundnut showed a greater N supplementing ability than mungbean.  相似文献   

11.
The effect of different rates of potassium (K+) on shoot water potential, photosynthesis and carbon movement (using 14C) at the V3/4 growth stages was studied in mungbean ( Vigna radiata L. Wilczek), a drought-susceptible legume, and cowpea ( Vigna unguiculata L. Walp), a drought-tolerant legume, grown under low- and high-irrigation regimes under controlled conditions. Soil moisture and K+ affected all measured parameters in the two species. The rate of photosynthesis was higher at reduced water stress when K+ was applied. The impact was greater in cowpea, which had an inherently high rate of carbon assimilation. Mungbean and to a lesser extent cowpea allocated greater quantities of carbon to roots under dry conditions, especially with added K+. The distribution of 14C into other plant parts was also increased at higher rates of K+ application under both soil moisture regimes. Thus, application of K+ seems to have a beneficial effect in overcoming soil moisture stress and increasing physiological parameters and carbon partitioning in these two important tropical food legumes.  相似文献   

12.
The influence of different weed types (grass, broadleaved and sedge species) on growth and yield parameters of mungbean ( Vigna radiata L. Wilczek) was evaluated under field conditions. The presence of all types of weeks had the most significant effect on growth and yields of mungbean. Broadleaved species alone had a greater adverse effect than grasses, and the influence of sedges was the lowest. The adverse effect of weeds was most prominent on vegetative growth. The influence on yield components reduced with time. However, the adverse impact of weeds on yields was similar to that on vegetative growth. A significant correlation between weed biomass and yield loss was observed. The study indicated the critical competitive period to be in the vegetative phase. Some possible implications for selective weeding are presented.  相似文献   

13.
Bruchid beetles or seed weevils are the most devastating stored pests of grain legumes causing considerable loss to mungbean (Vigna radiata (L.) Wilczek). Breeding for bruchid resistance is a major goal in mungbean improvement. Few sources of resistance in cultivated genepool were identified and characterized, however, there has been no study on the genetic control of the resistance. In this study, we investigated the inheritance of seed resistance to Callosobruchus chinensis (L.) and C. maculatus (F.) in two landrace mungbean accessions, V2709BG and V2802BG. The F1, F2 and BC generations were developed from crosses between the resistant and susceptible accessions and evaluated for resistance to the insects. It was found that resistance to bruchids in seeds is controlled by maternal plant genotype. All F1 plants derived from both direct and reciprocal crosses exhibited resistance to the bruchids. Segregation pattern of reaction to the beetles in the F2 and backcross populations showed that the resistance is controlled by a major gene, with resistance is dominant at varying degrees of expressivity. Although the presence of modifiers was also observed. The gene is likely the same locus in both V2709BG and V2802BG. The resistant gene is considered very useful in breeding for seed resistance to bruchids in mungbean.  相似文献   

14.
N. Thurling  M. Ratinam 《Euphytica》1987,36(3):913-926
Summary The mean aim of this study was to identify an effective method of predicting cross-potential in respect of yield improvement of the cowpea (Vigna unguiculata (L.) Walp.) through hybridization and subsequent selection.Three prediction tests based on data collected from experiments with ten cowpea lines and the F1 and F2 generations of all possible crosses between these lines were evaluated. The three prediction tests were based on: i Yields of prospective parents. ii. General combining abilities estimated from F1 and parental data iii. Frequencies of superior plants in F2 populationsEach of the three procedures was used to identify the crosses with the lowest or highest yield potential, i.e. those crosses most likely to produce the greatest number of lines with yields higher or lower than those of either parent. Crosses selected on the basis of these criteria were evaluated in the following growing season on the basis of biometrical analysis of F2 and backcross populations and the performance of the respective F3 and F4 generations.Six different crosses were selected from the 45 tested on the basis of the three prediction tests. Analyses of F2 and backeross populations from each cross provided estimates of [d] the difference in parental means and 1/2D the additive genetic component which, in turn, were used to predict the frequency of transgressive inbred lines obtained by single-seed descent from the F2. Both crosses selected on the basis of F2 data were expected to produce a much higher frequency of transgressive lines than those selected on the basis of parental yields. The high potential cross selected on the basis of general combining ability was expected to produce a higher frequency of transgressive lines than the corresponding low yield potential cross. Replicated trails of F3 bulks of the selected crosses showed that high yield potential crosses were significantly higher yielding than low yield potential crosses for all prediction criteria. In a trial with 22F4 lines of each of the two crosses selected on the basis of parental yields and frequency of high yielding F2 plants, the high yield potential cross in each case had a greater mean and variance for seed yield than the corresponding low yield potential cross.It was concluded that parental yields provide a sound basis for an initial screening of prospective parents. This screening should identify a high yielding line which can be crossed with a number of contrasting lines to produce F2 populations for the final screening phase.  相似文献   

