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31.
32.
于2003年在湖南省汝城县益将国有林场天然残次阔叶林内设置试验样地和对照样地各3个,采用林地清理、补植、补播等手段促进天然更新,并分别于2006年和2011年进行2次人工促进干预;同时,在6个样地内各设置3个样方,共计18个样方,分别于2003、2008、2013年冬,对幼树、幼苗、萌条的数量及地径进行统计,并对样方内胸径≥5 cm的立木进行每木调查。结果表明:种子补播保存率43%,幼苗补植保存率20%,平均保存率32%。树高≤30 cm且地径0.5 cm、31 cm≤树高≤50 cm且0.5 cm地径0.7 cm幼树的数量下降率分别是对照样地的17.5%、21.59%,树高≥51 cm且地径0.7 cm幼树的数量下降率是对照样地的121.66%。2008年单位面积蓄积量是对照样地的2.28倍,2013年达到3.80倍;经过10年更新,单位面积蓄积量是试验前的11.57倍,对照样地单位面积蓄积量仅是试验前的2.55倍;单位面积蓄积量是对照样地的4.54倍。人工促进天然更新所需的人工成本为1 860元/hm2,仅为同期人工营造杉木幼林所需人工成本5 310元/hm2的35%。 相似文献
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Summary A landrace seed lot of runner bean (Phaseolus coccineus L.), obtained from the Budapest region, Hungary, was separated into five seed groups according to seed coat colour. 131 plants were grown randomly, and observed for 27 morphological and physiological characters. The collected data were analysed by ANOVA.Numerical taxonomy of the data employed Principal Components Analysis to generate scatter diagrams and Cluster Analysis to generate dendrograms, both before and after removing data on the four anthocyanin colour characters (seed coat, calyx, stem and flower colour) as these characters are probably controlled by a single major gene. The progenies from the five distinct parental seed groups showed much overlap in characteristics, indicating that they were not distinct lines but comprised a largely panmictic population.Some character associations were detected: plants from white seeds matured significantly later than those from black seeds, plants from white seeds with a few dark spots produced seeds significantly heavier than average, whereas those from white or black seeds produced significantly lighter seeds, although the average seed yield per plant did not differ significatly. 相似文献
36.
绿豆皮膳食纤维提取的研究 总被引:5,自引:0,他引:5
以绿豆皮为原料,采用加碱蒸煮法提取膳食纤维。通过单因素实验、正交实验和验证试验等,对绿豆皮膳食纤维提取率影响较大的浸泡温度、加水量、浸泡时间和碱浓度等因素进行了研究,并确定了最佳条件。实验结果表明,在浸泡温度50℃,液固比为5,浸泡时间9h,NaOH溶液质量分数为1.0%的条件下,绿豆皮膳食纤维的最佳提取率为64.2%。 相似文献
37.
Summary Genetics of resistance to Ascochyta fabae Speg. in Vicia faba L. was studied with a final objective to develop resistant faba bean varieties to Ascochyta blight. The study was conducted separately on 3 single spore isolates (AF10-2 and AF13-2 from Tunisia and AF4-3 from France) and belonging to different groups of virulence (GV1 and GV2). Important general combining ability (GCA) effects were found especially with isolates AF10-2 and AF4-3. Specific combining ability (SCA), although significant for the 3 isolates, was important only with AF13 -2, but less important than GCA. Additive gene effects were predominant to non-additive effects. Lines 29H and A8817 transmitted to their progenies resistance to the 3 isolates, whereas 14–12 and 19TB conferred resistance to their progenies only with isolates AF13-2 and AF4-3, respectively. In the material studied, resistance was generally controlled by dominant genes but also could be attributed to recessive genes although less frequent. Analysis of segregation in the F2 of 2 crosses between the resistant lines (A8817 and 29H) and the susceptible line (14–12) with isolate AF4-3 revealed dominant monogenic control at the level of leaves in the 2 resistant lines and, in addition, a recessive gene controlling resistance of stems. Non-allelic interactions were occasionally manifested and their origin appeared to be due to line 19TB. A recurrent selection scheme was proposed with the objective to develop improved open-pollination populations and synthetic varieties responding to the objective of the national Tunisian research programme on faba bean. 相似文献
38.
Summary The adaptability and productivity of cool-season food legumes (chickpea, faba bean, lentil, pea) are limited by major abiotic
stresses including drought, heat, frost, chilling, waterlogging, salinity and mineral toxicities. The severity of these stresses
is unpredictable in field experiments, so field trials are increasingly supplemented with controlled-environment testing and
physiological screening. For drought testing, irrigation is used in dry fields and rain-out shelters in damp ones. Carbon
isotope discrimination (Δ13C) is a well-established screen for drought tolerance in C3 cereal crops which is now being validated for use in grain legumes,
but it is relatively expensive per sample and more economical methods include stomatal conductance and canopy temperature.
