烟粉虱的发生及防治

总结了烟粉虱的形态特征、危害特性与发生规律,从多角度提出对烟粉虱的防治措施,以期为烟粉虱的防治提供参考。

A Preliminary Study on Breeding of Ideal Plant in Millet

To further increase millet yield, the ideal plant in millet has become the goal of high yield breeding for millet. Taking crossbreeding or dynamic breeding technique as dominant and technologies such as modern selection or system selection as subsidiary, progenies with ideal plant are selected by using new germplasms such as Lilvgu and Lizigu with the significant difference in plant type to other cultivars as parents. The ge- netic characteristics of new germplasms in breeding are also emphatically analyzed to summarize the breeding experience of ideal plant, which has been proved that the combination of ideal plant and heterosis utilization is one of the important ways to raise millet yield breakthrough.

Molecular characters and morphological genetics of CAL gene in Chinese cabbage

BcpCAL, the homologous gene of CAL, was isolated from Chinese cabbage. Unlike bobcat of cauliflower, BcpCAL did not hold the terminating mutation in the fifth e-con. After crosses of cauliflower with Chinese cabbage, the resultant hybrids failed to form curd, which implicates the genetic complement of BcpCAL to the mutated Bob- CAL in the function of curd formation. One of CAL gene isolated from the hybrid apparently comes from the female parent (Chinese cabbage) even though there are a few of the biases substituted and deleted. The result offers the molecular and genetic evidences for the Study of biological function of CAL in morphological genetics of curd.

FRACTAL PROPERTIES OF ROCK FRACTURE SURFACES

To give a better understanding of the morphological features of rock fracture surfaces within the framework of fractal geometry, the fractal characters of the rough surfaces in rock are analyzed according to the variogram method. The study elaborates the significance of the geometric parameters-fractal dimension D and the intercept A on a log-log plot to the surface structure. Investigation extends to the anisotropy and heterogeneity of rock fracture surfaces, and the scale effect on the fractal estimation. The present study indicates that fractal dimension alone may not be sufficient to characterize the surface roughness of rock Joints. A reliable estimation should take into account the combination of D and A.

Minor Morphological Features in Maria Archeological Ruins Using Thin Section Analysis

Maria sites are important historical sites, backing to the Byzantine period. The sites suffer from weathering noted as honeycomb, exfoliation and discoloration with white salt efflorescence at some parts. These are diagnostic features for salt weathering as confirmed by the laboratory investigations using thin section analysis. The salt is found to be from three sources, namely, water spray, chemical alteration of the mortar＇s carbonate content into sulfate salts by acid rain, and wet deposition of air pollutants on the surface of the stones ruins. The cracks noted in the structures of this archeological building are the results of landslides in this area. Knowledge of the archeological sites material examined can be greatly enhanced by understanding the process in their formation of degradation. This paper aims to describe the use of thin sections/micromorphology in the archeological sites. Analysis data of physical sitting, geology, geomorphology, and climate have been done to determine the main nature of hazards in this sites. Dynamic processing problems are existing along Alexandria coast including beach erosion, pollution and manmade. Thin section analysis is used to determine the factor in increasing the hazard level.

Leaf stable carbon isotope composition in Picea schrenkiana var. tianschanica in relation to leaf physiological and morphological characteristics along an altitudinal gradient

To understand the effects of leaf physiological and morphological characteristics on δ13C of alpine trees, we examined leaf δ13C value, LA, SD, LNC, LPC, LKC, Chla+b, LDMC, LMA and Narea in one-year-old needles of Picea schrenkiana var. tianschanica at ten points along an altitudinal gradient from 1420 m to 2300 m a.s.l. on the northern slopes of the Tianshan Mountains in northwest China. Our results indicated that all the leaf traits differed significantly among sampling sites along the altitudinal gradient(P<0.001). LA, SD, LPC, LKC increased linearly with increasing elevation, whereas leaf δ13C, LNC, Chla+b, LDMC, LMA and Narea varied non-linearly with changes in altitude. Stepwise multiple regression analyses showed that four controlled physiological and morphological characteristics influenced the variation of δ13C. Among these four controlled factors, LKC was the most profound physiological factor that affected δ13C values, LA was the secondary morphological factor, SD was the third morphological factor, LNC was the last physiological factor. This suggested that leaf δ13C was directly controlled by physiological and morphological adjustments with changing environmental conditions due to the elevation.

Latitudinal variation of leaf morphological traits from species to communities along a forest transect in eastern China

Comprehensive information on geographic patterns of leaf morphological traits in Chinese forests is still scarce.To explore the spatial patterns of leaf traits,we investigated leaf area(LA),leaf thickness(LT),specific leaf area(SLA),and leaf dry matter content(LDMC) across 847 species from nine typical forests along the North-South Transect of Eastern China(NSTEC) between July and August 2013,and also calculated the community weighted means(CWM) of leaf traits by determining the relative dominance of each species.Our results showed that,for all species,the means(± SE) of LA,LT,SLA,and LDMC were 2860.01 ± 135.37 mm2,0.17 ± 0.003 mm,20.15 ± 0.43 m2 kg–1,and 316.73 ± 3.81 mg g–1,respectively.Furthermore,latitudinal variation in leaf traits differed at the species and community levels.Generally,at the species level,SLA increased and LDMC decreased as latitude increased,whereas no clear latitudinal trends among LA or LT were found,which could be the result of shifts in plant functional types.When scaling up to the community level,more significant spatial patterns of leaf traits were observed(R2 = 0.46–0.71),driven by climate and soil N content.These results provided synthetic data compilation and analyses to better parameterize complex ecological models in the future,and emphasized the importance of scaling-up when studying the biogeographic patterns of plant traits.