15.
A field experiment was conducted during July 1986–April 1988 at New Delhi, to evaluate the relative contribution of rainy-season legumes towards the growth and productivity of succeeding wheat ( Triticum aestivum [L.] emend. Fiori & Paol), find out economic optimum dose of nitrogen for succeeding wheat and screen a legume which can be best knitted in wheat based cropping system.
HD 2329 wheat performed better when grown after legumes than when grown after Local fodder sorghum ( Sorghum bicolor [L.] Moench). N economy in wheat was greater (65–78 kg/ha) after Sona clusterbean ( Cyamopsis tetragonoloba [L.] Taubert) and T-9 blackgram ( Phaseolus mungo L.) over sorghum. The economic optimum dose of N for wheat following pigeonpea ( Cajanus cajan [L.] Millsp.), soybean (Glycine max [L.] Merr.), groundnut ( Aracbis bypogaea L.), blackgram ( Phaseolus mungo L.) and clusterbean were 110.1, 103.6, 113.7, 109.6 and 92.3 kg/ha respectively.  相似文献   

16.
Journal of Crop Science and Biotechnology - Mungbean [Vigna radiata (L.) R. Wilczek var. radiata] is vital grain legume having nutritional and socio-economic importance, especially in the...  相似文献   

17.
Intercropping of corn with legumes is an alternative to corn monocropping and has a number of advantages, for example, lower levels of inputs, lower cost of production and better silage quality than monocrop systems. An experiment was carried out at two sites in 1993 and 1994 to investigate the effects of seeding soybean or lupin alone or in combination with one of three forages (annual ryegrass, Lolium multiflorum Lam.; perennial ryegrass, Lolium perenne L.; red clover, Trifolium pratense L.) on silage yield and quality. The intercrop plots received 90 kg ha−1 less nitrogen fertilizer than monocrop plots, which received 180 kg ha−1. Corn biomass yield had a variable response to the treatments, but showed no change at most site-years. Soybean and lupin biomass yields were decreased by intercropping (80–98 % for soybean, and 94–100 % for lupin). However, when corn growth was limited due to poor establishment at one site in 1994, soybean was able to grow well and produce yields similar to those of monocropped soybean. The three underseeded forages did not grow well during the period examined (up to silage harvest) and had no effect on the yield of any crop. Total silage yields were similar to corn monocrop biomass yields even during 1994 at the site with low corn population densities because soybean was able to compensate for reduced corn growth.  相似文献   

18.
Many alfalfa ( Medicago sativa L.) fields are sprayed each year with insecticides to control Egyptian alfalfa weevil ( Hypera brunneipennis ) and the alfalfa weevil ( Hypera postica ). Overseeding various species of legumes and grasses into established alfalfa has been proposed as a method to mitigate weevil damage without insecticides. Established fields of alfalfa were overseeded with legumes and grasses in randomized complete block designs in three years of study in a Mediterranean climate in the Sacramento Valley of California, USA. Several overseeding practices maintained or increased yields compared with the insecticide-sprayed treatment. Overseeding increased or maintained forage yield, eliminating the need for insecticides. However, overseeding did not prevent weevil damage to alfalfa. Overseeding is best used to extend the life of alfalfa stands in the final year of production, since overseeding can thin alfalfa stands. Market acceptance for mixed-species hay and harvest management of overseeded forages are the most important limitations to overseeding practices.  相似文献   

19.
Yield and Qualitative Characteristics of Indian Mustard ( Brassica juncea L. Czern.)
Indian mustard is required as raw material for the production of mustard. In field trials, farm trials and processing tests during several years evidence could be furnished, that the cultivation of the up to now foreign crop is possible on suitable sites in central Germany. On loess soils (soil value number more than 50) in regions with milder climatic conditions the grain yields attained in using of intensive specific cultivation methods on an average of about 30 dt/hectare. The results of the field trials confirmed by average yields of 14 16 dt/hectare in agricultural practice. The best farms attained grain yields up to 25 dt/hectare. With regard to raw material with a content of allyl mustard oil of more than 1.00 % also the demands of the food processing industry could be fulfilled by all lots produced on farms (the attained content of allyl mustard oil amounted to 1.00 1.40 %).
Climatic factors but also the observance of correct cultivation methods influence first of all the processing quality.  相似文献   

20.
Cowpea ( Vigna unguiculata L. Walp) is an important food legume grown under rainfed conditions in the tropics. However, the yield of this crop varies widely in most tropical ecosystems due to crop and environmental factors. Experiments were carried out to evaluate the effects of seed characteristics, soil moisture at planting and the season of crop establishment on growth and yield parameters of cowpea as these influence the productivity of the crop. Growth and yield of cowpea plants grown from small seeds with a high conductivity of their lea-chates were significantly lower than those grown from large seeds. Root growth of seedlings was most prominent under moderate soil moisture levels. Low soil moisture retarded root growth by reducing dry weights and suppressing the development of laterals. Shoot growth was more sensitive to increasing soil moisture stress than root growth. Planting cowpea in the wet season produced the highest yields. Within a season, growth and yield were higher when the crop was planted early. Establishment of the crop later in the season produced better quality seeds measured in terms of germination after controlled deterioration.  相似文献   

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