Chickpea lines ICC4958 and FLIP87-59C and faba bean line ILB938 have demonstrated good drought tolerance parameters in different
experiments. For frost tolerance, an efficient controlled-environment procedure involves exposing hardened pot-grown plants
to sub-zero temperatures. Faba beans Cote d’Or and BPL4628 as well as lentil ILL5865 have demonstrated good freezing tolerance
in such tests. Chilling-tolerance tests are more commonly conducted in the field and lentil line ILL1878 as well as derivatives
of interspecific crosses between chickpea and its wild relatives have repeatedly shown good results. The timing of chilling
is particularly important as temperatures which are not lethal to the plant can greatly disrupt fertilization of flowers.
Salinity response can be determined using hydroponic methods with a sand or gravel substrate and rapid, efficient scoring
is based on leaf symptoms. Many lines of chickpea, faba bean and lentil have shown good salinity tolerance in a single article
but none has become a benchmark. Waterlogging tolerance can be evaluated using paired hydroponic systems, one oxygenated and
the other de-oxygenated. The development of lysigenous cavities or aerenchyma in roots, common in warm-season legumes, is
reported in pea and lentil but is not well established in chickpea or faba bean. Many stresses are associated with oxidative
damage leading to changes in chlorophyll fluorescence, membrane stability and peroxidase levels. An additional factor relevant
to the legumes is the response of the symbiotic nitrogen-fixing bacteria to the stress. 相似文献
39.
Growth trials were conducted outdoors in the UK to determine the yield, yield components and plant architectural differences
between determinate and indeterminate Phaseolus vulgaris bean plants. F3 lines derived from crosses between ‘Prelude’, a determinate cultivar and ‘V8’, an indeterminate landrace,
were grown together with the parents and ‘Carioca’, an indeterminate landrace from Brazil. Data were recorded on flowering
date, number of nodes on main stem at flowering, plant height at maturity, number of pods/plant, number of seeds/pod, number
of seeds/plant, 100-seed weight, seed mass/plant, percentages of diseased and healthy seeds/plant. Determinate F3 lines had
significantly lower (P < 0.05) seed mass/plant, fewer pods/plant, fewer seeds/pod, fewer seeds/plant, lower harvest index, shorter stems, earlier
date of flowering, fewer nodes at flowering and fewer healthy seeds/plant than indeterminate F3 lines. However, determinate
genotypes had significantly larger (P < 0.05) pods to accommodate their larger seeds compared with indeterminate lines. A similar situation was found when the
yield and yield components of ‘V8’, ‘Prelude’ and ‘Carioca’ were evaluated; the highest seed mass/plant was given by ‘V8’
and the lowest by ‘Prelude’. Furthermore, some indeterminate genotypes with Type IV growth habit yielded significantly higher
(P < 0.05) than the high-yielding parent, ‘V8’, indicating a positive influence on seed yield by crossing different genotypes. 相似文献
40.
Summary Five parents from each of four race groups of common bean (Phaseolus vulgaris L.) were hybridized to produce five crosses within each group. Also, five crosses were made for each of the six possible combinations among four groups. Parents, F1 and F2, and parents, F2 and F3 were evaluated for seed yield in 1990 and 1991, respecitively, at two locations in Colombia.Yield of parents belonging to Middle American races and crosses among them was higher than that of races of Andean origin. Positive correlations were found among the mid-parent value, F1, F2 and F3. Also, the mid-parent value predicted the mean seed yield of all possible lines that could be derived from the F-generation in 42 out of 47 crosses. Four crosses, all between common bean races of Andean and Middle American origin, indicated a possible loss of favorable epistatic parental alleles. On average, mean yield of interracial F1 hybrids was higher than that of intraracial ones.Positive heteroris (26.4%–123.8%) over the mid-parent in 31 crosses, and F1s yielding higher (23.7%–91.8%) than the high parent in 20 crosses and yielding higher (22.1%–53.2%) than the highest control among all parents (MAM 13) in 12 crosses, were found. Heritability, estimated by the parent-offspring regression, ranged from 0.42± 0.07 to 0.49±0.04. Expected and realized gains from selection (at 20% selection pressure) ranged from 10.3% to 21.0% over the mean of F1 hybrids and F2 and F3 population bulks. 相似文献