Indica Var Research Articles

MOSAIC DISEASE OF Stachytarpheta indica VAHL., A SOURCE OF VIRUS INFECTION TO CROP PLANTS

Stachytarpheta indica Vahl., a common verbenaceous weed in Kerala, was observed to be infected with a severe mosaic disease. The virus was easily transmitted by wedge grafting, sap inoculation and by the aphids, Aphis craccivora Koch.and Aphis gossypii Glov. The virus had a dilution end point (DEP) of 1: 750 1: 1000, thermal inactivation point (TIP) of 70-75°C end longevity in vitro (LIV) at room temperature (27-32°C) 48-72 h, and at refrigerated condition (5-10°C) 96-120 h. In the host range studies the virus infected seven test plants viz., Benincasa hispida, Cucumis sativus, Cucurbita maxima, Trichosanthes anguina (Cucurbitaceae), Nicotiana tabacum var. White Burley, Nicotiana tabacum var. Samsun (Solanaceae) and Stachytarpheta indica var. jamaicensis (Verbenaceae). Results of the studies on transmission, physical properties and host range of the virus indicated that this might possibly be a strain of Cucumis virus I.

Pellatispira (Foraminiferida) From the Upper Eocene of Surat-Broach, Gujarat

Abstract The foraminiferal genus Pellatispira Boussac is represented by P. crassicolumnata Umbgrove in the Upper Eocene succession of Surat-Broach, Gujarat. The morphology of the species is described and illustrated. The specimens from Surat-Broach originally identified by Rao as Pellatispira inflata Umbgrove var. minor var. nov., P. madaraszi (Hantken) var. indica var. nov. and P. orbitoidea (Provale) are considered to fall within the range of variation of P. crassicolumnata Umbgrove. An analysis of the external and internal structures indicates that the genus Pellatispira is distinct from the typical members of the Calcarinidae, Miscellaneidae and Nummulitidae. It is best retained in the family Pellatispiridae Hanzawa.

On a new variety of Geminella planctonica (Balachonzew) comb. nov. (Chlorophyceae, Ulotrichales)

Abstract The structure and reproduction of a new variety, Geminella planctonica (Balachonzew) comb. nov. (= Gloeotila planctonica Balachonzew) var. indica var. nov. isolated from a planktonic growth in paddy fields of Soraon, Allahabad (India), have been described. The new form is distinct in its measurements, and in having a broader and more consistent sheath as compared to the type species.

Growth Responses of Rice Plant to Environmental Conditions : I. The effects of air-temperatures on the growth at vegetative stage

A japonica var. Norin-17 and a indica var. IR-8 were grown in the growth chambers at 35-30, 30-25, 25-20, 20-15, 15-10°C day (12 hr)-night (12 hr) temperatures, respectively, under natural light intensity. Three times of sampling were taken at 10 days interval. The results obtained are as follows. 1) Plant height and leaf emergence rate were higher with the higher temperatures. The optimum temperature for tillering was a little lower than for plant height and dry matter production, the tillering ability (tiller number/leaf number of main stem) being highest at 25-20°C. 2) The dry matter production was greatest at 30-25° at the early growth period for both varieties, being followed by 25-20, 35-30, 20-15 and 15-10°C in order. At the later stages, the growth at 25-20° gradually increased, subsequently becoming highest in IR-8. 35-30° seemed to be too high for growth and the lower temperatures than 20- 15° significantly decreased growth. In the regime of this experiment, the optimum for growth were 25-30° day and 20-25° night temperatures. 3) T/R and LB/LS ratios decreased with the decrease of temperature, with the exception of 15-10° where T/R ratio was higher. 4) Leaf number and leaf area per plant changed parallel with the dry matter production. The density thickness of leaf increased with decrease of temperature. The dry matter percentage of leaf was low at the optimum temperature for growth. 5) RGR of rice plant was controlled firstly through RLGR and secondly through NAR, both being declined with the advancement of growth especially sharply when the temperature increased. 6) The growth of IR-8 was greater than Norin-17, probably due to its greater seed size and greater seedling at the start of experiment, since RLGR and NAR during the temperature treatments were not significantly higher in the former variety.

NITROGEN FIXATION BY BEIJERINCKIA IN RELATION TO SLIME FORMATION.

Results of studies of nitrogen fixation and slime formation in Derx's medium by sixteen strains of Beijerinckia indica showed that the amounts of nitrogen fixed at different periods were related positively and significantly with the amount of slime formed. From the rates of increase in nitrogen fixation with increase in slime formation the strains could be divided into two groups corresponding to (1) Beijerinckia indica with an average rate of increase of 0.066±0.003 and to (2) Beijerinckia indica var. alba with an average rate of increase of 0.132±0.010.

Some Characteristics of the Oriental Honeybee, Apis indica F., in China

The Oriental Honeybee (Apis indica Fabricius), found throughout Japan, China, India, The Philippine Islands, Indo-China and the Malay Region, is one of the native honeybees of the Oriental Realm and, until the recent introduction of Apis mellifera L. from abroad, has been the main source of honey in these countries. From studies by the writer on specimens of these bees from the countries mentioned above, it is apparent that the largest individuals of this species occur in Fukien Province, in Southeastern China. These bees were identified as Apis indica var. peroni by Dr. T. Sonan, of the Government Research Institute in Taihoku, Formosa. Unless otherwise noted, the studies reported in this paper refer to this variety of Apis indica.

Specialization in Sphaerotheca fuliginea (SCHLECHT.) POLL

Specialization in Sphaerotheca fuliginea (SCHLECHT.) POLL. parasitic on various plants in Formosa was studied by inoculation experiments as well as by comparing the morphological characters of the conidia. So far as the present experiments are concerned, the following six biological species can be distinguished inter se.A. Conidia with an average length of 29μ1. Parasitic on Balsam (Impatiens Balsamina)B. Conidia with an average length of 32μa. Conidia with an average width of 18μ2. Parasitic on Cucurbitaceae3. Parasitic on Lactuca indica var. dracoglossa and related speciesb. Conidia with an average width of 20μ4. Parasitic on egg plant (Solanum Melongena)5. Parasitic on Hibiscus mutabilisC. Conidia with an average length of 36μ6. Parasitic on Emilia sonchifolia

Variation in the Ray-flowers of some Compositae

Quantitative studies were made upon the rays of three species of Compositæ, viz. Arnica unalaschensis in Mt. Hakkoda, Aster trinervius var. congestus and Asteromæa indica var. pinnatifida in Aomori.In the Arnica, on account of its single-headedness, the difference of flowering season, together with the meristic change of rays, was determined by the external conditions, but in the latter two, the internal factors seemed to have played the principal rôle on it, and in the Aster no seasonal fall was seen in the first one month.The series of Fibonacci hold some stability in the appearance of mode, and the occurrence of variates on some classes is more improbable than on other classes.