保山地区碱性温泉中的高温菌

保山地区位于云南省西部,是全省温泉分布比较密集的地区之一。温泉作为地热资源已引起有关部门的重视,70年代已进行了地热资源的调查和开发利用研究。但是对于温泉中潜在的高温菌资源,尚未进行过系统考察、研究。现将我们对于保山地区pH8.0以上的高温温泉中的高温菌研究结果报告于后。       

OBSERVATIONS ON THE INCIDENCE OF CLUB-ROOT DISEASE OF BRASSICAE IN LIMED SOILS IN RELATION TO TEMPERATURE

When cabbage plants growing in artificially contaminated, heavily limed soil were maintained at greenhouse temperatures (mean about 23 C.) for periods of up to 12 days and then at shade temperatures in an open-air verandah (mean not exceeding 12.5 C.) for up to 21 days only slight attacks of club root developed. Exposure to greenhouse temperatures for at least 6 days and then in a verandah to a mean air temperature of about 16 C. permitted severe attacks to develop. A very severe attack occurred when plants remained in the greenhouse throughout an experiment, but all the plants were healthy when verandah temperatures only were employed.
It is suggested that exposure to favourable temperatures for infection and development of the disease for 12 hr. daily may permit the occurrence of a moderately severe attack.     

THE INCIDENCE AND ORIGIN OF SPOTTED PATTERNS IN THE ESTRILDIDAE

The plumage of the Estrildidae was examined in order to determine the incidence and origin of the spotted patterns.
In the Australian grassfinches a series of feathers showing the derivation of spotted patterns from transverse barring was found in two species. In most species such patterns consisted of single broad spots, but in two species paired spots were present.
The mannikins show three types of spotted pattern. One is derived from transverse barring, another from a rachial streak, and the third from a combination of both bars and streaks. The last one is not a true spotted pattern, the effect being due to overlapping feathers.
The waxbills show spotted patterns derived from transverse barring, the development of which exactly parallels that shown by the grassfinches, but differs in that almost all patterns show paired spots.
The spotted patterns appear to have been derived from a basic barred pattern in most cases, and to represent an increasing complexity of pattern rather than a gradual loss.
It is considered that similar patterns in widely separated species are due to parallel evolution of patterns and not to phylogenetically close relationship.
Where various species show different successive stages in the evolution of a pattern, this does not indicate that one is ancestral to another. Since the species concerned have a common family relationship, the potential for such a pattern may be present throughout the family.
Since the patterns have a function in specific recognition, it is suggested that similar patterns are likely to recur in widely separated localities and that the patterns of sympatric species are likely to differ. If similar patterns are present in one area they will probably indicate close relationship.
The inference of this in relation to plumage pattern problems in some other orders is briefly discussed.     

A NOTE ON THE ENUMERATION OF THERMOPHILIC SULPHATE-REDUCING BACTERIA (CLOSTRIDIUM NIGRIFICANS)

SUMMARY: The established techniques for counting mesophilic sulphate-reducing bacteria were inadequate for counting Clostridium nigrificans . Attempts to improve the viable counts by using different reducing agents and by altering the basal medium achieved only limited success.     

THE INCIDENCE AND CONTROL OF CAULIFLOWER MOSAIC IN BROCCOLI IN SOUTH-WEST ENGLAND

Cauliflower mosaic in south-west England is most prevalent where there is a sequence of brassica crops that overlap in time. Broccoli yields can be increased by using plants raised in seed-beds separated by half a mile from old infected plants. Surrounding seed-beds with crops of kale or barley decreased the incidence of mosaic even when the seed-beds were only 5 yd. from infected plants.
Most plants infected at harvest contract infection after transplanting. A plant infected in the seed-bed or early in the growing season can produce a group of infected plants immediately around it, and almost as many farther away. Spread can occur in the same pattern from these secondarily infected plants.
Loss of yield is correlated with the time plants are infected. Plants infected as seedlings produce little or no curd or seed, whereas those infected when nearing maturity yield almost as well as uninfected plants.
The movement of alate aphids is positively correlated with the numbers of infectedplants, and symptoms in field plants generally appear 8–9 weeks after infection.
Cauliflower mosaic virus occurs in strains distinguishable by the severity of symptoms they cause.