Volume 99, Issue 3
June 1989, pages 165-300
pp 165-177 June 1989
The paper deals with 4 species ofBrigantiaea and 7 species ofLetrouitia known from India.Brigantiaea nigra is a new species to science.
pp 179-197 June 1989
This paper deals with a revised taxonomic study ofRotala species in peninsular India, where it displays maximum morphological diversity than in other parts of the subcontinent. Of the 19 species reported from India, 14 are distributed here. Besides, two new species of the genus,Rotala cookii Joseph and Sivarajan andRotala vasudevanii Joseph and Sivarajan have also been discovered and described from this part of the country, making the total number of species 16. An artificial key for the species, their nomenclature and synonymy, descriptions and other relevant notes are provided here.
pp 199-210 June 1989
Village ecosystem function of the Khasis in Meghalaya was studied. The land has been desertified around Cherrapunji as the traditional slash and burn agriculture (jhum) has been replaced by plantation systems. Apart from mixed plantations with areca nut, orange, jackfruit, bay leaf, black pepper and betel leaf, broom grass, thatch grass and bamboo are also raised in the village. All the systems generally are economically viable and have a high energy efficiency with labour as the major input. Poultry and swine husbandry are two animal husbandry systems in the village. Both are largely detritus based. About 9% of the produce from mixed areca nut plantation, 50% from the bamboo and entire produce of thatch grass is utilized within the village and the rest is exported. In the absence of agriculture much of the food for consumption is imported from outside the village boundary. The possibility of further useful changes needs evaluation with scientific inputs.
pp 211-221 June 1989
Energy and economic analysis of cash crops (coffee, tea, ginger and pineapple mixed cropping system) are contrasted with shifting agriculture under a 10-yr cycle in north-eastern India. Though ginger gave maximum monetary return, followed by tea, the output/input ratio was higher for pineapple mixed cropping system. Coffee is not successful in this area of study. Some of the cash crop systems had high energy efficiencies though the shifting agriculture had high output/input ratio of 43·5. Nutrient losses through water was high under cash crops with maximal losses under ginger; compared to shifting agriculture the losses were substantial. It is suggested that plantation crops should be sustained in the region basing it, to the extent possible, on the concept of recycling of organic wastes.
pp 223-239 June 1989
At Visakhapatnam (17°42′N-82°18′E)Zizyphus mauritiana Lam. blooms twice a year, once during September–January (first season) and again during March–June (second season). The flowers are compatible to geitono and xeno pollen. They are strongly protandrous and pass through distinct developmental stages. While the first 2 flowers of umbel are invariably complete, the succeeding ones either develop up to the male stage or continue through the female. The flowers in the 2 stages are more numerous in the first season than in the second. They decrease as the seasons progress. Two plant types occur. In one, the flowers anthese at 0600 h (early) and in the other at 1000 h (late). The stigmas of the late type receive pollen in the latter half of their receptive period, first from the early and then from the both. Those of the early type receive pollen of the late type in the beginning of receptive period, and in the last quarter first from the early and then of the both. A population with only one plant type has the stigmas receiving pollen in the last quarter of their receptive period. Pollen in the male stage and nectar in the female constitute the reward to the insect visitors that included bees, wasps, flies, ants and butterflies. The former 3 groups proved to be effecting pollination, among whichApis florea, Ceratina sp.,Trigona sp.,Ropalidia spatulata, Chrysomya megacephala andSarcophaga sp. are the major pollinators.
pp 241-246 June 1989
In the apiaries of the western Himalayan region (Kumaon and Garhwal hills) of Uttar Pradesh, the honey is harvested twice in a year i.e. in autumn and spring. Out of 12 spring samples of honey analysed, there are 10 unifloral and 2 multifloral samples. The dominant entomophilous pollen types in unifloral samples areBrassica, and Rosaceae-Prunus type. It has been suggested that the anemophilous pollen types namely,Alnus andRumex may be used as markers of honey samples originated from the Himalayan region. The data presented in the paper are useful in standardization of honey samples.
pp 247-251 June 1989
Circadian and seasonal periodicities of 10 fungal spore types common in the atmosphere of Madras city are described from data obtained by sampling air with a Burkard model of the Hirst spore trap for a period of one year. The periodicity ofNigrospora conformed to ‘post-dawn pattern’;Alternaria, Drechslera, Curvularia, Torula to ‘mid-day pattern’;Cladosporium andPericonia to ‘double peak pattern’;Ganoderma, Coprinus andLeptosphaeria to ‘night pattern’. Maximum incidence of the spores were noticed in the atmosphere during August to December corresponding with the rainy season.
pp 253-258 June 1989
Flavonoids and related phenolics in the leaves of 14 conifers were studied and their relevance in the taxonomy of the group was assessed. It is found that biflavones were absent from the Pinaceae and Taxaceae. The former family was also devoid of flavones and possessed a low frequency of incidence of flavonols. The entire flavonoid systems was absent inPinus. In the light of these chemical evidences the identities of the Pinaceae and Taxaceae as separate orders Pinales and Taxales, are defended. The rest of the conifers are grouped in a new order, the Cupressales. The merger of Taxodiaceae and Cupressaceae is strongly opposed. Incorporating all the taxonomic evidences a new scheme of classification is proposed.
