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991.
高含水率刀豆、茄子和青椒的等温解吸规律 总被引:1,自引:0,他引:1
对高含水率刀豆(普通浓度、高浓度预处理和未预处理)、茄子和青椒(普通浓度预处理)进行了静态下平衡含水率(EMC)的测定试验(在40℃、60℃和80℃的解吸环境温度,5%~88%的相对湿度下),得出了其反映平衡含水率与温湿度关系的等温解吸曲线,讨论了温湿度、预处理及种类对平衡含水率影响的规律。并对普通浓度预处理刀豆选择了最适宜的平衡含水率模型;EMC=[(1n(1-RH))/(-aT)]~(1/b),确定了其模型系数为:a=0.63,b=2.77。 相似文献
992.
993.
994.
Eleven accessions of an under-utilized legume, Mucuna pruriens (L.) DC. var. utilis (Wall. ex Wight) Baker ex Burck (velvet bean) were collected from four districts of South India and their agronomic characters
were evaluated. The vegetative growth characters such as the germination percentage, plant height, number of leaves and branches
per plant were recorded. The yield based characters such as the number of clusters/plant (4–14), number of flowers/cluster
(3–15) and the fertility index (66–91%) were observed. The seed yield reaches 2.9–6.9 t/ha. The number of seeds per pod, seed
weight and the seed recovery percentage were also calculated. The level of diversity in the agrobotanical traits of velvet
bean observed in the present study could be of interest in a breeding programme. 相似文献
995.
Seed compositional and disease resistance differences among gene pools in cultivated common bean 总被引:5,自引:0,他引:5
F.M.A. Islam K.E. Basford C. Jara R.J. Redden S. Beebe 《Genetic Resources and Crop Evolution》2002,49(3):285-293
It is widely accepted that two major gene pools exist in cultivatedcommon bean, one Middle American and one Andean. Recently another gene pool,designated as North Andean and a fourth group (not considered to be adistinct gene pool) have been reported by the senior author and hiscolleagues. Many of the agronomic and seed compositional attributes of the twomajor gene pools are well known, but the seed compositional value and diseaseresistance of the North Andean gene pool has not yet been characterized. Torectify this situation, the seed compositional characters, percentage of proteinconcentrations (phaseolin, lectin and -amylaseinhibitor), the nutrient elements (calcium, phosphorus, iron andzinc) and the disease and pest attributes (angular leaf spot,anthracnose, common bacterial blight and empoasca damage) were considered.The Middle American gene pool gave higher lectin, calcium, phosphorus, sulfurand zinc than the Andean gene pool but lower phaseolin and iron. The NorthAndean gene pool is more like the Andean gene pool for phaseolin, resistance toangular leaf spot and anthracnose from Andean pathogen isolates, but more likethe Middle American gene pool for lectin, zinc, sulfur and resistance toanthracnose from Middle American pathogen isolates. On the other hand, it hadthe highest iron concentration and was more resistant to common bacterialblight. These results indicate the potential value of this gene pool in a commonbean breeding program. 相似文献
996.
Mariangela?HungriaEmail author Rubens?José?Campo Iêda?Carvalho?Mendes 《Biology and Fertility of Soils》2003,39(2):88-93
Cropping in low fertility soils, especially those poor in N, contributes greatly to the low common bean (Phaseolus vulgaris L.) yield, and therefore the benefits of biological nitrogen fixation must be intensively explored to increase yields at a low cost. Six field experiments were performed in oxisols of Paraná State, southern Brazil, with a high population of indigenous common bean rhizobia, estimated at a minimum of 103 cells g–1 soil. Despite the high population, inoculation allowed an increase in rhizobial population and in nodule occupancy, and further increases were obtained with reinoculation in the following seasons. Thus, considering the treatments inoculated with the most effective strains (H 12, H 20, PRF 81 and CIAT 899), nodule occupancy increased from an average of 28% in the first experiment to 56% after four inoculation procedures. The establishment of the selected strains increased nodulation, N2 fixation rates (evaluated by total N and N-ureide) and on average for the six experiments the strains H 12 and H 20 showed increases of 437 and 465 kg ha–1, respectively,in relation to the indigenous rhizobial population. A synergistic effect between low levels of N fertilizer and inoculation with superior strains was also observed, resulting in yield increases in two other experiments. The soil rhizobial population decreased 1 year after the last cropping, but remained high in the plots that had been inoculated. DGGE analysis of soil extracts showed that the massive inoculation apparently did not affect the composition of the bacterial community. 相似文献
997.
