Monoterpenoid and morphological differentiation within Pinus cembroides

Wood of Pinus cembroides from 232 trees sampled in 23 localities throughout its range in the United States and Mexico has been analysed for monoterpenes. With a few exceptions the trees of the continental populations from the state of Hidalgo northward produced α-pinene as the main monoterpene. The majority of trees of the southern populations (subsp. orizabensis) from the state of Puebla and adjoining regions of the neighboring Veracruz and Tlaxcala produced 3-carene in appreciable amounts. The population from Baja California (subsp. lagunae) produced monoterpenes of the sabinene family (thujene, sabinene, γ-terpinene, terpinolene and $\text{p-}\text{cymene}$) as the main constituents. The variations in morphological characters, including number of needles per fascicle, number of stomatal rows in needles, number of resin canals in needles, as well as other characters of the internal needle morphology, needle length and thickness, needle retention, thickness of seed shells, bark and cone characteristics, rate of growth and cotyledon number either paralleled or did not contradict the chemical variations. The evolution of the southern populations (subsp. orizabensis) into a separate group most likely resulted from geographic separation and climatic differences, while the evolutionary separation of the Baja California trees (subsp. lagunae) was connected with northwestern movement of the California coastal region from Miocene onward and the formation of Sierra Madre Occidental resulting in separation of this population from the mainland populations by the gap of the Gulf of California and the coastal mountain ranges.     

Monoterpene differentiation in relation to the morphology of Pinus culminicola,Pinus nelsonii,Pinus pinceana and Pinus maximartinezii

Wood from 92 trees of Pinus culminicola, Pinus nelsonii, Pinus pinceana and Pinus maximartinezii from nine localities and oleoresin from several trees of Pinus nelsonii from one Iocality were analyzed for monoterpenes by gas liquid chromatography. Monoterpenes of Pinus nelsonii were composed mainly of α- and β-pinenes, while the main constituent of the monoterpenes of Pinus pinceana and Pinus maximartinezii was limonene, present in amounts of about 90 percent. The similarity in composition of the monoterpenes of Pinus pinceana and Pinus maximartinezii strongly supports the contention of Rzedowski [12] of the close evolutionary relation of the two pines. Pinus culminicola wood produced monoterpenes composed mainly of α-pinene, sabinene, terpinolene and limonene, with other monoterpenes occurring sporadically in sizeabie amounts. The variability between individual populations was relatively high, probably due to their long-time isolation by the intervening low-elevation barriers. Appreciable differences were found in compositions of monoterpenes from stem and from twigs of Pinus culrninicola.     

Pollen morphology of the Thymelaeaceae in relation to its taxonomy

 Pollen morphology of the four subfamilies of Thymelaeaceae sensu Domke (1934) was examined using LM, SEM and TEM. The variation of the exine architecture allows to distinguish four pollen types and three subtypes. Distribution of pollen types proves to be widely correlated with the occurrence of characters from wood anatomy and flower morphology. If pollen types are connected with subfamilies sensu Domke (1934), Gonystyloideae, Thymelaeoideae and Synandrodaphnoideae are stenopalynous, whereas Aquilarioideae are eurypalynous. Based on pollen morphology as well as on other characters it is evident that Aquilarioideae are not monophyletic. Its genera Aquilaria and Gyrinops are more closely related to Thymelaeoideae and Synandrodaphnoideae than to other genera of Aquilarioideae sensu Domke (1934). The remaining genera of Aquilarioideae Deltaria, Solmsia and Lethedon are most similar to Gonystyloideae and therefore are included in this subfamily, as it was suggested by Airy Shaw (1979). Furthermore, palynological and other characters favour the transfer of Octolepis from Aquilarioideae to Gonystyloideae. The re-circumscribed Aquilarioideae together with Thymelaeoideae and Synandrodaphnoideae are shown to form a monophyletic group. Received August 8, 2001 Accepted December 7, 2001     

Cytokinins and bud morphology in Pinus radiata

Cytokinins (CKs) play essential roles in the regulation of plant growth and development. In the previous paper (Zhang et al. 2001), we reported the detection and identification of a wide spectrum of CKs, including several novel forms, in the buds of Pinus radiata D. Don. In this paper we examine the relationship between the CKs and buds from juvenile and adult trees of P. radiata. During development the morphology of buds alters significantly, from buds bearing primary needles during their juvenile phase to buds sealed in scales at the adult phase. The morphology of adult buds is a very stable character, as fascicle meristems released from apical dominance, or cultured in vitro, produced only secondary needles. However, exogenous CK causes the adult buds to revert to juvenile bud development in vitro . Analyses of the endogenous CKs revealed that juvenile buds had a relatively higher level of isopentenyladenine and isopentenyladenosine, extremely low levels of phosphorylated CKs and a relatively low level of novel CK glycosides. The adult buds contained lower levels of free base and riboside CKs but very high levels of phosphorylated CKs and novel CK glycosides. Possible roles for CKs in the regulation of bud development are discussed.     