pp 259-264 June 1989
The distribution of different chemical constituents in 6 species ofGardenia is numerically analysed. The quantified chemical data show that the taxa studied are closely related and suggest that they could be divided into 4 clusters. Based on the established criteria of simplicity and complexity in biosynthetic pathways, rarity and ubiquity in distribution of the chemical constituents and/or correlation studiesGardenia longistyla, Gardenia resinifera andGardenia thumbergia have tentatively been found to be relatively advanced over the other 3.
pp 265-269 June 1989
Rhizolex 50 WP O,O-dimethyl-O(2,6-dichloro-4-methyl-phenyl)-phosphorothioate, a new fungicide, was evaluated againstSclerotium rolfsii Sacc., the causal organism of foot rot of betelvine (Piper betle L.). The fungicide,in vitro, arrested mycelial growth and sclerotial germination ofSclerotium rolfsii at 50 ppm and above concentration, maximum effect being at 100 and 200 ppm for inhibition of mycelial growth and Sclerotial germination respectively. Two months old potted betelvine plants were inoculated with mycelial culture ofSclerotium rolfsii by soil mixing method. Fungicide was applied by drenching method in desired concentration and on desired date. Fungicide treated pots showed lower percentage of vine mortality than the check (no fungicide). There was no significant difference in per cent mortality of vines under 0·2 and 0·4% fungicide applied at same date however higher dose (0·4%) of fungicide applied at 2 days after inoculation had shown lower percentage of vine mortality as compared to the lower dose (0·2%) at 5 days after inoculation. Thus, both concentration of Rhizolex 50 WP and time of its application play an important role in the control of foot rot disease of betelvine.
pp 271-278 June 1989
The sensitivity ofTriticale hexaploide cv. Panda-6 to 320 and 667 μg m−3 SO2 has been studied. Plant growth in terms of plant height, shoot and root length, number of leaves, roots and tillers and biomass per plant were reduced significantly in 320 and 667 μg m−3 SO2 respectively. The leaves of 90-day old plants were analysed in terms of leaf area injury per cent, leaf area reduction per cent, absorbic acid, leaf extract pH, phosphorus, sulphur and carbohydrate contents. Appreciable reductions in dry weight fractions and net primary productivity of SO2 treated plants were observed and the effects were concentration dependent. Chlorophylla, chlorophyllb and total chlorophyll contents of leaves were also reduced after 15 days to fumigation. The loss was higher in chlorophylla than chlorophyllb. Flowering and spike maturation were slightly advanced in both concentrations and 667 μg m−3 SO2 caused 22·11% reduction in weight of 100 grains.
pp 279-285 June 1989
Growth pattern of 3 common fresh water algaeChlorella, Scenedesmus andSpirulina was studied under the influence of organochlorine pesticide DDT, under laboratory conditions.Scenedesmus was found to be sensitive to DDT doses and growth was inhibited maximally up to 42% after 96h at 5ppm concentration. This alga shows phenotypic variations also in its colony structure at 3 ppm concentration.Chlorella andSpirulina are found to be highly tolerant and no growth inhibition is recorded at all doses of DDT. On the other hand, growth of these algae is promoted over that of control under the influence of DDT.
pp 287-292 June 1989
Observations on the protein content in 3 tropical salt marsh species viz.,Avicennia marina, Arthrocnemum indicum andHeleochloa setulosa showed 7·3–22·8% of alkali soluble proteins in vegetative parts and their maximum concentrations was during summer. The ethanol and water soluble proteins occurred in lower concentrations than alkali soluble proteins and their content did not vary during monsoon, winter and summer. Alanine, aspartic acid, glutamic acid, glycine, methionine, phenylalanine, serine and valine occurred in greater quantity than cystine, glutamine, isoleucine, leucine and threonine. Accumulation of proline was quite high inHeleochloa but it was not detected inArthrocnemum andAvicennia. Similarly, arginine was absent inAvicennia and its concentration in two other species was low. Seasonal changes indicated maximum accumulation of most of the amino acids inAvicennia in summer and inArthrocnemum andHeleochloa in monsoon.
pp 293-295 June 1989
Callus cultures were established on Linsmaier and Skoog’s medium supplemented with 2 mg/l 2,4-dichlorophenoxy acetic acid from seedling roots of two maize genotypes, known to have either cyanidin or pelargonidin in the aleurone. Coloured sectors were observed on the calli and regenerated roots.Rfvalues and absorption maxima of anthocyanin pigments fromin vitro cultures were similar to those from the aleurones of the respective genotypes.
pp 297-300 June 1989
The almonds, cultivated in Kashmir, on the basis of relative time of flowering reveal early-, mid- and late flowering types. The late blooming types hold key to the isolation of lines that can escape the damage of spring-rains. Anther dehiscence and stigma receptivity overlap creating conditions suited to self-pollination which is however obviated by self-incompatibility.