Volume 90, Issue 6
December 1981, pages 499-559
pp 499-508 December 1981
Seeds of fourteen species ofLindernia All., from South India were studied by scanning electron microscopy as to their surface ultrastructure. Results show some correspondence with the subgeneric classification proposed by Philcox. Seeds are broadly of two types, ribbed and unribbed. Sect.Bonnaya is rather homogeneous having unribbed seeds whereas all other sections studied possess prominently or faintly ribbed seeds. The ornamentation patterns however, do not give such a correlation. The seedcoat surfaces are either foveolate or pitted and with minute excrescences of different kinds—granular, fibrillar, filamentous or dagger-shaped. Taxonomic implications of the characters in the investigated species are discussed.
pp 509-514 December 1981
The paper correlates the laying of eggs, feeding habits and digestive capacity of the larvae of a butterfly identified asEuchrysops pandava Horsfield with the structural features and growth of leaves of some species ofCycas.
Analysis of faecal pellets of larvae yielded undigested fragments of lower cuticles transfusion tissue, and tracheids of leaves of the respective species. Speculations are made about attributing pest coprolites to insect larvae.
pp 515-520 December 1981
A field experiment was conducted with barley (Hordeum vulgare L. CV. BG 25) on sandy loam soil during 1978–79 at Haryana Agricultural University, Hissar (India). The results of the experiment revealed that the light intensity, temperature and stomatal conductance decreased, while the leaf water potential increased from flag to the lower leaves in the canopy. The irrigated barley showed a lower leaf temperature, higher leaf water potential and a greater stomatal conductance than unirrigated barley. The relationships between light intensity and stomatal conductance are discussed.
pp 521-533 December 1981
The structure and ontogeny of normal and abnormal stomata in the seedlings of 16 species of the Cruciferae have been presented. The mature stomata are anomocytic, paracytic, anisocytic, helicocytic and with a single subsidiary cell. The ontogeny of the anisocytic, paracytic, helicocytic and stoma with a single subsidiary cell conforms to the syndetocheilic or mesogenous, while that of anomocytic to haplocheilic or perigenous type. Several types of aberrant stomatal formations such as: single guard cell; contiguoas single-guard cells; contiguous stomatal; degeneration of guard cell/s; persistert stomatal cell; amitotic division of guard mother cell nucleus followed by pore formation; stoma with double pores; binucleate guard cell; division of guard cell; incomplete stoma with unequal guard cells; cytoplasmic connection; ring-shaped division of guard mother cell and uncommon wall thickening have been noticed. Aberrant stomatal developments are naturally occurring and not induced.
pp 535-539 December 1981
Gloeosporium ampelophagum andColletotrichum capsici were trainedin vitro for development of resistance to different fungicides. In general, the resistance developed by both the fungi was of low order ever after 10–14 generations of training.G. ampelophagum developed two-fold resistance to fentin and wettable ceresan, four-fold resistance to zineb and copper sulphate and 200-fold resistance to ziram. The resistance developed to ziram did not persist throughout the training period.Colletotrichum capsici acquired two-fold resistance to zineb and copper sulphate and two and a half-fold resistance to mercuric chloride.
pp 541-546 December 1981
The anatomical development of adventitious buds in the tuberous roots ofIpomoea batatas has been studied. Only the detached tubers regenerate. The bud primordia develop from the procambium-like cells adjoining lateral root scars. Initially, the buds grow away from the surface of the tuber but, later, they turn almost 180°, towards the surface of the tuber, before bursting out of the tuber. The growth of the bud is largely contributed by random periclinal divisions of parenchymatous cells of the bud primordium. The basipetally developed vasculature of the bud is connected to the vasculature of the lateral root.
pp 547-553 December 1981
The seeds ofDuabanga sonneratioides Ham. were found to be positively photoblastic and gave fast and maximum germination of 80% in cortinuous light but failed to germinate in the dork. Longer photoperiod favoured germination. Total length of exposure to light rather than the dark period determined the germination of the seeds. Higher temperature favoured germination at a given light exposure treatment. In the field, seeds up to a depth of 2 mm in the soil could germinate. These results have been related to the light demanding nature of this carly suceessional tree species.
pp 555-559 December 1981
Twelve germplasm cultivars of pigeon pea were screened for their tolerance to salinity during germination and early seedling growth. Germination, seedling growth and studies on proteins, nucleic acids (RNA and DNA) and free proline accumulation indicated that the cultivars ICP 7035 and 7065 showed high degree of tolerance to 0·4% salinity. These two tolerant cultivars showed lowered derangements in their metabolism and thus showed higher levels of proteins, nucleic acids and free proline than the other cultivars studied, indicating their adaptability to 0·4% salinity.