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131.
玉米果穗剥皮辊型及其主要参数优选试验 总被引:1,自引:1,他引:1
在前人研究基础上,用实验法在室内专用试验台架上对玉米果穗剥皮辊型及其主要运动与结构参数进行多指标正交试验,以求进一步摸清各参数对剥皮性能影响程度及其变化规律,寻求较优参数组合,为研究设计米果穗剥皮机械提供科学依据。 相似文献
132.
Lemon (Citrus limon (L.) Burm. f.) is one of the most important Citrus fruit for Turkey because of its great amount of production and export. It has been cultivated for a long time in Turkey, and therefore variations for agronomical traits are likely among cultivated lemons due to bud mutations and, hybridizations. The objectives of this study were to determine variations for some selected agronomical traits and genetic markers among 12 new lemons derived from selections. Tree growth, yield, fruit quality, and molecular diversification of these clones were determined. After four years of evaluation, ‘Kutdiken’ M-51 indicated the highest canopy volume. For yield per tree, the best clone was ‘Kutdiken’ M-51. After five years of evaluation, ‘Kibris’ M-54 had the highest fruit weight and acidity. ‘Italian Memeli’ M-56 contained the lowest seed number and the highest total soluble solids. Molecular analysis, as assessed with 22 random amplification of polymorphic DNA (RAPD) and 11 inter simple sequence repeats (ISSR) primers, indicated that seven of twelve clones were separated with RAPD markers, whereas four were distinguished with ISSR markers. Combined analysis of RAPD and ISSR data detected that similarity values among the lemons clones were between 0.97 and 1.00. It can be concluded that variations in orchards are abundant and mainly due to mutations. 相似文献
133.
L.H. Wang X.H. Gu M.Y. Hua S.L. Mao Z.H. Zhang D.L. Peng X.F. Yun B.X. Zhang 《Scientia Horticulturae》2009
The root-knot nematodes (Meloidogyne spp.) are important nematode pests and cause serious diseases in pepper in the world. No molecular markers linked to the nematodes resistance N gene have been reported. In this paper, ‘Carolina Wonder’ (Capsicum annuum L.), a sweet pepper line resistant to root-knot nematode with N gene, ‘20080-5-29’ (C. annuum L.), an inbred line susceptible to root-knot nematode with good horticultural characteristics, and their F2 progeny with 320 individuals were used as materials. Evaluation of resistance and susceptibility of parental lines, F1 and F2 progeny inoculated with root-knot nematodes (Meloidogyne incognita) were carried out. ‘Bulked segregant analysis’ method was used to search for polymorphic markers from 512 pairs of AFLP primers. Based on the assessment of resistance and susceptibility and polymorphism of the AFLP marker in F2 population, the genetic linkage distance between the AFLP marker and the N gene was estimated. One AFLP marker E39/M41-339 was obtained and transferred to a SCAR marker amplifying a 315 bp DNA fragment linked to the N resistant allele and a 331 bp fragment linked to the N+ susceptible allele. The distance between the molecular marker and the nematodes resistance N gene is 6.3 cM. This research delivered a valuable tool for the marker assisted selection of nematodes resistance in pepper. 相似文献
134.
The conversion of forests and farmlands to human settlements has negative impacts on many native species, but also provides
resources that some species are able to exploit. American Crows (Corvus brachyrhynchos), one such exploiter, create concern due to their impact as nest predators, disease hosts, and cultural harbingers of evil.
We used various measures of crow abundance and resource use to determine crows’ response to features of anthropogenic landscapes
in the Puget Sound region of the United States. We examined land cover and land use composition at three spatial scales: study
sites (up to 208 ha), crow home ranges within sites (18.1 ha), and local land cover (400 m2). At the study site and within-site scales crow abundance was strongly correlated with land cover providing anthropogenic
resources. In particular, crows were associated with the amount of ‘maintained forest’ cover, and were more likely to use
grass and shrub cover than forest or bare soil cover. Although crows did not show a generalized response to an edge variable,
they exhibited greater use of patchy habitat created by human settlements than of native forests. Radio-tagged territorial
adults used resources within their home ranges relatively evenly, suggesting resource selection had occurred at a larger spatial
scale. The land conversion pattern of new suburban and exurban settlements creates the mix of impervious surfaces and maintained
vegetation that crows use, and in our study area crow populations are expected to continue to increase.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
135.
黄瓜根际促生菌的促生效应与防病作用 总被引:3,自引:0,他引:3
对黄瓜植物根际促生菌(PGPR)菌株的分离筛选、分类鉴定以及人们对其促生防病作用的应用和防病机制的研究现状进行了综述,以期为新型PGPR制剂的进一步研制、开发和应用提供参考. 相似文献
136.
Kullapapruk Piewthongngam Supachai Pathumnakul Kanchana Setthanan 《Agricultural Systems》2009,102(1-3):58-66
The poorly integrated cane supply planning between mills and cane growers in the Northeast of Thailand generates an excess of cane supplies that exceeds the mills’ capacity during the peak of harvest season. Each grower individually determines his/her cultivation plan by selecting planting dates and cultivars based on one’s own preference without taking into account the individual mill’s capacity and other growers’ plans. This situation causes most sugarcane grown in this area to reach its mature stage at the same period. In this study, we propose a framework of cultivation planning to cope with the problem. The focus of the cultivation plan is a long-term plan to determine the cultivation time, the cultivar selection and the corresponding prospective harvesting time window for each field such that overall sugar production is optimized.The crop growth model and a mathematical model are employed for yield simulation and optimization task. The crop growth model enables decision-makers to visualize cane production of each individual field at different dates with different cultivars and allow decision-makers to apply the mathematical programming to cultivation planning. The suggested framework has the potential to increase sugar production by 23% when compared to the traditional method. 相似文献
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140.
通过生理性解偶联调节氧化磷酸化效率可能是进化早期发展起来的一种普遍策略,对生命的存在至关重要. 解偶联蛋白(uncoupling protein,UCP)家族是位于线粒体内膜的转运蛋白,哺乳动物基因组中已发现5个成员,其中UCP1~UCP3紧密相关,而UCP4和UCP5(即BMCP1,brain mitochondrial carrier protein-1)与它们差异较大. UCP1~UCP4不仅在哺乳类、鸟类等恒温脊椎动物中普遍存在,而且在鱼类等变温动物中也被证实存在,但UCP5目前仅在哺乳类中被发现. 哺乳动物褐色脂肪组织的UCP1,介导呼吸链产生的质子梯度泄漏,使氧化产生的能量以热的形式散发,但鱼类等变温动物UCP1的功能尚待进一步研究确立. UCP2和UCP3在产热、控制活性氧生成、脂肪酸氧化以及肥胖、糖尿病的发生中均发挥重要作用,二者的转录调节较复杂. UCP4和UCP5与其他UCP关系较远,UCP4仅在脑中表达,而UCP5在脑中高表达,它们的功能还不十分明确,但研究表明很可能与UCP2和UCP3的功能相似. 相似文献