Oviposition preference of cotton leafhopper in relation to leaf-vein morphology

Abstract:  The oviposition preference of the cotton leafhopper, Amrasca biguttula biguttula (Ishida) was investigated in relation to leaf-vein characteristics of 12 plant species, namely okra, cotton, castor, pigeonpea, cowpea, cluster bean, green gram, egg plant, sesame, country mallow, portia tree and shoe flower. Observations on the oviposition of the leafhopper under no-choice conditions were recorded on three occasions during the peak period of leafhopper incidence in the field. On all three occasions the leafhopper rejected green gram, shoe flower and portia tree for egg-laying, thereby indicating non-acceptance of these plants for oviposition. For the remaining plants, the number of eggs per leaf differed significantly. Okra received the maximum number of eggs. The lateral veins of castor, cotton, cowpea, egg plant and country mallow leaves received more eggs in comparison with the main vein and subveins whereas in okra the subveins received the highest number of eggs followed by lateral and main veins. The leaves of cluster bean, pigeonpea and sesame were devoid of subveins. In cluster bean and sesame the lateral veins received more eggs than the main vein but in pigeonpea the main vein received more eggs than the lateral veins. Correlations of trichome density and length with the number of eggs laid in different veins were non-significant. All types of veins in okra leaves were thicker than the rest of the test plants, which might have stimulated more egg laying in okra. The thickness of each category of vein, namely main vein ( r =0.60), lateral veins ( r =0.65) and subveins ( r =0.56) was found to be positively correlated with the number of eggs laid. The length of the main and lateral veins were also found to be positively and significantly related to the number of eggs laid. It can be concluded from the present investigations that leaf-vein thickness and length are crucial factors in influencing the oviposition behaviour of the cotton leafhopper.     

南五味子属花的形态及其系统学意义

借助扫描电镜观察了南五味子属(Kadsura)中黑老虎(K.coccinea)、南五味子(K.japonica)和狭叶南五味子(K.angustifolia)雄花和雌花的形态发生过程, 三种植物花发育早期相似而发育后期出现分异。根据花形态发生早期的相似性, 支持南五味子属为单系起源;根据花形态发生后期的分异状态, 支持将南五味子属分为离蕊南五味子亚属(Subgenus Cosbaea)和南五味子亚属(Subgenus Kadsura)。借助扫描电镜观察了短梗南五味子(K.borneensis)和披针叶南五味子(K.lanceolata)花的形态, 将南五味子和狭叶南五味子的花与短梗南五味子和披针叶南五味子的花比较, 赞成在南五味子亚属下设南五味子组(Section Kadsura)和南洋南五味子组(Section Sarcocarpon)。根据在狭叶南五味子中观察到的两性花痕迹和在五味子属(Schisandra)东亚五味子(S.elongata)花中观察到的两性花, 本文认为现存五味子科(Schisandraceae )植物的单性花可能由具两性花结构的祖先演化而来。根据五味子科植物柱头与八角科(Illiciaceae)植物柱头的相似性, 不支持将五味子科从八角目(Illiciales)中分出而成立五味子目(Schisandrales)的观点。     

Terminal differentiation of the adipose tissue in relation to vitellogenesis in the cricket

Changes in fat body cell ultrastructure were followed in the female cricket during the first days of adult life (at the onset of vitellogenesis). Cytological evidence was obtained for the depletion of stored lipids, and correlative accumulation of glycogen, in connection with lipidic vitellogenesis. The production of glycoproteic yolk precursors is achieved by the adipose cells following a process of terminal differentiation which transforms into secretory cells. The whole process occurs within the four first days of adult life.     

