Volume 92, Issue 1
February 1983, pages 1-79
pp 1-4 February 1983
Cylindrocolea tagawae (Kitag.) Schust., so far endemic to Thailand, has been described for the first time in Indian bryoflora. The taxonomic details along with the variations observed in Indian plants have been provided.
pp 5-18 February 1983
Sporogeneses, development of gametophytes, endosperm and embryo ofMecardonia procumbens (Miller) Small have been described. The wall of the microsporangium consists of an epidermis, an endothecium, a middle layer and a glandular tapetum. The development of the anther conforms to the dicotyledonous type. The tapetal cells become binucleate and the endothecial cells acquire fibrous thickenings in later stages. Quadripartition of the microspore mother cells is simultaneous. Pollen grains are shed at two-celled stage and are tricolpate. Development of the female gametophyte is of Polygonum type. Middle part of the gametophyte is surrounded by an endothelium. Endosperm is ofab initio cellular type. Chalazal and micropylar haustoria are organised. Both the micropylar and chalazal haustoria are four-celled and this is the first report in the tribe Gratioleae. Embryo development is of Onagrad type. The cell ‘d’ functions as the hypophyseal cell.
pp 19-22 February 1983
The paper gives an illustrated account of a new grassviz. I. swaninathanii from India.
pp 23-28 February 1983
Dalbergia beddomei andDerris kingdonwardü are described as new to science.Dalbergia kingiana Prain is reported from Burma for the first time after its type collection from Kachin Hills. The collection ofD. psuedo-sissoo Miq. from Thirunelveli Hills, South India represents a rare species. The pod characters ofDerris ovalifolia Wt. are given for the first time.
pp 29-34 February 1983
Pollen morphology of seven species ofCapparis L., has been studied using light microscope and scanning electron microscope. Ultra surface patterns coupled with endocolpium characters of pollen grains are useful for distinguishing the species.
pp 35-39 February 1983
The observations recorded from over one thousand protein extractions from the forage plant lucerne, cultivated under different field conditions from 1969 to 1981, were subjected to statistical analysis to study the extractability of protein through simple mathematical equations. Among the nine parameters considered, the whole-crop dry-matter percentage had a major influence on the proportion of the fresh crop that remain as the fiber feedstuff for ruminants after the juice extraction. The total and protein N extractability from plant was closely related with the amount of fiber fraction, and the dry matter contents of fresh crop and fiber. Regression equations enable predicting the efficiency of protein extraction from a forage crop before processing it for production of protein.
pp 41-49 February 1983
Debladed petioles of pot cultured plants, entrained into one-stemmed habit and two-stemmed habit of PN-46-A and Pusa jwala varieties of Chilli (Capsicum annuum L.) were treated with lanolin+growth hormone emulsion. It was observed that morphactin, cytokinin and auxin retarded petiolar abscission in both the varieties and methods while ethylene, gibberellin, abscisic acid and ascorbic acid accelerated the abscission of all the petioles tested for the purpose. Relative merits and demerits of the methods used are discussed in relation to alternate leaf arrangement in the present experimental plant material.
pp 51-79 February 1983
The introduction of chromosome banding techniques for linear differentiation of chromosomes have allowed the identification of the heterochromatic segments on the chromosomes. These heterochromatic segments are primarily composed of repetitive DNA, which are discernible in the form of dark staining regions by Giemsa C band staining or exhibit enhanced or reduced fluorescent bands by Q banding techniques depending upon the particular type of DNA repetition. The analyses of banding patterns have allowed in plants, the identification of chromosomes or parts of chromosomes, which have been utilized for inter- and intra-species comparisons. Based on the information of banding patterns, amount and distribution of heterochromatic segments, coupled with karyotypic features and morphological similarities; the probable phylogenetic relationships in various plant taxa from Gymnosperms, Angiosperms (both dicots and monocots) have been suggested. The information on heterochromatin recognition have also been utilized in suggesting probable ancestry of polyploids and the trend of evolution in varietal differentiation and speciation. Analysing the data, a probable phylogenetic significance and the direction of change in heterochromatin evolution in plants is suggested.