998.
不同抗旱性绿豆突变体的抗旱生理特性 总被引:2,自引:1,他引:2
对抗旱性不同的4个绿豆材料〔包括3个突变体172-3(高抗)、159-1(中抗)、145-1(弱抗)和原材料中绿2号(不抗)〕在不同生育期不同程度水分胁迫下的抗旱生理特性进行了研究。发现随着水分胁迫的加剧,抗旱性强的突变体其脯氨酸(proline,Pro)积累量加大,膜透性损伤程度变小,MDA含量增加幅度小,SOD活性明显高于抗性低的品种,表明这些生理特性与绿豆的抗旱性有关。 相似文献
999.
Giuseppina Logozzo Rosa Donnoli Leonardo Macaluso Roberto Papa Helmut Knüpffer Pierluigi Spagnoletti Zeuli 《Genetic Resources and Crop Evolution》2007,54(8):1763-1779
Common bean (Phaseolus vulgaris L.) was introduced in Europe from both Mesoamerican and Andean centres of origin. In this study, a collection including 544
accessions from all European regions showed that the Andean phaseolin types ‘T’ (45.6%) and ‘C’ (30.7%) prevailed over the
Mesoamerican ones ‘S’ (23.7%), and accessions with cuboid seed shape (34.9%), maroon coat darker colour seed (44.3%), uniform
seed colour (69.6%) were the most frequent. European accessions with phaseolin ‘S’ showed a significantly larger average seed
size compared to those from America in the same phaseolin class while those presenting ‘T’ and ‘C’ phaseolin did not. This
suggests that, during crop expansion in Europe, sampling or selection favoured the large-seeded races within the Mesoamerican
‘S’ gene pool or, possibly, introgression from Andean germplasm did occur. A core collection was developed using sampling
approaches based on the information available in the genebank databases and on phaseolin patterns. Four sampling strategies
were used: simple random sampling, and three random-stratified samplings, by logarithm of frequency of accessions by country,
by European region, and by phaseolin pattern, respectively. Two sampling strategies resulted in core collections significantly
different for phaseolin electrophoretic patterns from the whole collection. Stratification by phaseolin patterns increased
the frequency of ‘S’ types (‘C’ type = 33%, ‘T’ type = 5.7% and ‘S’ type = 31.3%). The core collections were validated using
seven seed characters, and no significant difference was observed in all strategies. This first developed European bean core
collection will help to assess the contribution of the two American gene pools to the European germplasm and their relative
importance for breeding purposes. 相似文献
1000.
Hani Saudy Nemat Noureldin Manal Mubarak Waleed Fares Mona Elsayed 《Archives of Agronomy and Soil Science》2020,66(3):414-425
ABSTRACTA sustainable agricultural tactics for countering a possible phosphate shrinking should comprise the releasing of legacy soil phosphorus (P), in parallel to lowering P fertilizer load, and increasing the use of recycled P sources with economic crop yield in mind. Therefore, a field trail was conducted to estimate the possibility of choosing the appropriate cultivar as a tool to raise the use efficiency of reserved soil P. Herein, three faba bean cultivars (Sakha-3, Nubaria-1 and Giza-843) were evaluated under five applications of P fertilizer (rock phosphate, super phosphate, Bacillus megaterium, rock phosphate+B. megaterium, and super phosphate+B. megaterium). Findings showed that the lowest value of estimated available P in soil after harvest was obtained from plots sown by Sakha-3 plants and fertilized with super phosphate+B. megaterium. Plots sown with Nubaria-1 and fertilized by rock phosphate+B. megaterium or B. megaterium (for weight of 100 seeds and seed yield) in addition to super phosphate+B. megaterium (for seed yield) produced the maximum increases. The highest P recovery efficiency was achieved with Nubaria-1 inoculated by B. megaterium alone. In conclusion, super phosphate+B. megaterium × Nubaria-1 achieve maximum crop returns and secure high short-term recovery of applied P. 相似文献