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61.
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We recently developed a method to identify methionine-containing proteins and quantitate their methionine contents [4]. We applied this method to soybeans and identified relatively methionine-rich proteins (MRP) among the albumins. By acidic methanol extraction of the albumins, we obtained a group of low molecular weight methionine-cysteine rich proteins (MCRP) that analyzed 4.0% methionine and 8.8% cysteine. MCRP made up 1–2% of the total protein in soybeans. Reversed-phase HPLC purification of MCRP yielded a protein peak that exhibited a single major band on denaturing polyacrylamide gel electrophoresis, had a molecular weight of 16kD and contained 6.2% methionine and 18.8% cysteine. We are cloning the gene for this protein. Increasing its level through genetic engineering could increase the methionine-cysteine content of soybeans.  相似文献   
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Deviation from optimum percentage (DOP) and Diagnosis and Recommendation Integrated System (DRIS) are methodologies for leaf analysis interpretation. DOP calculates the deviation as a percentage for each essential element while DRIS calculates the average deviation for different ratios that include each element. A vine survey was undertaken for 11 years in La Rioja, northeastern Spain, to establish nutritional references for cv. ‘Tempranillo’ (Vitis vinifera L.). Diagnosis of nitrogen, phosphorus, potassium, calcium, and magnesium were performed by DRIS and DOP on the dataset for leaf blade and petiole, at both flowering (n = 684) and veraison (n = 801) with a moderate-yield criterion (3,800–10,000 kg·ha?1). Important differences between DOP and DRIS were found when a diagnosis using the same dataset was performed. In spite of the differences, the regression equations obtained are an acceptable adjustment between both methods for phosphorus (P) and magnesium (Mg) in blades and petioles, and for potassium (K) in blades.  相似文献   
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Grey mould is reported in the vineyards of Castilla y León, Spain, every year. However, the natural populations of the pathogen have yet to be properly characterized. Vineyards from six wine-producing areas were surveyed in 2002 and 2007, sampling from bunches of grapes with and without symptoms. A total of 283 Botrytis field isolates were selected for physiological and genetic analyses. Botrytis cinerea isolates predominated in the population, although isolates belonging to Botrytis pseudocinerea and Botrytis prunorum were also identified. These two species are recorded for the first time in Spain in this work. In addition, two isolates closely related to Botrytis californica were identified. Physiologically, the B. cinerea population is very diverse, displaying a normal distribution of aggressiveness values in Vitis vinifera leaves, suggesting a quantitative nature for this trait. Several isolates unable to cause infection were identified, most of them belonging to a mycelial morphotype. Population genetic analysis revealed that genotypic diversity is high and that multiple infections of the same bunch of grapes by different genotypes occur frequently. The high genotypic diversity observed, an even distribution of both mating types and the linkage disequilibrium values detected support a mixed mode of reproduction with low levels of clonality. The wine-producing area in which each isolate was collected imposed a low degree of population differentiation, an effect that does not depend solely on the geographic distances but rather on the management practices used by growers and wine producer associations.  相似文献   
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Context

Cultivated lands have undergone a shift towards intensification and increased productivity, favoring provisioning services at the expense of regulating and cultural services. Cultivated lands have rarely been researched as a provider of cultural services.

Objectives

The overarching goal of this study is to assess sense of place across cultivated lands. To do so, we used participatory mapping to elicit public knowledge of the past and present coverage of agricultural areas, as well as to reveal the public sense of place attached to cultivated lands and perceptions about future land-use pathways.

Methods

This study was conducted in an agrarian and rural region of SE Madrid (Spain), where we did ecosystem service participatory mapping workshops with key stakeholders related to the agrarian sector: farming professionals, land-use decision-makers and planners and other local actors.

Results

We identified linkages between cultivated lands and sense of place as a key cultural service. The locations most pinpointed for its sense of place overlapped with cultivated lands. The future land-use pathways that showed the highest agreement between the likelihood and interest in their promotion were the increases in green and/or protected areas and orchards. Extensive crops and urban areas the land-use pathways with the highest dissonance.

