STRUCTURAL STUDIES ON THE GALACTOMANNANS OF LICHENS OF THE GENUSCLADONIA

Galactomannans were isolated fromCladonia signata,C. furcata,C. imperialis, andC. clathratavia successive alkaline extraction and precipitation with Fehling solution and Cetavlon. They were investigated using¹³C-NMR spectroscopy, methylation analysis, and Smith degradation, and their specific rotations and monosaccharide compositions determined. As with galactomannans of otherCladoniaspecies, they contained (1→6)-linked main chains of α-mannopyranose, which were non-substituted (structure4in Fig. 2), mono-substituted at O-2 with α-mannopyranose (structure6) or α-galactopyranose (structure1), O-4 with β-galactopyranose (structure2), and disubstituted at O-2 and O-4 with α-mannopyranosyl and β-galactopyranosyl units, respectively (structure5). Disubstitution was present to a greater extent in the galactomannans ofC. clathrataandC. imperialisthan in those ofC. signataandC. furcata. In the case of the galactomannans ofC. furcata,C. clathrata, andC. imperialis, substitution also occurred at O-2 withO-β-galactofuranosyl-(1→6)-O-α-mannopyranosyl units (structure7). As observed in previous investigations, the C-1 portion of the¹³C-NMR of mannose-containing polysaccharides is typical of the lichen species. However, those of galactomannans ofC. imperialisandC. clathrataare almost identical and, although other chemical data showed many structures in common, some differences were evident.     

THE EFFECT OF MCPA AND 2:4-D HERBICIDES ON THE QUALITY OF SPRING OATS FOR MILLING AND PROVENDER FEEDING

MCPA applied to oats at the 1- to 2-leaf stage had slight effects on grain quality, whereas 2:4-D at this stage generally increased kernel weight, husk ash content, and content of abnormal grains, and decreased the grain yield. Applied at the 4- to 5-leaf stage, 2:4-D also increased kernel nitrogen content and decreased kernel oil content. Effects were enhanced as the dosage increased. Yielder and Craigs Afterlea were most susceptible to 2:4-D at the 4- to 5-leaf stage; Sun II, a relatively resistant variety, at the 6- to 7-leaf stage.     

几种农艺因素影响小麦籽粒蛋白质含量的数学模型研究

用二次回归旋转组合设计研究了基本亩数（X_1）、基苗氮肥（X_2）、孕穗期氮肥（X_3)、过磷酸钙（X_4）和氯化钾（X_5）用量对小麦籽粒蛋白质含量的影响．结果表明,X_4、X_1和X_2对蛋白质含量有显著作用,因素之间存在着复杂的互作效应．利用计算机模拟选优,获得了本试验条件下蛋白质含量大于13％的5个农艺因素组合方案,X_1=172.35～186.75万／ha;x_2=116.6～123.6kg／ha;x_3=33.75～39.15kg／ha;x_4=333.9～448.8kg／ha;x_5=190.65～233.10kg／ha．     

应用除莠剂消灭已衰退的子莲种群的初步试验

更新已衰退的子莲种群,是当前植莲生产上需要解决的一个问题。作者通过应用除莠剂消灭莲群的试验,基本上解决了这个问题。莲荷对苯氧乙酸类除莠剂相当敏感。每亩用0.15—0.25市斤的72%2,4-滴丁酯乳油作茎叶喷雾处理,就可彻底“灭荷绝藕”,且对鱼类及其食料生物无不良影响。从子莲进入营养生长盛期起,至盛花期(结藕前)止,均为施药适期。本法对劳力少,且需大面积彻底更新子莲种群或清除野莲的植莲单位,最为适用。       

秦岭南坡地衣植物研究初报

报道了采自于秦岭南坡的地衣植物21种,隶属于11科、11属。     

ENVIRONMENTAL FACTORS AFFECTING THE DISTRIBUTION OF LICHENS ON GRANITIC MONUMENTS IN THE IBERIAN PENINSULA

The phytosociology of lichens colonizing granitic churches and dolmens in Galicia (N.W. Spain) and Alentejo (central Portugal) was studied so as to identify (a) a group of species whose frequency on these structures would make them potentially useful as test species for the evaluation of biocides used for conservation, (b) environmental factors likely to control species distribution, and (c) species that may be useful as bioindicators of environmental factors in this kind of construction in the region studied. Chief among the factors correlating with species distribution is the class of structure (church or dolmen), which is attributed to the probable influence of this factor on environmental parameters affected by structural complexity, the presence of non-granitic materials and the influence of man in the immediate surroundings. The bioindicator species most sensitive to this complex of parameters appear to be three species found only on churches (Caloplaca citrina , Sarcogyne clavus and Verrucaria macrostoma) and the most widespread of the species found only on dolmens (Lasallia pustulata). Other important factors, probably affecting the influence of class of structure, are pH and the availability of nitrogen and moisture.