Thiophene accumulation in relation to morphology in roots of Tagetes patula

Roots of marigold (Tagetes patula L.) accumulate thiophenes, heterocyclic sulfurous compounds with strong biocidal activity. In detached roots cultured in vitro, the thiophene content was 5 mol·(g fresh weight)^-1 which is 25-times higher than in roots attached to the plant. In roots derived from tissues transformed by Agrobacterium tumefaciens and A. rhizogenes, the morphology and thiophene content varied with the bacterial strain used. Transformation stimulated the elongation of the root tips and the formation of lateral roots but lowered the thiophene level to 20–50% relative to the concentration in untransformed detached roots. A negative correlation was found between the number of laterals in a root system and the thiophene content. Extensive branching and a decrease in thiophene accumulation was evoked in untransformed roots by indole-3-acetic acid (1–10 mol·l^-1) added to the medium. Within the roots, the highest thiophene concentrations were found in the tips. The results indicate that auxin directly or indirectly plays a role in the regulation of the thiophene level in root tips.Abbreviations B5 Gamborg's B5 medium - IAA Indole-3-acetic acid     

Responses of Pinus clausa, Pinus serotina and Pinus taeda seedlings to anaerobic solution culture. I. Changes in growth and root morphology

Seedlings of pond pine ( Pinus serotina Michx.), sand pine [ P. clausa (Engelm.) Sarg.] and two edaphic seed sources of loblolly pine ( P. taeda L., dry- and wet-site seed sources) were grown in non-circulating, continuously flowing solution culture under aerobic (250 μ M O₂) and anaerobic (≤ 23 μ M O₂) conditions. Survival was 100% for all seedlings at 11 weeks. Although shoot height, biomass and leaf emergence of loblolly and pond pine seedlings were not significantly affected by 15 or 30 days of anaerobic growth conditions, root biomass was significantly reduced. Sand pine suffered the largest reduction in biomass, showing extensive root dieback and shoot chlorosis with retarded leaf development. These anaerobically induced symptoms of flooding injury were less severe in dry-site loblolly pine, and absent in wet-site loblolly and pond pine seedlings. Adventitious or new, secondary roots, and stem or taproot lenticels were particularly abundant under the 30-day anaerobic treatment in wet-site loblolly and pond pine seedlings, present to a lesser degree in dry-site loblolly pine, and nearly absent in sand pine seedlings. These results indicate that much of the immediate damage from flooding is due to the anoxic condition of the root rather than to the build-up of phytotoxins or soil nutrient imbalances. On the basis of overall seedling vigor, root plasticity and growth, we suggest the following flooding-tolerance/intolerance species (seed source) gradient: pond pine ≥ wet-site loblolly pine > dry-site loblolly pine > sand pine.     

Sperm package morphology in scorpions and its relation to phylogeny

Sperm packages are widespread in the order Scorpiones, but absent in the family Buthidae. The morphology of sperm packages is diverse and apparently has phylogenetic information. The objectives of this work were to show diversity of sperm packages and to provide a quantitative basis for using sperm packages’ morphology as a taxonomic character. For this, we conducted a morphological analysis and comparison of the different sperm packages of species of the family Bothriuridae. The seminal content from males of species of Bothriuridae was studied. Specimens from Iuridae, Buthidae, Euscorpiidae, Liochelidae, Scorpionidae, Vaejovidae, Chaerilidae, and Chactidae were used for comparison. Digital images of sperm packages were measured and statistically analysed based on the following variables: total length, head width, head–body angle, total area, and head length. Pairs of variables were also contrasted, and all the variables were correlated with the current phylogenetic hypothesis for Bothriuridae. High morphological diversity and variability in measures was observed. In general, measurements were similar within each genus, but differed amongst genera. Cane‐like sperm packages are very common in species of the family Bothriuridae. Species from Bothriurus show a wide range of sperm package shapes, some of them shared with Timogenes and Vachonia species, supporting the idea of nonmonophyly of the genus. Many species showed sperm package dimorphism inside a single male. Some of the analysed features fit well with the phylogenetic hypothesis in Bothriuridae, and the general package shape shows high correlation with scorpion phylogeny in other families. Bent and round packages are the most common amongst the different families. Sperm packages are not developed in Chaerilidae, as in Buthidae. This is the first morphological and comparative analysis of sperm packages in scorpions, and reveals much greater diversity in this trait than previously known. Our results reinforce the idea that the study of morphology of sperm packages would contribute characters for scorpion phylogeny at different levels. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 463–483.     