Conclusions

The results encourage land planners and researchers to approach landscape values in relation to the sense of place. We concluded that cultivated lands present a sense of place, and this link has the possible to root society in agricultural landscape through the establishment of belongingness, stewardship and care connections.

  相似文献   
68.
Tube shelters were designed to protect against browsing, but they improve seedling survival in Mediterranean dry climates. Mechanisms for this response, however, are not fully understood and this knowledge can be useful to help design optimal tube shelters for Mediterranean species and climates. Our objective in this study was to determine if the positive effect of tube shelters is due to enhanced growth during the wet season or to reduced light stress during the dry season. We performed two independent experiments. In the first, we assessed root growth during the wet season in two Mediterranean species with contrasting light tolerance (Quercus ilex L. and Pinus halepensis Mill.) growing in tubes with varying light transmissivity. In the second experiment, we studied the response of a Quercus ilex plantation to different shelter treatments. Root growth during the wet season was reduced with decreasing light transmissivity in the shade intolerant P. halepensis, but not in the shade tolerant Quercus ilex. Survival of Q. ilex shaded by a mesh shelter only during summer was higher than in unsheltered seedlings and similar to the survival in tube and mesh shelters during the whole season. This suggests that shade during the dry period was the main factor explaining survival in this species. This effect could be related to the lower leaf temperature recorded in sheltered seedlings. We conclude that Q. ilex (and perhaps other late successional, shade tolerant Mediterranean species) should be planted in tubes with the currently used light transmissivity because these shelters reduce light stress in summer without impairing root growth in the wet season. However, current tubes impair root growth in P. halepensis (and likely other pioneer, shade intolerant Mediterranean species), so higher transmissivity tubes may be necessary. Optimal transmissivity for tube shelter in Mediterranean climates is species-specific and identifiable as the point that minimizes light stress during summer without impairing root growth in the wet season.  相似文献   
69.
The inhabitants of Northeast of Mexico use an infusion of leaves from Artemisia ludoviciana as an antidiarrheal remedy. The aqueous, methanol, acetone and hexane leaf extracts from mature plants were found to be active in vitro against the parasitic protozoa Entamoeba histolytica and Giardia lamblia.  相似文献   
70.
Summary Inheritance of the duration from seeding to heading in rice was analyzed by dividing the vegetative growth period into the basic vegetative phase (b.v.p.) and the photoperiod-sensitive phase (p.s.p.). Concurrent determination of the two physiologic phases on pure lines and hybrids was facilitated by testing vegetative tillers of the same plant under two photoperiods.In nine crosses of photoperiod-sensitive by insensitive arieties where the parents differed appreciably in b.v.p. estimates obtained under a 10-hour photoperiod, two to three Ef genes of relatively discrete effect controlled the F2 variation in b.v.p. Short b.v.p. was controlled by dominant genes of cumulative but unequal effect. In three other sensitive × insensitive crosses where the parents differed less in b.v.p., the F2 segregation could be ascribed to two to four pairs of metrical alleles with equal or unequal effect.Concurrent data obtained from sensitive × insensitive crosses grown under a 16-hour photoperiod indicate the action of one or two (duplicate) dominant Se genes in controlling strong sensitivity to a long photoperiod. One insensitive variety appeared to carry a recessive inhibitor, i-Se. The Se gene(s) is epistatic to the Ef genes in the expression of earliness under a short photoperiod. Pooled data also suggest an association between photoperiod sensitivity and a short b.v.p. in a large proportion of F2 plants.Field data on the two principal components of the vegetative growth period obtained under natural daylength generally indicated agreement with duplicate plantings grown under controlled photoperiods. Segregation for the optimum photoperiod and critical photoperiod under a changing photoperiod in the field plantings probably resulted in modified expression of the Se and Ef genes.Research supported in part by grant GB-2417 from the U.S. National Science Foundation.  相似文献   
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