Volume 43, Issue 1
January 1956, pages 1-87
pp 1-8 January 1956
1. Three species of Glœosporium were isolated from guava, lime and citron twigs. Their behaviour towards the mixture of various compounds of carbon were not similar.
2.G. psidii andG. limetticolum grew significantly better on any combination of galactose, raffinose and sorbitol whileG. citricolum supported less growth than on their individual sources. Mannitol alone supported best growth ofG. citricolum but it could produce excellent growth ofG. psidii when it was mixed with raffinose.
3. Excellent sporulation ofG. psidii was observed on a combination of all the four carbon substances, that ofG. citricolum on a mixture of raffinose and galactose or sorbitol and galactose.G. limetticolum gave best sporulation on raffinose alone.
pp 9-22 January 1956
pp 23-31 January 1956
1. Freshly emerged imagines ofPapilio demoleus, which had no previous experience with colour, were kept in a large cage devoid of any coloured object apart from those specially provided for the experiments.
2. These were offered artificial coloured flowers prepared from the standardized Ostwald series.
3. On the coloured flowers, the inexperienced unfed specimens showed a characteristic feeding response: they approached the artificial flower in flight, landed on it and unrolled their tongues with which they performed probing and sucking movements on the paper.
4. The results clearly show thatPapilio demoleus in the feeding state, is mainly attracted to the blue and purple colours while the yellow, yellowish-green, green and blue-green colours are completely neglected.
5. Thus, they have provided a proof that certain insects, contrary to Forel’s assumption (1910), show not only acquired but also inborn or spontaneous preferences for colours.
pp 32-36 January 1956
An account of the results of experiments regarding overcrowding of aphids on plants and subjection of aphids to darkness as factors in the wing development of aphidsMacrosiphum jaceæ is given.
It is observed that poor nutrition due to overcrowding induces to a large extent wing development in aphids.
Subjection of aphids to increasing hours of darkness did not produce winged forms of aphids.
pp 37-45 January 1956
A close affinity ofCajanus indicus Spreng. with certain erect species ofAtylosia particularlyA. lineata W. & A. andA. sericea Benth., is indicated on morphological, taxonomical and cytogenetical grounds as also from the homology of some normal and mutant characters in the two genera and high fertility of certain inter-generic hybrids.A. lineata andA. sericea have the same chromosome numbers asCajanus indicus (2n=22).A. lineata andA. sericea are highly resistant toTur pod-boarer (Exelaster atomosa, W.) andTur wilt disease caused byFusarium udum Butler.
Besides the utility ofAtylosia species as a soil conserving leguminous forage cover crop, they can be utilised for evolving superior strains of cultivatedCajanus indicus combining hardiness, perennial growth habit, tolerance to summer drought on poor eroded soils and high degree of resistance to certain pests and diseases.
Occurrence of only a single reported species ofCajanus in India imposes certain limitations on the scope for its improvement through breeding. The evidence regarding its close affinity with certain erect species ofAtylosia opens fresh avenues for breeding and improvement ofTur, which is one of the most important grain pulse crops of India.
In the light of evidence for their close affinity, it is suggested that erect stem species ofAtylosia may be incorporated in the genusCajanus and the two genera may be taxonomically revised.
pp 46-54 January 1956
A detailed investigation has been carried out on the mode of action of the anticoagulant factor present in the latex ofCarica papaya.
The dual function of the anticoagulant factor,viz., the inhibition of the conversion of prothrombin to thrombin, and the destruction of thrombin activity has been established.
It has been found that the iodacetate treatment destroys the antithrombin activity of the anticoagulant factor. However, the iodacetatetreated anticoagulant factor inhibits the formation of a perfect fibrin clot from plasma, even in the presence of active thrombin, probably through complex formation with the fibrinogen of the plasma. The possibility of the presence of a co-factor in plasma which promotes this complex formation is also envisaged.
pp 55-61 January 1956
The paper deals with investigations on the stylar end rot of guava fruits. Fruits in the orchard as well as in storage suffer with this disease, which is, however, of rare occurrence. The symptoms of the disease have been described in detail.
A species ofPhomopsis was constantly associated with this rot and later pathogenicity tests proved this fungus to be the causal organism.
While some infection was obtained through uninjured surface, injury favoured infection. Apart from stylar end rot the fungus was able to cause fruit rot in general.
The morphology of the fungus has been described and its temperature relationship has been studied. The fungus had a minimum temperature for growth near 10° C., an optimum near 25° C. and a maximum of about 35° C.
pp 62-66 January 1956
1. The action of lead on the excitatory and contractile mechanism of smooth muscle is described. The latter has been determined by testing the effect of lead on dying and heat killed muscles.
2. Lead causes contraction of smooth muscle and arterioles by direct action on the contractile mechanism. This action may be of significance in producing contraction of smooth muscle in the body and in producing hypertension.
pp 67-71 January 1956
pp 72-87 January 1956