Massey Documents by Type

Permanent URI for this communityhttps://mro.massey.ac.nz/handle/10179/294

Browse

Subject: search.filters.subject.Roots (Botany)

Search Results

Now showing 1 - 7 of 7
  • Thumbnail Image
    Item
    A study of the early development of the root systems of various grass species, and, a study of the importance of various roots, particularly the seminal roots to Lolium perenne : thesis submitted in part fulfilment for the degree of Master of Agricultural Science in Plant Husbandry, University of New Zealand
    (Massey University, 1950) Yates, Milton Earle
    New Zealand is essentially a land of pasture. Greater reliance is placed on pastures for the sustenance of stock by the farmer in New Zealand than probably anywhere else in the World. The study of pastures is theretore of paramount importance to the national welfare of New Zealand and their improvement will be reflected in raised living standards and at the same will provide more food for the hungry world of today. There is no doubt that New Zealand is favoured by an equable climate and well distrtbuted rainfall which enables her to derive a considerable portion of her wealth trom grasslands. Nevertheless we have had to adopt farming methods to suit the environment so that the greatest benefits may be derived from the natural advantages with which New Zealand is endowed. New Zealand has proceeded a long way since the early days of her farming when little was known of the environmental requirements of individual species in order that they may produce to their maximum. It is unquestionable that much of the progress already made in grassland husbandry in this country is due to the wide range of trials conducted by the Department of Agriculture and Grasslands Division, D.S.and I.R., particularly over the last quarter of a century. Much has been learnt in the past and investigations being pursued at the present time will no doubt be reflected by improved methods of grassland husbandry with consequent increased pasture production in the future. [From Introduction]
  • Thumbnail Image
    Item
    The role of the roots of some grass and clover species in the improvement of the soil structure of a Tokomaru silt loam : a thesis presented at Massey Agricultural College in part fulfilment of the requirements for the degree of Master of Agricultural Science, University of New Zealand
    (Massey University, 1955) Robinson, George Stewart
    It has been long been realised that grassland has a beneficial effect on the fertility of soil. This is not only the case with the natural grasslands of the world which are found in areas of limited precipitation and cold winters, and which have provided a rich harvest of grain products for many years after their initial ploughing. It is also so in those other agricultural areas where forest was the natural cover, and where it has now been found necessary to alternate the exhaustive periods of crop growing with restorative periods in pastures. [From Introduction]
  • Thumbnail Image
    Item
    Some factors which may influence root formation in conifer cuttings : a thesis presented in partial fulfilment of the requirements for the degree of Master of Horticultural Science at Massey University
    (Massey University, 1981) Basham, Claire Alice
    Seasonal fluctuations in adventitious root formation capacity of cuttings of Juniperus virginiana L. 'Skyrocket' ("easy-to-root") and J. scopulorum Sarg. 'Pathfinder' ("difficult-to-root"), as indicated by three parameters, was determined over a nine month period from late summer (February) until spring (October). Rootability rose from a low or moderate level in late summer to an optimum in mid winter after an intervening period of low potential and diminished again in spring. A less comprehensive study of Cupressus sempervirens L. 'Swane's Golden' ("easy-to-root") revealed that rootability was high in February and June but low in March. The most marked difference in the pattern of seasonal changes between the two juniper cultivars occurred in the percentage of cuttings rooted, which increased dramatically in J. virginiana 'Skyrocket' in April and remained at high levels before declining sharply in October but remained low in cuttings of J. scopulorum 'Pathfinder' until the optimum was attained suddenly in June and diminished thereafter. Generally more gradual changes occurred in the other parameters. Air temperature treatments of the stock plants and cuttings induced significant differences in level of rooting achieved in cuttings taken in mid winter. Material of J. virginiana 'Skyrocket' and J. scopulorum 'Pathfinder' from stock plants which had received normal winter chilling had a greater root regeneration potential than that from plants maintained in a heated glasshouse since autumn. The converse was true for cuttings of J. scopulorum 'Blue Haven' ("very difficult-to-root") and C. sempervirens 'Swane's Golden'. The effect of cutting environment was rather more variable but material which had been exposed to the most favourable parent environment tended to root in greatest numbers in an unheated compared with a heated air environment. Responses of J. scopulorum. 'Pathfinder' and C. sernervirens 'S.vane's Golden' under controlled environment growth cabinet conditions confirmed these results. The attainment of a high rooting percentage in cuttings of J. scopulorum 'Pathfinder' in mid winter appeared to be dependent to a large extent on exposure of the stock plants to low temperatures. Results from the seasonal study generally coincided with the commonly held opinion that phase of growth may be an important determinant of root formation potential in narrow-leaved evergreens. It was suggested that the promotion of rooting in chilled material of J. virginiana 'Skyrocket' and J. scopulorum 'Pathfinder' may have been associated with the stimulation of shoot activity brought about by that treatment but there was no conclusive evidence to support this. Analysis of endogenous growth regulator content was conducted in material from different cultivars, temperature treatments and harvest dates. Level of an IAA-like growth promoter seemed to be the least related to differences in rootability. Estimated ABA and total cytokinin content appeared to be inversely related to rootability in several instances.
  • Thumbnail Image
    Item
    Root disturbance and washing effects on shoot and root growth in four plant species : a thesis presented in partial fulfilment of the requirements for the degree of Master of Applied Science at Massey University
    (Massey University, 1998) Ma, Lina