Regulation of lipid synthesis in relation to keratinocyte differentiation capacity

Cultured keratinocytes and squamous carcinoma cells provide a useful model system for studying the processes involved in the regulation of differentiation, as the differentiation capacity of the cells can be modulated experimentally by changing the extracellular calcium concentration. Furthermore, the squamous carcinoma cell lines exhibit a defect in their differentiation capacity which they express to different extents. In this paper, the effect of external lipoproteins has been studied on lipid synthesis in normal keratinocytes and three squamous carcinoma cell (SCC) lines which showed a decreasing capacity to differentiate in the order of normal keratinocytes greater than SCC-12F2 greater than SCC-15 greater than SCC-4. The ability of the cells to form cornified envelopes was taken as a measure of differentiation capacity. The rate of total lipid synthesis as well as the phospholipid-neutral lipid ratio decreased in the order SCC-4 greater than SCC-15 greater than SCC-12F2 greater than or equal to normal keratinocytes, clearly correlating with the differentiation capacity of the cells. Because of the high rate of phospholipid synthesis and the low rate of ceramide synthesis, it is concluded that, under these in vitro conditions used, the maturation of keratinocytes proceeds to a lesser extent than that seen under in vivo conditions. In proliferating cells, in which the low-density lipoprotein (LDL) receptor is operative to a high extent, the rate of lipogenesis, especially that of neutral lipids, responded dramatically to changes of extracellular lipoprotein concentration. In the presence of lipoproteins a marked decrease of cholesterol and triacylglycerol synthesis and an increase of cholesterol ester synthesis has been observed. On the other hand, in differentiating cells lipogenesis appeared to be independent of extracellular lipoproteins, due to the absence of the LDL uptake mechanism, the only exception being the synthesis of triacylglycerols, the rate of which could be modulated to a certain extent by extracellular lipoproteins. The results presented here demonstrate a close inverse relationship between the regulation of lipogenesis by extracellular lipoproteins and the ability of the cells to differentiate.     

不同生长阶段马尾松生产力与气候因子的关系

林木生产力的大小与气候密切相关,掌握不同年龄阶段林木生产力与气候因子的关系对生产力预测及森林经营具有重要意义.本文利用1964-2011年温度、降水、相对湿度、日照时数等气象资料,结合气候湿润指数,运用树干解析数据,定量研究了马尾松生产力与气候因子的关系.结果表明:影响幼龄阶段、中龄阶段和近熟阶段马尾松单木生产力的气候因子各不相同,幼龄时期的单木生产力与3月相对湿度和1月的气候湿润状况显著相关;中龄阶段马尾松生长的限制因子为10月、7月高温和9月的日照时数,7月和5月的湿润状况对其生产力也有显著影响;近熟阶段马尾松生产力的大小与7月的降水量和湿润状况呈极显著正相关(P＜0.001).研究区域湿润温暖的气候基本满足了马尾松生长对水分和热量的要求,但生长中期的高温少雨限制了中龄阶段和近熟阶段马尾松单木生产力的增长.     

RFLP diversity in cultivated sorghum in relation to racial differentiation

Careful assessment of the comparative diversity for molecular markers and for potentially-useful morpho-agronomic traits is paramount to the analysis of a genome through the mapping of favorable genes. Sorghum (Sorghum bicolor ssp.bicolor) varieties are traditionally classified into five races on the basis of morphological traits, especially panicle and grain traits. Isozyme diversity has provided a new insight into genetic diversity, and showed a marked geographic structure. We performed RFLP analysis on 94 varieties, chosen to represent the main cross combinations (race × geographic origin), using 35 maize probes that detect polymorphism with at least one of the two restriction enzymesHindIII andXbaI. A total of 50 polymorphic probe-enzyme combinations yielded 158 polymorphic bands. The bicolor race appeared highly variable and included many rare markers. Among the other races multivariate analysis of the data differentiated six clusters corresponding, by decreasing magnitude of divergence, to: the margaritiferum types (a sub-race of race guinea); the guinea forms from western Africa; race caudatum; race durra; race kafir; and the guinea forms from southern Africa.The apparent geographic differentiation was related to the contrasting distribution of these races and to a higher similarity between races localized in southern Africa. The data agree with the current hypotheses on sorghum domestication but reveal associations between neutral markers and traits probably highly subjected to human selection. Whether such associations will be observed with other useful traits, and to what extent they are maintained by genetic linkage, is worth exploring.