    Bare-rooting techniques have been widely use in New Zealand nursery production for the preparation of live plants for export to overseas or domestic markets. Bare-root transplants can fail quality requirements due to death or deterioration of regrowth following repotting. The potential for improving bare-root nursery stock quality has prompted study of the morphological effects of removed medium treatment on plant. Two experiments were conducted to explore the effects of physical root disturbance by shaking and washing on the growth and development of camellia (Camellia x saluenensis cv. 'Donation'), pittosporum (Pittosporum tenuifolium cv. 'Kohuhu'), pumpkin (Cucurbita pepo cv. 'Crown Hybrid'), and coleus (Coleus blumei). The shaken plants in both dry and wet conditions suffered a reduction in the growth rate of their leaves compared to the unshaken controls. Root washing influenced the vegetative growth of four species and reproductive growth of pumpkin. The two woody species were more sensitive to treatment stress. Very short time of washing (three seconds) affected camellia bud break and new shoot growth, and inhibit pittosporum root and shoot growth. Similar effects were not sosevered in coleus and pumpkin.
  • Thumbnail Image
    Item
    Factors affecting the soil binding capacity of the root systems of some populus and salix clones : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Botany at Massey University
    (Massey University, 1973) Hathaway, Robert L
    Man-induced changes in the vegetation of New Zealand over the last century have resulted in large areas of actively eroding land, both in the steeplands which still retain a form of forest cover, and in large areas of moderate to steep hill country cleared for pastoral use. By 1941, the seriousness of the problem had been recognised, and Catchment Authorities were constituted, under the auspices of the Soil Conservation and Rivers Control Council, to undertake river and erosion control programs. Many techniques were used in erosion control work, but most emphasis has been placed on the planting of trees, largely Populus and Salix species. The planting of trees has proven to have a beneficial effect on counteracting erosion by slumping and gullying, both in retired areas and in those still grazed. It may be assumed that this effect is due primarily to the reinforcing and binding effect of their root systems. The reduction of soil moisture by evapotranspiration is considered to be of secondary importance, as water loss from these deciduous trees is very low in winter, which is the period of maximum soil moisture content and thus maximum instability. In the past, the selection of poplars and willows for erosion control purposes has been based on the growth and characteristics of the shoot of the tree, while almost nothing was known of the root systems. Variations in morphology and strength of root systems obviously are important factors in the selection of the most suitable species or varieties for soil stabilisation purposes. Objectives of the study The primary objective of the study was to Investigate the morphology, anatomy, and soil binding capacity of the root systems of a representative number of Populus and Salix clones, in order to determine whether any of the clones were likely to be superior for soil stabilisation purposes, and to determine which characteristics of the root systems were most important for this purpose, as a basis for the selection of improved varieties.
  • Thumbnail Image
    Item
    Some endogenous factors affecting root formation on hardwood cuttings of two clones of apple (Malus sylvestris Mill.) rootstocks : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University
    (Massey University, 1976) Tustin, Donald Stuart
    Hardwood cuttings of easy-to-root (MM 106) and difficult-to-root (EM XII) apple (Malus sylvestris M.) rootstocks were sequentially harvested and planted according to the East Malling system, over a period from late autumn (April) until early spring (October). Tissue samples collected on harvest dates and from cuttings undergoing root initiation, were analysed for endogenous, plant growth regulators. Promotion of root formation by a concentrated, quick-dip treatment of Indole-butyric acid (IBA) was only observed in shoots with a high natural ability to initiate roots, when planted as cuttings. Root initiation potential appeared to be directly related to endogenous levels of an indole-acetic acid (IAA)-like growth promoter. No positive correlation between root initiation and bud dormancy, endogenous Abscisic Acid, Cytokinin or Rooting Cofactor levels was established. Reciprocal donor-grafting experiments showed that a root promoting stimulus was graft transferable from MM 106 into EM XII and that a promoter chromatographically similar to IAA accumulated in EM XII stocks grafted with MM 106 scions. No active rooting inhibitors were located from the seasonal or donor-grafted tissue samples. A separation of the modes of action of IAA and IBA in promoting root formation was shown. IAA appeared to be the fundamental physiological promoter of adventitious root formation; the number of roots increasing with an increased concentration of IAA. IBA seemed to have a supporting role in promoting root formation, and could not further promote rooting if applied at increasing concentrations above a threshold level. IBA appeared to be active in the root initiation process by protecting the endogenous IAA levels in the cutting base. Studies of the metabolism of 14C-IAA in the cuttings base indicated that IAA was protected from enzymic degradation and conjugation (both inactivation processes) by the application of IBA prior to planting. IBA was only active in promoting rooting if an optimum level of IAA was present. The results are discussed in terms of the integrated control of root formation on woody shoots and a hypothetical model of the physiological control of root initiation is proposed on the basis of the present work and evidence available in the literature.
  • Thumbnail Image
    Item
    Time course of root initiation and development in perennial ryegrass – a new perspective
    (New Zealand Grassland Association, 2010) Robin, Arif; Matthew, C.; Crush, J. R.
    Perennial ryegrass (Lolium perenne) tillers of cultivar ‘Alto’ were grown in hydroponic culture in winterspring and autumn experiments and roots of known age were individually dissected and a number of properties including dry weight, main axis length and total length were measured to define root developmental status at successive positions or phytomers on the tiller axis. Root initiation occurred about 5 leaf appearance intervals after leaf emergence at the same phytomer and co-located on the tiller axis with leaf senescence. Root development exhibited co-ordination between successive phytomers as previously described for leaf turnover, but with approximately five adjacent roots developing at any one time. There was little or no root main axis elongation later than six leaf appearance intervals from root initiation, though total length of roots continued to increase for a longer period, especially in autumn.